单层铺砂条件下煤岩裂缝导流能力实验研究

Experimental study on the flow capacity of the fracturing fractures with monolayer proppant in coal beds

为了深入研究煤岩压裂裂缝导流能力,运用FCES-100裂缝导流仪测试了低铺砂浓度尤其是单层铺砂条件下煤岩裂缝导流能力,并考虑了嵌入作用、天然裂缝等因素的影响.实验结果表明:在较低闭合压力下单层铺砂能够支持煤岩裂缝,获得理想的导流能力;不同煤岩由于力学性质的不同,单层铺砂导流能力存在较为明显的差异,在高闭合压力下支撑剂嵌入对质软的煤岩裂缝导流能力伤害严重;时间和实验煤岩板上存在的天然裂缝对单层铺砂煤岩裂缝导流能力存在影响.

The flow capacity of hydraulic fracturing fractures with low concentration proppant specifically monolayer proppant in coal beds is measured by using FCES-100 fracture flow capacity instrument,and on which the effects of proppant embedment and natural fractures are considered.The experimental results show that under lower closure pressure,monolayer proppant can support the hydraulic fracturing fractures in coal beds and good flow capacity of fracturing fractures can be obtained.There is difference in flow capacity of fracturing fractures in the coal beds of different mechanical properties.Under higher closure pressure,the flow capacity of fracturing fractures will be damaged by the proppant embedding into soft coal rock.Besides,time and natural fractures will produce influence on the flow capacity of fracturing fractures with monolayer proppant.