深调浅堵技术在蒸汽吞吐稠油井中的应用

报道了适用于发生套管外窜槽的蒸汽吞吐稠油井的深调浅堵技术,包括深调和浅堵堵剂、封堵技术原理及施工工艺。首先对目的油层实施暂堵保护,介绍了可供选择的4种暂堵剂及不同井况下使用的4种暂堵方法。此后注入深调堵剂,其中处于溶液状态的部分水解聚丙烯酰胺、溶胀后的体膨颗粒中的聚丙烯酰胺依次分别与甲醛、间苯二酚、乌洛托品分解出的甲醛反应,与增强剂黏土一起形成凝胶。最后注入浅堵堵剂,其中的不饱和聚酯树脂在对甲苯磺酸催化下发生聚合,在偶联剂作用下与地层砂粒及堵剂的无机成分形成牢固的耐高温封堵物。在注入蒸汽时,深部堵剂凝胶破胶、破碎,沿大孔道运移,起深部调剖和蒸汽转向作用。此技术自2004年起已在辽河油田多个稠油区块9口蒸汽吞吐井成功使用,增油显著。图3参3。

An Indepth Profiling/Shallow Water Shutoff Technology for Steam Huffing-Puffing Heavy Oil Wells

The titled technology is developed for sealing out casing interlayer channellings and reducing disproportionate reservoir permeability in steam huffing-puffing heavy oil wells.The plugging agents used,the principles of indepth profiling and water shutoff in near bore zones,and the processes and technologies are presented.The aimed reservoir layers must be preliminarily well protected with one of 4 available temperarily shielding/plugging agents by using one of 4 means depending upon the well conditions.the indepthprofiling agent is then injected and forms in-situ a clay reinforced gel through crosslinking of PAM in swelled particulated material and HPAM in solution by formaldehyde,introduced as such and as decomposition product of urotropine,and resorcine.The shallow water shutoff agent is emplaced in near bore zones,where unsaturated polyester resin polymerization occurs at the presence of catalyst p-toluenesulfonic acid and the polymerisate bonds formation sand and inorganic particles introduced together to give strong thermoresistant blockages.With scouring steam stream injected the gelled indepth profiling agent breaks down and transports along big passages,modifying relative permeability and diverting the steam stream to less permeable zones.This technology has been successfully used in 9 steam huffing-puffing wells at several heavy crude reservoirs in Liaohe oil fields since 2004,giving a notable gain in oil output.