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If you drink beer try to get a few cans of Windhoek Lager, which is a beer that is actually brewed from recycled sewage water, at the brewery in Windhoek Namibia. The town recycles sewage water into drinking water, mostly because it is situated in a large desert near the ocean, and desalination, and bringing in water, is expensive, so recycle it is. The one thing it does have in abundance is sunshine, so it is easy enough to at least use solar power to heat your household water, though the region is not called the Skeleton Coast for nothing, and it is the corrosion capital of the world, with salt spray and fine sand, actively working to remove protective coatings off metal.
its crazy that waste water treatment originally began as brewing ale, beer, wine, and so on as a clean, and comparatively safer alternative to what was back then a very unpleasant "fresh water" source, drinking booze way back actually prevented you from suffering all kinds of diseases from e.coli to malaria to parasites to bacterial infections, and while today liquor is mostly seen as just a vice or past time, it really was essential for survival in ancient times. especially since ale and mead was more nutritious than most food of the time available to commoners.
I spent a couple of decades as a wastewater treatment plant professional. Retired now and one of my hobbies is home brewing. All that time in the lab must have been somewhat enjoyable for me to consider brewing an option for a hobby.
@@jiveturkey9993 Some of those fish farms in Asia have actually insane water treatment systems for the fish because they literally pack them in the farms like how we used to chickens in the US. The water has to be constantly cleaned and aerated to make sure the fish and bacteria are able to breathe, clean up waste, prevent Ammonia buildup.
@@ramses6163 Any entry college biology courses, or appropriate trade schools are good places to start. Many countries have dedicated water treatment operations courses that can be started online. Check out your local government or college websites for possible information. Also many employers have on the job training for the promotion of in house employees who want to improve their skills. Good luck!
I love how you can combine a liquid that's the combination of people's waste and a liquid that makes people wasted in one video and make anyone feel interested in it.
@@PKMartin And just to get even more circle of life, the yeasts consume sugar from the apple juice and pee out alcohol, so we're consuming another organism's waste for our fun and delectation.
Grady, you were basically smiling this entire episode. Your ability to transmit educational material to the youtube masses with such enthusiasm is so energizing and contagious. You can really tell you enjoy learning just as much as you enjoy teaching. Also congratulations on your new one!!!
I currently work for a municipal water utility in the wastewater department. When I first started working here, they took us all on a field trip to one of the treatment plants. The plant manager bragged on the plant and said, because of the organisms, he felt more like a zookeeper than a sewage treatment plant worker. “Gotta keep ‘em happy!”
I love that in every video, there are techs and engineers who work and specialize in the topic in question. Thanks for doing your part to keep the modern world safe and running smoothly.
A few things to note to the more curious: 1. While we do pump a lot of Oxygen (or just air that has 21% Oxygen, since it's free :P) into the tanks, not all steps/tanks are aerated. Most notably the Anaerobic (for removing Phoshorous) and Anoxic (for removing Nitrogen) tanks are mixed without aeration. 2. BOD is still used today, though nowadays COD (Chemical Oxygen Demand) seems to be more preffered afaik. Though personally I still use BOD most of the time. 3. Nowadays, systems like MBBR/IFFAS are becoming more popular as they require less space and air, and are more efficient. The TL;DR is that in the tanks with aeration we drop tons of small plastic chips on which the microbial colonies later grow, which in turn increases the dencity and speed of the biological proccesses. This/ along some other things make the system more complex. :P 4. One of the big problems that remain, is how to deal with the excess sludge/biomass that is produced on a daily basis? Sure, we prevented it from reaching the downstream water, which is good, but what to do with it now? This is a big topic in itself, and one that is still developing right now.
About point #3, how difficult is it to remove the plastic chips added/what happens to them? Also adding plastic "confetti" for microbes to grow on is one of the problems caused by microplastics in the ocean, do you know if the treatment method is inspired by this problem or if someone from the treatment industry had an "oh shit" moment about the plastic in the ocean?
@@randomfastreader The waste treatment department in the city where I used to live sold the dried solids as fertilizer too, although they cautioned people to not use it on anything that was going to be eaten. Their biggest concern was toxic metals. For a while a common prank in the city was to buy some of the fertilizer ($5 for 100 pounds) and spread it on someone's lawn to spell out rude words.
Even before watching the video, and being in wastewater I glad you are covering this! Duality of life, one man’s trash is another organism treasure (aka food) and vice versa. The many wonders of life and how every life form is engineered to balance each other. Great video! On a side note a lot of my former coworkers in the industrial wastewater are great at brewers. Some even culture their own yeast.
Well, both have the same function, make water transform into a drinkable liquid, by using a bacterium or yeast to outcompete the bad bacteria or yeast, so that they die out, leaving only the desired microorganisms around in the massive number, that ensures there is only a monoculture there, cleaning the water and making it safe to drink.
A nice "Addendum" to the sewage series would be how it's treated on the ISS, since most of ground-based treatment involves gravity which the ISS can't really take advantage of.
@@DrewNorthup You described how the solids are disposed of, but I took the question to refer to the process of separating the water and solids, in the absence of gravity.
Grady, I work for a construction company that specializes in water and wastewater treatment, and i must say, i thoroughly enjoy all your videos on the topic. Please feel free to reach out anytime if you feel you ever needed additional information for these videos! Keep up the good work!
This was a really interesting video for me, because not only do I like an occasional beer or especially cider, but I work in a plant that uses recycled water! We make brown paper (linerboard or containerboard) from recycled corrugated boxes (aka OCC). The process uses a ton of water to break down, refine and store the paper pulp. You can't pump it if it's more than 5% paper, so that means every tank has at least 95% water in it. And it's all sort of dirty water with fine particles and dissolved solids. But we also bring in 100s of 1000s of gallons per day, as well as discharging to the city after treating and going through our own clarifiers. We also monitor temperature, pH, and flow (instant and total). We're allowed to take a certain amount from the river on our property, but the remainder of our water use is supplied from the city waste treatment plant. Effluent quality water is piped up to us (about 3 miles) and we use up to 1000gpm at times. The pipes, the tank, and the pumps are purple. There are also some purple fire hydrants that I don't recommend playing in when they get flushed out. Thanks so much for this video, really enjoyed it. --RB in CT.
When the news gets me feeling down, there's nothing quite like a glimpse of human ingenuity to help me feel optimistic again. Thanks, Grady and all innovators working to make the world a better place.
