Effect of temperature and bagasse addition on anaerobic co-digestion of brewery waste by biochemical methane potential test

Abstract

The aim of this study was to identify the best operating conditions for sustainable and integrated management of waste generated in the brewing industry. For this purpose, biochemical methane potential (BMP) tests of brewery wastewater monodigestion (BWW) and co-digestion of BWW with bagasse (BSG) were carried out to determine the biodegradability and methane generation potential in mesophilic and thermophilic ranges, at laboratory scale. The results showed that the addition of BSG inhibits the anaerobic digestion process as well as methane production in both mesophilic and thermophilic. In addition, significantly lower values of volatile solids (VS) removal were obtained when BSG was added. BWW monodigestion achieves a VS removal of 95.41% and 86.36% in mesophilic and thermophilic range respectively. While in the co-digestion of BWW with BSG the value was 79.46% and 75.48%, in mesophilic and thermophilic range, respectively. For methane yield, the trend was similar, in the BMP tests for BWW 104.07 and 170.11 mLCH4/gVS were recorded in mesophilic and thermophilic range respectively, while the samples with bagasse only reached 22.86 mLCH4/gVS in mesophilic and 20.62 mLCH4/gVS in thermophilic. Therefore, BGS added without any pre-treatment would not be suitable as a cosubstrate for AD in both temperature ranges studied.