METHOD FOR DEHYDRATING SLUDGE IN SQUEEZE DEHYDRATOR

摘要

PURPOSE:To reduce the water content of dehydrated cake without unnecessarily increasing the amt. of a flocculant to be added and to improve the dehydrating property by providing a water washing stage prior to the flocculation stage in the method for dehydrating sludge by a squeeze dehydrator. CONSTITUTION:In the method for dehydrating sludge by a squeeze dehydrator such as a belt-press type dehydrator and a roller type dehydrator, a stage 102 for washing the sludge with water is incorporated between a stage 101 for supplying unflocculated sludge and a flocculation stage 103 for adding a flocculant to the stage. When sludge is thus washed with water, the dissolved components which exists in the liq. phase of the sludge prior to the flocculation stage and causes the clogging of a filter cloth, a filter, etc., and fine particles which coexists in the solid phase of the sludge and similarly causes the clogging are removed by the washing water. Accordingly, dehydration is effectively carried out.