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.
Central Mining Institute, Department of Mining Aerology, Pl. Gwarków 1, 40-166 Katowice, Poland.
Sci Total Environ. 2021 Nov 20;796:149064. doi: 10.1016/j.scitotenv.2021.149064. Epub 2021 Jul 14.
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 CO emissions and coal mines will be closed in the future, due to unprofitability. The paper presents the results of experimental and theoretical research of CO 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 N and CO 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 CO adsorption. The analyses encompassed the equilibrium, kinetics and thermodynamics of CO 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 CO 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 CO adsorption was 6 °C and did not reach the self-ignition temperature in any of the tested adsorption systems.
在高度工业化的地区，如波兰上西里西亚煤盆地（USCB），无法开采的煤层中的二氧化碳储存具有优势，因为重工业是大量 CO 排放的来源，而且由于无利可图，未来煤矿将关闭。本文介绍了从中西里西亚三个煤矿开采的中阶 C 和 B 烟煤对 CO 捕获的实验和理论研究结果。使用 SEM 图像和 N 和 CO 分别在-196°C 和 0°C 下的等温线分析了吸附剂的多孔结构。使用 DRIFT 光谱的定性研究表明，CO 吸附后，归因于煤官能团的带强度发生了变化。分析包括 25、50 和 75°C（高达 2000 kPa）下 CO 在煤上的吸附平衡、动力学和热力学。通过静态重量法获得吸附等温线，并通过 Langmuir、Freundlich、Dubinin-Radushkevich 和 Dubinin-Astakhov 模型进行描述。在 25°C 下，中阶 C 烟煤获得了最高的 CO 吸收量；值分别为 1.600 mol/kg 和 1.274 mol/kg。吸附动力学更适合用 Avrami 分数阶模型而不是伪一阶和伪二阶模型来描述。结果表明，中阶 C 烟煤的吸附过程最快。通过多温度 Toth 等温线和 Clausius-Clapeyron 方程，以两种方式计算了吸附的等焓。根据煤变质程度，吸附热范围从 18 到 26 kJ/mol。由于 CO 吸附过程中隔热煤层中热量的积累，估计最大温度升高为 6°C，在任何测试的吸附系统中均未达到自燃温度。