Before I became a operator I was interning at a brewing company for my degree and never once did I think I would correlate to my current career as a wastewater man. Great vid!
Good stuff, as always. I wanted to pitch an idea for a future topic: landfills. Would love to learn more about the engineering and science behind construction, site selection and functionality.
Been years since I've interned with the MWRA and I've never seen that view of it before but that initial 5 second shot looks like the digester eggs at Deer Island Waste treatment facility in Boston (should be Logan right there in the shot too). It was a pretty cool experience seeing how all that worked and I also learned that part of the sewage in that whole system gets turned into fertilizer
I used to work next to an active demonstration sewage treatment system and after that experience I would say that your neighbors thank you for not replicating it in your garage. This was a museum where the entire second floor's wastewater was treated in one of the exhibits (but then secretly sent on to the sanitary sewer). On warm summer nights the smell was quite strong, even for such a small system. We also had the largest roaches that most people have ever seen!
I love learning from you. You're thorough and enthusiastic, as well as kind in your explanations, and though you never dumb down, you always manage to explain everything in terms we can all understand. Your enthusiasm is so contagious, too - I enjoy learning about the world around us in all sorts of ways, and your videos are definitely top of the list for infrastructure and engineering. Thanks so much for taking the time and effort to make such enjoyable and engaging content!
I almost always skip thru the commercials and sponsor's message on YT videos but your family keeps me watching. That handsome little guy is an excellent helper. Your whole meal prep situation is almost identical to mine. Keeping those toddlers busy is THE challenge, yeah?!
This was a fun video to watch! I'm a starting homebrewer myself, focussing on beer. This is the first time I've heard that yeast would stop producing alcohol when exposed to oxygen. Anaerobic processes is a new thing I've leared today. Thank you!
AFAIK, you should only leave a bit of air at the top of the container when fermenting most alcohols. In fact, I was worried about too much air in his fermenter. Mind you, I'm a novice at this, still. Don't take my word as law.
I have a degree in food science with an emphasis in brewing. You absolutely NEED O2 to get your yeast going. Without going into complexities, yeast are not strictly anaerobic. If you didn't have any O2, then fermentation wouldn't probably be as vigorous as you'd want and/or wouldnt begin much at all.
@@kirkgoingham6095 But you have to oxygenate the mix at the beginning (by shaking) and then let it be in the container with as little air as possible, right? After the initial step, I always heard that you have to try to introduce as minimum air as possible. Please correct me if I'm doing it wrong.
Exactly! 99% of the time in home brewing transferring your wort to your primary fermentation is enough exposure to air for your brew to turn out great. Or, if you wanna be extra careful just leave the airlock off for a little longer. Everyone has their own rituals lol. And, yeah, try your best not to reintroduce air because that will slow down the metabolic pathway yeast use to facilitate alcohol production, but nothing's perfect in homebrewing, especially when you transfer into a secondary. You're gonna get air, but as long as you plug that sucker up, you'll be fine!
@@kirkgoingham6095 yeah before the yeast is pitched we usually shake the vessel and aerate with a whirlpool paddle to get some 'starting oxgyen' for the yeast to grow.
Would love to see a biosolids removal process video next! We typically land apply our sludge, but haven't needed to in years. It would be neat to see land application vs. drying, and other removal options compared in a video. Good stuff as always!
A good overall review for the general public on wastewater treatment. Obviously there are many other issues that must be addressed in design of facilities but that is what trained engineers are for. In my 38 years of consulting practice I designed countless waste treatment facilities (mainly activated sludge but some trickling filers) for both municipalities and industries. Everyone was a learning experience and over my time we went from mainly secondary treatment reducing solids (TSS) and BOD to first converting organic nitrogen to nitrates in the nitrification process to removing almost all nitrogen and phosphorus by additional techniques also. Sometimes the regulatory agencies required such low effluent concentrations of these parameters we had develop tertiary treatment steps or enhance the secondary processes to increase removal rates. Industrial wastes could be especially troublesome due to presence of toxins but these could be successfully treated individually prior to discharge to the downstream treatment facilities. At the time of my retirement new issues were beginning to arise, such as pharmaceuticals that may pass through normal treatment processes etc. Look forward to your presentations on anaerobic and aerobic sludge digestion and solids dewatering and wastewater disinfection. Plenty of other related topics such as wetlands also.
Not an engineer, but these videos are a great help in understanding the complexities of our urban infrastructure. This one's a twofer for me, because I grew up on a farm and hard cider was a basic commodity, keeping farmers hydrated and just happy enough to keep working despite how hard it was.
As a fellow home brewer, I loved this video. Question for you. I live decently close to a water treatment facility and it casts an awful stench that wafts hundreds of yards away from the source. Is there a way to reduce this undesirable side effect of water treatment?
You should report the odor to your local water/wastewater utility. They may need to come check it out and to make sure the vents and filters are working properly.
What a previous comment said, report it. It's the spring/summer swing right now, lots of increased biological activity and things flow/react differently due to a higher temperature. If it's stinky sulpher eggs they need to clean out their clarifier, that's usually the common source. For your own personal environment, planting trees or bushes makes a pretty good smelling windbreak.
Fascinating topic! I can relate to your wish to create an analogy between wastewater treatment and something as well-known such as beer making. I've been both a homebrewer and and an aquarist, and there's a system called a refugium used with aquariums to remove nutrients that become harmful to fish in high concentrations. There are a number of microorganisms used to used to convert ammonia to nitrates (bio-filtering), and then plants are grown in a separate sump to consume those nitrates and remove them.
Since microbes are so important in sewage treatment, how does everyday disinfectant such as PCMX and benzalkoniumchloride affect the treatment process? Do these make the treatment any harder?
benzalkoniumchloride is a big word. you must me really smart. im just messing with ya. some evaporate before they ever reach treatment and others are just not at any concentration to be effective at all. I always wondered about all the chemicals that go down the drain.
@@Wtfinc yeah, for every person bring irresponsible and pouring chemicals down the drain, there are 99 other people pouring regular water down the drain, to dilute the chemicals. I hope those microbes are safe
One thing you have to realize is that everything is powerfully diluted by massive amounts of water and sewage products. Not to mention what those twenty dollar word chemicals decompose into.
