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I don't understand why a flash evaporator would reduce scale build up. Probably because I can't visualize it; do you know of an image or paper I could read to clear up this idea? Thanks for all you contribute, Grady. I love it.
Oh yeah, private water companies have such a fantastic track record. That will definitely save costs in the long run. Yep. Please, do come and visit the UK; boat in our pristine waterways and relax on our totally not sewage covered beaches. All this in return for the £54bn in debt which they have totally assumed responsibility for and definitely won't have to be picked up by the taxpayer. /s
I've drank literally thousands of gallons of desalinated water over 20 years while I was in the US Navy. First ship used 7 stage evaporators and the last two used reverse osmosis. You couldn't tell the difference between them since it was pure water that came out of them and the engineers added minerals back into them to make them drinkable.
@@johnmicheal3547 Its not an engine. Its a desalinization plant. The chemicals are put in the water using a metering device before the water goes into the storage tank on the ship. We only had bromine injection on our ship. Bromine is used to kill any bacteria in the water.
Same here. The water got interesting on one of the big decks I was deployed on when it tried to distill saltwater fouled by fuel dumped by a Harrier. The "drinking" water tasted and stank of JP5 for weeks.
On our ship(USS Camden) we were fine with just a 5 stage evap. One was in the forward MMR and one back aft. The one back aft always made more water as my evap had a vacumn leak somewhere in the aux exhaust preheater that I could never find(but made a great shower during shutdown when the vacuum was broken lol) Sounds like you were on a carrier lol.
I'm a Navy veteran and I served on a Nuclear Aircraft Carrier. We had a desalination system built into the Reactor system using the excess heat from the steam powerd turbines. It was actually very efficient.
@adrieltc sadly nuclear doesn't have large profit margins. So big energy used the fear of radiation and meltdowns to justify closing plants... then went back to fossil fuels.
It is SO extremely important how you put things in perspective in these videos. “It took X kilowatt-hours to do this process.” You could end there and compare numbers at the end, but then people wouldn’t understand what that actually means. It’s great.
And then he dissed Nuclear... Which makes his points all moot. If you diss Nuclear, you don't deserve to have electricity in the first place. And that's probably why he lives in the eternally worsening state of California. Which only has 1 Nuclear Power Plant left, and constant power outages because oh look at that, these brainlets think Wind and Solar are good sources of energy... Let me tell you this, You'd require to cover the Entirety of the USA in Solar Panels to cover the global energy usage per day on Earth. You'd only need 2000 Nuclear Power Plants. And when they succeed with Fusion Plants, that number would drop down to 20.
@@Rncko yeah, it's weird that that point was made against evaporators, while the ~$7/mo of industrial membrane plants wasn't expressed. that is only the primary desal step though, but even if we were to posit that all the rest of the costs increase the price by 5-10x (which would be completely ludicrous) it's still just $35-70 per month. not great, but not exactly catastrophic.
I grow salicornia (sea asperagas) at home and it does surprisingly well turning salt water into usable water and a snack thats pretty dang salty and not bad tasting in my opinion. Not sure if its great for every purpose but here in florida it works pretty well.
Here in Uruguay we are facing a drought right now, and the government decided to mix treated salt water in the normal fresh water supply, so now we are getting water on our taps with a salt concentration about 10x of what it used to be. This video turned out to be very well timed for us.
@@alexalekos no, they're literally running out of fresh water so they're using treated salt water to pad out their remaining supply to meet demand until sufficient rainfall. read.
@@alexalekos The water is well treated but they're purposefully blended with high salt water to increase the supply. Bad treatment would mean accidental dumping of salt water, no removal of toxic chemicals or bacteria, etc.
Lived in Saudi Arabia for a while and dad worked at the desalination plant there. Interesting bit was steam generated by the boilers were split into two pressure points. High pressure steam was used to turn the turbines to produce electricity while low pressure steam was used to make fresh water. Interesting when I heard about it the first time.
That’s what I was wondering why should it “cost” energy to generate steam. Isn’t basically all of our energy added to the grid by steam spinning a turbine? Surely theres some way to spin a turbine and then drink that same condensed water vapor right?
@@jakeannett6720 This is a great thought, but sadly there are some big drawbacks. The water used in most power plants is highly purified and the same water is used over and over again (closed loop) Using sea water would lead to more corrosion and mineral buildup in the pipes and mechanisms of the powerplant. It might also wear down the blades of the turbine.
On our 470' research vessel housed 130 people, we had two distillers plus a reverse osmosis. The distillery was pretty brilliant as we pulled a vacuum on the container and we used heat from our diesel electric engines. When the vacuum was applied the water would vaporize at 165°F rather than 212° F pretty clever. The units on our ship produced 1200 gallons per day. Some of that water was additional purified by R.O. So the waste heat from the engines was not an additional cost only the energy used by the pumps was energy negligible.
It was really clever to drop the pressure below atmospheric in the container. Thus reducing the boiling point of the water🤔 did you just use the already existing vacuum to vent the gas out of the container. Or did you have to use a constant vacuum pump for that?
I can only assume pumps would be needed. But if the baseline vacuum pressure; the bulk work is established using venturi pumps/valves, then you can certainly leech that from a multitude of engine and auxillliary systems. Basically anything with a suitable fluid flow range can be exploited using venturi effect to generate vacuum without a notable energy or efficiency loss to those systems - because venturi is sort of a "skin drag" effect; it doesn't require any direct interference with or impedence of the fluid flow itself. You certainly _can_ bottleneck a flow to accellerate it and boost the vacuum pull of the venturi effect, but with large flow systems already in place and available then mass can go a long way in making up for speed. On a ship, engine inlet air, engine exhaust and coolant flows are probably the most interesting ones. Especially exhaust as its alrady waste energy, fairly high flow, and most venturi applications wouldn't really have much impact on the ability to use the same exhaust gases for _thermal_ energy. Then vaccum pumps might only be needed for moderste boosting, or as an inline support system to ensure adequate "vacuum pressure" stability.
@@jippo91I remember working on a similar one at a company I used to work for. It has to be a constant vacuum. The issue is that with the little heat needed (compared to standard boiling point). The water's evaporation aka expansion reduced the vacuum in the chamber. So we had a pump to maintain a constant vacuum. Here's the cool thing. The pump was a mechanical vacuum pump that was also ran by the motors fan belt.
Really great explanations and comparisons. Thank you for taking the effort to set up the bench top examples. I believe that desalination won't come into popular view until it is the only choice left for larger regions of the world outside of the middle east. As mentioned, water is plentiful but the amount of energy it takes to transport it and prepare it is key.
I worked in a power plamt that used a multistage RO to clean up produced water from an oilfield. The oil was separated, and the water was run through softeners, but it was still in the part per thousand range. We ran the RO at 75% permeate and 25% reject in the winter. We had to run it at only 70% permeate in the summer due to the water being much hotter. Input temperature and pressure have a high effect on the process. We got
@@sealpiercing8476 DI water was used for injection into a GE frame 6 gas turbine for NOx control. Some of the RO water was used in the engine inlet evap coolers to increase air density and improve power output (more air, more fuel). One plant that my company operated started with well water. The sequence was sand filter, carbon filter, softener, another carbon filter, RO, deionization. At each stage some of the water got sent to the next stage and some got used in a process such as the majority of the soft water being used as makup water for the boiler. All effluent streams (incuding rainwater) ended up in a flock tank and then a press. No water was allowed to leave the plant except as vapor from the inlet coolers and the cooling tower. Even black water was run through a mini sewage digester plant. The water that came off the press went back into the cooling tower. The solid “cake” that came off the press was chemically and mechanically identical to limestone, but was still classified as hazardous waste and had to be disposed of accordingly. We bagged it, and shipped it to a facility that stored it. The facility was, appropriately enough, an abandoned limestone quarry. That was the only zero discharge plant I have ever seen. Even then, the government wanted to dispute that classification since the bagged limestone left the plant. There was a tax break involved for being a zero discharge demonstration plant. Our lawyers pointed out that under their criteria it was impossible to have a zero discharge plant because some evaporation is required in any power plant. In the end, both sides decided to nullify any contracts and abandon the project. As far as I know, the plant is still rusting away, and nobody is attempting that kind of usage efficiency today because when they look at doing it that plant is held up as an example of a failure, even though it really succeeded. All because a government bureaucrat wanted to avoid giving a tax break.
Here in Tampa they tried to build a RO desal plant near the Apollo Beach Power Plant. The biggest issue was not any of what you outlined here. The problem was zebra mussels. They are a non native invasive species that would collect on the intake pipes for the desal plant and they were spending 100's of thousands of dollars each month just to keep the pipes clean, and that is what killed the project in the long run.
Not sure why one of the wettest states in the US needed a desal plant anyway. There's no way they would make any money when their competitors would just be collecting and treating the readily available freshwater for basically free by comparison.
This is exactly the kind of unforeseen challenges that he was talking about. For new technology you often have no idea what issues might show up along the way.
I live in Malta. Most of our water is desalination water. Pure water without added minerals will eat and absorb almost anything. I worked at well known soft drink bottles and our water filtration room looked like a water fountain. It was made of solid stainless steel. Amazing what water can do .
Desalination plants combined with gen 4 nuclear power plants equals cheap carbon free electricity and as much water as the world needs. Unfortunately governments would rather control us with blackmail and fear.
Yes - deionized water will alter taste in your mouth just by sucking in all the minerals. Naturally there should be a little sodium, calcium, magnesium, chloride, sulfate etc. in the water for it to taste fine.
That's exactly why the pipes in nuclear powerplants have to be high-quality stainless steel. The reactors have to have 100% pure water. Otherwise, you end up with a ludicrous amount of buildup in the cooling pipes, which is.....less than optimal.
Really good explanation of it all! I’m an operator at a large ultrafiltration membrane plant not far from the Carlsbad plant. Membrane technology is definitely our future and we are going to see more sea water RO plants popping up as our population grows in the U.S.
The problem though isn't technical, it's political. Most people who live in cities are working class so capitalists are not going to build a desalination plant. Just like with electricity in the 19th century the government will have to step up and make massive investments in hundreds of giant desalination plants and set up huge agencies to operate them. The problem is that most western governments have become incredibly timid about huge projects like this and just like railways desalination is a very all-or-nothing thing. You have to commit to it or it will be a total failure.
@@MrMarinus18 wat? None of what you posted here makes *any* sense. Most cities literally can't *have* a desalination plant because *they aren't near the ocean*.
@@vyor8837 Nuclear power is one of the most expensive power sources. It would make much more sense to use solar power, especially since drought conditions usually come with a lot of sunshine.
Can I say I find something profound in this channel. There is so much mystery to our day to day but we are too busy to notice. When you read between the lines, this channel not only streamlines education, but also helps us understand why our modern society is built the way it is and makes us analyze and criticize. Keep it up!
Just saw a vid about cheating in research in order to be published. Hmmm ... I tried to find it but can't. Lots of other sources on same thing though. Google: Harvard gina cheat
"too busy to notice". Wow. that is such a sad state of affairs. "Too busy noticing" Would be better, and it IS a choice. ...and hey, you're here! You are noticing.
Brine water is used a lot in Europe for closed vertical ground source heating or heat pumps. Brine water is a useful resource to transport heat energy without the risk of the medium freezing.
That's cool. The game I play a lot call oxygen not included has brine and salt water that is mainly used for coolant because it doesn't freeze. I didn't realize that that's a real thing. Just thought It was game balance.
@@dr.chimpanz.1324 ONI does have a good bit of sci-fantasy elements (the funny reverse entropy device for example), but almost all of the physics in that game are based on reality, if a bit exaggerated and simplified.
I think one reason people may have a hard time wrapping their head around how difficult it is to get the salt out of the water is that they can’t see what it does - it’s not just swirling around in there, it’s dissolved - it’s harder than getting the cream back out of your coffee
@@LiborTinka yes the suns energy runs the planet. we are still highly dependent on fossil fuels - which are depositories of the suns energy from millions of years ago. by the way, the energy to charge batteries comes from fossil fuels so don't drink the Kool-aid
@@WalterOMSD Because it is energy prohibitive... and that is the only actual reason. Most of the "issues" here are because they are trying to make it economically viable not because it is super difficult.
