水对采空区遗煤吸附电厂烟气影响的理论计算

发布时间：2018-06-17 13:57

本文选题：电厂烟气 + 煤　；参考：《燃料化学学报》2017年09期

【摘要】：为研究电厂烟气注入采空区时,煤中含水率和烟气中水分对于封存温室气体CO_2和抑制煤自燃的影响,建立干煤和湿煤结构模型,采用巨正则系综蒙特卡洛方法,计算了不同水分含量的烟气组分CO_2/O_2/N2/H_2O在干煤以及不同含水率的湿煤中的吸附行为。结果表明,烟气中CO_2竞争性最强吸附量最大,O_2的物理吸附量极小,烟气中H_2O含量不影响CO_2、N2和O_2的吸附量,可不进行干燥处理直接将电厂烟气注入采空区。随着煤中含水率增加,水分占据孔隙空间,范德华作用减弱,H_2O-H_2O之间的氢键作用增强且提供了额外吸附位。H_2O的等量吸附热升高,吸附位移向吸附作用更强的低相互作用能区域,吸附大量水形成水团簇,与CO_2竞争吸附位,并且占据吸附空间抑制CO_2、O_2、N2的吸附,使其吸附量降低50%以上,因此,注入烟气时应充分考虑采空区煤体的含水率问题。
[Abstract]:In order to study the influence of moisture content in coal and flue gas on the storage of greenhouse gas COS2 and the suppression of spontaneous combustion of coal, a structural model of dry and wet coal was established, and the giant canonical ensemble Monte Carlo method was used to study the effects of water content in coal and flue gas on coal spontaneous combustion when flue gas was injected into goaf in power plant. The adsorption behavior of CO _ 2 / O _ 2 / H _ 2O in dry coal and wet coal with different moisture content was calculated. The results show that the maximum competitive adsorption capacity of CO-2 in flue gas is very small, and the content of H _ 2O in flue gas does not affect the adsorption capacity of CO _ 2N _ 2 and O _ 2, so the flue gas can be injected directly into the goaf without drying treatment. With the increase of water content in coal and water occupying pore space, van der Waals' interaction weakens and the hydrogen bond between H2O-H2O increases and provides an additional adsorption site. The adsorption displacement increases to a low interaction energy region with stronger adsorption. A large amount of water is adsorbed to form a water cluster, which competes with COSP _ 2 and occupies an adsorption space to suppress the adsorption of CO2O _ 2N _ 2 and reduce the adsorption capacity by more than 50%. Therefore, the moisture content of coal in goaf should be fully considered when injecting smoke.
【作者单位】：辽宁工程技术大学安全科学与工程学院;山西焦煤集团有限责任公司;辽宁工程技术大学安全工程技术研究院;
【基金】：国家自然科学基金(51174108)资助~~
【分类号】：X773

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