Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8870095 | Waste Management | 2018 | 7 Pages |
Abstract
This paper analyses time (30 and 60â¯min) and temperature (120-190â¯Â°C) effects of intermediate thermal hydrolysis (ITHP) in a two-step anaerobic digestion of waste activated sludge (WAS) with and without wheat straw as a co-substrate. Effects were analyzed by measuring biochemical methane potential for 60â¯days and assessing associated kinetic and chemical data. Compared to non-treatment, ITHP increased the secondary step methane yield from 52 to 222â¯Lâ¯CH4â¯kgâ¯VSâ1 and from 147 to 224â¯Lâ¯CH4â¯kgâ¯VSâ1 for pre-digested WAS and pre-co-digested WAS respectively at an optimum of 170â¯Â°C and 30â¯min. The hydrolysis coefficients (khyd) increased by up to 127% following treatment. Increasing ITHP time from 30 to 60 min showed ambiguous results regarding methane yields, whilst temperature had a clear and proportional effect on the concentrations of acetic acid. The energy balances were found to be poor and dewatering to increase total solids above the values tested here is necessary for this process to be energetically feasible.
Keywords
PDSUltimate methane yieldROAWWTPEPSTHPVFAADPSTPVolatile fatty acidsWASWastewater treatment plantTotal solidsvolatile solidsstandard temperature and pressureKineticsWaste activated sludgeBMPExtracellular polymeric substancesAnaerobic digestionThermal hydrolysisbiochemical methane potentialPre-treatmenthigh performance liquid chromatographyHPLC
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Geotechnical Engineering and Engineering Geology
Authors
Michael Bjerg-Nielsen, Alastair James Ward, Henrik Bjarne Møller, Lars Ditlev Mørck Ottosen,