Efficiency Penalty Analysis for Pure H_2 Production Processes with CO_2 Capture

摘要

The conventional steam-reforming (CSR)process is a major process for the production of pure hydrogen from natural gas with CO_2 as the main by-product.In this work,based on the CSR process,several alternative H_2-producing processes with CO_2 capture are simulated and analyzed.The alternative processes capture the CO_2 by concentrating the CO_2 through the approaches including burning some of the separated H_2 instead of CH_4 in the furnace,using pure oxygen instead of air for the combustion of fuel gas,applying a prereformer to reduce the usage of pure oxygen,and applying an H_2-membrane in the steam reformer to separate pure H_2.The reactors of the CSR process and the alternative processes with CO_2 capture were simulated based on the kinetic models of the reactions.The CSR process and the alternative processes were evaluated in terms of the thermodynamic efficiency,the amount of high pressure (HP)H_2 produced per mole of CH_4,the amount of CO_2 produced per mole of HP H_2,and the CO_2 captured per mol of HP H_2.The efficiency penalties for CO_2 capture of the alternative processes were compared and discussed.