驱动力对煤介质中CO_(2)水合物生长动力学的影响

Effect of driving force on kinetics of CO_(2) hydrategrowth in coal media

为探究不同驱动力对煤介质中CO_(2)动力学的影响,开展了3种驱动力条件下煤介质中CO_(2)水合物生长动力学实验,获取了CO_(2)水合物生成过程中动力学参数。结果表明:相同粒径体系生成水合物的过程中,3 MPa驱动力的CO_(2)气体消耗量约为2.5 MPa、2 MPa驱动力CO_(2)气体消耗量的1.14、1.34倍;不同粒径体系驱动力增加,体系内气体分子运动加快,气体分子与液面水分子碰撞的次数也会随之增高,CO_(2)水合物结晶成核的机会也随之增加,CO_(2)水合物气体消耗量、生长速率随之加快。在0.150~0.850 mm粒径范围内随着煤介质粒径增大,CO_(2)水合物生长速率逐渐提高;利用线性拟合获取了CO_(2)水合物平均生长速率与驱动力关系式,为预测CO_(2)水合物的平均生长速率提供参考。

This paper intends to investigate the effect of different driving forces on CO_(2)dynamics in coal media.The study conducts a experimental research on the growth kinetics of CO_(2)hydrate in coal media under three driving forces to obtain the kinetic parameters of CO_(2)hydrate in synthesis process.The results show that in the process of hydrate generation in the same particle size system,the CO_(2)gas consumption of 3 MPa driving force is about 1.14 times and 1.34 times of that of 2.5 MPa and 2 MPa driving force.The increase of driving force in different particle size systems accelerates the movement of gas molecules in the system,together with the increase of collisions of the gas molecules with water molecules at the liquid surface,and it follows the increase of the CO_(2)hydrate crystal nucleation,and the quick speed of the CO_(2)hydrate gas consumption and the growth rate.Between the particle size of 0.150-0.850 mm,the growth rate of CO_(2)hydrate increases gradually with the enlargement of the partical size.The relation between the average growth rate of CO_(2)hydrate and the driving force obtained by linear fitting provides a reference for predicting the average growth rate of CO_(2)hydrate.