Patent ID: 6514418
Filing Date: 2003-02-04
Classification: C02F

Abstract:
A process for dewatering a flocculated sewage sludge which has been flocculated with at least one organic flocculation aid, said process comprising the steps of:providing a plate filter, modifying the plate filter to permit an initial feed rate of at least 0.3 m3 sludge per m2 filter area per hour and a filtrate discharge flow rate of at most 1.0 m/second, introducing the flocculated sewage sludge into a plate filter, removing at least 50 wt.-% water from the flocculated sewage sludge in the plate filter by hydrostatic filtration to obtain partially dewatered sewage sludge, and thereafter subjecting the partially dewatered sewage sludge to pressure filtration in said plate filter.