煤层气井井筒煤粉运移规律研究  

Coal dust migration in the wellbore of coalbed methane

作　　者：牛骏[1] 石在虹[1] 柯文奇 NIU Jun;SHI Zai-hong;KE Wen-qi(Petroleum Exploration and Production Research Institute of SINOPEC,Beijing 200240,China)

机构地区：[1]中国石油化工股份有限公司石油勘探开发研究院,北京100083

出　　处：《水动力学研究与进展（A辑）》2020年第3期385-390,共6页Chinese Journal of Hydrodynamics

摘　　要：煤层气井排采过程中由于储层析出煤粉,现场经常遇到煤粉沉降堵塞井筒及煤粉卡泵问题,急需针对井筒内煤粉运移的分析预测方法。该研究建立了井筒内垂向和径向煤粉运移数学模型及求解方法,在此基础上分析了煤层气井井筒流体煤粉携出能力及煤粉径向浓度分布规律。研究结果表明,排水速度越快井筒流体携出煤粉能力越强,对于直径200μm以内的煤粉,排水速度超过3 m^3/d(3.48×10^-5m^3/s)便可将煤粉全部携出。煤粉呈现向井筒中线聚集现象,距离井筒中线越近煤粉浓度越高,并且排水速度越快煤粉聚集现象越显著,当排水速度达到5 m^3/d(5.79×10^-5m^3/s)时井筒中线煤粉浓度是壁面附近的10倍。相同排水速度下,颗粒粒径增大会使得煤粉在井筒中线附近浓度略微降低。The prediction of coal dust migration in the CBM wellbore is of great importance,as the coal dust may cause tubing blockage and pump stuck leading to the reduction of production efficiency.In this paper,the models for analyzing the vertical and radial migration of coal dust in the wellbore are built.The results show that the dust carry-out ability of the wellbore flow increases with the increase of the water production rate.For the coal dusts with diameter smaller than 200μm,the wellbore flow with water production rate larger than 3 m3/d(3.48×10^-5 m^3/s)is able to carry them all out.The coal dust displays non-uniform radial distribution,and the concentration of the coal dust gets lower from the center of the wellbore to the side wall.When the water production rate reaches 5 m^3/d(5.79×10^-5 m^3/s),the dust concentration in the center is 10 times that near the side wall.A higher water production rate can further increase the central coal dust concentration.With fixed water production rate,the increase of coal dust size corresponds to lower concentration around the center of the wellbore.

关 键 词：煤层气 井筒流动 煤粉沉降 浓度分布 

分 类 号：TQ547.7[化学工程—煤化学工程]