After major draughts around 2007 in South East Queensland a desalination plant was added, but it was only part of the solution. All of the major dams across the region were connected via pipelines to help balance water supplies. Water can be pumped between areas of the region and the desal plant is used only when water is needed and can also be used as a buffer load on the power network too from what I understand
I work in water treatment in my county as an operator. We adopted membrane filters in the mid 2000's and there are very few treatment plants (at least in Canada) with this newer technology. Our membranes are made by PALL. It's such a new technology that the lifespan of the membranes is still unknown (outside of salt water). We have ordered a complete new set of membranes that will be replacing the old ones next year but this is only cautionary and not reactive. Our tmp's (trans membrane pressures) have held up with only minor, routine maintenance. Our effluent remains well within the 0.1 micron spec and our turbidity exceeds our provincial standard by multitudes.
@@seneca983: True but the pump guts are ceramic, stainless steel and silicone rubber so clean salt water should not hurt it. 600 psi is under half it's water blaster pressure so should not be strained either.
@@howardsimpson489 If it's stainless steel it would probably corrode somewhat faster than otherwise. Stainless steel isn't really completely stainless. Though maybe it's not a big issue.
One thing he forgot to mention is that reverse osmos is extremely reliable. Let me explain, I'm from Ukraine, and more than 20 years ago, my father bought a 20 liter per day plant for $100 (from the US by the way). And you know what? We have not changed the osmosis even once in all the time, only every 2-3 years the primary filters. And the quality of the water hasn't changed. It's really amazing technology and now it's also cheap.
Hi, I'm wondering whether u or anyone u know who understands the desalination process would consider it at all possible or practical to share this process with other engineers located in Gaza. It's a big stretch but surely there would b people there who could benefit and use that knowledge in some way as drinking water is so scarce. Or even turning fetid water 💧 into drinking water using tablets. Just trying to offer some solution to their current situation which appears dire. And BTW, I pray for ukraine and its liberation from Russia everyday.
The potential for a problem with outsourcing to the private sector, is one that seems to be happening right now in the power sector in my part of Australia. Our energy sector was privatized in the 90's, and since then, the problems with the plants have increased over time, plant maintenance, and regulatory requirements often getting overlooked in favor of maximizing profit margins. Now, the plant owner, after years of neglecting the equipment, when faced with a generator that needed replacing, instead decided to shut down the power station, and simply walk away, now, the remaining 2 stations that service the majority of the state, also have closure dates before the end of the decade, with no talk of replacements other then unreliable renewable's such as wind and solar, which currently make up 21% of the market (except during the summer months when diesel generators are used to offset the demand) These are some of the reasons that for anything utility related, I personally support state or city owned assets, especially for power, water, and communications.
Same ol' story. The "unnecessary" costs that get cut by the private sector are long-term vision (designing for the future; maintaining existing equipment so it lasts beyond short-term profit windows; etc), safety, and living wages. Basically the kinds of things you want for your children and your children's children if you're a decent human.
This is exactly what I thought would happen, and it is why I was kinda shocked when the video said that it was a good idea to let the private sector take the risk. We are talking about a resource essential for life, the risk will eventually and ultimately reach the population.
@@annamyob The other flow on effect since the sector was privatised, and I can only go by talking to people taht have been in this region lot longer than I have, but they say that we've lost SO much in terms of skilled workers and knowledge. Some of the equipment was essentially scrapped, because there was no one left that knew how it worked, or how to repair it. You hear the same storys all over the globe when this kind of thing happens, and profit becomes more impportant than the service it provides.
This is my favorite form of P.E. video; a lecture with a real-world demonstration. Grady, please have a meet and greet in S.A. I live in Austin but have been watching since the beginning. I recently was accepted to UT Austin for physics (a returning 30-year-old with a GED.) Your channel has kept me engaged in engineering and has helped me move towards the goals I currently have set. I would love to shake your hand, or elbow bump, and/or even just buy you a beer and pick your brain for a moment. Thank you for all that you do, Sam P.S. I bought your book but missed out on the signed copies. I would be more than willing to donate to a charity of choice for the opportunity to get a signature should I ever get the chance to meet you.
I live on a sailboat and am in the process of building a water maker system that processes saltwater and filters it to fill the drinking water tanks in my boat. This is very useful information.
Salt flats were once massive brine pools. RO and pumping the brine onto large desert lake beds adds to the evap cycle. Salt deposits can be broken up and stored away. Also thinking about MITs recent answer to desalination which uses ion concentration polarization omitting the need for pumps or filters and can run off a $50 solar panel, it's less than 22 lbs, simple to operate and about the size of a small suitcase.
An idea I've long wondered about in areas where seaside land is fairly cheap, such as the Middle East: seawater canals with an arched greenhouse over the top with collection gutters on the sides. Water from the canal evaporates, condenses on the greenhouse, and runs into the collection troughs. I'm sure this would be more complicated in practice, but it seems like a good way to use solar energy in a passive manner.
Armchair science time. This could run into issues with creating flow. There are no rivers flowing through Dubai (other than a creek with the sea on both ends), according to a cursory check of Google Maps. So you’d need to induce flow to prevent salt and organism buildup. Flow could also reduce the efficiency because the new water would need to heat up. Also, the space vs. output might be an issue for certain areas, although if you live in a desert there’s probably a lot of available space. I’d bet you could get more out of a solution like this with a bunch of (pretty cheap) mirrors too. Cool idea
I'm currently drafting for a big waste water treatment plant in Texas and there is so much more to these facilities than I would have ever thought. I really appreciate that cities invest into these types of things.
The real world is so complex.... I'm in programming and the software code I saw in my first job was way more complex than anything I've seen in school.
I live on a small island of 22km², desalination is the only way to get city water. Although the vast majority of homes have cisterns for rainwater recovery, the island has a fairly modern plant equipped with both desalination systems, reverse osmosis and desalination by vacuum/low pressure evaporation, for the latter the heat used is that of the waste incineration plant. But personally I rarely use city water as I have two cisterns under my house for a total of about 70m³ with charcoal-UVC filtration system. But it’s always good to have this backup.
Nuclear powerplants are basically just "big waterboilers." Many of them are of obvious reasons situated near oceans. In them you get a lot of desalinated water steam in them, which easily can be collected and used as drinking water, and many nuclear power plants has that dual function: generate electricity and desalinate water. THIS is the easiest and cheapest way.
On the one hand, this is a really cool idea, but on the other running salt water through a nuclear reactor seems like a really bad idea. Besides the increased risk of the cooling lines becoming gunked up and breaking, it seems like it would introduce a lot of extra maintenance load for the nuclear plant.
@@oscarsmith3942 I have no idea how they do it but couldnt they just use salt-free water to cool the reactor? then use the heat to desalinate a separate tank of salt water
@@Zaque-TV As a kid, I used to bathe in the ocean near the Swedish nuclear power plant in Barsebäck. Because of the cooling water from the reactors, the water was always quite warmer there than in other parts of the beach. That beach was (and is!) very popular, and the water is, of course, not radioactive whatsoever.
I was just wondering about desalination yesterday! It’s super cool to learn about the engineered world even if this isn’t something I’m studying. Thanks for informing the masses Grady!
Today, global sailors (boats of 30 to 60 ft or so) mostly have a desalinater on them. These sailboats have good solar power and storage on board so they can power the desalinator. The sailors also learn to conserve both electric power and water. Find numerous YT vids about installing and using such systems.
@@kmanccrseagulls can drink salt water cuz they have these salt glands that lets them cry out excess salt. I personally think that’s freaking dope. If we had that we wouldn’t have a water crisis
@@codycast No but the salt isnt removed from the ocean... ie they aren't desalinating the ocean are they? they put the salt back into the water. I guess what op is getting at is how their kidneys regulate salt and remove it from their blood and to replicate that process at scale.
@@codycastDo fish drink at all? Can it be called drinking when your entire life takes place fully submerged? Edit: looked it up and answered my own question. Saltwater fish do drink because the salty water draws water from their less salty bodies. Freshwater fish do not drink however, their bodies are saltier than the surrounding water so they hydrate by osmosis.
I don't know if I agree with that last bit at the end about having the private sector do it. Private sector is out for profit, and do we really want profit driven companies to control the basic necessity of fresh water?
One of the most interesting things you can see is where a fresh water river flows into the sea. From overhead, you can literally see the boundary between these two different sources of water as they mix. It is worth noting that the conditions in sea water intake vary day by day and even during the day. So conditions in a desalination plant have to be monitored closely in order to ensure efficient operation and a good product at the outlet.
In some places, they have plants that win energy from this mixing, sometimes called "blue energy". This clearly shows it takes energy to get the salt out.
I really love the information you put out here. The only point I disagree is the privatisation of water treatment. Companys and investors deciding prices for drinking water after contracts have run out. There have to be other ways for water desalination or use of water rights.
Exactly. Privately-owned public utilities is a much greater evil that he realizes. But he is extremely didactic when it comes to explaining engineering & chemical situations so I shall continue to subscribe. And that (misguided) statement was a very small part of an otherwise tremendous video.
It's pretty frustrating. How does the private company compensate for the risk? Why, by charging more than it would ever cost! Governments are big enough to compensate for that themselves, *without* also needing to compensate boards and shareholders.
@@hairymcnipples the problem isn't risk but lack of competition. It's usually hard to have multiple infrastructure providers in a location in a reasonable way
The contract could be for a certain percent above cost for the lifetime of the plant. The contract just needs to be written well. There may be cases where a local government simply can't afford it, or it doesn't make sense for one reason or another. I agree that allowing private companies to control it is an issue, but if well controlled by the contract it shouldn't be a problem.
I lived in a small Florida gulf coast city for years and this is how they got their water. It was very good. The only time I noticed a difference is if we filled the bath tub - the water had a greener appearance than what I was used to seeing in other cities. But again there were no taste or other useage issues for us.
@@ohio_dino Simple, it's cheaper than bottled water and isn't unsafe to drink. And in the past, it was the only game in town, as commercial bottled water on a wide scale is actually fairly recent. As in, I remember when bottled water was becoming common, and I am not old. More often, you would have water distribution stations where you put in say a quarter for a gallon of actually fresh water, which would be poured into the jug/bottle you brought with you, of paid extra for one to be provided for you to be reused. This was, and still is, common in places in the US where the tap water is of dubious quality and safety for consumption despite purification work. There are regions in this country where I will not drink tap water because of that. Most are in the Midwest, where local corruption actually made the water dubious to drink at the best of times, courting poisoning from industrial runoff or typhoid at the worst due to the ones supplying the water not investing properly in water purification, or keeping the systems well maintained due to taking the cheap route and pocketing the difference when they aren't outright embezzling the funds. A good bit of advice is to ask the locals if they drink the local water, and to generally not do so outside of major metropolitan areas anyway. What's good for general use like washing, bathing or showering, is not necessarily something you may want to drink. And yes, I am talking from experience here. Far less of a problem today, but it's still there. All it took was getting typhoid once to learn that lesson.
Desalinated water, depending on the desalination method and the plant, can have a vastly different flavor profile, when it actually has one, than what most of us are used to, though. And the slight green coloring may have been a dye so you would know the water was safe to drink.
@@jgkitarelman… it’s insane that a highly developed country such as the US still hasn’t got some sort of national initiative in place to provide equitable access to drinking water.
I ran evaporators in the Navy and drank the water for many years, it was pure enough to run through the boilers without building up excess scale as well. Tasted great, and made a mean cup of coffee.
I was in the Royal Navy as an engineer and worked extensively on desalination and distillation equipment. After leaving I travelled as a civilian desalination engineer....brings back memories..
On looking back on this video today, what it highlights to me is that we need to seriously need to care for our present Reserves of water, surface water to ground waters, don't have fracking anywhere near these water reserves.... Thom in Scotland.
@@Marcus-p5i5s Desalination has been around and know of for some thousands of years, easy might be your take on it,. Expensive would be my take on desalination......And .... Fracking pollutes surrounding waters, and ground above and below surface.... To be avoided. Thom in Scotland.
If you found out how the private company pay fines for dumping chemicals and paying off employees you wouldn't be as proud. Its a real dirty job and cutting corners in a hands on job like this puts people in danger who work there. Great source of water though...
@@youtubezombiesNono, you've got it wrong. It's possessive, they just removed the apostrophe for logistical reasons. It's actually Carl's bad desalination plant.
Interesting video, I did some work (electrical distribution/transmission) related to the USBR’s Yuma Desalination plant. It’s purpose was to reduce the salinity of agricultural drainage water before it was put into the Colorado river to aid in meeting the requirements of the Colorado River Compact treaty obligations with Mexico.
