基于纳米活性降压增注技术在低渗油田应用  

Application of Nano-active Depressurization and Injection Enhancement Technology in Low-permeability Oilfields

作　　者：张刚 成城 张卫平 ZHANG Gang;CHENG Cheng;ZHANG Wei-ping(Yanchang oil field,Dingbian oil production plant,Dingbian 710000,Shaanxi,China)

机构地区：[1]延长石油定边采油厂,陕西定边710000

出　　处：《合成材料老化与应用》2021年第2期89-91,共3页Synthetic Materials Aging and Application

摘　　要：纳米SiO_(2)粉体是一种新型的增强型注入剂,具有较强的疏水性和亲油性,能吸附在岩石表面,改变岩石的润湿性。它能有效地扩大孔隙半径,降低注入水在孔隙中的流动阻力,提高渗透率,降低注入压力,提高注入速度。利用模拟延边油田某厂地质条件的人工岩心,在注水开发后进行了SiO_(2)纳米粉体减压增注实验,选择了低渗透条件下SiO_(2)纳米粉体的最佳注入量。结果表明,纳米SiO_(2)粉体使岩石的润湿性由亲水性转变为疏水性。注水开发后原油采收率进一步提高。随着注入孔体积的增大,纳米SiO_(2)粉体驱替的回收率和减压率逐渐提高。最佳注入孔隙体积和注入浓度分别为0.6PV和0.5%,相应提高采收率为6.84%,减压率为52.78%。现场试验表明,在低渗透油田,纳米SiO_(2)粉体增注技术可以提高注水井的吸水能力,降低注入压力。因此,它是解决低渗透油田注水问题的有效方法。SiO_(2) nano-powder is a new type of augmented injection agent,has the ability of stronger hydrophobicity and lipophilicity,can be adsorbed on the rock surface so that it changes the rock wettability.It can expand the pore radius effectively,reduce the flow resistance of injected water in the pores,enhance water permeability,reduce injection pressure and augment injection rate.Using artificial cores which simulated geologic conditions of a certain factory in oil field,decompression and augmented injection experiments of SiO_(2) nano-powder were performed after waterflooding,best injection volume of SiO_(2) nano-powder under the lowpermeability condition was selected.It has shown that SiO_(2) nano-powder inverted the rock wettability from hydrophilicity to hydrophobicity.Oil recovery was further enhanced after waterflooding.With the injection pore volume increasing,the recovery and decompression rate of SiO_(2) nano-powder displacement increased gradually.The best injected pore volume and injection concentration is respectively 0.6 PV and 0.5%,the corresponding value of EOR is 6.84%and decompression rate is 52.78%.According to the field tests,it is shown that,in the low-permeability oilfield,the augmented injection technology of SiO_(2) nano-powder could enhance water injectivity of injection wells and reduce injection pressure.Consequently,it is an effective method to resolve injection problems for the low-permeability oilfield.

关 键 词：纳米SIO2 降压增注 采收率 亲油性 

分 类 号：TE348[石油与天然气工程—油气田开发工程]