煤层气水平井煤粉产生机理及控制措施

Production mechanism and control measures of coal powder in coalbed methane horizontal well

为了揭示煤层气水平井煤粉产生机理,采用理论分析和现场实验的方法,分析了煤层气水平井产出煤粉的质量分数及颗粒粒径变化规律,提出了使用防砂尾管结合油套环空注水稀释煤粉质量分数预防卡泵的措施。研究结果表明:煤层气水平井产出煤粉颗粒粒径呈阶段变化特征,煤粉质量分数超标是导致卡泵停机的主要原因,使用防砂尾管结合井底注水稀释煤粉质量分数措施能有效延长煤层气排采井检泵周期。

To reveal the production mechanism of coal powder in coalbed methane horizontal wells,the coal powder concentrations and particle size variations in coalbed methane horizontal wells are analyzed by combining theoretical analyses with field experiment.Also,the measures of using sand control liner combination of water injection in tube-casing annular space to dilute coal powder concentration is proposed for preventing pump stuck.The study results show that the stepped changes characteristic of coal powder particle size,and higher coal powder concentration than standard are major causes of pump stuck.The field application results demonstrate that the pump inspection cycle in a coalbed methane drainage wells is effectively extended by the measure proposed in this study.