Combination of alkaline solubilization with microwave digestion as a sludge disintegration method: effect on gas production and quantity and dewaterability of anaerobically digested sludge

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2008
Doğan, Ilgın
The significant increase in the sewage sludge production in treatment plants makes anaerobic digestion more important as a stabilization process. However hydrolysis is the rate-limiting step of anaerobic digestion because of the semirigid structure of the microbial cells. Pretreatment of waste activated sludge (WAS) leads to disruption of cell walls and release of extracellular and intracellular materials. Therefore biodegradability of sludge will be improved in terms of more biogas production and sludge minimization. Among the pretreatment methods, alkaline, thermal and thermochemical pretreatments are effectual ones. Considering the effect of thermal pretreatment, microwave technology in which the sample reaches to elevated temperatures very rapidly is a very new pretreatment method. However no previous research has been conducted to test the effectiveness of microwave (MW) irradiation combined with alkaline pretreatment. Since both of these techniques seem to be highly effective, their combination can act synergistically and even more efficient method can be obtained.

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Citation Formats
I. Doğan, “Combination of alkaline solubilization with microwave digestion as a sludge disintegration method: effect on gas production and quantity and dewaterability of anaerobically digested sludge ,” M.S. - Master of Science, Middle East Technical University, 2008.