Conveyance of Residuals from Water and Wastewater Treatment

Abstract

• Prepared by the Environmental and Water Resources Institute of ASCE.

  This Manual of Practice provides detailed guidance to determine the handling characteristics of residuals and to select appropriate conveyance systems. As residuals are processed and handled, their intrinsic properties (such as viscosity, rheology, flowability, and texture) change. If these changes are not recognized and the proper transport devices used, problems can result in the processing and disposal of these materials. To ensure correct handling and transport of residuals, this manual describes a procedure for classifying residuals according to their transport properties. A detailed examination of the rheology, composition, and transport characteristics of residual solids is included, as well as a comprehensive listing of the equipment available, with photographs and illustrations, for transporting residuals. By providing details on handling characteristics and transport equipment, this manual assists engineers in determining the most efficient type of transport for each of the major classifications of residuals: non-Newtonian slurries, thickened residuals, dewatered residuals, and granular and compactable residuals. Four case studies, highlighting lessons from actual operating installations, are also included. The specific equipment that produces the residuals to be conveyed is discussed to define any operating factors that could affect the transport characteristics.