What is the main purpose of backwashing filters?

The main purpose of backwashing filters is to flush out contaminants that are trapped in the filter media. Over time, as water passes through the filter, particles, sediments, and other impurities accumulate in the media. This buildup can reduce the effectiveness of the filter and decrease the flow rate. Backwashing involves reversing the flow of water through the filter, which dislodges and removes these accumulated particles. This process not only cleans the filter, restoring its ability to capture additional contaminants, but also helps maintain the overall efficiency of the water treatment system.

While pressure and flow rate are affected during backwashing, the primary focus is on removing trapped materials to ensure the filter functions properly. Adding chemicals is not typically a part of the backwashing process; instead, chemical addition is usually a separate function within water treatment systems for purposes such as disinfection or coagulation.