Title: Applications of Calcium Hypochlorite in Cooling Towers
This presentation will allow you to understand the uses and benefits of calcium hypochlorite in cooling towers.
Comparison of halogen sources
Cooling tower operators have a number of technologies available to them for controlling microorganisms in cooling towers. Cooling tower biocides are typically broken down into two groups: oxidizing and non-oxidizing. Oxidizing biocides including chlorine are a mainstay of cooling tower treatment due to their broad spectrum of activity and fast kill rates. There are a variety of oxidizing biocides available, so an operator can choose which disinfectant best fits their system and treatment program objectives. Each of these products has its advantages and disadvantages. Operators can choose whichever option has the properties they require, depending on their cooling water system, their storage facilities, and environmental discharge permits.
Calcium hypochlorite is a high concentration, low-cost, solid biocide option for treating cooling towers where liquid bleach presents various degradation, handling and other issues. For continuous treatment, the best applications are systems that are once-through or run low cycles of concentration, or where makeup water quality is of low-hardness and low-alkalinity. For routine or remedial cooling tower hyperchlorination disinfection, calcium hypochlorite presents several advantages over liquid bleach. It is shelf stable and can be stored on-site to be used on-demand, as needed. It is also much easier to transport, handle and apply compared to bleach.
There are a variety of oxidizing biocides available, including solid, liquid and gaseous chlorine sources, so an operator can choose which disinfectant best fits their system and treatment program objectives. In addition to comparing the different forms of chlorine and their stability, storage and handling, feed equipment and effects on corrosion and scale, this talk will also discuss application of calcium hypochlorite for continuous chlorination and hyperchlorination.
Ellen Meyer is Product Safety and Government Affairs Manager with Sigura, a leading global supplier of water treatment products. Prior to joining Sigura in 2001, Ellen worked at Betz Laboratories in Pennsylvania where she developed new products for industrial water and wastewater treatment. Ellen earned a B.S. degree in chemistry from The College of William and Mary and a Ph.D. in inorganic chemistry from Northwestern University. She is a former chair of the Recreational Water Quality Committee of PHTA. She currently serves on the chlorine stabilizer ad hoc committee for CDC’s Model Aquatic Health Code, the NSF-50 Joint Committee, and the AWWA disinfectants standards committee.