聚合物驱后地层残留聚合物絮凝再利用技术研究

河南双河油田北断块Ⅱ4.5注聚结束时大量聚合物残留在地层中，聚合物的浓度分布在200—600mg／L之间。聚合物驱后恢复水驱，注入水沿高渗透层窜流，含水率迅速上升。针对双河油田聚合物驱之后出现的实际问题，研究了一种可以进一步提高采收率的采油技术——聚合物絮凝再利用技术。该技术是利用地层残留低浓度聚合物对絮凝荆的桥接吸附作用形成絮凝体封堵高渗透层，达到深部调剖、提高水驱采收率的目的。通过室内实验，筛选出的最佳絮凝剂为3wt％稳定化钠土（YG340-1），且絮凝荆越旱注入对聚合物再利用效果越好。该项技术已在双河油田进行了矿场试验，并取得了较好的效果，具有广阔的应用前景。

Research on Technology of Formation Polymer Flocculation Residue Recycle after Polymer Flooding

A large amount of polymer residue is left over in the formation after polymer flooding in the north fault block II4,5 in Shuanghe Oil Field in Hehan.The polymer density distribution range is 200-600mg/L.Water flooding is resumed after polymer flooding and the injected water flows across the high permeability layers making the water cut increase rapidly.To solve the real problem after polymer flooding in Shuanghe Oil Field,a production technique that can further improve the recovery factor is studied,that is,polymer flocculation recycle technique.This technique can realize deep profile adjustment and water flooding recovery factor enhancement by plugging the high permeability layers with the floc units generated from the bridging and adsorption of the formation low density polymer residue on the flocculant.Through the in-house experiments,3wt% stabilized natrium soil(YG340-1) is screened out as the best flocculant.The experiments also indicate that the earlier the flocculant is injected,the better the polymer recycle effect is.This technique has been applied in the field test in Shuanghe Oil Field and achieved a good effect,with a wide application prospect.