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

Download
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.

Suggestions

Two-phase anaerobic digestion of semi-solid organic wastes
Doğan, Eylem; Demirer, Göksel Niyazi; Department of Environmental Engineering (2008)
The objective of this study is to illustrate that phase separation improves the efficiency of an anaerobic system which digests semi-solid organic wastes. Organic fraction of municipal solid waste (OFMSW) was the semi-solid organic waste investigated. In the first part of the study, the optimum operational conditions for acidified reactor were determined by considering the volatile solid (VS) reductions and average acidification percentages at the end of two experimental sets conducted. Organic loading rate...
Municipal sludge minimization: evaluation of ultrasonic and acidic pretreatment methods and their subsequent effects on anaerobic digestion
Apul, Onur Güven; Sanin, Faika Dilek; Department of Environmental Engineering (2009)
Sludge management is one of the most difficult and expensive problems in wastewater treatment plant operation. Consequently, ‘sludge minimization’ concept arose to solve the excess sludge production by sludge pretreatment. Sludge pretreatment converts the waste sludge into a more bioavailable substrate for anaerobic digestion and leads to an enhanced degradation. The enhanced degradation results in more organic reduction and more biogas production. Therefore, sludge pretreatment is a means of improving slud...
Investigation of thin semiconductor coatings and their antimicrobial properties
Erkan, Arcan; Karakaş, Gürkan; Department of Chemical Engineering (2005)
Regular disinfection of surfaces is required in order to reduce the number of microorganisms, unable to transmit infections and maintaining the surfaces sterilized. For this purpose, antimicrobial thin film coatings on the various surfaces such as glass and ceramic surfaces, capable of killing harmful microorganisms are being investigated. Generally a semiconducting material which can be activated by UV light tends to exhibit a strong antimicrobial activity. With holes (h+) and hydroxyl radicals (OH*) gener...
Co-treatment of hazardous compounds in anaerobic sewage sludge digesters
Özkan Yücel, Umay Gökçe; Gökçay, Celal Ferdi; Department of Environmental Engineering (2008)
Xenobiotic compounds, which are exclusively man made, are produced in large quantities every year and released to the environment. Besides, anaerobic sludge digestion offers advantage in co-treatment of hazardous substances produced by the industry. The performance of the digesters can be monitored by modeling efforts. In this study, Anaerobic Digestion Model No.1 (ADM1) was calibrated, and validated for full-scale digester, lab-scale digester, and lab-scale digester seeded with totally different anaerobic ...
Enhancing the performance of anaerobic digestion of dairy manure through phase-separation
Yilmaz, Vedat; Demirer, Göksel Niyazi (Wiley, 2008-09-01)
Anaerobic digestion (AD) is an effective way to convert animal manures into profitable by-products while simultaneously reducing, the pollution of water, air, and soil caused by these wastes. Conventional high-rate anaerobic reactors cannot effectively process animal manures with high solids-containing wastes. The two-phase configuration for AD has several advantages over conventional one-phase processes, e.g., increased stability of the process, smaller size and cost efficient process configurations. In th...
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.