Hydrogen and syngas production from municipal solid waste (MSW) gasification via reusing CO2

Hydrogen and syngas production from MSW steam gasification with reusing CO2 has been conducted in this study. Two key parameters of gasification temperature and CO2/steam ratio in ranges of 1000-1100 °C and 0.5-3 are taken into consideration. The experiments reveal that increasing CO2/steam ratio in the range of 0.5 and 2.5 increases both H2 and CO molar yield. At the same time, the CO2 conversion efficiency rises. It indicates that Boudouard reaction and water gas reaction proceed independently in the gasification process. With the conditions of CO2/steam ratio = 2.5 and 1000 °C, the CO2 conversion efficiency augments to 50.22% and the maximum H2 molar yield of 18.82 mol/kg-msw can be observed. Under this condition, the highest values of 63.19% for CGE, 0.95 Nm3/kg-msw for gas yield and 12.41 MJ/Nm3 for LHV are obtained. In the steam-only atmosphere, there exist maximum values for H2 molar yield and gas yield as well. The values of both CGE and CCE are lower than those under the steam-CO2 atmosphere. In conclusion, MSW gasification with the addition of CO2 simultaneously has the advantages of waste-to-energy, reusing CO2 and producing hydrogen and syngas.