Enhancement of methane production from co-digestion of chicken manure with agricultural wastes

The potential for methane production from semi-solid chicken manure (CM) and mixture of agricultural wastes (AWS) in a co-digestion process has been experimentally evaluated at thermophilic and mesophilic temperatures. To the best of author's knowledge, it is the first time that CM is co-digested with mixture of AWS consisting of coconut waste, cassava waste, and coffee grounds. Two types of anaerobic digestion processes (AD process) were used, process 1 (P1) using fresh CM (FCM) and process 2 (P2) using treated CM (TCM), ammonia stripped CM, were conducted. Methane production in P1 was increased by 93% and 50% compared to control (no AWS added) with maximum methane production of 502 and 506 mL g−1 VS obtained at 55 °C and 35 °C, respectively. Additionally, 42% increase in methane production was observed with maximum volume of 695 mL g−1 VS comparing P2 test with P2 control under 55 °C. Ammonia accumulation was reduced by 39% and 32% in P1 and P2 tests.