Absolutely. Waste treatment plants monitor the influent streams for chemicals that can harm "the bugs" as they call them. Residential producers rarely cause a problem since it's so diluted but commercial facilities are a different story. Often these companies work closely with waste treatment orgs to ensure their effluent is up to spec. Often this involves pH adjustment. If it falls out of spec, they will notify the plant, and sometimes they can react to prevent colony collapse. Accidents can and do happen. Heard about a chem lab where an idiot poured a liter of dichloromethane down the drain. It killed the whole colony in the plant's digester. They were fined tens of thousands of dollars.
In a municipal treatment system there's usually enough water to dilute chemicals to a safe (for microbes) level. But a home with a private septic system doesn't generate that much wastewater, so the occupants have to be careful about what goes down the drain. You'll see some cleaning products labeled as "safe for septic systems" for that reason.
Hey I enjoyed this messy journey on learning about waste treatment. I would love if you can cover natural water treatment systems. Like constructed wetlands ect.
I have consistently reflected on just how great this channel is; e.g. "the world should see this". This time, I'll borrow a reference: I was thoroughly "engrossed" LOL Thanks, Grady for all you do
Its one of the 2 big issues with farm runoff (the other being pesticides). The basic concept is you cause an algea bloom and then at night it isn't photosynthesizing amd gow from net oxygen producer to net consumer and suddenly everything in the river suffocates. For farms one solution is to leave a buffer of land plants like grasses and shrubs untamed so the land plants consume all the excess nutrients in the water before it reaches the river.
Waste water Engineering is obviously very interesting branch of Engineering yet very cumbersome to explain to enthusiast... You made it absolutely easy.. thank you🙏
I may never touch a beer again lol Grady you never fail to impress with your creative spins on getting engineering concepts into the everyday minds. And by the way.....YES!! The return of the post video cooking segment!
Super excited to see another home brewer. I think that was a great parallel between brewing yeast and sewage clearing microbes. One of my favorite youtubers. Keep up the good work!
I went from a cogeneration ethanol-biogas plant (attached to a cow feedlot) into wastewater and love the similarities. The smells are less fun but the variabilities caused by intrusive flows are more exciting and less your fault than flat out fowling a yeast propagation!
I know you briefly mentioned it in this video, but it may be worth taking a deep dive into how the ISS reuses waste, and how that differs (if at all), given that there is no gravity.
I have been making home brew spirits and wines for a few years, really good watching your video. You have your facts straight and it makes it so much more enjoyable. Keep up the great work. Interesting how many similarities there are!
I do water management using enzymes, so fermentation to clean up organics, reduce nitrate and pathogens is my living. One correction so algae produces oxygen during the day, however consumes it at night, the consumption often exceeds the existing Dissolved oxygen, hence it dies off.
I think one of the coolest advancements in the wastewater treatment field has been the ability to store methane gases created by the sludge digestion systems to use as a fuel to power the electricity to operate the facility. Not only have we created reuse water but reuse gases to power the treatment process. It’s an entirely self sufficient system.
Methane fuel cells are pretty well suited for this application. My small city tried to use a gas turbine but it never worked right and just the ongoing repairs cost more than the electricity it saved.
I visited a sewage plant in the uk back in the 70's and they were collecting methane to drive a gas turbine for electricity back then. It wasn't enough to be self sufficient, but helped a lot.
When I was doing my chemistry PhD, I looked a lot into the limitations for what we were allowed to dispose of down the drain. Some of the results were quite surprising, as they were mediated more by the effect the pollutants would have on the sewer microbes rather than humans! Lead? - no big deal. Nickel? - keep that antimicrobial stuff out!
@@edojayakusuma8209 the sewage system was capable of filtering out the lead, so it was removed before the treated water was released. the nickel would be removed too, of course, but not before it caused greater disruption to the microbes that break down organic nutrients.
I have some workforce experience on the compressor units that flow air into the tanks, both to grow yeast and treat water - as well as suck out excess methane from water treatment plants, the work i do and the places i do it at are absolutely fascinating
Looking at the comments you've certainly attracted the attention and support of a lot of wastewater treatment operators! Thanks for the video Grady! BTW,what do you call the hand & arm motions that you were demonstrating at 11:25? I'd never imagined that you might possess such impressive moves !!!
Would be good to do a video on advance water treatment plants and the problems of microplastics and PFAS, especially from industrial wastewater streams
@@alexandermarvin9536 yes there are BODAC has shown a lot of promise as your don't need to regenerate your activated carbon. We already have plants that use wastewater effluent and BODAC filters to make ultra pure water so we are working on it. There are also many forms of advanced oxidation which can do wonders.
Some municipalities use man made wetlands/cat tail farms to remove nutrients and particulates. Columbia Missouri is a great example of this. All the water ends up in a wild life conservation area called Eagle Bluffs. But from an ecologist's point of view, the nutrient load isn't the only pollutant: hormones and pharmaceuticals are also major contaminants that are especially hard to remove. There are sites where waste water is dumped into streams that the hormones from birth control and such have mutated aquatic animals into all females. Fish eggs and bi-valves are sensitive to environmental chemicals and the hormone levels in 'clean' effluent can be absorbed changing the physical sex (this leads to infertile animals though - harming the local population).
@@vasiliy5548 well... to get pedantic, it would be trans... but animal morphology/sex can be strange. There are certain fish that can change sex after they reach maturity and actually produce fertile offspring: Cichlids being the most known example. Its called sequential hermaphroditism. There are a few contested examples of this happening in frogs... but it is often associated with polluted waters in the egg/tadpole stage. In the reptile/amphibian world, sex is often determined not by genetics but temperature during incubation. Hormones still pay a role though and can obviously shift things during development. Despite some fish doing this naturally, it is only a few genera that have been observed doing this naturally. Many cannot. Bi-valves, being filter feeders, are also greatly impacted. And since they can't easily move, having a local population of 1 sex can reduce its ability to reproduce.
The plant I used to work at before retiring had it's own water treatment system. Various infrastructure took solids and oils out, etc. But the key thing the city was most worried about was the Ph level leaving the plant. Too much on either side it could play havoc with the microbes in the city sewage treatment plant. Since we used a lot of caustics to wash parts before welding, there was usually a slow sulfuric acid drip going into the waste water to balance the Ph, protecting the microbes downstream.
enGROSSing, nice one. while we're here, i love your videos, been watching the guys for the last few years by now and understanding an engineer's point of view is absolutely terrific
Ideally there isn’t a noticeable smell. The raw sewage coming in has a smell to it, but once it gets to the aeration basin the smell goes away. You’ll only get a bad smell when there is a lack of oxygen supplied to the microorganisms and they start dying, or when the solids get to the digesters which he will likely be covering in the next/future video.
