Non-Chemical Alternatives for Cooling Tower Treatment

Michael Groh, talking about Non-Chemical treatment systems for 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.
Different types of non-chemical treatment systems for cooling tower water. WHY use non-chemical systems? - eliminate hazardous chemicals, better for environment, maybe better results, maybe less maintenance. Still need to meet standards discussed in biological control video. One type of system is the pulse systems including Dolphin/Pulse Pure/Griswold - they try to precipitate calcium carbonate out of solution and claim to damage cell walls or trap bacteria; evaluation of their performance shows good scale control, bad corrosion control, good bulk water bacteria control, poor control of bacteria on surfaces. Magnets/electromagnetic fields are another option. Water softener systems - which typically remove calcium and magnesium which helps reduce scale, and corrosion control by high cycles that have high alkalinity which prohibit corrosion. And with water softeners because you have to regenerate softeners you have some discharge. Water softeners have poor bacteria control. Ozone - works well on everything except scale and thus they are a bad choice.