In addition to the thousands of of plants on land around the world, there are thousands more because almost every naval ship and probably most commercial ships also use desalination to provide most of their water needs. The 30 year old ships that I served on had some nasty water, but it was drinkable (barely so) and the salt levels were low enough not to mess up your bodies balance. That was in the 90s. We also got tons of bottle water training in the middle east which was all desalinated. Those plants actually made water you could stand to drink. P.S. I love the eyeballs on the reverse osmosis machine. :)
I was on the Enterprise, which at the time I was onboard was over 30 years old. But our water was better than the tap water here in Las Vegas. Hard water is the worst. Of course I drank a lot of soda in those years which helps with the taste, but I drank tons of water from the drinking fountains because you have to working in the engineering plants, I don't remember it tasting bad. And of course the soda we got in the middle east was also desal. water.
@jimmym3352 I generally don't do tapwater unless it's fileted anymore. Even in small town USA you never know what's in the water until after its to late. Just like Camp Lejeune and Flint MI. A small town near me had some carcinogens above acceptable levels for over a year. No one knew until the water department sent out a letter saying it had been cleaned up. I assume you are a sailor. Semper Fi brother.
@@curtisroberts9137 water quality where I live in Australia is sometimes rough as well, I was supplying rain water to a couple of friends' families in the late 90s and early aughts because they were constantly getting sick otherwise, it's gotten better but still had times when a whiff of the water has been "I'm just not going to shower for a few days"...
@@cericat I had an aunt that lived in the mountains of Colorado. Their well was all mineral water. Smelled of sulfur most days. Lots of 5 gallon jugs of drinking water delivered there.
I lived in the desert for 25 years. In that period I build very simple solar distillers that delivered less than 1 mg/l total dissolved solids. The feed for my stills were about 2500 TDS. All the water I drank at my home (that really is almost all) came from these stills. There were a few technical improvements in building them but it is possible to produce drinking water (and even water for laboratory use). The problem is that people need to use saline water for a number of purposes rather than purified water because solar distillation gives really pure water but great enough in quantity not in fire fighting or irrigation. When I see this, I realize how primitive our society's understanding of water chemistry is.
During the "Millenium Drought" in Australia the NSW government funded an RO desalination plant to supply 15% of Sydney's drinking water with provisions built so it can be easily scaled to supply up to 30%. It's energy needs were offset with a massive new windfarm just out of Canberra. The plant was finished in 2010 right as the drought broke, so it was mothballed and wasn't used until the 2019 drought
There's a heap running in the other states except for Tas. And of course Toukley planned but deferred back in 2007 in our case. We really do need to reconsider them in NSW since Sydney's water demands can cause difficulties for other catchments, and also to support some of our ag needs rather than impact the regional water supplies.
This channel is one of the most exact, simple; direct, and factual out there for understanding technical topics. Brady covers everything from catastrophes to fundamental physics, in a most eloquent and _practical_ package. Without any pretense to be the most 'scientific' of its kind - yet it manages being most accurate, with hardly any errors or discrepancies on its formal concepts. Something that very few channels and media can claim to nowadays unfortunately. There is so much to be learned from this content... and the exactitude of concepts with simple and clever demos; is just admirable. There is so much engineering and physics content out there, but few are this earnest; and simply true. Fantastic stuff.
Distillation can be a lot cheaper, especially considering it doesn't need to worry about all the other purification and waste disposal steps, once you remember that you don't even need to boil water. It only needs to evaporate. Small quantities of water in a thin film on a warm surface evaporate easily. It's actually super simple for individuals to distill and condense drinking water. It's only difficult at scale.
A big chunk of the energy costs are from chemistry/physics constants like the heat of vaporization of water. If you want water to change from a liquid to a gas that will be 2.2kJ per gram. This is part of why reverse osmosis is more efficient, it doesn't involve boiling the water but will instead have other costs. (Like the energy input to pressurize the water, pressure can be considered a form of potential energy.)
What's interesting is this is the exact opposite of making maple syrup. Both distillation and reverse osmosis are options available to producers. But, in the distillation process, they keep what's leftover in the pan after most of the water has boiled off. And in reverse osmosis, they keep the discharge and reject the fresh water.
@@world_still_spins You can sell the unboiled sap for more. It's eminently drinkable right out of the tree, and the trace minerals are believed to have health benefits. Also, if it's still sweet after RO then you're doing it wrong.
@@oceanceaser44 May not be impossible. There's new tech now that coppices maples, then applies a vacuum pump to the saplings/shoots to extract the sap. Still very new, but apparently very efficient for sap production. If you can get the tree to grow, then it can produce a lot of sap from sub-optimal water sources. The caveat is that it's only in certain climates, and only in the spring.
@@bobcostas9716 yeah, but this syrup is imported wildly to Europe and it is disgusting, very poor quality compared to 'classic' syrups. I am not sure if this is caused by the tech or that they just settle on lower grade syrup.
I have a small wall mounted ultra pure water distiller that uses a flash evaporator in the sense it throws spirts of water on a hot plate. It makes 5 gallons per day and draws less than 10 amps 120v. Pretty neat but super expensive.
One issue with privatizing the production of drinkable water is that it gives private companies a lot power over what's essential to live. They could, on a whim, raise their prices and the state (ultimately, the people) would have no choice but to pay. And there wouldn't be much we could do about it. Private companies have profit in mind instead of public service. Which should be the core goal of utilities.
@@rosskwolfe The question should rather be: how is that in any way similar to the government being completely in control? A State is not a company, and should at no point be run like one. (Looking at you Macron.) Basically, a State making money is failing at being a State. Whatever money it makes could (and should) be reinvested into public services. But even worse than that, a State making money actually fail at enabling the creation and sustainment of companies. The whole point of a State is to enable fairness on many topics. To provide for the unlucky few by taking from everyone. To prevent a lucky minority to gain too much power and control. At no point in time is profitability even a question. So yeah, I'm asking again: what would be similar?
@@rosskwolfe Because it's a captive market which is prone to abuse, the market corrections are not available but with government run the corrective mechanisms are still present. It cuts out a layer of profit making operating costs lower. The government generally has to pick up the bill if it fails anyway whereas shareholders are never held to account for running the company into the ground and skimping on maintenance while walking off with the dividends (looking at you UK privatised water companies).
True but if the problem is huge enough, government could essentially regulate it and the company have no choice but to comply. They of course go out of business if the regulations made it unprofitable. In the end the technology will be developed as long as there are incentives, whether it's profit or public needs.
This is a video I didn't expect, I had to instantly watch it. I've been working with membrane desalination for a while and it looks super simple but under the hood, reverse osmosis still looks like alchemy. Thanks for the video!
18:43 That was one Very Slick Commercial...lol. You should go into Television because I never even felt the "Prick" until it was over :D Great Video though. I learned A LOT, Thank you
Thank you, the camera shots, narration and editing are perfection. The small scale examples you built are a fun little break from other channels summed up wiki info dumps 👌✨
Worked in the water treatment - specifically deionized water - industry for 20y. Ive always thought this technology was just on the edge of becoming a significant supplier of potable water for the world. Thank you explaining why we are still strughling to get there. One thoight ive had is a desal/power plant combo - use concentrated solar energy supplimented by a modular nuclear power plant (boiler water only of course) to convert salt water to steam to power turbines producing energy and the resulting water then is further processed to potable. Removing the salt deposits would need to be mechanical and designed into the boilers to be efficient i would think. Very interesting and pertinent topic for the world
Steam turbines run on superheated steam 500+C You probably don't want to heat your potable water to that temp for efficiency. Just run the solar concentrators it'd be cheaper to just build more of them and run when the suns out than it would be to build a nuclear plant and a conventional RO for backstop. The nice thing about water is it's relatively easy to store for long periods even over months or years. Not hating on nukes but you might as well take the energy from the sun when you can store your output easily.
Add to this the potential use of the by-product. Just keep increasing the salt-to-water ratio and you could potentially have an alternative to the salt mines
It surprises me we can't do anything with the waste brine. It feels like it should be usable in salt harvesting fields or for other uses of sea water. I'm sure there's good technical reasons. Just hope we can overcome those technical issues and use that concentrated brine.
That much brine would be pure poison anywhere but the ocean. Not sure where the Middle East desal plants expels it but I'd guess it's far from the intake pipes.
A really interesting video showing how complex the workings of desalination plants are,I learned a lot about how little I know about this process,but great to watch and come away with a bit more knowledge.
This is really high quality, highly informative and professionally narrated content. Hats off to you kind sir, for summarization such a complex subject while still keeping an objective stance on the matter. Really, really well done.
Thanks for the great video! I learned a lot about the challenges of desalination, but I dont agree on your take on private-public-partnerships. A private company would not agree in a contract if they wouldnt make profit out of it, so in the and such an agreement is more expensive either for the government or the consumer. Also the point of not having to take the financial risk isnt true in reality, because in the case that there is no other way of getting drinkable water (which if I understood correctly is the only reason why you would use desalinated water anyway) the government would have to save the Company financially to keep them operating, because it is no option just to not produce drinking water.
Search for: spacex cost vs nasa "A private company would not agree in a contract if they wouldnt make profit out of it, so in the and such an agreement is more expensive either for the government or the consumer."
desalination is also done with another phase change: freezing. the most common is the 40 stage flash desalination, where the evaporation enthalpie is reused 40 times. besides reverse osmosis, there are others. You neglect that the reduction of alkalinity in the seawater from PH 11 to 8 is the dissolved CO2 in seawater. Important because this gas must be removed to have acceptable heat transfer in the heat recovery condensation surfaces. Your oversimplification has consequences .
Thanks for the informative video. I have worked offshore for years and we always use vacuum distillation or RO to produce water for the living quarters. It's funny when you tell new people that the delicious soft drinks from the soda fountain started as seawater from the Gulf of Mexico that morning.
Great video, but I dissagree on the topic of running the desal plants by private companies instead of governement run. It is usually much more expensive because the private companies try to maximise their profits. Has been a problem with several of the formerly state owned infrastructure here in Germany, e.g. water system in Berlin: it had gotten much more expensive since the government sold it (in 1999, 49.9% of it) to make a shortwhile income. Since the buyback (2013) of the water infrastructure, the prices went down again.
While I agree that utilities run by private entities can be more expensive since my town's electric division has significantly lower rates than the surrounding towns and cities here in the states. I think the point was that smaller towns/cities (large enough though that can still afford desal plants ofc) might not have the money/time/personnel to manage the utilities which may cause it to actually be more expensive. Also, privately run utilities can allow for more innovation; Possibly driving prices down through better efficiency.
@@xing3240 It doesn't make any sense. The costs of running it are what they are. Either you just pay that cost or you pay that cost PLUS the cost of whatever profits the private entity is seeking. The math is simple. Also there is tons of data showing how profit seeking get's in the way of innovation. Innovation has happened despite profit-seeking not because of it.
Lived on the island of Aruba for 11 years off and on. Their water came from the Balashi Desalination Plant that was powered by the Lago Oil Refinery nearby. The water was filtered through large pieces of coral to give it minerals. A Balashi Cocktail was a glass of water. Balashi Brewery is a local beer brewed with the water.
@17:38 the problem with that is: How many corners are the private companies going to cut, w.r.t the environment and how much oversight and inspection is needed?
@@nahometesfay1112 why didn't you give a time stamp? where was the discussion on how to implement it, on how it works, etc.? At 14:30 he INDIRECTLY mentions rainwater, but not rainwater collection. He's referencing ground water, lakes, and rivers. "if mother nature isn't dropping enough water for your particular area" this is wrong, and demonstrates his lack of understanding of rainwater collection and how it's done in such an environment.
You had me until the last bit about private infrastructure. It can work, but not without heavy regulation and oversight - which something that is always argued against when things are privatized.
Dwr Cymru / Welsh water are doing fine as they are a not for profit company. I know Thames Water supply a lot more people but it is in a very concentrated area. Lack of investment and upkeep seem to be the major issue and the fact that they have to pay shareholders just means they have not invested enough to keep the system working. So the choice seems to be....gov buying them out with tax payers money that will go straight to the shareholders while the rest of us are paying higher taxes to pay for the lack of upkeep :/
Also there is the issue of biofouling where bacteria grow on the membranes and clog them after a while. It turns out to be very difficult problem to fully address.