I'm doing drawings for a wastewater treatment plant and its motivating to learn more about the parts I've been looking at. When I saw the title, I thought you might mention "Mixed Liquor" :)
I wonder if incorporating and allowing algae to bloom by using the nutrients in a controlled environment would be a good way to capture carbon and create biofuels from our waste.
In Switzerland it is forbidden to use the purified waste water (e.g. for watering plants etc.). This is because the water still contains many undesirable substances such as hormones. These hormones would then be in the food. It must first be led into a river or lake where it is further purified or further diluted.
Yet another point of overlap: the concentration of different ions in the municipal water supply changes how commercial breweries (and homebrewing, for nerds) do their thing. You can even mimic historical beer styles (e.g., out of Vienna) by matching municipal water profiles from hundreds of years ago.
Years ago (early 70's) our small town got an upgrade. Before, we had just primary treatment and built a 'state-of-the-art' activated sludge plant. For tertiary treatment, a rotating micro filter that helped catch sludge particles.
I thought I would see a lot of strange things in my life, but to censor the russian flag on the ISS is ridiculous. What motivated you to do that? Great video otherwise though.
Great video, Grady! I know your channel is more about engineering than chemistry, but a brief history of fermentation and some of the systems that were engineered to achieve fermentation through the centuries would be a great follow-on to this bit. Other ideas: * While you're on the subject of advanced biological wastewater treatment, you might consider nitrification and denitrification, as well as more advanced treatment processes like shunt denitrification. * For biosolids treatment, I can think of all kinds of episodes you could do on aerobic and anaerobic digestion. The engineering behind the egg-shaped digesters at 8:40 in this video would be a fun exploration. Also, consider composting methods (e.g., static pile, aerated pile, windrows, etc.), sludge drying, sludge incineration, and a discussion about practical uses for both Class B and Class A treated biosolids. Just some things to consider for future content. Signed, An avid fan of this channel! PS - In your video, you mention that Wichita Falls is an example of "toilet to tap," which I think was true between 2013 and 2015. Since then, I think Wichita Falls has ended its Direct Potable Reuse program and has converted it to an Indirect Potable Reuse system. Not quite toilet to tap since the treated wastewater makes a pit stop in Lake Arrowhead, but it's still pretty close.
I'm working for a company that specialises in brine treatment and it is really amazing how far the reuse of water and substances has come in the last years. It is now possible to get a brine stream up to 200.000 mg/l of salt and treat it to potable water and a solid salt product
I did a project for college on using flotation for wine making. And the only usefull source I could find that was even a bit similar was for waste water treatment. Something that at the time I worked 2-3 weeks around in the hope of finding a better source. By now I have learned better.
🥑 Use code PRACTICAL16 and try HelloFresh today at bit.ly/30Tr2CE
📖 Preorder your copy of my new book, Engineering in Plain Sight: An Illustrated Field Guide to the Constructed Environment at practical.engineering/book
Thoghts on methane collection and use the fertilizers more yes were talking about the same number 2.
If you drink beer try to get a few cans of Windhoek Lager, which is a beer that is actually brewed from recycled sewage water, at the brewery in Windhoek Namibia. The town recycles sewage water into drinking water, mostly because it is situated in a large desert near the ocean, and desalination, and bringing in water, is expensive, so recycle it is. The one thing it does have in abundance is sunshine, so it is easy enough to at least use solar power to heat your household water, though the region is not called the Skeleton Coast for nothing, and it is the corrosion capital of the world, with salt spray and fine sand, actively working to remove protective coatings off metal.
Both gross
That is an awesome little stool you got for your kid.
its crazy that waste water treatment originally began as brewing ale, beer, wine, and so on as a clean, and comparatively safer alternative to what was back then a very unpleasant "fresh water" source, drinking booze way back actually prevented you from suffering all kinds of diseases from e.coli to malaria to parasites to bacterial infections, and while today liquor is mostly seen as just a vice or past time, it really was essential for survival in ancient times. especially since ale and mead was more nutritious than most food of the time available to commoners.
I spent a couple of decades as a wastewater treatment plant professional. Retired now and one of my hobbies is home brewing. All that time in the lab must have been somewhat enjoyable for me to consider brewing an option for a hobby.
Thanks for treating our waste!
I worked in a big aquarium fish importer and we used a lot of the same systems. On a way smaller scale of course.
@@jiveturkey9993 Some of those fish farms in Asia have actually insane water treatment systems for the fish because they literally pack them in the farms like how we used to chickens in the US. The water has to be constantly cleaned and aerated to make sure the fish and bacteria are able to breathe, clean up waste, prevent Ammonia buildup.
What did you studied and where were you employed? Sounds funny but I’ve been interested in water plants for a while, it also seems like steady work
@@ramses6163 Any entry college biology courses, or appropriate trade schools are good places to start. Many countries have dedicated water treatment operations courses that can be started online. Check out your local government or college websites for possible information. Also many employers have on the job training for the promotion of in house employees who want to improve their skills. Good luck!
I love how you can combine a liquid that's the combination of people's waste and a liquid that makes people wasted in one video and make anyone feel interested in it.
Brew juice to cider, convert cider to pee, treat pee into reclaimed water, use reclaimed water to irrigate orchard. It's the ci-i-ircle of life
@@PKMartin And just to get even more circle of life, the yeasts consume sugar from the apple juice and pee out alcohol, so we're consuming another organism's waste for our fun and delectation.
I see what you did there
Grady, you were basically smiling this entire episode. Your ability to transmit educational material to the youtube masses with such enthusiasm is so energizing and contagious. You can really tell you enjoy learning just as much as you enjoy teaching.
Also congratulations on your new one!!!
Well said well said
@@davidwallace1644 It's easier to smile when you have plenty of hard cider...
I noticed this too. I suppose a smile is contagious and in this case it most definitely is.
Effects of the cider
Came here to say that haha ^^
I currently work for a municipal water utility in the wastewater department. When I first started working here, they took us all on a field trip to one of the treatment plants. The plant manager bragged on the plant and said, because of the organisms, he felt more like a zookeeper than a sewage treatment plant worker. “Gotta keep ‘em happy!”
I love that in every video, there are techs and engineers who work and specialize in the topic in question. Thanks for doing your part to keep the modern world safe and running smoothly.
