深部煤层封存CO_2的地质主控因素探讨

目前世界上多数国家都以CO2捕获和封存作为CO2减排的有效措施之一。向深部不可采煤层中封存CO2能一举两得,既可实现CO2减排的目的,又能置换出煤层甲烷气体。从实验室研究角度出发,分析了煤级、温度、压力、水分及氮气对煤吸附CH4、CO2的影响,并结合煤层气开发选区评价方法,探讨了影响煤层封存CO2的地质主控因素,认为煤种、煤厚、煤层埋深、渗透率是主要控制因素,而地质构造、水文地质、甲烷气含量等为次一级控制因素。综合分析认为,我国煤层封存CO2的潜力很大,而华北地区是深部煤层封存CO2的首选地区。

A Discussion on Main Geologic Controlling Factors of CO_2 Sequestration in Deep Coal Seams

The CO2 capture and storage（CCS） as one of effective measures in carbon emission reduction is widely adopted in major countries.In which,CO2 sequestration in deep unrecoverable coal seams can serve two ends： reduction of carbon emission and substitution of CBM from such coal seams.Based on laboratory studies,analyzed impacts from coal rank,temperature,pressure,moisture and nitrogen on adsorption of CH4 and CO2 by coal,combined with CBM exploitation area selection assessment,discussed main geologic controlling factors of CO2 sequestration in coal seams,and finally reckoned that they are coal rank,coal thickness,buried depth and permeability,while geological structure,hydrogeology and methane content are subordinate.The comprehensive analysis has considered that the potential of CO2 sequestration in deep coal seams in the country is quite large,while the North China area is the preferred.