Effects of atmosphere and post catalyst on pyrolysis characteristics of Pingshuo bituminous coal

Abstract

In order to lighten the tar from coal pyrolysis, the effects of N2, CH4 and H2 atmosphere on the pyrolysis characteristics of Pingshuo bituminous coal were investigated in a small fluidized bed, and Ni-based catalyst was placed downstream of coal pyrolysis to catalyze the upgrading of tar. The results show that both H2 and CH4 atmosphere can improve the conversion of coal pyrolysis and improve the yield of pyrolysis tar. Compared with CH4 atmosphere, the post placed Ni-based catalyst in CH4 atmosphere can increase the taryield by 10%, increase the gas yield and H2 yield, and transform the pyrolysis tar to the light direction. Through simulated distillation and GC-MS analysis, compared with N2 atmosphere, CH4, H2 atmosphere and CH4 + Ni increased the relative contents of naphtha, phenol oil, naphthalene oil, wash oil and anthracene oil, and the increase showed that CH4 + Ni > H2 > CH4, while the asphalt content decreased. Compared with CH4, the relative contents of aromatic hydrocarbons and aliphatic hydrocarbons increased significantly under CH4 + Ni.