I'd like to know why the "Ocean Vapor Towers" approach doesnt make more sense than these methods, it seems a logical way to get fresh-water from salt-water and it leverages cycles so nature is doing a significant chunk of the work
At that point you're basically engaged in a small geoengineering project since you're trying to change the local climate and that is basically impossible to predict because you have to factor in the entire global climate to figure out what will happen. No one in their right mind would sign off on spending millions on a project that you can't even guarantee the outcome of. If a region doesn't get a lot of rainfall then there's some pretty powerful natural forces behind it and it's fairly easy to conclude that humans can't easily influence that. Like climate change is only happening because our entire global civilization is engaged in the same activity and has been doing so for about two centuries so it really isn't easy to influence the climate of our planet. Also there's the fact that you can't necessarily directly use rainwater, we usually use groundwater which has spent thousands of years filtering through the ground to make it clean. Plants that draw directly from sources such as lakes and rivers still do need some amount of cleaning before it becomes safe to drink and it's susceptible to ground pollution, which an area that experiences little rainfall that would normally wash it out probably has a lot of.
Based on this video it seems that reverse osmosis is a *lot* more energy efficient than distillation. It may seem attractive to use sunlight directly for evaporation instead of electricity. However, if sunlight is plentiful it might still be more efficient to convert that into electricity and use it to run reverse osmosis.
Grady, it might be interesting to do a video on how drinkwater is made in the west coast of the Netherlands. Here the regular groundwater is too brackish, so we combine rainwater with river water by pumping it into our sand dunes, where the sand naturally filters it before we pump it out of the reservoir underneath the dunes.
Here in Israel we have gone from constantly worrying about getting enough winter rainfall to fill the Sea of Galilee (misnomer, it a freshwater lake and serves as the country's water reservoir). Now with several RO plants built, we have enough water for domestic usage plus use the desalinated water to refill the Sea of Galilee if it gets too low as well as transfer water to Jordan.
It would be cool if you went into more detail on the energy recovery systems in RO. Rotary pressure exchangers (one moving part!) are remarkable devices -- and they were invented surprisingly recently. Also, for distillation, I think you're showing a humidification/dehumidification system there. The water vapor is mixed with air. With these, there's a problem with mass transfer at the condenser: the air near the condenser surface becomes dry, and water from the rest has to be transported through this boundary layer (this is not a problem in a vacuum system where only water vapor is present). There was a spinoff from MIT a few years ago that had a new condenser that gets around this problem (bubbling air through trays of water; the bubbles are tiny with large surface area.) I've thought this bubble tray system was quite clever. These were using it to desalinate produced water from fracked wells, reusing the water for more fracking.
Another potentially interesting concept: if you keep increasing the salt-to-water ratio in the bi-product, you could potentially end up with an alternative to salt mines.
@@TheExileFox I think salt isn't worth that much. 1 ton costs arround 300$ It is also not that much. He said sea salt is about 35g per litre , if I rememeber correctly. Can imagine that "harvesting" and selling this salt is more expensive than just pushing it out into the sea before it solidifies.
This was interesting. As a dialysis patients I actually have a water system that starts with two carbon pre tanks and an RO that is about the size of a large computer tower in my home to make medical grade water. Running it about 100 hours a month doubles the household water use but is not that hard on power. The equipment does need to be replaced/refit once a year but the healthcare system pays for that so I have no idea the cost. The tech seems to be there when you need it to live. I think we just won't improve it until there is more money to be made.
Environmental engineer here. It really is not that hard. It's just that it requires a lot of energy. High pressure pumps need a lot of power to reach necessery pressure level 100+ bars, so that desalination (reverse osmosis) membranes let H2O molecules and nothingelse through.
There are quite a few desalination plants in the Cyclades in Greece. For example, the little fresh water that the island of Syros (about 20000 people I think) goes towards things like the hospital or the production of a local traditional product that needs good water. The desalinated water isn't usually drunk though.
Great video. We can look at it the other way too. How do we use less water. This just goes to show how much effort goes into creating something a lot of us take for granted.
Watched this yesterday on Nebula -- I always knew in theory how reverse osmosis worked, but I'd never actually seen one of the membrane tubes. Very cool!
Water conservation methods are often more cost effective than desalinization as well. A municipality can spend a lot of money fixing leaks and implementing water saving policies before you get to the point of using desalinization.
You can also implement grey water systems to help save the actually important water. We use water on a lot of things that don't actually need to be of human drinkable quality such as toilets and watering plants, there's no point in these systems using the expensive and rare freshwater and instead they might as well use waste water from other processes or water from less clean sources. You can implement this both on a municipal level and a private level, ie. in your own house you can have your toilets reuse water from the shower or washing machine while on a municipal level grey water can be reused in industry.
I recall reading about a mechanical technique for desalination a while back. (I think it was an israeli paper?) The idea was to lift a column of water in a sealed tube as high as possible until the weight of the column overcomes the air pressure and the water stops rising, forming a vacuum on top. the vacuum fills with vapor which is then forced out through a one way valve as the column compresses and the falling column which is still mostly liquid water can be used as a counterweight to raise another column. With multiple columns you can create a desalination engine. I'm not sure how this method compare to the membrane approach, but it would be interesting to see.
17:43 Lost me ad clearly advocating to privatization which results in deregulation as the private entity captures more and more of the revenue that would be going into public infrastructure and finds that the cost of lobbying is lower than the cost of compliance. Mmm. PFOAs and agriculture runoff at consistently higher amounts than allowed with no meaningful consequence… yum.
This is fascinating lol. Have seen enough dialysis processes but never thought about using the same filter to desalinate water. also the insane amount of engineering behind an everyday essential ☠️
You didn't even count the energy cost to make that ice tub :). Thank you again for making these incredible videos. Learned so much from your channel. Have a nice day!
One advantage of desalination is that it can be coupled with solar energy production, when there's a lot of solar energy, the plant can ramp up and produce a lot of desalinated water for later use with the cheap solar energy and at night it can be shut down and reduce the energy consumption when there is less power available. There is also a long term correlation, during the summer when water consumption is higher also there is usually more solar energy available.
There's also concentrated solar plants, which use steam turbines to generate their power. You could create a combined distilation desalination-CSP plant and generate power and drinking water at the same time. (I'm surprised this isn't already a thing)
I’m an engineer on an oil tanker, we have an evaporator. We use heat from our main engines cooling water. And an ejector pump to create a vacuum, fun fact. Water boils at a lower temp while under vacuum. Our water is usually 1ppm salinity.
Amazing technical and practical analysis of desalination! I live in Arizona. We have abundant energy in the form of sunshine and wind, lots of open space, fertile ground for growing crops, but we lack sufficient water to continue growing more food and our population. Your timing on this video is amazing because I was just sitting down to research this topic myself so I could do some writing on the economics of desalination for our state using water from the Sea of Cortez. Your video is a great place to start and really whet my appetite to dive into total energy cost per volume of water generated, including pre-treatment, desalination, consumables, pumping and any post-treatment that would need to be done if the water was used for drinking. The interesting thing about our situation here is that we could easily provide drinking water to many more people in this state if we used all of our reservoirs for drinking water. Where we run into problems is with water used for industry and agriculture. I think that it's inevitable that we'll ultimately use desalinated water for industry as the benefits of agriculture and manufacturing here in the state are greater than the drawbacks, such as the need to use processed water. But that case remains to be laid out clearly....
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bruh literally never quote the WHO or WEF ever again.
I don't understand why a flash evaporator would reduce scale build up. Probably because I can't visualize it; do you know of an image or paper I could read to clear up this idea? Thanks for all you contribute, Grady. I love it.
The brine is also a potential source for rare minerals, etc.
why can't the desalination plants harvest the waste brine for salt? selling real sea salt would be a good way to make up some of the cost.
Oh yeah, private water companies have such a fantastic track record. That will definitely save costs in the long run. Yep. Please, do come and visit the UK; boat in our pristine waterways and relax on our totally not sewage covered beaches. All this in return for the £54bn in debt which they have totally assumed responsibility for and definitely won't have to be picked up by the taxpayer. /s
I've drank literally thousands of gallons of desalinated water over 20 years while I was in the US Navy. First ship used 7 stage evaporators and the last two used reverse osmosis. You couldn't tell the difference between them since it was pure water that came out of them and the engineers added minerals back into them to make them drinkable.
How does the engine add the minerals back?
Ship scale is a lot easier than city scale, glad it works
@@johnmicheal3547 Its not an engine. Its a desalinization plant. The chemicals are put in the water using a metering device before the water goes into the storage tank on the ship. We only had bromine injection on our ship. Bromine is used to kill any bacteria in the water.
Same here. The water got interesting on one of the big decks I was deployed on when it tried to distill saltwater fouled by fuel dumped by a Harrier. The "drinking" water tasted and stank of JP5 for weeks.
On our ship(USS Camden) we were fine with just a 5 stage evap. One was in the forward MMR and one back aft. The one back aft always made more water as my evap had a vacumn leak somewhere in the aux exhaust preheater that I could never find(but made a great shower during shutdown when the vacuum was broken lol) Sounds like you were on a carrier lol.
I'm a Navy veteran and I served on a Nuclear Aircraft Carrier. We had a desalination system built into the Reactor system using the excess heat from the steam powerd turbines. It was actually very efficient.
Nobody cares, bud.
nice, i was wondering exactly this. as nuclear and other powerplants have to boil water anyways, why aren't those systems combined?!
@adrieltc sadly nuclear doesn't have large profit margins. So big energy used the fear of radiation and meltdowns to justify closing plants... then went back to fossil fuels.
@@andybaldman I care.
@@adrieltc They are combined at times, but the designs have to be tested thoroughly.
It is SO extremely important how you put things in perspective in these videos. “It took X kilowatt-hours to do this process.” You could end there and compare numbers at the end, but then people wouldn’t understand what that actually means. It’s great.
And then it ends on --> 800$ PER DAY electric bill for utmost emotional damage.
@@Rncko
Honestly, it was better than I was expecting... Although _all_ the caviats were (more or less expected) bummers.
And then he dissed Nuclear... Which makes his points all moot. If you diss Nuclear, you don't deserve to have electricity in the first place. And that's probably why he lives in the eternally worsening state of California. Which only has 1 Nuclear Power Plant left, and constant power outages because oh look at that, these brainlets think Wind and Solar are good sources of energy... Let me tell you this, You'd require to cover the Entirety of the USA in Solar Panels to cover the global energy usage per day on Earth. You'd only need 2000 Nuclear Power Plants. And when they succeed with Fusion Plants, that number would drop down to 20.
The sun does this for free by the millions of gallons a day. No “x watts needed”
It’s not the process, it’s the method. The process is natural.
@@Rncko yeah, it's weird that that point was made against evaporators, while the ~$7/mo of industrial membrane plants wasn't expressed. that is only the primary desal step though, but even if we were to posit that all the rest of the costs increase the price by 5-10x (which would be completely ludicrous) it's still just $35-70 per month. not great, but not exactly catastrophic.
I grow salicornia (sea asperagas) at home and it does surprisingly well turning salt water into usable water and a snack thats pretty dang salty and not bad tasting in my opinion. Not sure if its great for every purpose but here in florida it works pretty well.
interesting!!!
Can you use sea water for cooking vegetables?
freezing water as in sea ice will also desalinate the water.
@@kitemanmusic besides the salt there's also pollution, especially if you get it at a beach near a city. And it tends to be too salty for taste
Very interesting, how much do you harvest?
Here in Uruguay we are facing a drought right now, and the government decided to mix treated salt water in the normal fresh water supply, so now we are getting water on our taps with a salt concentration about 10x of what it used to be. This video turned out to be very well timed for us.
so the water wasn't treated that well?
Si pa?
@@alexalekos no, they're literally running out of fresh water so they're using treated salt water to pad out their remaining supply to meet demand until sufficient rainfall. read.
@@s_t_r_a_y_e_d but 10x the concentration is more than the intended for desalinated water
@@alexalekos The water is well treated but they're purposefully blended with high salt water to increase the supply. Bad treatment would mean accidental dumping of salt water, no removal of toxic chemicals or bacteria, etc.
Lived in Saudi Arabia for a while and dad worked at the desalination plant there. Interesting bit was steam generated by the boilers were split into two pressure points. High pressure steam was used to turn the turbines to produce electricity while low pressure steam was used to make fresh water. Interesting when I heard about it the first time.
That’s what I was wondering why should it “cost” energy to generate steam. Isn’t basically all of our energy added to the grid by steam spinning a turbine? Surely theres some way to spin a turbine and then drink that same condensed water vapor right?
