BACKWASHABLE SAND FILTER
Sand filters are a common type of side stream filtration system.

Sand filters direct fluid into the top of their tank(s) and onto the surface of a bed of specified sand and/or other media. As the cooling water flows through the bed of sand media, suspended solids and other particles are captured within the upper layer of media. The water moves downward, passing into a drain at the bottom of the filter tank and discharging through an outlet pipe.

Sand filters are usually very efficient at removing the extremely fine and low density particles that cooling towers scrub from the air. Therefore, they generally have very high filtration rates. However, sand filters work less effectively with high density sand-like materials because these materials cannot be properly removed by backwashing.

• Return to the Cooling Water Filtration page.
  
• Return to the Pre-Filtration for Ion Exchange and Reverse Osmosis
  
• Information on Plastic Disk Filters
  
• Information on Automatic Screen Filters
  

The development of high efficiency sand filters has revolutionized cooling water filtration. Airborne contaminants can now be cost effectively removed with a backwashing filter.