eprintid: 13395 rev_number: 2 eprint_status: archive userid: 1 dir: disk0/00/01/33/95 datestamp: 2023-11-10 03:27:57 lastmod: 2023-11-10 03:27:57 status_changed: 2023-11-10 01:51:04 type: article metadata_visibility: show creators_name: Ghaleb, A.A.S. creators_name: Kutty, S.R.M. creators_name: Ho, Y.-C. creators_name: Jagaba, A.H. creators_name: Noor, A. creators_name: Al-Sabaeei, A.M. creators_name: Almahbashi, N.M.Y. title: Response surface methodology to optimize methane production from mesophilic anaerobic co-digestion of oily-biological sludge and sugarcane bagasse ispublished: pub keywords: anaerobic digestion; biogas; biotransformation; hydroxide; methanogenesis; optimization; petroleum; pH; refining industry; response surface methodology; sludge; sodium; sugar cane note: cited By 50 abstract: Oily-biological sludge (OBS) generated from petroleum refineries has high toxicity. Therefore, it needs an appropriate disposal method to reduce the negative impacts on the environment. The anaerobic co-digestion process is an effective method that manages and converts organic waste to energy. For effective anaerobic digestion, a co-substrate would be required to provide a suitable environment for anaerobic bacteria. In oily-biological sludge, the carbon/nitrogen (C/N) ratio and volatile solids (VS) content are very low. Therefore, it needs to be digested with organic waste that has a high C/N ratio and high VS content. This study investigates the use of sugarcane bagasse (SB) as an effective co-substrate due to its high C/N ratio and high VS content to improve the anaerobic co-digestion process with oily-biological sludge. The sugarcane bagasse also helps to delay the toxicity effect of the methane bacteria. Batch anaerobic co-digestion of oily-biological sludge was conducted with sugarcane bagasse as a co-substrate in twelve reactors with two-liter capacity, each under mesophilic conditions. The interaction effect of a C/N ratio of 20-30 and a VS co-substrate/VS inoculum ratio of 0.06-0.18 on the methane yield (mL CH4/g VSremoved) was investigated. Before the anaerobic digestion, thermochemical pre-treatment of the inoculum and co-substrate was conducted using sodium hydroxide to balance their acidic nature and provide a suitable pH environment for methane bacteria. Design and optimization for the mixing ratios were carried out by central composite design-response surface methodology (CCD-RSM). The highest predicted methane yield was found to be 63.52 mL CH4/g VSremoved, under optimum conditions (C/N ratio of 30 and co-substrate/inoculum ratio of 0.18). © 2020 by the authors. date: 2020 publisher: MDPI official_url: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85082558631&doi=10.3390%2fsu12052116&partnerID=40&md5=345f91499c8b73d9b7e8e5bbc651882d id_number: 10.3390/su12052116 full_text_status: none publication: Sustainability (Switzerland) volume: 12 number: 5 refereed: TRUE issn: 20711050 citation: Ghaleb, A.A.S. and Kutty, S.R.M. and Ho, Y.-C. and Jagaba, A.H. and Noor, A. and Al-Sabaeei, A.M. and Almahbashi, N.M.Y. (2020) Response surface methodology to optimize methane production from mesophilic anaerobic co-digestion of oily-biological sludge and sugarcane bagasse. Sustainability (Switzerland), 12 (5). ISSN 20711050