And water cost more than their fossil products!
@@jakeannett6720That's distillation, purify the water of germs and removing salt content but it is the costly method of desalination.
I wonder if they ever thought to use this concept but with a nuclear power plant
@@jakeannett6720 This is a great thought, but sadly there are some big drawbacks. The water used in most power plants is highly purified and the same water is used over and over again (closed loop) Using sea water would lead to more corrosion and mineral buildup in the pipes and mechanisms of the powerplant. It might also wear down the blades of the turbine.
On our 470' research vessel housed 130 people, we had two distillers plus a reverse osmosis. The distillery was pretty brilliant as we pulled a vacuum on the container and we used heat from our diesel electric engines. When the vacuum was applied the water would vaporize at 165°F rather than 212° F pretty clever. The units on our ship produced 1200 gallons per day. Some of that water was additional purified by R.O. So the waste heat from the engines was not an additional cost only the energy used by the pumps was energy negligible.
That's super interesting! Do you think the energy required to place the vacuum in the container cost a notable amount of energy or was it negligible?
It was really clever to drop the pressure below atmospheric in the container. Thus reducing the boiling point of the water🤔 did you just use the already existing vacuum to vent the gas out of the container. Or did you have to use a constant vacuum pump for that?
I can only assume pumps would be needed. But if the baseline vacuum pressure; the bulk work is established using venturi pumps/valves, then you can certainly leech that from a multitude of engine and auxillliary systems. Basically anything with a suitable fluid flow range can be exploited using venturi effect to generate vacuum without a notable energy or efficiency loss to those systems - because venturi is sort of a "skin drag" effect; it doesn't require any direct interference with or impedence of the fluid flow itself. You certainly _can_ bottleneck a flow to accellerate it and boost the vacuum pull of the venturi effect, but with large flow systems already in place and available then mass can go a long way in making up for speed.
On a ship, engine inlet air, engine exhaust and coolant flows are probably the most interesting ones. Especially exhaust as its alrady waste energy, fairly high flow, and most venturi applications wouldn't really have much impact on the ability to use the same exhaust gases for _thermal_ energy. Then vaccum pumps might only be needed for moderste boosting, or as an inline support system to ensure adequate "vacuum pressure" stability.
@@jippo91I remember working on a similar one at a company I used to work for. It has to be a constant vacuum. The issue is that with the little heat needed (compared to standard boiling point). The water's evaporation aka expansion reduced the vacuum in the chamber. So we had a pump to maintain a constant vacuum. Here's the cool thing. The pump was a mechanical vacuum pump that was also ran by the motors fan belt.
Really great explanations and comparisons. Thank you for taking the effort to set up the bench top examples. I believe that desalination won't come into popular view until it is the only choice left for larger regions of the world outside of the middle east. As mentioned, water is plentiful but the amount of energy it takes to transport it and prepare it is key.
To quote the Ancient Mariner: 'Water water everywhere, but not a drop to drink.'
Why not use solar and wind power as part of the energy solution?
I worked in a power plamt that used a multistage RO to clean up produced water from an oilfield. The oil was separated, and the water was run through softeners, but it was still in the part per thousand range. We ran the RO at 75% permeate and 25% reject in the winter. We had to run it at only 70% permeate in the summer due to the water being much hotter. Input temperature and pressure have a high effect on the process. We got
What did you use the DI water for?
@@sealpiercing8476 DI water was used for injection into a GE frame 6 gas turbine for NOx control. Some of the RO water was used in the engine inlet evap coolers to increase air density and improve power output (more air, more fuel).
One plant that my company operated started with well water. The sequence was sand filter, carbon filter, softener, another carbon filter, RO, deionization. At each stage some of the water got sent to the next stage and some got used in a process such as the majority of the soft water being used as makup water for the boiler. All effluent streams (incuding rainwater) ended up in a flock tank and then a press. No water was allowed to leave the plant except as vapor from the inlet coolers and the cooling tower. Even black water was run through a mini sewage digester plant. The water that came off the press went back into the cooling tower. The solid “cake” that came off the press was chemically and mechanically identical to limestone, but was still classified as hazardous waste and had to be disposed of accordingly. We bagged it, and shipped it to a facility that stored it. The facility was, appropriately enough, an abandoned limestone quarry. That was the only zero discharge plant I have ever seen. Even then, the government wanted to dispute that classification since the bagged limestone left the plant. There was a tax break involved for being a zero discharge demonstration plant. Our lawyers pointed out that under their criteria it was impossible to have a zero discharge plant because some evaporation is required in any power plant. In the end, both sides decided to nullify any contracts and abandon the project. As far as I know, the plant is still rusting away, and nobody is attempting that kind of usage efficiency today because when they look at doing it that plant is held up as an example of a failure, even though it really succeeded. All because a government bureaucrat wanted to avoid giving a tax break.
@@sealpiercing8476 what do you NOT use DI water for? it causes far less corrosion and leaves next to no scale/fouling
@@Simple_But_Expensivewow, that's a really good story. are you still in the business?
The theoretical limit of water purity is 18.2 Mohm. In the semiconductor industry we meet a water purity requirement of 18 Mohm continually.
Here in Tampa they tried to build a RO desal plant near the Apollo Beach Power Plant. The biggest issue was not any of what you outlined here. The problem was zebra mussels. They are a non native invasive species that would collect on the intake pipes for the desal plant and they were spending 100's of thousands of dollars each month just to keep the pipes clean, and that is what killed the project in the long run.
Imagine living in Florida out of all places
Not sure why one of the wettest states in the US needed a desal plant anyway. There's no way they would make any money when their competitors would just be collecting and treating the readily available freshwater for basically free by comparison.
@@cowabunga2597considering the amount of people who move down here, I don't think your opinion is the popular one
@@thisutuber You could but that doesn't mean you'd have made any money from it, lime isn't exactly in short supply.
This is exactly the kind of unforeseen challenges that he was talking about. For new technology you often have no idea what issues might show up along the way.
I live in Malta. Most of our water is desalination water. Pure water without added minerals will eat and absorb almost anything. I worked at well known soft drink bottles and our water filtration room looked like a water fountain. It was made of solid stainless steel. Amazing what water can do .
Desalination plants combined with gen 4 nuclear power plants equals cheap carbon free electricity and as much water as the world needs. Unfortunately governments would rather control us with blackmail and fear.
Yes - deionized water will alter taste in your mouth just by sucking in all the minerals. Naturally there should be a little sodium, calcium, magnesium, chloride, sulfate etc. in the water for it to taste fine.
Also called Universal Solvent.
Great stuff.
@@20chocsaday Also hydroxic acid.
That's exactly why the pipes in nuclear powerplants have to be high-quality stainless steel. The reactors have to have 100% pure water. Otherwise, you end up with a ludicrous amount of buildup in the cooling pipes, which is.....less than optimal.
Really good explanation of it all! I’m an operator at a large ultrafiltration membrane plant not far from the Carlsbad plant. Membrane technology is definitely our future and we are going to see more sea water RO plants popping up as our population grows in the U.S.
Or we just use nuclear power, completely removing power draw concerns.
The problem though isn't technical, it's political. Most people who live in cities are working class so capitalists are not going to build a desalination plant. Just like with electricity in the 19th century the government will have to step up and make massive investments in hundreds of giant desalination plants and set up huge agencies to operate them.
The problem is that most western governments have become incredibly timid about huge projects like this and just like railways desalination is a very all-or-nothing thing. You have to commit to it or it will be a total failure.
@@MrMarinus18 wat? None of what you posted here makes *any* sense. Most cities literally can't *have* a desalination plant because *they aren't near the ocean*.
@@vyor8837 Nuclear power is one of the most expensive power sources. It would make much more sense to use solar power, especially since drought conditions usually come with a lot of sunshine.
@@SerienchiIIer It's only expensive because of regulations that exist specifically to make it expensive.
Can I say I find something profound in this channel. There is so much mystery to our day to day but we are too busy to notice. When you read between the lines, this channel not only streamlines education, but also helps us understand why our modern society is built the way it is and makes us analyze and criticize. Keep it up!
it ALso MAKES deSALinAtion exCITing...BUT I'm NOT exACTly SURE how he DOES it!...
Just saw a vid about cheating in research in order to be published.
Hmmm ... I tried to find it but can't. Lots of other sources on same thing though.
Google: Harvard gina cheat
"too busy to notice". Wow. that is such a sad state of affairs. "Too busy noticing" Would be better, and it IS a choice. ...and hey, you're here! You are noticing.
Brine water is used a lot in Europe for closed vertical ground source heating or heat pumps. Brine water is a useful resource to transport heat energy without the risk of the medium freezing.
I never knew that could even be done! Thanks for sharing!
Interesting! Makes sense.
That's cool. The game I play a lot call oxygen not included has brine and salt water that is mainly used for coolant because it doesn't freeze. I didn't realize that that's a real thing. Just thought It was game balance.
@@dr.chimpanz.1324 ONI does have a good bit of sci-fantasy elements (the funny reverse entropy device for example), but almost all of the physics in that game are based on reality, if a bit exaggerated and simplified.
@@fauxfirefurLllLlLall(
I think one reason people may have a hard time wrapping their head around how difficult it is to get the salt out of the water is that they can’t see what it does - it’s not just swirling around in there, it’s dissolved - it’s harder than getting the cream back out of your coffee
Next time observing a mountain creek, let's admire the exquisite amounts of energy provided by the Sun to distill all that water.
Now If only Texas would fix their broken infrastructure that is losing billions of gallons.
@@LiborTinka *low entropy energy
@@AlexanderNashYour comment only serves to show off. Shame
@@LiborTinka yes the suns energy runs the planet. we are still highly dependent on fossil fuels - which are depositories of the suns energy from millions of years ago. by the way, the energy to charge batteries comes from fossil fuels so don't drink the Kool-aid
Thanks for covering the renewable energy part, I've been grumbling about using that for years. Now I have a clue of the continuing drawbacks.
As a water treatment specialist it feels good to be seen. The RO segment was dead on. TDS and scaling are constant challenges.
Same here, this is some great stuff, eapecially when family and friends ask me why don't we just constantly clean sea water 😂
@@WalterOMSD Because it is energy prohibitive... and that is the only actual reason. Most of the "issues" here are because they are trying to make it economically viable not because it is super difficult.
Don't worry, we see you. No need to ever get salty ; )
@@thomgizzizexactly…it’s not difficult at all…it’s just not economically viable
Thanks. My country relies on people like you for about 1/4th of is water supply
After major draughts around 2007 in South East Queensland a desalination plant was added, but it was only part of the solution. All of the major dams across the region were connected via pipelines to help balance water supplies. Water can be pumped between areas of the region and the desal plant is used only when water is needed and can also be used as a buffer load on the power network too from what I understand
I've always been interested in learning how desalination works, I'm glad you've finally done a video on it!
I work in water treatment in my county as an operator. We adopted membrane filters in the mid 2000's and there are very few treatment plants (at least in Canada) with this newer technology. Our membranes are made by PALL. It's such a new technology that the lifespan of the membranes is still unknown (outside of salt water). We have ordered a complete new set of membranes that will be replacing the old ones next year but this is only cautionary and not reactive. Our tmp's (trans membrane pressures) have held up with only minor, routine maintenance. Our effluent remains well within the 0.1 micron spec and our turbidity exceeds our provincial standard by multitudes.
Spoken like a true engineer... "The instructions didn't say to not run salt water through the pump"
Yes. This is another engineer's problem. He is actually helping that engineer discover failure conditions to add to the warning labels.
They will do after this video
That's good. If the pump gets broken in the process he can return it since he didn't use in a way it's not supposed to be used.
@@seneca983: True but the pump guts are ceramic, stainless steel and silicone rubber so clean salt water should not hurt it. 600 psi is under half it's water blaster pressure so should not be strained either.
@@howardsimpson489 If it's stainless steel it would probably corrode somewhat faster than otherwise. Stainless steel isn't really completely stainless. Though maybe it's not a big issue.
Grateful for all that you do with this channel. As a non-engineer, this is an incredibly helpful way to grow my knowledge.
yes!
One thing he forgot to mention is that reverse osmos is extremely reliable. Let me explain, I'm from Ukraine, and more than 20 years ago, my father bought a 20 liter per day plant for $100 (from the US by the way). And you know what? We have not changed the osmosis even once in all the time, only every 2-3 years the primary filters. And the quality of the water hasn't changed. It's really amazing technology and now it's also cheap.
