Intermixing of Dual Media and Multimedia Granular Filters

The use of mixed‐media filters results in longer filter cycles and, in some cases, better filtrate quality than single‐media sand filters. Unfortunately, during backwashing the stratification of the sand particles in mixed‐media filters is rearranged. In this study two models for predicting the degree of intermixing between different media at proposed backwash rates and water temperatures were examined.