A few things to note to the more curious:
1. While we do pump a lot of Oxygen (or just air that has 21% Oxygen, since it's free :P) into the tanks, not all steps/tanks are aerated. Most notably the Anaerobic (for removing Phoshorous) and Anoxic (for removing Nitrogen) tanks are mixed without aeration.
2. BOD is still used today, though nowadays COD (Chemical Oxygen Demand) seems to be more preffered afaik. Though personally I still use BOD most of the time.
3. Nowadays, systems like MBBR/IFFAS are becoming more popular as they require less space and air, and are more efficient. The TL;DR is that in the tanks with aeration we drop tons of small plastic chips on which the microbial colonies later grow, which in turn increases the dencity and speed of the biological proccesses. This/ along some other things make the system more complex. :P
4. One of the big problems that remain, is how to deal with the excess sludge/biomass that is produced on a daily basis? Sure, we prevented it from reaching the downstream water, which is good, but what to do with it now? This is a big topic in itself, and one that is still developing right now.
About point #3, how difficult is it to remove the plastic chips added/what happens to them?
Also adding plastic "confetti" for microbes to grow on is one of the problems caused by microplastics in the ocean, do you know if the treatment method is inspired by this problem or if someone from the treatment industry had an "oh shit" moment about the plastic in the ocean?
Is it viable biomass for fuel?
The lab/plant I work at runs BOD and COD. I don't personally because I'm not a chemist (yet), but yeah, we do both... is that unusual?
at the treatment plant where I used to work we dried the biosolids and turned them into fertilizer
@@randomfastreader The waste treatment department in the city where I used to live sold the dried solids as fertilizer too, although they cautioned people to not use it on anything that was going to be eaten. Their biggest concern was toxic metals.
For a while a common prank in the city was to buy some of the fertilizer ($5 for 100 pounds) and spread it on someone's lawn to spell out rude words.
As a professional brewer, you did a great job explaining the basics in an easily "digestible" way. Cheers!
I'm sad you didn't say "sessionable" 😔 lol.
Even before watching the video, and being in wastewater I glad you are covering this! Duality of life, one man’s trash is another organism treasure (aka food) and vice versa. The many wonders of life and how every life form is engineered to balance each other.
Great video! On a side note a lot of my former coworkers in the industrial wastewater are great at brewers. Some even culture their own yeast.
Omg, you shouldn't be *in* wastewater!
Get out before you catch a disease!!!
Well, both have the same function, make water transform into a drinkable liquid, by using a bacterium or yeast to outcompete the bad bacteria or yeast, so that they die out, leaving only the desired microorganisms around in the massive number, that ensures there is only a monoculture there, cleaning the water and making it safe to drink.
А Переработка стоков в Биогаз
Life wasn't engineered tho
@@Ebani Life was engineered by the balancing forces and harsh conditions of billions of years of evolution... What do you mean?
A nice "Addendum" to the sewage series would be how it's treated on the ISS, since most of ground-based treatment involves gravity which the ISS can't really take advantage of.
It gets compacted down and essentially freeze dried. Then it gets thrown overboard and burns up in the atmosphere.
@@DrewNorthup You described how the solids are disposed of, but I took the question to refer to the process of separating the water and solids, in the absence of gravity.
Is it centrifuges? I really hope it's centrifuges :D
@@RyanTosh it's centrifuge.
@@kornaros96 yay :D
Grady, I work for a construction company that specializes in water and wastewater treatment, and i must say, i thoroughly enjoy all your videos on the topic. Please feel free to reach out anytime if you feel you ever needed additional information for these videos! Keep up the good work!
Love the series about waste water Grady, keep it going!
Show him what you got Grady.
This was a really interesting video for me, because not only do I like an occasional beer or especially cider, but I work in a plant that uses recycled water! We make brown paper (linerboard or containerboard) from recycled corrugated boxes (aka OCC). The process uses a ton of water to break down, refine and store the paper pulp. You can't pump it if it's more than 5% paper, so that means every tank has at least 95% water in it. And it's all sort of dirty water with fine particles and dissolved solids. But we also bring in 100s of 1000s of gallons per day, as well as discharging to the city after treating and going through our own clarifiers. We also monitor temperature, pH, and flow (instant and total). We're allowed to take a certain amount from the river on our property, but the remainder of our water use is supplied from the city waste treatment plant. Effluent quality water is piped up to us (about 3 miles) and we use up to 1000gpm at times. The pipes, the tank, and the pumps are purple. There are also some purple fire hydrants that I don't recommend playing in when they get flushed out. Thanks so much for this video, really enjoyed it. --RB in CT.
When the news gets me feeling down, there's nothing quite like a glimpse of human ingenuity to help me feel optimistic again. Thanks, Grady and all innovators working to make the world a better place.
4:46 I love how satisfied Grady looks after dropping that rhyme XD
Before I became a operator I was interning at a brewing company for my degree and never once did I think I would correlate to my current career as a wastewater man. Great vid!
Good stuff, as always. I wanted to pitch an idea for a future topic: landfills. Would love to learn more about the engineering and science behind construction, site selection and functionality.
The output of both tastes wonderful (:
Hol up what
😯😯
Lolll had me for a second 😂 I guess you could say that.
Just because you aren't wrong didn't mean this comment was ok 😂
Yikes
Been years since I've interned with the MWRA and I've never seen that view of it before but that initial 5 second shot looks like the digester eggs at Deer Island Waste treatment facility in Boston (should be Logan right there in the shot too). It was a pretty cool experience seeing how all that worked and I also learned that part of the sewage in that whole system gets turned into fertilizer
I used to work next to an active demonstration sewage treatment system and after that experience I would say that your neighbors thank you for not replicating it in your garage. This was a museum where the entire second floor's wastewater was treated in one of the exhibits (but then secretly sent on to the sanitary sewer). On warm summer nights the smell was quite strong, even for such a small system. We also had the largest roaches that most people have ever seen!
I love learning from you. You're thorough and enthusiastic, as well as kind in your explanations, and though you never dumb down, you always manage to explain everything in terms we can all understand. Your enthusiasm is so contagious, too - I enjoy learning about the world around us in all sorts of ways, and your videos are definitely top of the list for infrastructure and engineering. Thanks so much for taking the time and effort to make such enjoyable and engaging content!
