Thermodynamic Analysis of Producing Hydrogen by Sorption Enhanced Steam Reforming Process of Raw Coke Oven Gas

Thermodynamic analysis of producing hydrogen by the steam reforming process of raw coke oven gas(RCOG)was carried out using Aspen Plus software.It was found that the normal pressure was the best pressure for hydrogen-producing reaction by the steam reforming of RCOG without CO2 sorbent(i.e., ordinary reforming)and with CO2 sorbent of CaO(i.e., sorption-enhanced reforming). With increasing temperature and the ratio of steam to carbon(nS/nC), the amount and concentration of H2 increased, while they changed slightly after nS/nC was over 3. The addition of CaO enhanced the reforming reaction process, resulting in the decrease of the best reaction temperature and the increase of the amount and concentration of H2. Compared with those by ordinary reforming, the best temperature for the reaction by sorption-enhanced reforming with nCaO/nC=1 dropped from 650℃ to 450℃, the amount of H2 increased from 186 mol to 212 mol per 100 mol RCOG, the volume fraction of H2 increased from 74% to 97%, and the energy consumption of producing hydrogen decreased from 2.26 kW•h/m3 to 2.00 kW•h/m3, when nS/nC=3. © 2019, Editorial Department of Journal of Northeastern University. All right reserved.