Effect of Biochar on Biogas Yield of Poultry Wastes

Abstract

This study investigates the effect of biochar as an additive on the anaerobic digestion of poultry droppings from layers and broilers. Six digesters (A, B, C, D, E, and F) with dry weight content of 100% layer wastes (control), 100% broiler wastes (control), 95% layer wastes + 5% biochar, 90% layer wastes + 10% biochar, 95% broiler wastes + 5% biochar, and 90% broiler wastes + 10% biochar were used for 31 days. The respective cumulative biogas yields of layer and broiler waste digestion were 17.9 L, 17.7 L, 21.8 L, 22.6 L, 21.3 L, and 22.0 L. This study revealed that biochar addition of 10% increased the biogas yield of both wastes by 26% and 24%, respectively. The methane content was highest in the biogas from digester F (68.12%), producing the least amount of hydrogen sulphide (0.84%). Consequently, broiler waste is found to be the most suited for biogas generation, especially when spiked with 10% biochar.