100% agree with you... a wonderfully informative and entertaining channel... "the world should see these"
I almost always skip thru the commercials and sponsor's message on YT videos but your family keeps me watching. That handsome little guy is an excellent helper. Your whole meal prep situation is almost identical to mine. Keeping those toddlers busy is THE challenge, yeah?!
Congrats on the next child and the excellent hobby of home brewing :) living the life Grady.
Man. You are everything that is good about UA-cam. So many useless channels, but you always teach me something new and interesting
This was a fun video to watch!
I'm a starting homebrewer myself, focussing on beer. This is the first time I've heard that yeast would stop producing alcohol when exposed to oxygen. Anaerobic processes is a new thing I've leared today. Thank you!
AFAIK, you should only leave a bit of air at the top of the container when fermenting most alcohols. In fact, I was worried about too much air in his fermenter.
Mind you, I'm a novice at this, still. Don't take my word as law.
I have a degree in food science with an emphasis in brewing. You absolutely NEED O2 to get your yeast going. Without going into complexities, yeast are not strictly anaerobic. If you didn't have any O2, then fermentation wouldn't probably be as vigorous as you'd want and/or wouldnt begin much at all.
@@kirkgoingham6095 But you have to oxygenate the mix at the beginning (by shaking) and then let it be in the container with as little air as possible, right?
After the initial step, I always heard that you have to try to introduce as minimum air as possible. Please correct me if I'm doing it wrong.
Exactly! 99% of the time in home brewing transferring your wort to your primary fermentation is enough exposure to air for your brew to turn out great. Or, if you wanna be extra careful just leave the airlock off for a little longer. Everyone has their own rituals lol.
And, yeah, try your best not to reintroduce air because that will slow down the metabolic pathway yeast use to facilitate alcohol production, but nothing's perfect in homebrewing, especially when you transfer into a secondary. You're gonna get air, but as long as you plug that sucker up, you'll be fine!
@@kirkgoingham6095 yeah before the yeast is pitched we usually shake the vessel and aerate with a whirlpool paddle to get some 'starting oxgyen' for the yeast to grow.
This side by side demo is great. Grady, you're great. Love your explanations over the videos of what you're talking about.
Would love to see a biosolids removal process video next! We typically land apply our sludge, but haven't needed to in years. It would be neat to see land application vs. drying, and other removal options compared in a video. Good stuff as always!
A good overall review for the general public on wastewater treatment. Obviously there are many other issues that must be addressed in design of facilities but that is what trained engineers are for. In my 38 years of consulting practice I designed countless waste treatment facilities (mainly activated sludge but some trickling filers) for both municipalities and industries. Everyone was a learning experience and over my time we went from mainly secondary treatment reducing solids (TSS) and BOD to first converting organic nitrogen to nitrates in the nitrification process to removing almost all nitrogen and phosphorus by additional techniques also. Sometimes the regulatory agencies required such low effluent concentrations of these parameters we had develop tertiary treatment steps or enhance the secondary processes to increase removal rates. Industrial wastes could be especially troublesome due to presence of toxins but these could be successfully treated individually prior to discharge to the downstream treatment facilities. At the time of my retirement new issues were beginning to arise, such as pharmaceuticals that may pass through normal treatment processes etc. Look forward to your presentations on anaerobic and aerobic sludge digestion and solids dewatering and wastewater disinfection. Plenty of other related topics such as wetlands also.
Thank you a LOT for these videos, Grady! It's very relaxing to learn about all the systems that make life more safe and comfortable.
Not an engineer, but these videos are a great help in understanding the complexities of our urban infrastructure. This one's a twofer for me, because I grew up on a farm and hard cider was a basic commodity, keeping farmers hydrated and just happy enough to keep working despite how hard it was.
Congratulations on the growing family!
Watching your videos gave me a clear understanding of how wastewater treatment works. It made passing my grade V wastewater exam seem easy. Thank you
As a fellow home brewer, I loved this video. Question for you. I live decently close to a water treatment facility and it casts an awful stench that wafts hundreds of yards away from the source. Is there a way to reduce this undesirable side effect of water treatment?
Short of putting enclosures over the tanks and adding ozone to the escaping air, probably not much. They don't call 'em "sh*t factories" for nothing.
Pinching the nostrils and mouth breathing reduces the odors found adjacent to waste water treatment facilities.
@@texhunter1820 bruh I've tried this already and I taste it instead
You should report the odor to your local water/wastewater utility. They may need to come check it out and to make sure the vents and filters are working properly.
What a previous comment said, report it.
It's the spring/summer swing right now, lots of increased biological activity and things flow/react differently due to a higher temperature. If it's stinky sulpher eggs they need to clean out their clarifier, that's usually the common source. For your own personal environment, planting trees or bushes makes a pretty good smelling windbreak.
Fascinating topic! I can relate to your wish to create an analogy between wastewater treatment and something as well-known such as beer making.
I've been both a homebrewer and and an aquarist, and there's a system called a refugium used with aquariums to remove nutrients that become harmful to fish in high concentrations. There are a number of microorganisms used to used to convert ammonia to nitrates (bio-filtering), and then plants are grown in a separate sump to consume those nitrates and remove them.
Since microbes are so important in sewage treatment, how does everyday disinfectant such as PCMX and benzalkoniumchloride affect the treatment process? Do these make the treatment any harder?
benzalkoniumchloride is a big word. you must me really smart. im just messing with ya. some evaporate before they ever reach treatment and others are just not at any concentration to be effective at all. I always wondered about all the chemicals that go down the drain.
@@Wtfinc yeah, for every person bring irresponsible and pouring chemicals down the drain, there are 99 other people pouring regular water down the drain, to dilute the chemicals. I hope those microbes are safe
One thing you have to realize is that everything is powerfully diluted by massive amounts of water and sewage products. Not to mention what those twenty dollar word chemicals decompose into.
Absolutely. Waste treatment plants monitor the influent streams for chemicals that can harm "the bugs" as they call them. Residential producers rarely cause a problem since it's so diluted but commercial facilities are a different story. Often these companies work closely with waste treatment orgs to ensure their effluent is up to spec. Often this involves pH adjustment. If it falls out of spec, they will notify the plant, and sometimes they can react to prevent colony collapse.
Accidents can and do happen. Heard about a chem lab where an idiot poured a liter of dichloromethane down the drain. It killed the whole colony in the plant's digester. They were fined tens of thousands of dollars.
