BIOGAS PRODUCTION FROM WATER HYACINTH (Eichhornia crassipes (Mart.) CO-DIGESTED WITH POULTRY MANURE

Abstract

The use of renewable energy sources can contribute to solve the present and future energy problems. Among the alternative energy sources, biogas production from green energy crops and organic waste has worldwide application as it yields a good quality fuel and fermented slurry, which may be used as a manure or soil conditioner. In this study, Biogas Production from Water Hyacinth (Eichhornia crassipes) Co-digestion with Poultry Manure in five mix ratios was evaluated under mesophilic condition (38ºC) using a batch digester for 18 days. In all treatments the parameters total solids moisture contents, volatile solids, pH and organic carbon were measured before and after digestion. For the experimental design, different mix ratios were adopted for the five substrate employed. All measured physico-chemical parameters of each treatments significantly varied between before and after AD, and also the rate of variation of these parameters before and after AD varied between treatments. Gas production was measured in all of the treatment types from the first day of the digestion experiment and went to zero at about 18 days in all treatments . Assessment of cumulative biogas production revealed that the decrease in %C AD was in order of WH 100% (14.81%)> 25% PM +75%WH (12.73%) >50% PM +50% WH (7.30%) >75% PM +25%WH (7.16%) > 100%PM (3.73%) suggesting more digestion of treatments by bacteria for either production of biogas or their own metabolic use in a treatments sole of 100% PM . The values of initial %VS ranged from 16.51% to 21.61%. After AD, the %VS ranged from 12.532 to 15.4592%. The total solids (TS) content of all mix ratios before AD was between 25.2 ±0.07 to 28.2±0.08). The maximum initial TS (28.2%) was measured in mixed treatment ration of (50%PM+50%WH) before anaerobic digestion. The biogas production started on the 1st day and stopped on the 18th day, recording its highest value of 298 L on the 3rd day. For the PM single-substrate digestion, gas production started on the 1st day and stopped on the 18th day. Evaluating biogas yield for co-digestion of PM with WH digestion mix 50% WH: 50% PM recorded the highest daily biogas yield of 298 L on the 3rd day.