Kinetic Study of CO₂ Gasification of Coal Chars

Abstract

The CO2 gasification of three coal chars were investigated for determining the gasification reactivity and the kinetic parameters. Experiments were conducted in a fluidized-bed reactor at temperature of 1173 k, 1273 k and 1373 k at atmospheric pressure. Gasification kinetic parameters of the samples were determined using Homogeneous model and shrinking-core model. It is found that the gasification reaction under chemical-reaction-rate control, the gasification reactivity of coal char are strongly dependent on the rank of coals and gasification temperature. Both models could describe CO2 gasification equally well, these kinetic values are comparable with the reported in the literature for the other chars under chemical control conditions.

Gasification of Shenhua Bituminous Coal with CO2: Effect of Coal Particle Size on Kinetic Behavior and Ash Fusibility

“…Char gasification is usually a slower process than pyrolysis and is the rate-limiting step of the whole process; therefore, the knowledge of gasification kinetics is vital for designing gasification reactors [2]. Thus, gasification kinetic analyses are the starting point for the design, optimization, and operation of gasifiers [3,4]. The most frequently utilized gasification agents include O 2 , air, H 2 O, and CO 2 , among which steam is the most widely used [2].…”