Production of flammable gases from cattle manure via pyrolysis using CO2 as an oxidant

Abstract

To valorize disposed animal manure into flammable gases, pyrolysis of cattle manure (CM) was investigated in this study. To make this process more efficient and environmentally benign, CO2, a greenhouse gas, was harnessed as a reactive gas. In CO2-assisted pyrolysis of CM, enhanced CO production was observed, compared to pyrolysis from inert condition (N-2). The gas-phase reactions between CO2 and gaseous biocrude produced from CM thermolysis led to improved CO formation. In reference to the case of lignocellulosic biomass (rice straw), 5 times more CO production was observed from CM pyrolysis under CO2. For an in-depth study of CO2 functionality as an oxidant, the effects of operational parameters on syngas formation were considered. The key parameter to activate the functionality of CO2 was temperature. These results offer that CO2 and CM could be considered promising reactants to produce value-added syngas in line with mitigation of pollutant emissions through a pyrolysis platform.