Hi, I'm wondering whether u or anyone u know who understands the desalination process would consider it at all possible or practical to share this process with other engineers located in Gaza. It's a big stretch but surely there would b people there who could benefit and use that knowledge in some way as drinking water is so scarce.
Or even turning fetid water 💧 into drinking water using tablets. Just trying to offer some solution to their current situation which appears dire.
And BTW, I pray for ukraine and its liberation from Russia everyday.
love your accuracy and engineering approach of explaining things: make complex things simple!
The potential for a problem with outsourcing to the private sector, is one that seems to be happening right now in the power sector in my part of Australia. Our energy sector was privatized in the 90's, and since then, the problems with the plants have increased over time, plant maintenance, and regulatory requirements often getting overlooked in favor of maximizing profit margins.
Now, the plant owner, after years of neglecting the equipment, when faced with a generator that needed replacing, instead decided to shut down the power station, and simply walk away, now, the remaining 2 stations that service the majority of the state, also have closure dates before the end of the decade, with no talk of replacements other then unreliable renewable's such as wind and solar, which currently make up 21% of the market (except during the summer months when diesel generators are used to offset the demand)
These are some of the reasons that for anything utility related, I personally support state or city owned assets, especially for power, water, and communications.
Same ol' story. The "unnecessary" costs that get cut by the private sector are long-term vision (designing for the future; maintaining existing equipment so it lasts beyond short-term profit windows; etc), safety, and living wages. Basically the kinds of things you want for your children and your children's children if you're a decent human.
This is exactly what I thought would happen, and it is why I was kinda shocked when the video said that it was a good idea to let the private sector take the risk. We are talking about a resource essential for life, the risk will eventually and ultimately reach the population.
@@annamyob The other flow on effect since the sector was privatised, and I can only go by talking to people taht have been in this region lot longer than I have, but they say that we've lost SO much in terms of skilled workers and knowledge. Some of the equipment was essentially scrapped, because there was no one left that knew how it worked, or how to repair it. You hear the same storys all over the globe when this kind of thing happens, and profit becomes more impportant than the service it provides.
Example nr; 124634588862623 of Capitalism being awful
@@kristoffer3000but I MUST CONSUME
This is my favorite form of P.E. video; a lecture with a real-world demonstration. Grady, please have a meet and greet in S.A. I live in Austin but have been watching since the beginning. I recently was accepted to UT Austin for physics (a returning 30-year-old with a GED.) Your channel has kept me engaged in engineering and has helped me move towards the goals I currently have set. I would love to shake your hand, or elbow bump, and/or even just buy you a beer and pick your brain for a moment.
Thank you for all that you do,
Sam
P.S. I bought your book but missed out on the signed copies. I would be more than willing to donate to a charity of choice for the opportunity to get a signature should I ever get the chance to meet you.
I live on a sailboat and am in the process of building a water maker system that processes saltwater and filters it to fill the drinking water tanks in my boat. This is very useful information.
What are you planning on doing with the brine that is produced?
Hopefully store it for inland disposal.
Salt flats were once massive brine pools. RO and pumping the brine onto large desert lake beds adds to the evap cycle. Salt deposits can be broken up and stored away.
Also thinking about MITs recent answer to desalination which uses ion concentration polarization omitting the need for pumps or filters and can run off a $50 solar panel, it's less than 22 lbs, simple to operate and about the size of a small suitcase.
An idea I've long wondered about in areas where seaside land is fairly cheap, such as the Middle East: seawater canals with an arched greenhouse over the top with collection gutters on the sides. Water from the canal evaporates, condenses on the greenhouse, and runs into the collection troughs. I'm sure this would be more complicated in practice, but it seems like a good way to use solar energy in a passive manner.
that's the best idea in the comment section (I'm a scientist in this field)
Dang that's pretty smart and simple
water like that would start growing organisms
@@techheck3358 So? They can be filtered out easily. The hard part is removing the salt, which this does.
Armchair science time. This could run into issues with creating flow. There are no rivers flowing through Dubai (other than a creek with the sea on both ends), according to a cursory check of Google Maps. So you’d need to induce flow to prevent salt and organism buildup. Flow could also reduce the efficiency because the new water would need to heat up.
Also, the space vs. output might be an issue for certain areas, although if you live in a desert there’s probably a lot of available space.
I’d bet you could get more out of a solution like this with a bunch of (pretty cheap) mirrors too. Cool idea
I'm currently drafting for a big waste water treatment plant in Texas and there is so much more to these facilities than I would have ever thought. I really appreciate that cities invest into these types of things.
The real world is so complex.... I'm in programming and the software code I saw in my first job was way more complex than anything I've seen in school.
I live on a small island of 22km², desalination is the only way to get city water. Although the vast majority of homes have cisterns for rainwater recovery, the island has a fairly modern plant equipped with both desalination systems, reverse osmosis and desalination by vacuum/low pressure evaporation, for the latter the heat used is that of the waste incineration plant.
But personally I rarely use city water as I have two cisterns under my house for a total of about 70m³ with charcoal-UVC filtration system. But it’s always good to have this backup.
Which island? That sounds so cool!
@@TucsonDude St Barthélemy, Caribbean 😉👍
Love this channel. As a trained EE I wish my education had this kind of practical experiments and thought-experiments.
looks like bad education or bad learning imo.
Nuclear powerplants are basically just "big waterboilers." Many of them are of obvious reasons situated near oceans. In them you get a lot of desalinated water steam in them, which easily can be collected and used as drinking water, and many nuclear power plants has that dual function: generate electricity and desalinate water. THIS is the easiest and cheapest way.
On the one hand, this is a really cool idea, but on the other running salt water through a nuclear reactor seems like a really bad idea. Besides the increased risk of the cooling lines becoming gunked up and breaking, it seems like it would introduce a lot of extra maintenance load for the nuclear plant.
@@oscarsmith3942 As I said, it is already happening. And nuclear powerplats do really use salt water. Google desalination + nuclear power plants.
@@oscarsmith3942 I have no idea how they do it but couldnt they just use salt-free water to cool the reactor? then use the heat to desalinate a separate tank of salt water
@oscarsmith3942 is not a bad idea at all. It doesn't make radioactive water lol. Tempurature changes is all.
@@Zaque-TV As a kid, I used to bathe in the ocean near the Swedish nuclear power plant in Barsebäck. Because of the cooling water from the reactors, the water was always quite warmer there than in other parts of the beach. That beach was (and is!) very popular, and the water is, of course, not radioactive whatsoever.
I really love how clear and understandable your videos are! Good work
Additional research is needed to conclude this.
I was just wondering about desalination yesterday! It’s super cool to learn about the engineered world even if this isn’t something I’m studying. Thanks for informing the masses Grady!
What is the theoretical minimum amount of energy that forms the lower bound
Today, global sailors (boats of 30 to 60 ft or so) mostly have a desalinater on them. These sailboats have good solar power and storage on board so they can power the desalinator.
The sailors also learn to conserve both electric power and water.
Find numerous YT vids about installing and using such systems.
Would be interesting to cover desalination in nature. For example, plants, animals and fish which can filter out salt from water...
do they? i thought it was primarily rain that provides desalinated water
@@kmanccrseagulls can drink salt water cuz they have these salt glands that lets them cry out excess salt. I personally think that’s freaking dope. If we had that we wouldn’t have a water crisis
@@kmanccrso you think ocean fish drink fresh rain water?
@@codycast No but the salt isnt removed from the ocean... ie they aren't desalinating the ocean are they? they put the salt back into the water. I guess what op is getting at is how their kidneys regulate salt and remove it from their blood and to replicate that process at scale.
@@codycastDo fish drink at all? Can it be called drinking when your entire life takes place fully submerged?
Edit: looked it up and answered my own question. Saltwater fish do drink because the salty water draws water from their less salty bodies. Freshwater fish do not drink however, their bodies are saltier than the surrounding water so they hydrate by osmosis.
I don't know if I agree with that last bit at the end about having the private sector do it. Private sector is out for profit, and do we really want profit driven companies to control the basic necessity of fresh water?
One of the most interesting things you can see is where a fresh water river flows into the sea. From overhead, you can literally see the boundary between these two different sources of water as they mix.
It is worth noting that the conditions in sea water intake vary day by day and even during the day. So conditions in a desalination plant have to be monitored closely in order to ensure efficient operation and a good product at the outlet.
I think such a boundary is called a halocline, iirc
In some places, they have plants that win energy from this mixing, sometimes called "blue energy". This clearly shows it takes energy to get the salt out.
ok
(Literally)
I really love the information you put out here. The only point I disagree is the privatisation of water treatment. Companys and investors deciding prices for drinking water after contracts have run out. There have to be other ways for water desalination or use of water rights.
Exactly. Privately-owned public utilities is a much greater evil that he realizes. But he is extremely didactic when it comes to explaining engineering & chemical situations so I shall continue to subscribe. And that (misguided) statement was a very small part of an otherwise tremendous video.
It's pretty frustrating. How does the private company compensate for the risk? Why, by charging more than it would ever cost! Governments are big enough to compensate for that themselves, *without* also needing to compensate boards and shareholders.
@hairymcnipples no they can't. Governments cannot effectively allocate resourcesb
@@hairymcnipples the problem isn't risk but lack of competition. It's usually hard to have multiple infrastructure providers in a location in a reasonable way
The contract could be for a certain percent above cost for the lifetime of the plant. The contract just needs to be written well. There may be cases where a local government simply can't afford it, or it doesn't make sense for one reason or another. I agree that allowing private companies to control it is an issue, but if well controlled by the contract it shouldn't be a problem.
I lived in a small Florida gulf coast city for years and this is how they got their water. It was very good. The only time I noticed a difference is if we filled the bath tub - the water had a greener appearance than what I was used to seeing in other cities. But again there were no taste or other useage issues for us.
My god. That's such a turn off!
Idk how you drank the Florida tap water. 🫣
@@ohio_dino Simple, it's cheaper than bottled water and isn't unsafe to drink. And in the past, it was the only game in town, as commercial bottled water on a wide scale is actually fairly recent. As in, I remember when bottled water was becoming common, and I am not old. More often, you would have water distribution stations where you put in say a quarter for a gallon of actually fresh water, which would be poured into the jug/bottle you brought with you, of paid extra for one to be provided for you to be reused. This was, and still is, common in places in the US where the tap water is of dubious quality and safety for consumption despite purification work.
There are regions in this country where I will not drink tap water because of that. Most are in the Midwest, where local corruption actually made the water dubious to drink at the best of times, courting poisoning from industrial runoff or typhoid at the worst due to the ones supplying the water not investing properly in water purification, or keeping the systems well maintained due to taking the cheap route and pocketing the difference when they aren't outright embezzling the funds. A good bit of advice is to ask the locals if they drink the local water, and to generally not do so outside of major metropolitan areas anyway. What's good for general use like washing, bathing or showering, is not necessarily something you may want to drink. And yes, I am talking from experience here. Far less of a problem today, but it's still there.
All it took was getting typhoid once to learn that lesson.
Desalinated water, depending on the desalination method and the plant, can have a vastly different flavor profile, when it actually has one, than what most of us are used to, though. And the slight green coloring may have been a dye so you would know the water was safe to drink.
@@jgkitarelman… it’s insane that a highly developed country such as the US still hasn’t got some sort of national initiative in place to provide equitable access to drinking water.
I ran evaporators in the Navy and drank the water for many years, it was pure enough to run through the boilers without building up excess scale as well. Tasted great, and made a mean cup of coffee.
So?
@@whosjulez1157they were commenting on their experience with desalinated water. It pertains to the subject.
I was in the Royal Navy as an engineer and worked extensively on desalination and distillation equipment. After leaving I travelled as a civilian desalination engineer....brings back memories..
On looking back on this video today, what it highlights to me is that we need to seriously need to care for our present Reserves of water, surface water to ground waters, don't have fracking anywhere near these water reserves....
Thom in Scotland.
Why? Desalinization is easy
@@Marcus-p5i5s
Desalination has been around and know of for some thousands of years, easy might be your take on it,. Expensive would be my take on desalination......And .... Fracking pollutes surrounding waters, and ground above and below surface.... To be avoided.
Thom in Scotland.
WRONG!!!!!!!!!!!!! It isn't a fcking "take". It is scientific REALITY. Rent an IQ@@fuelban
@@Marcus-p5i5s
You do not explain why, you consider desalination ( EASY ) ... Your being quite cryptic ..... So ....
