Association between Biogas Quality and Digester Temperature for Selected Animal Dung-Aided Water Hyacinth Digestion Mixes

Abstract

In this study, the association between biogas qulaity and digester temperature for selected animal dung-aided water hyacinth digestion mixes was  evaluated. Substrates utilized in this study are water hyacinth (WH), poultry manure (PM) and cow dung (CD) and pig dung (PD). Thirty-one (31) co-digestion mix ratios were used in this study. The temperature ranged from 28.6 to 32.2 0C for the PD-aided WH digestion, 28.2 to 31.4 0C for the CD-aided WH digestion and 28.2 to 31.8 0C for the PM-aided WH digestion. This shows that the digestion process occurred within the mesophilic  temperature range. The data obtained were analyzed using non-linear parameter estimation. The results revealed that the PM-aided WH mix produced more gas but with less methane content compared to the CDaided and PD-aided WH digestion mix. The results further revealed that the best quality of gas produced by the PD-aided WH digestion. The association between the temperature and gas quality was positive suggesting that an increase in temperature within the digestion leads to an increase in the quality of gas produced.

Keywords: Biogas quality, temperature, co-digestion, animal dung, water hyacinth