The feasibility of CO2 emission reduction by adsorptive storage on Polish hard coals in the Upper Silesia Coal Basin: An experimental and modeling study of equilibrium, kinetics and thermodynamics

Elżbieta Gabruś; Karolina Wojtacha-Rychter; Tomasz Aleksandrzak; Adam Smoliński; Magdalena Król

doi:10.1016/j.scitotenv.2021.149064

The feasibility of CO₂ emission reduction by adsorptive storage on Polish hard coals in the Upper Silesia Coal Basin: An experimental and modeling study of equilibrium, kinetics and thermodynamics

Sci Total Environ. 2021 Nov 20:796:149064. doi: 10.1016/j.scitotenv.2021.149064. Epub 2021 Jul 14.

Authors

Elżbieta Gabruś¹, Karolina Wojtacha-Rychter², Tomasz Aleksandrzak³, Adam Smoliński⁴, Magdalena Król⁵

Affiliations

¹ West Pomeranian University of Technology, Szczecin, Faculty of Chemical Technology and Engineering, Department of Chemical and Process Engineering, al. Piastów 42, 70-065 Szczecin, Poland. Electronic address: Elzbieta.Gabrus@zut.edu.pl.
² Central Mining Institute, Department of Mining Aerology, Pl. Gwarków 1, 40-166 Katowice, Poland.
³ West Pomeranian University of Technology, Szczecin, Faculty of Chemical Technology and Engineering, Department of Chemical and Process Engineering, al. Piastów 42, 70-065 Szczecin, Poland.
⁴ Central Mining Institute, Pl. Gwarków 1, 40-166 Katowice, Poland.
⁵ AGH University of Science and Technology, Department of Silicate Chemistry, Mickiewicza 30, 30-059 Kraków, Poland.

PMID: 34328898
DOI: 10.1016/j.scitotenv.2021.149064

Abstract

Carbon dioxide storage in unmineable coal seams is advantageous in the highly industrialized areas, such as the Upper Silesia Coal Basin (USCB), Poland, where heavy industry constitutes the source of huge CO₂ emissions and coal mines will be closed in the future, due to unprofitability. The paper presents the results of experimental and theoretical research of CO₂ capture on medium rank C and B bituminous coals coming from three mines located in the USCB. The porous texture of the investigated adsorbents was analyzed using SEM images and the N₂ and CO₂ isotherms at -196 °C and 0 °C, respectively. Qualitative studies using DRIFT spectroscopy showed that band intensity attributed to the functional groups of coals changed after CO₂ adsorption. The analyses encompassed the equilibrium, kinetics and thermodynamics of CO₂ adsorption on coals at 25, 50 and 75 °C (up to 2000 kPa). The adsorption isotherms were obtained by the static gravimetric method and described by means of the Langmuir, Freundlich, Dubinin-Radushkevich and Dubinin-Astakhov models. The highest CO₂ uptakes were obtained for medium rank C bituminous coals at 25 °C; the values were 1.600 mol/kg and 1.274 mol/kg. The adsorption kinetics was better characterized by the Avrami fractional-order model rather than by the pseudo-first and pseudo-second order models. The results reveal that the adsorption process is the fastest for medium rank C bituminous coals. The isosteric heats of adsorption were calculated in the following two ways: based on the multi-temperature Toth isotherm and the Clausius-Clapeyron equations. Depending on degree of coal metamorphism, the heat of adsorption ranged from 18 to 26 kJ/mol. The estimated maximum temperature increase due to heat accumulation in the insulated coalbed during CO₂ adsorption was 6 °C and did not reach the self-ignition temperature in any of the tested adsorption systems.

Keywords: Adsorption isotherms and kinetics; Carbon dioxide capture; Geological storage; Hard coal; Thermodynamic studies.

MeSH terms

Adsorption
Carbon Dioxide*
Coal*
Feasibility Studies
Kinetics
Poland
Thermodynamics

Substances

Coal
Carbon Dioxide