热化学复合酸化解堵技术研究

在稠油油藏进行常规酸化解堵易造成二次伤害，且残酸返排较难。以江苏油田W5块稠油为对象，开展了热化学复合酸化解堵技术研究，即优选合适的酸液配方，采用酸液溶蚀部分岩心及有机堵塞物，提高近井地带地层渗透率；同时在酸液中加入A剂，在后置液中加入B剂，分段注入后让其在地层中发生热化学反应，产生气体并放出大量的热，利用热化学反应产生的大量热量和气体，对地层有效升温，溶解有机物，降低原油粘度，促进残酸返排。优选出的多功能添加剂KB—28在降低表面张力和缓蚀性船上的作用较为明显，但抗酸渣的性能不强，因此在酸液中使用了抗酸渣剂KS—96。

Study on the thermochemistry complex acidizing in W5 heavy oil reservoir,Jiangsu Oilfield

As the secondary damage and difficult flowbacking of the reacted acid can be produced during the conventional acidizing in the heavy oil reservoir, a technology of thermochemistry complex a-cidizing has been studied in W5 heavy oil reservoir of Jiangsu Oilfield. i. e. , optimizing the acidizing formulation and using the acidizing fluid to corrode partial of the cores and organic bulkhead to improve the permeability of immediate vicinity of wellbore; adding agent A in acidizing fluid and agent B in overflush fluid and then injecting them into piecewise formations and making thermochemistry reaction in the formations, thus, a great deal of gas and heat are generated. Because of the gas and heat, the formations are heated up, the organic matter are dissolved, crude oil viscosity is thinned and the flowbacking of the reacted acid is forwarded. However, optimized multifunction additive KB-28 has poor acid resistance although it plays significant roles in cutting down superficial tension and corrosion mitigation, therefore, resist KB-96 is used in the acidizing fluid.