川中异常高应力裂缝性气藏加砂压裂现场试验研究

Research of Sand Fracturing Field Experiences on the Fracture-type Gas Reservoir with Abnormal High Stress in Central Sichuan

四川川中须家河须四气藏施工井深2400～2800m,地层温度70℃～85℃,具有基质低孔、低渗、地应力高、天然裂缝发育等特点。以往压裂规模小、易砂堵、单井难以获得工业性气流。针对该气藏特征及以往压裂技术存在的问题开展现场试验研究,现场4次试验,施工有效率100%。最大加砂量达到78m3,最大砂浓度达到940kg/m3。该项试验提高了气藏压裂技术水平,增产效果显著,如西64井压前产量为0.31×104m3/d,压后产量达到2.5×104m3/d。

The depth of Xusi gas reservoir construction well of Xujia river reservoir of Central Sichuan is about 2400~2800m, with formation temperature of 70℃~85℃. The gas reservoir in this area has characteristics such as lower matrix porosity, low permeability, and high stress and so on. The former fracturing technique did not get commercial natural gas production. To analyze the characteristics of that reservoir and solve the open question of former fracturing technique, field test is developed, the time of field test is 4, and each construction efficacy is 100%. The maximum sand capacity is 78 m3, and the maximum sand consistence is 940 kg/m3, the fracturing technique is improved and the effect is remarkable. The former output of LUSI64# well was 0.31×104m3/d, but the output is 2.5×104m3/d after fracturing technique is applied, the effect is remarkable.