Effect of coal type on gasification in pressurized drop tube furnace

Citation
Hc. Cho et al., Effect of coal type on gasification in pressurized drop tube furnace, INT J ENERG, 25(5), 2001, pp. 427-438
Citations number
18
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Environmental Engineering & Energy
Journal title
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
ISSN journal
0363-907X → ACNP
Volume
25
Issue
5
Year of publication
2001
Pages
427 - 438
Database
ISI
SICI code
0363-907X(200104)25:5<427:EOCTOG>2.0.ZU;2-N
Abstract
In order to understand the effect of coal type on coal gasification process at 15 atmospheric pressure of pressurized drop tube furnace (PDTF), a nume rical study was conducted. Eulerian approach is used for the gas phase, whe reas Lagrangian approach is used for the solid phase. Turbulence is modelle d using the standard k-epsilon model. The turbulent gas-phase combustion mo del incorporates the eddy dissipation model. One-step two-reaction model is employed for the devolatilization. Effect of coal type on carbon conversion at the same coal feed rate and gas flow rate cannot be verified due to the variation of equivalence ratio acc ording to coal composition. Therefore, the same equivalence ratio is chosen to evaluate the effect of coal type on gasification. It is found that the volatile release based on experimental results should be taken in computati ons to predict accurate carbon conversion, especially in coal gasification due to the low gasification reaction. Even at over 1500 K and 15 atmospheri c pressure, at which reactions are primarily diffusion-controlled the exit carbon conversion varies with the coal type. The temperature gradient in ne ar-burner region becomes gentle with increasing proximate volatile and mois ture contents, but the volatiles released can make the temperature gradient steep by means of the fast reaction with oxygen. Copyright (C) 2001 John W iley & Sons, Ltd.