Thom in Scotland.
I live half a mile from the Carlsbad plant. Thank you, Grady, for covering it! It’s been an excellent resource and source of pride.
ok
If you found out how the private company pay fines for dumping chemicals and paying off employees you wouldn't be as proud. Its a real dirty job and cutting corners in a hands on job like this puts people in danger who work there. Great source of water though...
Who is Carl and why is he bad?
@@youtubezombiesNono, you've got it wrong. It's possessive, they just removed the apostrophe for logistical reasons. It's actually Carl's bad desalination plant.
Interesting video, I did some work (electrical distribution/transmission) related to the USBR’s Yuma Desalination plant. It’s purpose was to reduce the salinity of agricultural drainage water before it was put into the Colorado river to aid in meeting the requirements of the Colorado River Compact treaty obligations with Mexico.
In addition to the thousands of of plants on land around the world, there are thousands more because almost every naval ship and probably most commercial ships also use desalination to provide most of their water needs. The 30 year old ships that I served on had some nasty water, but it was drinkable (barely so) and the salt levels were low enough not to mess up your bodies balance. That was in the 90s. We also got tons of bottle water training in the middle east which was all desalinated. Those plants actually made water you could stand to drink.
P.S. I love the eyeballs on the reverse osmosis machine. :)
I was on the Enterprise, which at the time I was onboard was over 30 years old. But our water was better than the tap water here in Las Vegas. Hard water is the worst. Of course I drank a lot of soda in those years which helps with the taste, but I drank tons of water from the drinking fountains because you have to working in the engineering plants, I don't remember it tasting bad. And of course the soda we got in the middle east was also desal. water.
@jimmym3352 I generally don't do tapwater unless it's fileted anymore. Even in small town USA you never know what's in the water until after its to late. Just like Camp Lejeune and Flint MI. A small town near me had some carcinogens above acceptable levels for over a year. No one knew until the water department sent out a letter saying it had been cleaned up. I assume you are a sailor. Semper Fi brother.
@@curtisroberts9137 water quality where I live in Australia is sometimes rough as well, I was supplying rain water to a couple of friends' families in the late 90s and early aughts because they were constantly getting sick otherwise, it's gotten better but still had times when a whiff of the water has been "I'm just not going to shower for a few days"...
@@cericat I had an aunt that lived in the mountains of Colorado. Their well was all mineral water. Smelled of sulfur most days. Lots of 5 gallon jugs of drinking water delivered there.
I lived in the desert for 25 years. In that period I build very simple solar distillers that delivered less than 1 mg/l total dissolved solids. The feed for my stills were about 2500 TDS. All the water I drank at my home (that really is almost all) came from these stills. There were a few technical improvements in building them but it is possible to produce drinking water (and even water for laboratory use). The problem is that people need to use saline water for a number of purposes rather than purified water because solar distillation gives really pure water but great enough in quantity not in fire fighting or irrigation. When I see this, I realize how primitive our society's understanding of water chemistry is.
During the "Millenium Drought" in Australia the NSW government funded an RO desalination plant to supply 15% of Sydney's drinking water with provisions built so it can be easily scaled to supply up to 30%. It's energy needs were offset with a massive new windfarm just out of Canberra.
The plant was finished in 2010 right as the drought broke, so it was mothballed and wasn't used until the 2019 drought
There's a heap running in the other states except for Tas. And of course Toukley planned but deferred back in 2007 in our case. We really do need to reconsider them in NSW since Sydney's water demands can cause difficulties for other catchments, and also to support some of our ag needs rather than impact the regional water supplies.
Perth gets about 50% of their drinking water from our desal plants
@@kevinrudd1 not just Perth, you send a lot of water inland via pipeline.
So das the desalination basicly work energy storage for the windfarm?
This channel is one of the most exact, simple; direct, and factual out there for understanding technical topics. Brady covers everything from catastrophes to fundamental physics, in a most eloquent and _practical_ package. Without any pretense to be the most 'scientific' of its kind - yet it manages being most accurate, with hardly any errors or discrepancies on its formal concepts. Something that very few channels and media can claim to nowadays unfortunately. There is so much to be learned from this content... and the exactitude of concepts with simple and clever demos; is just admirable.
There is so much engineering and physics content out there, but few are this earnest; and simply true. Fantastic stuff.
Distillation can be a lot cheaper, especially considering it doesn't need to worry about all the other purification and waste disposal steps, once you remember that you don't even need to boil water. It only needs to evaporate. Small quantities of water in a thin film on a warm surface evaporate easily. It's actually super simple for individuals to distill and condense drinking water. It's only difficult at scale.
Yes, I'm that guy. "How hard could it be?" Thank you for explaining how hard it can be and the energy costs involved.
A big chunk of the energy costs are from chemistry/physics constants like the heat of vaporization of water. If you want water to change from a liquid to a gas that will be 2.2kJ per gram.
This is part of why reverse osmosis is more efficient, it doesn't involve boiling the water but will instead have other costs. (Like the energy input to pressurize the water, pressure can be considered a form of potential energy.)
What's interesting is this is the exact opposite of making maple syrup. Both distillation and reverse osmosis are options available to producers. But, in the distillation process, they keep what's leftover in the pan after most of the water has boiled off. And in reverse osmosis, they keep the discharge and reject the fresh water.
Possibly sell the waste water from the sirup process as sweet water, naturally flavored.
@@world_still_spins You can sell the unboiled sap for more. It's eminently drinkable right out of the tree, and the trace minerals are believed to have health benefits. Also, if it's still sweet after RO then you're doing it wrong.
So your saying we can solve the water crisis with mass scale maple syrup production
@@oceanceaser44 May not be impossible. There's new tech now that coppices maples, then applies a vacuum pump to the saplings/shoots to extract the sap. Still very new, but apparently very efficient for sap production. If you can get the tree to grow, then it can produce a lot of sap from sub-optimal water sources. The caveat is that it's only in certain climates, and only in the spring.
@@bobcostas9716 yeah, but this syrup is imported wildly to Europe and it is disgusting, very poor quality compared to 'classic' syrups. I am not sure if this is caused by the tech or that they just settle on lower grade syrup.
Yesssss finally, I am obsessed with this topic..... We need a way for clean drinking water in the future that is cheap and easy
I have a small wall mounted ultra pure water distiller that uses a flash evaporator in the sense it throws spirts of water on a hot plate. It makes 5 gallons per day and draws less than 10 amps 120v. Pretty neat but super expensive.
One issue with privatizing the production of drinkable water is that it gives private companies a lot power over what's essential to live. They could, on a whim, raise their prices and the state (ultimately, the people) would have no choice but to pay. And there wouldn't be much we could do about it.
Private companies have profit in mind instead of public service. Which should be the core goal of utilities.
Question: How is that any different from a government being in complete control over the water supply?
@@rosskwolfe The question should rather be: how is that in any way similar to the government being completely in control?
A State is not a company, and should at no point be run like one. (Looking at you Macron.)
Basically, a State making money is failing at being a State. Whatever money it makes could (and should) be reinvested into public services. But even worse than that, a State making money actually fail at enabling the creation and sustainment of companies.
The whole point of a State is to enable fairness on many topics. To provide for the unlucky few by taking from everyone. To prevent a lucky minority to gain too much power and control.
At no point in time is profitability even a question.
So yeah, I'm asking again: what would be similar?
@@rosskwolfe Because it's a captive market which is prone to abuse, the market corrections are not available but with government run the corrective mechanisms are still present. It cuts out a layer of profit making operating costs lower. The government generally has to pick up the bill if it fails anyway whereas shareholders are never held to account for running the company into the ground and skimping on maintenance while walking off with the dividends (looking at you UK privatised water companies).
@@rosskwolfe
The government wants people to live and you have a say in the government. Don't ask questions like these anymore.
True but if the problem is huge enough, government could essentially regulate it and the company have no choice but to comply. They of course go out of business if the regulations made it unprofitable. In the end the technology will be developed as long as there are incentives, whether it's profit or public needs.
If you can't source locally produced natural seawater, homemade is fine too
How much energy does it take to separate humor from engineering?
@@BS-vx8dg Less than it takes to artificially inject humor into engineering. ;)
This is a video I didn't expect, I had to instantly watch it.
I've been working with membrane desalination for a while and it looks super simple but under the hood, reverse osmosis still looks like alchemy. Thanks for the video!
18:43 That was one Very Slick Commercial...lol. You should go into Television because I never even felt the "Prick" until it was over :D
Great Video though. I learned A LOT, Thank you
Thank you, the camera shots, narration and editing are perfection. The small scale examples you built are a fun little break from other channels summed up wiki info dumps 👌✨
Hey Grady, I really appreciate the content you bring to UA-cam. I'm going back to college to be a mechanical engineer and you've inspired me so much.
Grady is a civil engineer
Worked in the water treatment - specifically deionized water - industry for 20y. Ive always thought this technology was just on the edge of becoming a significant supplier of potable water for the world. Thank you explaining why we are still strughling to get there. One thoight ive had is a desal/power plant combo - use concentrated solar energy supplimented by a modular nuclear power plant (boiler water only of course) to convert salt water to steam to power turbines producing energy and the resulting water then is further processed to potable. Removing the salt deposits would need to be mechanical and designed into the boilers to be efficient i would think. Very interesting and pertinent topic for the world
Protect this man!
Steam turbines run on superheated steam 500+C You probably don't want to heat your potable water to that temp for efficiency. Just run the solar concentrators it'd be cheaper to just build more of them and run when the suns out than it would be to build a nuclear plant and a conventional RO for backstop. The nice thing about water is it's relatively easy to store for long periods even over months or years. Not hating on nukes but you might as well take the energy from the sun when you can store your output easily.
Add to this the potential use of the by-product. Just keep increasing the salt-to-water ratio and you could potentially have an alternative to the salt mines
It surprises me we can't do anything with the waste brine. It feels like it should be usable in salt harvesting fields or for other uses of sea water. I'm sure there's good technical reasons. Just hope we can overcome those technical issues and use that concentrated brine.
That much brine would be pure poison anywhere but the ocean.
Not sure where the Middle East desal plants expels it but I'd guess it's far from the intake pipes.
Also, in the maritime community the operative statement is "The solution to pollution is dilution."
A really interesting video showing how complex the workings of desalination plants are,I learned a lot about how little I know about this process,but great to watch and come away with a bit more knowledge.
This is really high quality, highly informative and professionally narrated content. Hats off to you kind sir, for summarization such a complex subject while still keeping an objective stance on the matter. Really, really well done.
⭐
Thanks for the great video! I learned a lot about the challenges of desalination, but I dont agree on your take on private-public-partnerships. A private company would not agree in a contract if they wouldnt make profit out of it, so in the and such an agreement is more expensive either for the government or the consumer. Also the point of not having to take the financial risk isnt true in reality, because in the case that there is no other way of getting drinkable water (which if I understood correctly is the only reason why you would use desalinated water anyway) the government would have to save the Company financially to keep them operating, because it is no option just to not produce drinking water.
Search for: spacex cost vs nasa
"A private company would not agree in a contract if they wouldnt make profit out of it, so in the and such an agreement is more expensive either for the government or the consumer."
Thank you! I had scroll way too far in the comments to find someone else mentioning this. Privatizing water is a recipe for disaster.
desalination is also done with another phase change: freezing.
the most common is the 40 stage flash desalination, where the evaporation enthalpie is reused 40 times.
besides reverse osmosis, there are others.
You neglect that the reduction of alkalinity in the seawater from PH 11 to 8 is the dissolved CO2 in seawater.
Important because this gas must be removed to have acceptable heat transfer in the heat recovery condensation surfaces. Your oversimplification has consequences
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Thanks for the informative video. I have worked offshore for years and we always use vacuum distillation or RO to produce water for the living quarters. It's funny when you tell new people that the delicious soft drinks from the soda fountain started as seawater from the Gulf of Mexico that morning.
Great video, but I dissagree on the topic of running the desal plants by private companies instead of governement run. It is usually much more expensive because the private companies try to maximise their profits. Has been a problem with several of the formerly state owned infrastructure here in Germany, e.g. water system in Berlin: it had gotten much more expensive since the government sold it (in 1999, 49.9% of it) to make a shortwhile income. Since the buyback (2013) of the water infrastructure, the prices went down again.
