Enzymatic treatment effects on aerobic sludge stabilization

Water/wastewater treatment processes have produced sludge in different characteristics and quantities. The sludges should be processed and disposed of in accordance with the environmental health criteria for environmental reasons. For many authorities and engineers, the effective sludge management is still a big challenge since the investment and operational costs of sludge processing have an important part of overall plant?s costs. Sludge dewatering process has a central role in sludge management for many operations like storage, transport. But, the dewaterability characteristics of sludges can vary depending on their sources and the applied processes. The methods for effective processing cover the methods -thickening, stabilization, conditioning, dewatering-, and the final disposal alternatives- incineration, land application.The main purpose of this thesis was to investigate the effects of hydrolytic enzyme additions on dewaterability performance of activated sludge during aerobic digestion process. Activated sludge was fed to the reactors as a feeding material. The parameters ? pH, electrical conductivity (EC), salinity, oxidation reduction potential (ORP), capillary suction time (CST), zeta potential, suspended solids content, dry solid content, organic matter- were analyzed to determine the sludge characteristics. Reactor performances with and without enzyme additions were monitored. Experimental results showed that the enzyme additions provided enhanced sludge disintegration. Enzyme added reactors showed considerably superior better performance in terms of organic matter reduction and EPS degradation when comparing the control reactor.This thesis as part of a project examining the effects of hydrolytic enzymes in biological sludge stabilization gives important research results to determine the floc disintegration mechanisms by enzymes during aerobic sludge digestion.