You are here:
CHEMICAL PRIMARY SLUDGE THICKENING AND DEWATERING
Citation:
Gregorio, D., J. Ainsworth, AND K. Mounteer. CHEMICAL PRIMARY SLUDGE THICKENING AND DEWATERING. U.S. Environmental Protection Agency, Washington, D.C., EPA/600/2-79/055.
Description:
This report presents the results of a ten month study of the thickening and dewatering characteristics of chemical-primary sludges. Alum-primary and ferric-primary sludges were produced in parallel trains of a pilot plant operated using a municipal wastewater. Each chemical treatment unit was operated under several coagulant doses during the four phases of this study resulting in the production of several chemical-primary sludges with distinct characteristics. Gravity thickening and dissolved air flotation thickening results for each chemical-primary sludge are presented. Gravity thickening was evaluated using continuous, pilot scale gravity thickeners; dissolved air flotation thickening evaluations were performed using batch, benchscale equipment. Sludge dewatering evaluations were performed for all chemical-primary sludges using a pilot scale bowl centrifuge, vacuum belt filter and filter press. The report presents correlations developed relating performance of each unit operation to specific characteristics identified for each chemical-primary sludge. An economic analysis of centrifugation and vacuum belt filtration of each chemical-primary sludge is presented.