New laboratory developments for sludge flocculation

摘要

The characterisation of sludge to assess in laboratory its amenability to thickening and dewatering is an operation highly sensitive to the operating procedure adopted for the chemical conditioning step. The defi nition of a standardized procedure is needed for the selection of type and dose of a conditioning product at laboratory scale. A new device was developed to ensure the repeatability of sludge fl occulation tests independently of the operator, and to prepare a homogenous thickened fl occulated sludge for subsequent dewatering tests. Results obtained with different kind of sludges, polymers and mixing conditions are presented in this paper.