江苏油田砂岩酸压增注技术研究与应用

"Sandstone Acid-fracturing for Increasing Injection" Technology in Jiangsu Oilfield

江苏SN油田高压注水井达不到配注要求,采用常规酸化增注措施无效的情况下,在砂岩储层进行酸压增注,获得成功。分析了砂岩储层一般情况下不能进行酸压的原因,提出了砂岩储层要获得成功酸压增注需具备的条件,并在室内对油田岩样进行了酸蚀裂缝导流能力试验。结果表明,酸蚀后岩样不但结构完整,而且获得了良好的导流能力,认为在砂岩油藏进行酸压是可行的。现场应用新型酸化液非活性硝酸粉末液复合酸进行了7口井砂岩酸压增注施工,取得了良好的降压增注效果。

The use of acid-fracturing for increasing injection proved successful in the block SN in Jiangsu oilfield after the application of high pressure injection and the routine acid injection-increasing was failed in that block.The reason why sandstone reservoirs cannot be acid-fractured was analyzed and the prerequisites for successful acid-fracturing for increasing injection were presented.Laboratory studies were conducted on the flow conductivity of the acid-eroded fractures,which showed that sandstones maintained intact rock structure while having good flow conductivity after acid-erosion.This implied that the acid-fracturing for increasing injection shall apply in field operation in sandstone reservoirs.The technology was used in seven wells with sandstone reservoirs and good injection was obtained.