GUO Erguang;WANG Guijin;CHEN Jiaqi;JIN Lijun;HU Haoquan;

• 1:Institute of Coal Chemical Engineering
• 2:School of Chemical Engineering
• 3:Dalian University of Technology

Abstract：

The pyrolysis experiments of Naomaohu coal(NMH) at atmospheric pressure and 1.5 MPa H_(2 )and N_2 were carried out in a pressurized fixed-bed reactor. The products yield and composition and char structure under H_2 and N_2 were comparatively investigated by various characterization methods. The CO_2 gasification reactivity of char was studied by a thermogravimetric analyzer. The results indicate that pyrolysis of coal in pressurized H_2 can effectively increase the yield of CH_4 and C_2-C_3, from 53.5 and 16.6 mL/g in atmospheric N_2 to 345.6 and 20.8 mL/g in pressurized H_2, respectively, during the coal pyrolysis at 800 ℃. Tar yield and quality is also effectively improved. Compared coal pyrolysis at 600 ℃ under 1.5 MPa H_2 with that under atmospheric pressure N_2, the tar yield increases from 19.3% to 22.8%, the aliphatic hydrocarbon content decreases from 35.5% to 14.8%, the monocyclic aromatic hydrocarbon content increases from 8.3% to 28.9%, and the light tar content and yield increases to 95% and 21.8%, respectively. The results of N_2 adsorption and Raman spectroscopy show that the specific surface area and pore volume of the char in pressurized hydropyrolysis increase from 40 m~2/g and 0.05 cm~3/g in atmospheric N_(2 )to 289 m~2/g and 0.16 cm~3/g, and the pore structure is significantly developed. This is beneficial to the CO_2 gasification reaction of char. The graphitization degree and the proportion of large aromatic ring increase, which is not conducive to the gasification reaction of char. The thermogravimetric analysis results show that the gasification reactivity of char from pressurized hydropyrolysis is significantly higher, which indicates that pore structure plays a main role in the influence on the CO_2 gasification reactivity of the char.

Key Words： coal;hydropyrolysis;tar;char structure;gasification reactivity

Abstract:

Keywords:

Foundation: 国家重点研发计划资助项目(2016 YFB0600301);; 大连市重点领域创新团队支持计划资助项目(2019RT10)

Authors: GUO Erguang;WANG Guijin;CHEN Jiaqi;JIN Lijun;HU Haoquan;

DOI: 10.13226/j.issn.1006-6772.23031404

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