静止悬垂水滴形成甲烷水合物的生长动力学  

Kinetics of Methane Hydrate Formation from Static Pendant Water Droplets

作　　者：钟栋梁[1] 杨晨[1] 刘道平[2] 

机构地区：[1]重庆大学动力工程学院,重庆400030 [2]上海理工大学能源与动力工程学院,上海200093

出　　处：《化学反应工程与工艺》2010年第1期52-57,共6页Chemical Reaction Engineering and Technology

基　　金：国家自然科学基金项目(50276038)

摘　　要：在273.35～277.15 K,4.86～6.65 MPa条件下开展了静止悬垂水滴形成甲烷水合物的可视化实验,提出了气-液平衡时水滴表面CH_4气体溶解度的计算方法以及描述水滴表面水合物膜生长的动力学模型,预测了悬垂水滴形成甲烷水合物的生长时间。结果表明,悬垂水滴转化为水合物颗粒的时间随着系统压力的升高而缩短,随着系统温度的降低而减小。水滴越小,反应时间越短。水滴尺寸和CH_4的扩散阻力对水合反应的影响比系统压力、温度的影响大得多。CH_4在水合物膜中的扩散阻力是影响悬垂水滴转化为水合物的主要因素,进行喷雾反应釜设计时,须尽量消除扩散阻力的影响,加快气体水合物的合成速率。Experiments of forming methane hydrate at the surface of static pendant water droplet were carried out at 273.35-277.15 K and 4.86-6.65 MPa, and visually observed. A computational method was proposed to calculate the amount of methane dissolved into the water droplet at vaporliquid two phase equilibrium state. A kinetic model was proposed to describe the growth of methane hydrate film at the surface of water droplet and the growth time of hydrate film on the surface of pendant water droplet was predicted. The results indicated that the growth of hydrate film was accelerated with the elevation of system pressure, but decreased with the increase of system temperature. The smaller the water droplet was, the faster the growth of hydrate film. Compared to system pressure and temperature, the effect of droplet size and diffusion barrier on hydrate formation were much greater. The diffusion harrier in hydrate film was a major factor affecting the conversion of suspended water droplet into gas hydrate. The influence of diffusion barrier should be eliminated in designing the water spray reactor, so as to increase the formation rate of gas hydrate.

关 键 词：气体水合物 水滴 喷雾反应器 气体溶解度 扩散 

分 类 号：TE8[石油与天然气工程—油气储运工程]