Title: | Optimization of alkaline hydrothermal pretreatment of biological sludge for enhanced methane generation under anaerobic conditions |
Author(s): | Perendeci NA; Ciggin AS; Kokdemir Unsar E; Orhon D; |
Address: | "Environmental Engineering Department, Akdeniz University, 07058 Antalya, Turkey. Electronic address: aperendeci@akdeniz.edu.tr. Environmental Engineering Department, Akdeniz University, 07058 Antalya, Turkey. Environmental Engineering Department, Near East University, 99138 Nicosia/TRNC Mersin 10, Turkey" |
DOI: | 10.1016/j.wasman.2020.03.033 |
ISSN/ISBN: | 1879-2456 (Electronic) 0956-053X (Linking) |
Abstract: | "This paper investigated the effect of alkaline hydrothermal pretreatment (HTP) on the hydrolysis, biodegradation and methane generation potential of waste activated sludge (WAS). A multi-variable experimental approach was designed, where initial solids content (1-5%), reaction temperature (130-190 degrees C), reaction time (10-30 min.) and caustic concentration (0-0.2 mgNaOH/mgVS) were varied in different combinations to assess the impact of alkaline HTP. This process significantly enhanced the hydrolysis of organic compounds in sludge into soluble fractions, whereby increasing the chemical oxygen demand (COD) leakage up to 200-900% with the 17-99% solubility. It boosted volatile solids (VS) biodegradation up to 40%, which resulted in a parallel increase in methane generation from 216 mLCH(4)/gVS to as high a 456 mLCH(4)/gVS methane generation basically relied on the conversion of solubilized COD. Alkaline HTP process was optimized for the maximum methane production. Optimum conditions were obtained at 190 degrees C reaction temperature, 10 min. reaction time, 0.2 mgNaOH/mgVS and 5% dry matter content. Under these conditions, 453.8 mLCH(4)/gVS was predicted. Biochemical methane potential (BMP) value was determined as 464 mLCH(4)/gVS supporting predictive power of the BMP model. The biodegradability compared to the untreated raw WAS was enhanced 78.2%" |
Keywords: | Anaerobiosis Biological Oxygen Demand Analysis Hydrolysis *Methane *Sewage Alkaline hydrothermal pretreatment Methane generation Process optimization Waste activated sludge; |
Notes: | "MedlinePerendeci, N A Ciggin, A S Kokdemir Unsar, E Orhon, D eng 2020/04/06 Waste Manag. 2020 Apr 15; 107:9-19. doi: 10.1016/j.wasman.2020.03.033. Epub 2020 Apr 2" |