While I agree that utilities run by private entities can be more expensive since my town's electric division has significantly lower rates than the surrounding towns and cities here in the states. I think the point was that smaller towns/cities (large enough though that can still afford desal plants ofc) might not have the money/time/personnel to manage the utilities which may cause it to actually be more expensive. Also, privately run utilities can allow for more innovation; Possibly driving prices down through better efficiency.
@@xing3240 It doesn't make any sense. The costs of running it are what they are. Either you just pay that cost or you pay that cost PLUS the cost of whatever profits the private entity is seeking. The math is simple. Also there is tons of data showing how profit seeking get's in the way of innovation. Innovation has happened despite profit-seeking not because of it.
As a labprofessional I will just copy that sand-in-pot approach for my garagelab.
It`s quite smart since its realy stable in holding the temperature.
Lived on the island of Aruba for 11 years off and on. Their water came from the Balashi Desalination Plant that was powered by the Lago Oil Refinery nearby. The water was filtered through large pieces of coral to give it minerals. A Balashi Cocktail was a glass of water. Balashi Brewery is a local beer brewed with the water.
@17:38 the problem with that is: How many corners are the private companies going to cut, w.r.t the environment and how much oversight and inspection is needed?
I agree whole heartedly with this sentiment.
It's amazing how much harder it is to desalinate water than it seems like it should be
Well it’s easy to dissolve salt in water, and removing it is the reverse of that
I'm a chemist. It seems like it should be really hard, and it is. You're fighting both entropy and enthalpy.
it's actually really easy. Collect rainwater. Done. but of course he didn't bother to cover that method.
@@SoloRenegadeHe explicitly noted this option in the video
@@nahometesfay1112 why didn't you give a time stamp? where was the discussion on how to implement it, on how it works, etc.?
At 14:30 he INDIRECTLY mentions rainwater, but not rainwater collection. He's referencing ground water, lakes, and rivers.
"if mother nature isn't dropping enough water for your particular area"
this is wrong, and demonstrates his lack of understanding of rainwater collection and how it's done in such an environment.
You had me until the last bit about private infrastructure. It can work, but not without heavy regulation and oversight - which something that is always argued against when things are privatized.
I would highlight the issues the UK is currently facing with private ownership of the water industry.
Dwr Cymru / Welsh water are doing fine as they are a not for profit company.
I know Thames Water supply a lot more people but it is in a very concentrated area. Lack of investment and upkeep seem to be the major issue and the fact that they have to pay shareholders just means they have not invested enough to keep the system working.
So the choice seems to be....gov buying them out with tax payers money that will go straight to the shareholders while the rest of us are paying higher taxes to pay for the lack of upkeep :/
Thanks, Lenin
@@vacamike how childish
@@KirstyTube they too are doing lots of sewage dumping unfortunately, though not the worst
@@soupsoup6813 yeah- looking to tax money as a savior is childish
Also there is the issue of biofouling where bacteria grow on the membranes and clog them after a while. It turns out to be very difficult problem to fully address.
Slow sand filters, followed by UV lamps, then activated carbon filters.
@@Simple_But_Expensive $$$$
@@thejman5552 His user name checks out.
@@bradley3549 Lollll
Just add salt to kill the bacteria
I'd like to know why the "Ocean Vapor Towers" approach doesnt make more sense than these methods, it seems a logical way to get fresh-water from salt-water and it leverages cycles so nature is doing a significant chunk of the work
It's slow per liter of water treated compared to other methods. Thus for a given amount of water the equipment has to be MUCH larger. (more expensive)
Basically scale, the number of towers you would need is astronomical
construction cost vs output. running cost isn't everything
At that point you're basically engaged in a small geoengineering project since you're trying to change the local climate and that is basically impossible to predict because you have to factor in the entire global climate to figure out what will happen. No one in their right mind would sign off on spending millions on a project that you can't even guarantee the outcome of. If a region doesn't get a lot of rainfall then there's some pretty powerful natural forces behind it and it's fairly easy to conclude that humans can't easily influence that. Like climate change is only happening because our entire global civilization is engaged in the same activity and has been doing so for about two centuries so it really isn't easy to influence the climate of our planet.
Also there's the fact that you can't necessarily directly use rainwater, we usually use groundwater which has spent thousands of years filtering through the ground to make it clean. Plants that draw directly from sources such as lakes and rivers still do need some amount of cleaning before it becomes safe to drink and it's susceptible to ground pollution, which an area that experiences little rainfall that would normally wash it out probably has a lot of.
Based on this video it seems that reverse osmosis is a *lot* more energy efficient than distillation. It may seem attractive to use sunlight directly for evaporation instead of electricity. However, if sunlight is plentiful it might still be more efficient to convert that into electricity and use it to run reverse osmosis.
The problem with private sector in this case is that there are many incentives for cutting costs and leaving the impact to the future generations
Grady, it might be interesting to do a video on how drinkwater is made in the west coast of the Netherlands. Here the regular groundwater is too brackish, so we combine rainwater with river water by pumping it into our sand dunes, where the sand naturally filters it before we pump it out of the reservoir underneath the dunes.
He will never read this.
@@andybaldman You never know, he might scroll through the comments.
@@andybaldmanyour comment, sure. But his comment? Maybe.
Thats interesting!
@@andybaldman What does that kind of comment accomplish?
Here in Israel we have gone from constantly worrying about getting enough winter rainfall to fill the Sea of Galilee (misnomer, it a freshwater lake and serves as the country's water reservoir). Now with several RO plants built, we have enough water for domestic usage plus use the desalinated water to refill the Sea of Galilee if it gets too low as well as transfer water to Jordan.
That's because you have lots of oil there so the cost of RO treatment is much lower since the most significant cost is usually energy.
actually, israel is one of the few countries in the middle east which doesn't have oil.
@kaiqiwei3628 The majority of our electricity now comes from the offshore natural gas, replacing coal
@@adid Yeah, we did have in the Sinai but gave Sinai back to Egypt as part of the peace agreement.
No wonder Jesus could pull off the scam of walking on water, because he found a sand bank to stand on.
It would be cool if you went into more detail on the energy recovery systems in RO. Rotary pressure exchangers (one moving part!) are remarkable devices -- and they were invented surprisingly recently.
Also, for distillation, I think you're showing a humidification/dehumidification system there. The water vapor is mixed with air. With these, there's a problem with mass transfer at the condenser: the air near the condenser surface becomes dry, and water from the rest has to be transported through this boundary layer (this is not a problem in a vacuum system where only water vapor is present). There was a spinoff from MIT a few years ago that had a new condenser that gets around this problem (bubbling air through trays of water; the bubbles are tiny with large surface area.) I've thought this bubble tray system was quite clever. These were using it to desalinate produced water from fracked wells, reusing the water for more fracking.
Another potentially interesting concept: if you keep increasing the salt-to-water ratio in the bi-product, you could potentially end up with an alternative to salt mines.
@@TheExileFox Yea - sea salt also naturally contains bromide and iodide compared to rock salt.
@@TheExileFox I think salt isn't worth that much. 1 ton costs arround 300$
It is also not that much. He said sea salt is about 35g per litre , if I rememeber correctly.
Can imagine that "harvesting" and selling this salt is more expensive than just pushing it out into the sea before it solidifies.
Yes, he skipped or ignored a few methods, including rainwater collection.
I noticed but then he said SIMPLE, so it is not what you would build for real.
love that you did an experiment demo and didnt just talk about it. the scientist in me loved it.
This was interesting. As a dialysis patients I actually have a water system that starts with two carbon pre tanks and an RO that is about the size of a large computer tower in my home to make medical grade water. Running it about 100 hours a month doubles the household water use but is not that hard on power. The equipment does need to be replaced/refit once a year but the healthcare system pays for that so I have no idea the cost. The tech seems to be there when you need it to live. I think we just won't improve it until there is more money to be made.
Environmental engineer here. It really is not that hard. It's just that it requires a lot of energy. High pressure pumps need a lot of power to reach necessery pressure level 100+ bars, so that desalination (reverse osmosis) membranes let H2O molecules and nothingelse through.
As always, your videos give great insight to the engineering nuts and bolts of the subject matter. Keep up the good work.
There are quite a few desalination plants in the Cyclades in Greece. For example, the little fresh water that the island of Syros (about 20000 people I think) goes towards things like the hospital or the production of a local traditional product that needs good water. The desalinated water isn't usually drunk though.
Great video. We can look at it the other way too. How do we use less water. This just goes to show how much effort goes into creating something a lot of us take for granted.
Watched this yesterday on Nebula -- I always knew in theory how reverse osmosis worked, but I'd never actually seen one of the membrane tubes. Very cool!
Water conservation methods are often more cost effective than desalinization as well. A municipality can spend a lot of money fixing leaks and implementing water saving policies before you get to the point of using desalinization.
Especially in places like california where it actually rains a lot and they just don't have the infrastructure to store the water
You can also implement grey water systems to help save the actually important water. We use water on a lot of things that don't actually need to be of human drinkable quality such as toilets and watering plants, there's no point in these systems using the expensive and rare freshwater and instead they might as well use waste water from other processes or water from less clean sources. You can implement this both on a municipal level and a private level, ie. in your own house you can have your toilets reuse water from the shower or washing machine while on a municipal level grey water can be reused in industry.
I just love the conclusion. "Let's privatise the water supply and all the issues become SEP."
I recall reading about a mechanical technique for desalination a while back. (I think it was an israeli paper?) The idea was to lift a column of water in a sealed tube as high as possible until the weight of the column overcomes the air pressure and the water stops rising, forming a vacuum on top. the vacuum fills with vapor which is then forced out through a one way valve as the column compresses and the falling column which is still mostly liquid water can be used as a counterweight to raise another column. With multiple columns you can create a desalination engine. I'm not sure how this method compare to the membrane approach, but it would be interesting to see.
The little experiments are so fun to watch. Love it
Grady, Have you heard of "Cryo-desalination"? It seems to make sense for areas that regularly see freezing weather. What are your thoughts?
17:43 Lost me ad clearly advocating to privatization which results in deregulation as the private entity captures more and more of the revenue that would be going into public infrastructure and finds that the cost of lobbying is lower than the cost of compliance.
Mmm. PFOAs and agriculture runoff at consistently higher amounts than allowed with no meaningful consequence… yum.
If the state could handle any kind of business the Soviet Union wouldn't fail, Brazil would be the richest country in the world
Public services sucks
This is fascinating lol. Have seen enough dialysis processes but never thought about using the same filter to desalinate water. also the insane amount of engineering behind an everyday essential ☠️
You didn't even count the energy cost to make that ice tub :). Thank you again for making these incredible videos. Learned so much from your channel. Have a nice day!
He wouldnt need the ice tub if the pipe with clean water would just be long enough.
One advantage of desalination is that it can be coupled with solar energy production, when there's a lot of solar energy, the plant can ramp up and produce a lot of desalinated water for later use with the cheap solar energy and at night it can be shut down and reduce the energy consumption when there is less power available. There is also a long term correlation, during the summer when water consumption is higher also there is usually more solar energy available.
you can also store that water long term too. You can produce it in summer and consume it in winter if desired.
There's also concentrated solar plants, which use steam turbines to generate their power. You could create a combined distilation desalination-CSP plant and generate power and drinking water at the same time. (I'm surprised this isn't already a thing)
Use boat with solar panels and kinetic energy things
Combined with windpower and biogas.....yes it makes sense.
I’m an engineer on an oil tanker, we have an evaporator. We use heat from our main engines cooling water. And an ejector pump to create a vacuum, fun fact. Water boils at a lower temp while under vacuum. Our water is usually 1ppm salinity.
Amazing technical and practical analysis of desalination! I live in Arizona. We have abundant energy in the form of sunshine and wind, lots of open space, fertile ground for growing crops, but we lack sufficient water to continue growing more food and our population. Your timing on this video is amazing because I was just sitting down to research this topic myself so I could do some writing on the economics of desalination for our state using water from the Sea of Cortez. Your video is a great place to start and really whet my appetite to dive into total energy cost per volume of water generated, including pre-treatment, desalination, consumables, pumping and any post-treatment that would need to be done if the water was used for drinking.
The interesting thing about our situation here is that we could easily provide drinking water to many more people in this state if we used all of our reservoirs for drinking water. Where we run into problems is with water used for industry and agriculture. I think that it's inevitable that we'll ultimately use desalinated water for industry as the benefits of agriculture and manufacturing here in the state are greater than the drawbacks, such as the need to use processed water. But that case remains to be laid out clearly....