IMPROVEMENT OF METHANE STORAGE CAPACITY IN ACTIVATED CARBON BED WITH BIDISPERSE PACKING

Abstract This study presents a numerical investigation of the dynamics of methane adsorption in granular activated carbon beds with bidisperse packing in order to reduce the void spaces between the adsorbent particles and to improve the storage capacity in adsorbed natural gas vessels. Two distinct particle sizes (d and D) were used for the packing of the bidisperse bed, and the following particle size ratios were investigated: δ = d/D = 1 (monodisperse bed), 1/5, 1/10, 1/15, and 1/20. Compared with the monodisperse bed condition, the results obtained showed that bidisperse packing increases bed density by about 30% and methane storage capacity by up to 20%. The results also showed that the charging time could be optimized by increasing the pressure drop applied to the bed and that the storage capacity can be increased by cooling the admitted gas in the vessel.

摘要 本研究针对双粒径填充（bidisperse packing）颗粒活性炭床的甲烷吸附动力学开展数值研究，旨在降低吸附剂颗粒间的空隙体积，提升吸附天然气（Adsorbed Natural Gas）存储容器的储气量。本研究采用两种不同粒径（d与D）构建双粒径填充床，并探究了粒径比δ = d/D分别为1（单粒径填充床）、1/5、1/10、1/15及1/20的工况。与单粒径填充床工况相比，研究结果表明：双粒径填充可使床层密度提升约30%，甲烷储气量最高提升20%。此外，结果还显示通过增大床层压降可优化充气时长，而冷却容器内通入的气体则可进一步提升储气量。