Integrated Process of Coal Fast Pyrolysis in a Fluidized Bed Reactor With Reforming Reaction of Simulated Fuel Gas to Promote Light Tar Evolution

Chao Li,Jianmeng Cen,Mengxiang Fang,Qike Yan,Zhongyang Luo

doi:10.3389/fenrg.2021.717470

Abstract

The evolution behavior of the light tar during coal fast pyrolysis under inert gas, simulated fuel gas (SFG) atmosphere, and catalytic reformation of simulated (CRS) fuel gas over Ni/Al2O3 was studied in this article. The light tar was recovered from the distillation of the crude tar at the temperature of 300°C and subsequently subjected to detection through the GC-MS analysis. It was found that both SFG and CRS over Ni/Al2O3 significantly enhanced the light tar yield, but a little effect was shown on the heavy tar yield. According to the molecular structure characteristics, the compounds in the light tar could be classified into several groups: aromatic components, phenol components, aliphatic components, heteroatom components, and O-containing components (phenol compounds excluded). It was demonstrated that the selectivity of each component in the light tar varied significantly with the pyrolysis atmosphere and temperature. The evolution of the aromatic components took the dominant role in the light tar produced at high temperature. The SFG and CRS contributed markedly to enhancing the evolution of the O-aromatic components in the light tar, whereas they suppressed the evolution of the O-aliphatic components and the phenol components in the light tar at high temperature.

Highlights

More tar yield was normally obtained during the coal fast pyrolysis in a fluidized bed reactor for industry (Gonenc et al, 1990)
The coal fast pyrolysis in a fluidized bed reactor integrated with the catalytic reformation of simulated fuel gas (CRS), a mixture of H2, CH4, CO, and CO2, was deployed over the Ni/Al2O3 catalyst to confirm the promotion of the light tar yield
The evolution behavior of the light tar during the coal fast pyrolysis at 500–800°C in a fluidized bed reactor under N2, simulated fuel gas (SFG), and CRS over Ni/Al2O3 was investigated in this article

Summary

INTRODUCTION

To alleviate the pressure on the environment pollution from the direct coal fired power generation, some effective efforts were paid to high-valued and clean coal utilization (Ding et al, 2020). The coal fast pyrolysis in a fluidized bed reactor integrated with the catalytic reformation of simulated fuel gas (CRS), a mixture of H2, CH4, CO, and CO2, was deployed over the Ni/Al2O3 catalyst to confirm the promotion of the light tar yield. The coal pyrolysis both under the simulated fuel gas (SFG) atmosphere and under the N2 atmosphere was performed to further unveil the roles of SFG and CRS, respectively. The hot volatile products that evolved from the bituminous coal fast pyrolysis in the reactor were carried by the fluidizing gas into the tar recovery system. All the obtained GC-MS data were subjected to a systematical analysis according to the characteristics of the aromatic ring structure of molecular of compounds

RESULTS AND DISCUSSION

CONCLUSION

DATA AVAILABILITY STATEMENT