煤粉产出对高煤阶煤层气井产能的影响及其控制

从实际资料入手，应用扫描电镜，测井解释等方法，系统研究了煤粉产出的机理，分析了煤粉产出对煤层气井产能的影响，并积极探索控制煤粉产出的方法.研究认为:煤粉产生的主要原因包括地应力变化导致煤岩基质破裂、钻井工具研磨及压裂支撑剂的打磨，并与煤岩性质密切相关；软煤层是煤粉的主要来源，其黏土矿物成分高达16.75%~22.53%，电阻率比原生结构煤低一个数量级，基本在1 kΩ·m以下，而自然伽马、声波时差明显偏高；水平钻井和压裂射孔避开软煤层段施工与使用高圆度压裂支撑剂等是降低煤粉产出的有效方法，应用防砂泵以及科学的排采技术可以有效降低煤粉产出对煤层气产能的负面影响.

Destructive influences and effectively treatments of coal powder to high rank coalbed methane production

Based on the actual information, and used the scanning electron microscope and log interpretation, the form mechanism and destructive influences of coal powder were analyzed and the control methods were researched. It proves that the contributing factors of coal powder, intently associated with the property and composition are very complex, including the coal matrix collapsing affected by ground stress change, the drilling bit abrasion and the fracture proppant grinding. The soft coal, main origin of coal powder, 16.75%~22.53% clay mineral, is distinguished with the lower electric resistivity and higher combination Gamma ray neutron laterolog and acoustic travel time, compared with the primary structure coal, which electric resistivity is less than 1 kΩ·m. It is proposed that optimizing construction interval of horizontal drilling and fracture and using the high circularity fracture proppant can effectively decrease the coal powder volume. The sand prevention pump and scientific gas production technology, effectively decreasing the destructive influences of coal powder are essential and are proposed.