煤层气有杆泵井排采煤粉产出规律表征与分析

为探索煤层气有杆泵井排采煤粉产出的实际沉降速度和临界排液量,建立了有杆泵井井筒煤粉运移动态实验平台,模拟了不同煤粉粒度、不同排液速度井筒煤粉动态运移规律。结合球形颗粒沉降末速理论公式,建立了有杆泵井排采不同煤粉粒度实际沉降速度和临界排液量计算模型。研究表明,实际有杆泵排采实际沉降速度和临界排液量与井液密度、井筒内流体流态、煤粉粒径、煤粉密度及井筒流体流速有关,且随着煤粉粒度的减小实际沉降速度和临界排液量降低,并计算出不同煤粉粒度的排采临界排液量。有杆泵井排采时实际沉降速度和临界排液量可为现场防煤粉控制、排采设备优化等方案设计提供依据。

Characterization and Analysis of Powered Coal Entrainment Law in Drainage Period by Rod Pump for Coal-Bed Methane Wells

In order to study the critical flowrate and the real terminal velocity of powdered coal entrainment in drainage period by rod pump for coal-bed methane wells, the experiment platform of powdered coal migration in rod pump wellbore was built and the experiment of powdered coal migration law under the condition of different powdered coal size and drainage velocity was simulated. Take consider of spherical particle terminal velocity, the calculation method of the critical flowrate of different powdered coal size in drainage period by rod pump. The study shows that, the real terminal velocity and critical flowrate were concerned with fluid density, fluids flow state, powdered coal size, powdered coal density and fluid velocity. With decreasing of powdered coal size, the critical flowrate and the real terminal velocity decrease. The critical flowrate of powdered coal entrainment in drainage period by rod pump under the condition of different powdered coal size was calculated. This study has a great guiding significance on equipment optimization and powdered coal prevention design.