Optimization of biogas slurry use for digestion of an admixture of kitchen waste and cattle dung
Loading...
Date
2011
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
CCSHAU
Abstract
Anaerobic digestion of kitchen waste and cattle dung was carried out in laboratory scale
batch mode reactors in two phases. In the first phase, anaerobic digestion with different mixture of
kitchen waste (KW) and cattle dung (CD) with 20% inoculum was carried out whereas in the
second phase, anaerobic digestion of mixture of KW and CD with different concentration of
inoculum was carried out. Five feedstock of which were made by mixing kitchen waste and cattle
dung at different mixing ratios of 0:1 (P1R1), 1:3 (P1R2), 1:1 (P1R3), 3:1 (P1R4) and 1:0 (P1R5)
were tested. The result showed that reactor P1R3 (50% KW + 50% CD) with kitchen waste and
cattle dung ratio of 1:1 gave the maximum (21.3 l/kg of solid substrate) biogas with volumetric
biogas production of 0.37 l/kg/d and methane yield of 0.092 m3/kg VS added with solid
conversion efficiency of 142 ml/g TS and 162 ml/g VS added. After completion of first phase, the
best mixture obtained was 50% KW + 50% CD (P1R3). In the second phase, this mixture was
digested with different concentrations of inoculums viz. 10%, 15%, 20% and 25%. The maximum
biogas yield was of (27.6 l/kg of solid substrate) observed in reactor P2R4 (50% KW + 50% CD
with 25% inoculum) with volumetric biogas production of (0.48 l/kg/d) and methane yield of
0.085 m3/kg VS added with solid conversion efficiency of 127 ml/g TS and 145 ml/g VS added.
Therefore, mixing ratio of 1:1 of kitchen waste and cattle dung was optimal for biogas yield,
methane yield and solid conversion efficiency with 25% inoculum.
Description
Keywords
Anaerobic digestion, Kitchen waste, Cattle dung, Biogas