In a municipal treatment system there's usually enough water to dilute chemicals to a safe (for microbes) level. But a home with a private septic system doesn't generate that much wastewater, so the occupants have to be careful about what goes down the drain. You'll see some cleaning products labeled as "safe for septic systems" for that reason.
I work as sales engineer in Wastewater and it is very exciting to see you cover any of these topics!
This year i just joined a water treatment plant project, your content is very helpful 👍 thank you so much!
Kudos for this channel from Indonesia!
"If it's clear and yellow, you've got juice there, fellow! If it's cloudy and brown, you're in cider town!"
- Ned Flanders
You got me at "fermenting beverages."
Thanks, Grady. All of my fermenters, and
my kegerator thank you.
steve
Hey I enjoyed this messy journey on learning about waste treatment. I would love if you can cover natural water treatment systems. Like constructed wetlands ect.
I have consistently reflected on just how great this channel is; e.g. "the world should see this". This time, I'll borrow a reference: I was thoroughly "engrossed" LOL Thanks, Grady for all you do
I didn't even know you could pollute a river with nutrients. This was awesome to learn!
Its one of the 2 big issues with farm runoff (the other being pesticides).
The basic concept is you cause an algea bloom and then at night it isn't photosynthesizing amd gow from net oxygen producer to net consumer and suddenly everything in the river suffocates.
For farms one solution is to leave a buffer of land plants like grasses and shrubs untamed so the land plants consume all the excess nutrients in the water before it reaches the river.
If you want to learn more, the keyword to search for is "eutrophication".
Waste water Engineering is obviously very interesting branch of Engineering yet very cumbersome to explain to enthusiast... You made it absolutely easy.. thank you🙏
I may never touch a beer again lol Grady you never fail to impress with your creative spins on getting engineering concepts into the everyday minds. And by the way.....YES!! The return of the post video cooking segment!
Super excited to see another home brewer. I think that was a great parallel between brewing yeast and sewage clearing microbes. One of my favorite youtubers. Keep up the good work!
I went from a cogeneration ethanol-biogas plant (attached to a cow feedlot) into wastewater and love the similarities. The smells are less fun but the variabilities caused by intrusive flows are more exciting and less your fault than flat out fowling a yeast propagation!
Thanks!
I know you briefly mentioned it in this video, but it may be worth taking a deep dive into how the ISS reuses waste, and how that differs (if at all), given that there is no gravity.
This should be higher
I have been making home brew spirits and wines for a few years, really good watching your video. You have your facts straight and it makes it so much more enjoyable. Keep up the great work. Interesting how many similarities there are!
I do water management using enzymes, so fermentation to clean up organics, reduce nitrate and pathogens is my living. One correction so algae produces oxygen during the day, however consumes it at night, the consumption often exceeds the existing Dissolved oxygen, hence it dies off.
The intro has me laughing into tears. Thank you for all of the wastewater treatment videos lately. Wastewater is my passion!
I think one of the coolest advancements in the wastewater treatment field has been the ability to store methane gases created by the sludge digestion systems to use as a fuel to power the electricity to operate the facility. Not only have we created reuse water but reuse gases to power the treatment process. It’s an entirely self sufficient system.
Methane fuel cells are pretty well suited for this application.
My small city tried to use a gas turbine but it never worked right and just the ongoing repairs cost more than the electricity it saved.
I visited a sewage plant in the uk back in the 70's and they were collecting methane to drive a gas turbine for electricity back then. It wasn't enough to be self sufficient, but helped a lot.
Just wanted to let you know that I'm thankful for your videos.
When I was doing my chemistry PhD, I looked a lot into the limitations for what we were allowed to dispose of down the drain. Some of the results were quite surprising, as they were mediated more by the effect the pollutants would have on the sewer microbes rather than humans! Lead? - no big deal. Nickel? - keep that antimicrobial stuff out!
That's very interesting, thanks for sharing!
But doesn't disposing the water with lead can cause water contamination to ground water? Or people just don't care?
@@edojayakusuma8209 the sewage system was capable of filtering out the lead, so it was removed before the treated water was released. the nickel would be removed too, of course, but not before it caused greater disruption to the microbes that break down organic nutrients.
I have some workforce experience on the compressor units that flow air into the tanks, both to grow yeast and treat water - as well as suck out excess methane from water treatment plants, the work i do and the places i do it at are absolutely fascinating
Yep, sewage and human waste is a fascinating subject.
*Continues eating lunch without batting an eyelid*
Looking at the comments you've certainly attracted the attention and support of a lot of wastewater treatment operators! Thanks for the video Grady! BTW,what do you call the hand & arm motions that you were demonstrating at 11:25? I'd never imagined that you might possess such impressive moves !!!
Would be good to do a video on advance water treatment plants and the problems of microplastics and PFAS, especially from industrial wastewater streams
I've heard there are processes being developed to remove microplastics from normal wastewater streams.
@@alexandermarvin9536 yes there are BODAC has shown a lot of promise as your don't need to regenerate your activated carbon. We already have plants that use wastewater effluent and BODAC filters to make ultra pure water so we are working on it.
There are also many forms of advanced oxidation which can do wonders.
I don't know if you're a regular home brewer, but you nailed it. Well done.
Some municipalities use man made wetlands/cat tail farms to remove nutrients and particulates. Columbia Missouri is a great example of this. All the water ends up in a wild life conservation area called Eagle Bluffs. But from an ecologist's point of view, the nutrient load isn't the only pollutant: hormones and pharmaceuticals are also major contaminants that are especially hard to remove. There are sites where waste water is dumped into streams that the hormones from birth control and such have mutated aquatic animals into all females. Fish eggs and bi-valves are sensitive to environmental chemicals and the hormone levels in 'clean' effluent can be absorbed changing the physical sex (this leads to infertile animals though - harming the local population).
Oh, that's where "they're turning frogs gay" comes from
@@vasiliy5548 well... to get pedantic, it would be trans... but animal morphology/sex can be strange. There are certain fish that can change sex after they reach maturity and actually produce fertile offspring: Cichlids being the most known example. Its called sequential hermaphroditism. There are a few contested examples of this happening in frogs... but it is often associated with polluted waters in the egg/tadpole stage.
In the reptile/amphibian world, sex is often determined not by genetics but temperature during incubation. Hormones still pay a role though and can obviously shift things during development.
Despite some fish doing this naturally, it is only a few genera that have been observed doing this naturally. Many cannot.
