<abstract xmlns="http://www.w3.org/1999/xhtml"><p>Large amounts of sludge are produced in biological wastewater treatment plants. Since the sludge is highly contaminated, it has to undergo proper stabilization before it is disposed or utilized in an environmentally safe way. On the whole, the aim of bacterial cell disintegration is the release of cell contents in the form of an aqueous extract. Chemical disintegration of surplus activated sludge by alkalization results in destruction and disruption of the flocs and microorganisms as well as increase concentration of organic matter in supernatant. The mesophilic anaerobic sewage sludge digestion is an established process, most often applied at medium and large municipal sewage treatment plants. Four major steps of anaerobic digestion are distinguished. The first hydrolysis step leads to solubilization of insoluble particulate matter and biological decomposition of organic polymers to monomers or dimers. The hydrolysis step is recognized as the rate-limiting step of the following second and third steps, the processes of acidogenesis and acetogenesis. Chemical disintegration activates biological hydrolysis and, therefore, it can significantly increase the stabilization rate of the secondary sludge. It has been shown that when the activated sludge was subjected to alkalization to pH 9.0 value, the COD concentration increased from 101 to 530 mg/dm<sup>3</sup> in sludge supernatant. The paper presents a potential application of chemical disintegration for sewage sludge (mainly activated sludge) to upgrading biogas production.</p></abstract>

Large amounts of sludge are produced in biological wastewater treatment plants. Since the sludge is highly contaminated, it has to undergo proper stabilization before it is disposed or utilized in an environmentally safe way. On the whole, the aim of bacterial cell disintegration is the release of cell contents in the form of an aqueous extract. Chemical disintegration of surplus activated sludge by alkalization results in destruction and disruption of the flocs and microorganisms as well as increase concentration of organic matter in supernatant. The mesophilic anaerobic sewage sludge digestion is an established process, most often applied at medium and large municipal sewage treatment plants. Four major steps of anaerobic digestion are distinguished. The first hydrolysis step leads to solubilization of insoluble particulate matter and biological decomposition of organic polymers to monomers or dimers. The hydrolysis step is recognized as the rate-limiting step of the following second and third steps, the processes of acidogenesis and acetogenesis. Chemical disintegration activates biological hydrolysis and, therefore, it can significantly increase the stabilization rate of the secondary sludge. It has been shown that when the activated sludge was subjected to alkalization to pH 9.0 value, the COD concentration increased from 101 to 530 mg/dm3 in sludge supernatant. The paper presents a potential application of chemical disintegration for sewage sludge (mainly activated sludge) to upgrading biogas production.

Impact of Alkalization of Surplus Activated Sludge on Biogas Production

Institute of Engineering and Environmental Protection, Faculty of Materials and Environmental Sciences, University of Bielsko-Biala, ul. Willowa 2, 43-309 Bielsko-Biała, phone +48 33 827 91 57

Institute for Nanomaterials, Advanced Technology and Innovation, Technical University of Liberec, ul. Studentská 1402/2, 461 17 Liberec 1, Czech Republic, phone +420 485 353 006

Ecological Chemistry and Engineering S

{"article-title":"Impact of Alkalization of Surplus Activated Sludge on Biogas Production"}

Large amounts of sludge are produced in biological wastewater treatment plants. Since the sludge is highly contaminated, it has to undergo proper stabilization...

Impact of Alkalization of Surplus Activated Sludge on Biogas Production

Published Online: May 29, 2013

Page range: 343 - 351

DOI: https://doi.org/10.2478/eces-2013-0025

This content is open access.