Coal gasification with a subcritical steam in the presence of a CO2 sorbent: products and conversion under transient heating

Two fluid model using kinetic theory for modeling of one‐step hydrogen production gasifier

“…CaO is not only as accepter of CO 2 and other pollutants such as H 2 S, but also as catalyst to achieve reforming, gas water shift reaction and coal gasification simultaneously in a single reactor. 43,44 Ohtsuka et al 45 found that the addition of calcium catalyst can also decrease the reaction temperature and increase the gasification rate.…”

Kinetics of steam gasification of bituminous coals in terms of their use for underground coal gasification

“…In the vast majority of cases, the examinations of gasification kinetics are conducted for coal chars, with the temperature at which they are obtained being very important. The impact of temperature and pressure at which the process is conducted on the rate of coal and lignite gasification as well as the yields of gaseous product still remains a valid problem [13][14][15][16]. The presented examinations confirm that temperature is one of the more important factors influencing the carbon conversion degree and coal char gasification rate.…”

Hydrogen Production from a Fluidized‐bed Coal Gasifier with In Situ Fixation of CO2–Part I: Numerical Model

“…The common terms in both the gas phase equations and particle phase equations indicate the gasparticle interactions, such as the source term S, Eqs. (1)(2)(3)(4) and S p , Eq. (5), indicating gas-particle mass transfer, where…”

“…Compared with traditional hydrogen production from coal which involved several steps including gasification, water-gas shift, and CO 2 fixation in separate reactors, this new method integrated the above processes into one reactor, and greatly simplified the overall process. By adding calcium-based absorbents into the coal gasifier, coal conversion reaches 90 % and the concentration of H 2 more than 80 vol.-% in a batch microreactor at 873-973 K and 12-105 MPa [1][2][3]. Recently, continuous coal gasification experiments at a bench scale were conducted with CaO as the absorbent in the range of 0.1-6.0 MPa and 923 K [4,5], the H 2 concentration reached 77 vol.-%, and only 2 vol.-% CO 2 and not more than 1 vol.-% CO were detected.…”