7 - Sludge Dewatering Operations

Abstract

The chapter provides an overview of alternative dewatering technologies used in wastewater treatment and sludge concentrating applications. Many of the techniques described in the chapter can be used in conjunction or integrated with filtration operations. The purpose of dewatering is to increase the solid content of the particulate matter separated out from filtration for one or more of the following reasons: dewatered solids are more easily handled; dewatering is normally required prior to incineration to reduce fuel requirements; dewatering reduces the cost of subsequent treatment processes, dewatering is required prior to land disposal of solids, and dewatering reduces the costs of transporting wastes recovered from filtration to their ultimate disposal by reducing their volume and weight. Dewatering technologies can be subdivided into two general processes: air-drying processes and mechanical processes. The chapter provides an overview of these technologies and concentrates on typical sludge dewatering operations used for wastewater treatment.