Optimization of Flocculation in Connection with Various Solid-Liquid Separation Processes

Abstract

Coagulation and flocculation always involve solid-liquid separation processes. Numerous studies on coagulation and flocculation for water and wastewater treatment have postulated sedimentation and/or filtration as the typical accompanying separation processes. Therefore, much data is available on optimal coagulation and flocculation conditions defined on the basis of the above stream. Very often “good floe” was defined according to a conventional jar test procedure or similar procedures for optimal design and operation of treatment systems. In recent years, various new solid-liquid separation processes have been introduced into water and wastewater treatment streams. Direct sand filtration, coarse media filtration, multiple media filtration, microfiltration, ultrafiltration, fluidized pellet bed separation, etc. are relatively new or very recent technical innovations which broaden the range of possibilities for optimizing coagulation and flocculation. In the following discussion, the author intends to present a blueprint for selecting an effective solid-liquid separation process, and to propose optimal coagulation and flocculation conditions based on some of his own work.