交联聚合物溶液突破性能

Breakthrough Performance of the Linked Polymer Solution

交联聚合物溶液(LPS)是由低浓度部分水解聚丙稀酰胺和交联剂柠檬酸铝形成的交联聚合物线团(LPC)在水中的分散体系。采用毛玻璃模型驱油实验和核孔膜过滤实验研究了LPS的突破性能以及再封堵特性。实验结果表明,LPS在多孔介质吸附滞留封堵后可以产生突破,突破后还具有再次封堵特性,能够起到更好的深部调剖效果;LPS封堵后突破压力与封堵强度有关,在缓慢升压的情况下,LPC不断的滞留、聚集,形成‘滤饼’,封堵强度越来越大,需要很高的压力才能够使封堵的LPC克服LPC与多孔介质的吸附力以及LPC分子间力产生突破,在封堵强度较低的情况下必须有一个较高的冲击力才能使封堵的LPC发生突破;形成LPS聚合物相对分子质量越高或者封堵的多孔介质孔径越小则其突破压力越大。

The linked polymer solution （LPS） is an aqueous dispersive system of the linked polymer coils （LPC） formed by the lower concentration intra-molecular crosslink of polymer （HPAM） and linking agent （AlCit）. The breakthrough and replugging properties of LPS were investigated by using nuclear pore membrane test and flooding test in a coarse-glass model. The results show that LPS could break through the pores of porous media plugged by LPC; LPC could continually plug the pores of porous media after each breakthrough which can modify the in-depth permeability of the reservoir. The breakthrough pressure is related to the strength of plugging. As injection pressure gradually increases, the strength of plugging becomes stronger by adsorbing retention, aggregation of LPC and formation of filtrating‘cake＇, so higher pressure is needed for plugging LPC to overcome the interaction between LPC and the surface of porous media and the interaction between LPCs. For lower strength of plugging, a sudden high repulsion force is needed for LPC to break through the pores of porous media plugged by LPC. The higher relative molecular mass of the polymer （HPAM）, or the smaller diameter of plugged pore, the higher breakthrough pressure is needed.