Waste to energy: power generation potential of putrescible wastes by anaerobic digestion process at Hyderabad, Pakistan

Power generation from municipal solid waste plays significant role to mitigate the environmental pollution. The power generation potential of putrescible wastes (fruit, vegetable and yard wastes) was investigated at Hyderabad, Pakistan. In the first phase, methane potential of fruit, vegetable and yard wastes mixing at different ratios was determined to optimize best of one. In the second phase, methane potential of optimized ratio was further investigated through continuous stirrer tank reactor at hydraulic retention time of 20 days by using organic loading rate from 3 to 5% total solids (1.5–2.5 kg VS/m³/day). In the third phase of study, power generation potential of selected waste was estimated. The maximum methane potential (643 NmL/gVS, p ˂ 0.05) was obtained from fruit, vegetable and yard wastes when mixed at (1:1:1) by biochemical methane potential test system. Results of continuous digestion revealed that methane yield increased as organic loading rate was increased and obtained maximum methane yield of 525 NmL/gVS at 5% total solids (2.5 kg VS/m³/day). Moreover, from the results and findings of the study, it was estimated that about 907 MW/year power can be generated through anaerobic digestion of putrescible waste in Pakistan.