中文摘要：

为了合理控制煤层气井产出煤粉,以沁水盆地南部高阶煤为研究对象,通过不同有效应力和水注入速率下压裂裂缝渗透率的测定,探讨了煤粉运移对压裂裂缝渗透率的影响。结果表明,压裂裂缝渗透率随有效应力的增加先减小后增大;有效应力≤4 MPa时,随有效应力增大,煤粉淤堵加重,压裂裂缝渗透率迅速降低;有效应力〉4 MPa时,煤由弹性形变转变为塑性形变,裂缝渗透率增大。铺单一粒径压裂砂的情况下,水注入速率≤20 mL/min时,水携带煤粉的能力较弱,煤粉淤堵严重,裂缝渗透率迅速降低;水注入速率〉20 mL/min时,高速水流缓解了煤粉淤堵,渗透率降幅变缓。混合铺砂时,压裂砂打磨裂缝壁面,造成压裂裂缝渗透率升高。

英文摘要：

In order to reasonably control coal fines output of coalbed methane（CBM） well, taking high-rank coal in southern Qinshui basin as reseach object, permeability of fracturing fractures under different effective stress and different rate of water injection was measured. Based on the permeability, influence of coal fines output on permeability of fracturing fractures was discussed. The results show that with the increase of effective stress, permeability of fracturing fractures increases firstly and then decreases. When effective stress is equal to or less than 4 MPa, with the increase of effective stress, permeability of fracturing fractures declines rapidly because of the clogging of coal fines. When effective stress is more than 4 MPa, plastic deformation of coal matrix occurs, which causes the increase of permeability. When there is single grain size sand in fracturing fractures and the rate of water injection is equal to or less than 20 mL/min, the permeability declines rapidly because of the low water carrying capacity of coal fines and the serious clogging of coal fines. When rate of water injection is more than 20 mL/min, high velocity flow alleviates clogging of coal fines and the permeability has slowed down. When mixed sanding is in fracturing fractures,fracturing sand polishes the wall of fracturing fracture and causes the increase of permeability.