Design And Application Of Non-alkaline Surfactants-polymer Combination Flooding In Liaohe Oilfield

Non-alkaline surfactants-polymer combination flooding is a kind of chemical flooding, which is the combination of surfactant and polymer. Non-alkaline surfactants-polymer combination flooding can effectively improve the development performance of old oil field which is water flooded, enhance oil recovery ratio dramatically. Widely use of non-alkaline surfactants-polymer combination flooding lays a solid foundation for extended application of chemical flooding in Liaohe Oilfield.Because there is no alkaline in SP combination flooding, the problem of crustation resulted from alkaline in formation will be avoided. However, without the help of alkaline, interfacial tension of oil-water contact will increase, so super-low(order of magnitude < 10-3mN/m) interfacial tension is difficult to acquired, therefore, improved displacement efficiency will decline, meanwhile, adsorbance of surfactant will greatly increase, thus to increase the cost.The article studies and analyses the design and application of in Liaohe Oilfield on the basis of system evaluation of chemical flooding, optimization of formula system and injection parameters, and field tracing monitor. A kind of surfactant, can be used in non-alkaline condition to achieve super-low interfacial tension(order of magnitude < 10-3mN/m) of oil-water contact, has been successfully advanced. Through laboratory experiments, the paper studies interfacial tension, stabilization, emulsion and absorbance of the surfactant, and conducts comparison analysis between non-alkaline surfactant-polymer combination flooding and alkalinesurfactant-polymer combination flooding by physical simulation. The result shows oil displacement efficiency of non-alkaline SP is the best. The paper optimizes surfactant concentration, slug size, polymer concentration and injection time of non-alkaline SP flooding system. With the help of field tracing monitor, ensure effectively implement non-alkaline SP flooding. Field application shows oil production increases while water production decreases in Jin-16 Block, which conduct non-alkaline SP flooding. Daily oil production increases from 61 t to 350 t, water content decline from 96.5% to 82.6 %, stage accumulated oil production 27.4 kt.