TY  - JOUR
A1  - Otto, Christopher
A1  - Kempka, Thomas
T1  - Synthesis gas composition prediction for underground coal gasification using a thermochemical equilibrium modeling approach
JF  - Energies
N2  - Underground coal gasification (UCG) is an in situ conversion technique that enables the production of high-calorific synthesis gas from resources that are economically not minable by conventional methods. A broad range of end-use options is available for the synthesis gas, including fuels and chemical feedstock production. Furthermore, UCG also offers a high potential for integration with Carbon Capture and Storage (CCS) to mitigate greenhouse gas emissions. In the present study, a stoichiometric equilibrium model, based on minimization of the Gibbs function has been used to estimate the equilibrium composition of the synthesis gas. Thereto, we further developed and applied a proven thermodynamic equilibrium model to simulate the relevant thermochemical coal conversion processes (pyrolysis and gasification). Our modeling approach has been validated against thermodynamic models, laboratory gasification experiments and UCG field trial data reported in the literature. The synthesis gas compositions have been found to be in good agreement under a wide range of different operating conditions. Consequently, the presented modeling approach enables an efficient quantification of synthesis gas quality resulting from UCG, considering varying coal and oxidizer compositions at deposit-specific pressures and temperatures.
KW  - underground coal gasification
KW  - Cantera
KW  - thermodynamic equilibrium
KW  - composition
KW  - synthesis gas
KW  - oxidizer
Y1  - 2020
U6  - https://doi.org/10.3390/en13051171
SN  - 1996-1073
VL  - 13
IS  - 5
PB  - MDPI
CY  - Basel
ER  -