Three-dimensional numerical simulation of fast pyrolysis of coal in pressurized spout-fluid bed

doi:10.7523/j.issn.2095-6134.2020.02.010

Abstract

Abstract: Numerical simulation of pressurized fast pyrolysis process of coal in a pilot-scale reactor with the capacity of 50 kg/h was carried out. Characteristics of structural parameters, such as reactor height, coal feeding inlet position, pyrolysis pressures (0.1, 0.3, and 0.5 MPa), ratios of spouted gas to fluidized gas (0.2, 0.3,and 0.4), and particle size (0-3 and 0-6 mm), were investigated. The results are shown as follows. With the increase of pressure, the mixing of coal and semi-coke became worse while the gas yield increased. Keeping the fluidized gas Q_f unchanged, with the increase of spouted gas Q_s, the gas-solid flow became more intense, the particle temperature distribution became more uniform, and the particle outflow at the volatile outlet increased. Although increasing particle size reduced the particle outflow at the volatile outlet, it might weaken the mixing of coal and semi-coke.

Key words: pressurized grade conversion of coal, coal pressurized pyrolysis, spout-fluid bed, numerical simulation

CLC Number:

TK16

ZHOU Guanwen, ZHONG Wenqi, YU Aibing. Three-dimensional numerical simulation of fast pyrolysis of coal in pressurized spout-fluid bed[J]. , 2020, 37(2): 210-219.

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