Combined steam/dry reforming of bio-oil for H2/CO syngas production with blast furnace slag as heat carrier

Combined steam/dry reforming of bio-oil with blast furnace slag as heat carrier for the syngas production with the H-2/CO ratio of 3:1 for further methanation, was investigated. The increase of H2O addition can increase the total yield of H-2 and CO, but also increase the critical temperature at which 3:1-H-2/CO syngas was obtained, while the increase of CO2 addition can decrease the critical temperature, but the syngas yield was also decreased. When the steam/carbon (S/C) ratio was 3.0 and the CO2/carbon (CO2/C) ratio was 0.5, the critical temperature decreased to 804 degrees C, with the potential H-2 yield of over 90%. Although the addition of slag and how much slag to be added had almost no any thermodynamic effect on the combined reforming of bio-oil under the condition where higher potential H-2 yield can be obtained, the slag as heat carrier could supply all heat for the combined reforming process. When the added slag mass was 3.99 times bio-oil mass, the combined reforming at the S/C ratio of 3.0 and the CO2/C ratio of 0.5 can occur spontaneously for the production of 3:1-H-2/CO syngas. The present study could offer important guidance toward utilization of this novel process for further methanation. (C) 2020 Elsevier Ltd. All rights reserved.