Release Time:2019-03-12  Hits:

Indexed by: Journal Article

Date of Publication: 2017-02-01

Journal: FUEL

Included Journals: EI、SCIE

Volume: 189

Page Number: 57-65

ISSN: 0016-2361

Key Words: Lignite; Catalytic steam gasification; Hydrogen-rich gas; Tar removal; Decoupled gasification; Triple bed

Abstract: Catalytic steam gasification of an Inner Mongolia lignite for hydrogen-rich gas production was investigated in a decoupled triple bed reaction system with olivine and Ni/olivine as both solid heat carrier and in-situ tar cracking/reforming catalyst. In the system, tar cracking/reforming, pyrolysis/gasification, and char combustion reactions are decoupled into three separated reactors, i.e. a reformer, a fuel reactor and a combustor, which are connected in series by solid heat carrier. The system configuration provides an option to strengthen tar cracking/reforming reaction to improve hydrogen-rich gas production and tar removal. Specifically, using olivine and Ni/olivine in a mass ratio of 1:1 as circulating bed material and in-situ tar cracking/reforming catalyst, a product gas with the H-2 concentration of 51.7 vol.% and the tar content of 2.2 g/Nm(3) has been obtained at the pyrolyzer temperature of 700 degrees C, reformer temperature 850 degrees C, steam to carbon mass ratio (S/C) 1.2, and ratio of bed material circulating rate to coal feeding rate (C/F) 8.0. Nevertheless, the gasification performance suffered from the limited char steam gasification. (C) 2016 Elsevier Ltd. All rights reserved.