通道压裂裂缝导流能力影响因素研究

Study on Infleuence Factors of Channel Fracturing Fracture Seepage Ability

为了研究高速通道压裂裂缝内的支撑规律及裂缝导流能力,利用FCES-100导流仪对砂岩岩板进行室内导流能力测试。对比通道压裂铺砂与连续铺砂裂缝导游能力的差异,分析了纤维浓度、铺砂方式和支撑剂类型对通道压裂裂缝导流能力的影响。实验结果表明:低闭合压力下,通道压裂裂缝比连续铺砂裂缝导流能力大,随着闭合压力增加,通道压裂裂缝导流能力下降速度更快;纤维缠绕支撑剂形成网状结构,增加支撑剂团的稳定性,压裂液中最佳纤维质量分数为0.5%;支撑剂团的面积变化系数越大,通道压裂裂缝导流能力越低;支撑剂团块总面积大有利于增大通道压裂裂缝承压能力,但总面积过大裂缝导流能力反而会降低;对比通道压裂中3种支撑剂,覆膜砂的效果最好,其次是陶粒,石英砂效果最差。

In order to study the proppant support law and the fracture seepage ability of channel fracturing,the seepage ability of fracture was tested using FCES-100 instrument. The fracture seepage abilities of channel fracturing sand laying and cotinuous sand laying are are comparied,and the effects of fiber concentration,proppant laying form and proppant type on the fracture seepage ability are analyzed. It is shown that under low clousure stress pressure,the seepage ability of channel fracturing fracture is greater and it decreases more quick with the clousure pressure increasing than that of continuous proppant laying fracture; the network structure formed by fiber winding proppant increases the stability of proppant groups,the optimal fiber mass fraction is 0. 5%; the greater the area variation of the proppant groups,the lower the the seepage ability of channel fracturing fracture; the large total area of the proppant groups is favourable to the increase of the pressure bearing capacity of channel fracturing fracture,but too large total area will reduce the seepage ability of channel fracturing fracture; of three types of proppant,the effect of coated sand is the best,the effect of ceramsite is secondary,and the effect of quartz sand is the worst. The experimental results have certain guiding significance to laboratory research and field construction of channel fracturing.