中、高煤阶煤岩压裂裂缝导流能力实验研究

运用FCES-100长期裂缝导流仪，测试了中、高煤阶煤岩水力裂缝的长期导流能力，并考虑了煤粉对导流能力的伤害，提出了简易测试煤层复杂裂缝导流能力的方法。通过室内实验测试分析认为，不同煤阶煤岩由于力学性质等的不同，在相同条件下其导流能力有明显的差异，煤层水力压裂施工设计中应考虑煤阶对裂缝导流能力的影响；支撑剂嵌入对煤岩裂缝导流能力伤害严重，适当增加铺砂浓度、加大支撑剂粒径、压裂液中加入分散剂可以降低支撑剂嵌入和煤粉的伤害；裂缝形态对煤岩的导流能力也存在影响，多条裂缝与单一裂缝的导流能力不同。

Experimental evaluation of conductivity of fracturing in medium and high rank coal beds

The long term conductivity of hydraulic fractures in medium rank and high rank coal bed was tesed by using of FCES 100 fracture long term flow conductometer,considering the damage of coal powder on fracture conductivity,and put forward a simple method for testing complex fracture conductivity in coal beds.According to the analysis on laboratory experiment,for different ranks of coal beds,conductivity at the same conditions varies sharply due to the differences of mechanical properties.Therefore,the influence of coal ranks on fracture conductivity shall be taken into consideration in coal bed hydraulic fracturing design.Proppant embedment can pose a great damage on fracture conductivity of coal bed.However,increasing the sand concentration,enlarging the proppant diameter and adding dispersant into the fracturing fluid appropriately can decrease the embedment of proppant and lower the damage of coal powder.Fracture morphology also plays an important role on the conductivity of fractures and conductivity of multiple fractures is different from that of single fracture.