Impacts of sewage sludge codisposal on waste degredation in aerobic and anaerobic bioreactors

Abstract

Due to economical, endustrial and technological developments, waste and wastewater sludge productions are increasing gradually all over the world. This situation constitutes to the problem of sustainable solid waste and sludge disposal. Especially diffuculties in finding new landfill spaces, high cost of wastewater sludge management and environmental concerns are forced to find a new method for disposal. Although there are many methods such as incineration, surface disposal and composting, codisposing of wastewater sludge with MSW in the aerobic and anaerobic bioreactors are most used and economical way. Therefore, the objective of this study was to obtain information about sludge codisposal with MSW in the aerobic and anaerobic bioreactors in order to evaluate and determine an efficient and cost-effective landfill management system by utilizing two stage laboratory experiments. These stages include, the lab-scale reactor set-up in order to determine optimum solid waste to sludge ratios by using anaerobic bioreactors and then pilot scale reactor set-up in order to understand the effect of sludge addition on waste stabilization process by using aerobic and anaerobic bioreactors. The results of this study showed that in the lab-scale reactors, codisposal of wastewater sludges with MSW is a very promising method. This method accelerates waste stabilization rates in the anaerobic bioreactors while the energy potential of the sludge is used beneficial. In the pilot scale reactors this study showed that, aeration is a feasible way to treat leachate, fastens stabilization rate and provides rapid removal of organics and nitrogen. On the other hand, CH4 production in the anaerobic was more promising.