Biological Control in Cooling Towers

Michael Groh, talking about controlling the microbiome in cooling towers in the Seattle area, at a seminar put on in 2010 at the EMP by Seattle Public Utilities and the Saving Water Partnership.
4 areas of water treatment and guidelines for them: scale, corrosion, fouling, microbiology; 90% of cooling tower problems are a result of biological activity. Other topics covered include aerobic and anaerobic bacteria, algae, legionella, corrosion coupons, planktonic (free floating) and sessile (attached) (biofilm) bacteria, sessile is what causes the problems. Use dip slides to grow and measure bacteria and based on level of growth can determine how excessive the bacteria are. Types of biocides, oxidizing and non-oxidizing, need both, but non-oxidizing biocides works best on sessile bacteria.