Experimental and statistical models moisture release of the mixture treated with reagents raw sludge and compacted active sludge

Abstract

The technology of changing the resistivity of a mixture of raw sludge and compacted activated sludge taken after the sludge pumping station of urban sewage treatment plants by treating the sludge with aluminum sulfate and polyacrylamide (PAA) in doses from 0 to 300 mg/dm3 has been tested. The degree of influence of each reagent on the process of dehydration of the sediment under study has been established. It has been shown that PAA has about 2.0 times greater effect on the process of moisture loss than Al2(SO4)3 at reagent doses from 0 to 200 mg/dm3 and about 1.5 times – at doses from 100 to 300 mg/dm3. Mathematical models of the dependence of the change in the resistivity of the sediment on the amount of Al2(SO4)3 and PAA introduced into it are obtained. Mathematical models are also presented in graphical form (isolines). The optimal doses of coagulant and flocculant for chemical treatment of the studied sewage sludge were determined.