EVALUATION OF THE EFFECT OF SODIUM HYDROXIDE SOLUTION ON BIOGAS YIELD OF POULTRY WASTE AND THE DIGESTATE

Abstract

The negative effects of waste on human lives and in our environments have raised the need for the waste to be reused as a source of renewable energy. This research investigates the viability of digesting poultry waste (PW) anaerobically to generate biogas, a renewable energy. It also finds out the effect of adding alkaline solution (NaOH) on biogas and methane yield of the poultry waste during anaerobic digestion. Two digesters of 50 litres capacity each were set up labeled A and B, and were batch loaded with samples A and B respectively. Sample A being a mixture of 19 kg of PW and 19 litres of water while sample B is the same mixed volume ratio of PW and water as in sample A but with the addition of 380 ml of 1M NaOH. Daily gas yield was obtained from the two digesters for retention period of 30 days, the temperature and pH was also recorded daily. The peak yield for sample A was recorded on day 23 to be 0.0392 m3 while sample B peak yield of 0.0522 m3 was recorded on day 18. The cumulative biogas yields at the end of the retention period were 0.5511 m3 and 0.6070 m3 for digesters A and B respectively. The coefficient of correlation R2 between the gas yields of the samples is 0.9657. The biogas produced from the decomposition of sample B yielded 62.70% of methane which is higher than the methane in the biogas produced from the decomposition of sample A being 59.67%.