Process route and economic analysis of hydrogen production from oil shale

Abstract

The development of hydrogen production process can provide a new way to use oil shale with high value and low carbon emission. However, the current research only considers hydrogen as a small amount of by-product during oil shale processing, and there is a lack of understanding of the technology aimed at hydrogen production. The technical route of hydrogen produced from oil shale is proposed in this study. The complete process from oil shale raw material to hydrogen product is designed, including six modules of pyrolysis, combustion, gasification, reforming, purification, and flue gas treatment. The effects of key operating parameters on oil shale transformation, product composition, and energy consumption characteristics are analyzed. The results show that the proposed route in this study can produce industrial hydrogen with 99% purity. Under the condition that the CO2 removal rate is 90% and the exhaust gas meets the emission standard, the efficiency of hydrogen production from oil shale is 6.26 Nm 3 -H2/t-shale, with a system energy efficiency of 75.61% and an exergy efficiency of 46.43%. Economic analysis shows that the annual profit and return on investment of this process are significantly higher than that of other shale refining processes. This research provides technology options for hydrogen production and the high-value, clean, and low-carbon utilization of oil shale.