Thermodynamic calculation on the pyrolysis reactions of coke oven gas with multiple pyrolysis agents

Abstract

The reducing gas obtained from coke oven gas(COG) reforming is an important secondary energy source, which can replace fossil energy and contribute to the reduction of CO2 emission and sustainable development. The percentage of (H2+CO) and the ratio of H2/CO in the reducing gas are important parameters for the COG reforming. In the present work, the pyrolysis reactions of COG with O2, H2O, and CO2 were thermodynamically calculated and analyzed. The calculation results show that, (1) as only one kind of agent (O2, H2O, CO2) participate the reaction, when pyrolyzed with H2O or CO2, the percentage of (H2+CO) in the reducing gas was highest, and were 95.26%. The H2/CO in the reducing gas was highest when pyrolysis with H2O and was 3.73. (2) as two kinds of agent participate the reaction, the percentage of (H2+CO) in the reducing gas obtained by pyrolysis decreases with the proportion of O2 in the mixed gas increases. The H2/CO ratio in the reducing gas gradually decreases with increasing pyrolysis temperature. (3) in the ternary calculations of COG reforming, when the proportion of O2 is higher, the percentage of (H2+CO) is lower. When the proportion of H2O is higher and the proportion of CO2 is lower, the ratio of H2/CO is higher. The research contents and results may provide the theoretical guidance on the optimizing the COG reforming process and selection of pyrolysis agents for the development of the relative chemical and metallurgical industry.