Bi-valves, being filter feeders, are also greatly impacted. And since they can't easily move, having a local population of 1 sex can reduce its ability to reproduce.
I genuinely enjoy this channel and all its content, thank you for sharing your knowledge so eloquently! Big fan from Rocket City, HSV AL
i always knew Heineken had alot in common with sewage
May this channel live forever.... This and RealEnginnering are my favorite...
Do you sweeten your cider, or drink it dry? What are your thoughts on on adding back in apple flavor, either from concentrate or flavoring products?
Stop the ferment where you want it. Backsweetening is the devil. Disagree all you want, it's okay to be wrong.
@@nobodynoone2500 I have to agree. You might as well go buy some disgusting Strongbow
The transition between actual video and ad was smoothhh!!!
The plant I used to work at before retiring had it's own water treatment system. Various infrastructure took solids and oils out, etc. But the key thing the city was most worried about was the Ph level leaving the plant. Too much on either side it could play havoc with the microbes in the city sewage treatment plant. Since we used a lot of caustics to wash parts before welding, there was usually a slow sulfuric acid drip going into the waste water to balance the Ph, protecting the microbes downstream.
enGROSSing, nice one. while we're here, i love your videos, been watching the guys for the last few years by now and understanding an engineer's point of view is absolutely terrific
They say he's called Grady because he likes grades, grading, gradients, and all things grade related
Of all videos that equate beer and sewage, this one is the best!
Out of curiosity, how does the smell change as it goes through the various stages?
Ideally there isn’t a noticeable smell. The raw sewage coming in has a smell to it, but once it gets to the aeration basin the smell goes away. You’ll only get a bad smell when there is a lack of oxygen supplied to the microorganisms and they start dying, or when the solids get to the digesters which he will likely be covering in the next/future video.
Congratulations on the new sponsor.
Continued success my fellow Texan!
I'm doing drawings for a wastewater treatment plant and its motivating to learn more about the parts I've been looking at. When I saw the title, I thought you might mention "Mixed Liquor" :)
You’re one of my favorite channels! Thank you
I wonder if incorporating and allowing algae to bloom by using the nutrients in a controlled environment would be a good way to capture carbon and create biofuels from our waste.
We are already creating methane from out sludge, we fermentate the sludge in digesters which produces a lot of methane
Congrats on the new addition! Not into the spirits myself but great info and comparisons!
Hopefully it’s not that they both end up in my cup. I need to watch this before I finish my beer…
I love your inspiration, motivation, aura, knowledge, work and so many other things. Thank you very much for all the things you ve shown us.
In Switzerland it is forbidden to use the purified waste water (e.g. for watering plants etc.). This is because the water still contains many undesirable substances such as hormones. These hormones would then be in the food.
It must first be led into a river or lake where it is further purified or further diluted.
ah yes, let nature take the consequences instead of us humans.
noice
@@Dalziel45 Just in the first place. The water will leak into fields and throu citys again.
More gold content, Grady! Sharing with all my wastewater colleagues.
"What does Sewage Treatment and Brewing Have in Common?"
Rolling Rock does both.
I was going to say Heineken, but that works too.
You always make the best videos for me to watch during my lunch break.
Yet another point of overlap: the concentration of different ions in the municipal water supply changes how commercial breweries (and homebrewing, for nerds) do their thing. You can even mimic historical beer styles (e.g., out of Vienna) by matching municipal water profiles from hundreds of years ago.
Burton on Trent water copying seems popular
Years ago (early 70's) our small town got an upgrade. Before, we had just primary treatment and built a 'state-of-the-art' activated sludge plant. For tertiary treatment, a rotating micro filter that helped catch sludge particles.
I thought I would see a lot of strange things in my life, but to censor the russian flag on the ISS is ridiculous. What motivated you to do that?
Great video otherwise though.
Self-censorship and phobias, I guess
Congratulations on your impending new arrival! Thanks for the video. 😄
Imagine living in a "free country" and being told you can't grow certain plants, or ferment/distill alcoholic beverages
Or eat certain chemicals
Great video, Grady! I know your channel is more about engineering than chemistry, but a brief history of fermentation and some of the systems that were engineered to achieve fermentation through the centuries would be a great follow-on to this bit. Other ideas:
* While you're on the subject of advanced biological wastewater treatment, you might consider nitrification and denitrification, as well as more advanced treatment processes like shunt denitrification.
* For biosolids treatment, I can think of all kinds of episodes you could do on aerobic and anaerobic digestion. The engineering behind the egg-shaped digesters at 8:40 in this video would be a fun exploration. Also, consider composting methods (e.g., static pile, aerated pile, windrows, etc.), sludge drying, sludge incineration, and a discussion about practical uses for both Class B and Class A treated biosolids.
Just some things to consider for future content.
Signed,
An avid fan of this channel!
PS - In your video, you mention that Wichita Falls is an example of "toilet to tap," which I think was true between 2013 and 2015. Since then, I think Wichita Falls has ended its Direct Potable Reuse program and has converted it to an Indirect Potable Reuse system. Not quite toilet to tap since the treated wastewater makes a pit stop in Lake Arrowhead, but it's still pretty close.
Thanks for making this series! I'm currently in the interviewing process for a wastewater treatment operator apprenticeship
Nice to see a fellow brewer explaining the process! Brew on!
I'm facinated with the study of phage therapy and bacteriophage studies and research projects to see the potential knowledge we can gain from them...
I'm working for a company that specialises in brine treatment and it is really amazing how far the reuse of water and substances has come in the last years. It is now possible to get a brine stream up to 200.000 mg/l of salt and treat it to potable water and a solid salt product
Dude we have watched your previous videos.
AND WE LOVED THEM
You make some of the best content on the internet.
Thank you
would love to see a video on both biological and chemical waste management. keep up the good work Grady!
I feel like learned more in this video than I did in two courses on environmental engineering and wastewater treatment
I always smile when I see a notification that you have a new video out.
The family parts at the end with the sponsorship is quickly becoming my favorite part - lol. "dirty ice?" ha ha ha ha I can so relate.
this video basically sums up every tangent i’ve gone on during my chemical and biomolecular engineering degree!
My favorite segment is actualy you talking about engineering
I did a project for college on using flotation for wine making. And the only usefull source I could find that was even a bit similar was for waste water treatment. Something that at the time I worked 2-3 weeks around in the hope of finding a better source. By now I have learned better.
One of your best videos. Thank you Grady.