空气泡沫驱注入系统的腐蚀、地层伤害评价及其对策研究

发布时间：2018-10-24 09:52

【摘要】：空气泡沫驱在延长油田取得了较好的开发效果,但是其对注入系统的腐蚀、对地层伤害一直是制约该技术应用的瓶颈问题。针对空气泡沫驱注入系统的腐蚀机理、危害程度进行系统研究和评价,筛选出适合延长油田工况条件下的缓蚀剂,研究注入介质(泡沫、空气、地表水)与地层配伍性、从而评价空气泡沫驱对地层的伤害程度、并制定相应对策,是目前急需解决的关键问题。通过对注入系统腐蚀产物的分析可知腐蚀产物主要以氧化铁为主,次之为CaCO3,FeS、SiO2、Al2O3含量则相对较少。腐蚀试验说明:空气压力越高,腐蚀速率越快,这与腐蚀介质中氧分压的增大有关。泡沫液与空气交替注入次数越多,腐蚀速率越高,频繁交替注入使得水与氧气共存。温度越高、氧扩散越快,腐蚀越快。注入空气湿度越大,腐蚀速率越高。在注入系统的腐蚀防护方面,缓蚀剂CT2-17和牺牲阳极保护法可以较好的用于甘谷驿油田空气泡沫驱。在对地层伤害方面,空气与甘谷驿地层原油后会发生低温氧化反应,产生大量的CO2,酸性的二氧化碳气体会溶蚀多孔介质提高储层的渗透率,当地层水pH改变时易产生CaCO3沉淀。更重要的是地层中容易出现细菌堵塞,因此在注空气泡沫驱时需要加入杀菌剂。杀菌剂可有效降低腐蚀速率。起泡剂的腐蚀程度较轻,其中始创起泡剂C的性能最好,最适合甘谷驿油田的空气泡沫驱。本文结果对甘谷驿油田空气泡沫驱的腐蚀机理认识及采取有效的防护措施具有重要的指导意义。
[Abstract]:Air foam flooding has achieved good development effect in Yanchang Oilfield, but its corrosion to injection system and formation damage have been the bottleneck problems restricting the application of this technology. According to the corrosion mechanism and damage degree of air foam flooding injection system, the corrosion inhibitor suitable for prolonging the working conditions of oil field was screened out, and the compatibility of injected medium (foam, air, surface water) with formation was studied. Therefore, it is a key problem to be solved urgently to evaluate the damage degree of air foam flooding to formation and to formulate corresponding countermeasures. Through the analysis of the corrosion products of the injection system, it can be seen that the corrosion products are mainly iron oxide, followed by the content of CaCO3,FeS,SiO2,Al2O3 is relatively small. The corrosion test shows that the higher the air pressure, the faster the corrosion rate, which is related to the increase of oxygen partial pressure in corrosive medium. The higher the times of alternating injection of foam liquid and air, the higher the corrosion rate, and the higher the corrosion rate is, the more frequent alternate injection of water and oxygen makes the coexistence of water and oxygen. The higher the temperature, the faster oxygen diffusion and corrosion. The higher the air humidity, the higher the corrosion rate. In the aspect of corrosion protection of injection system, corrosion inhibitor CT2-17 and sacrificial anode protection can be used for air foam flooding in Ganguyi Oilfield. In terms of formation damage, air and Ganguyi formation crude oil will be oxidized at low temperature, and a large amount of CO2, acid carbon dioxide gas will dissolve the porous media to improve the permeability of the reservoir, and the formation water pH changes will easily produce CaCO3 precipitation. More importantly, bacterial clogging is easy to occur in the formation, so fungicides should be added to air foam flooding. Fungicides can effectively reduce the corrosion rate. The degree of corrosion of foaming agent is relatively light, among which the performance of foaming agent C is the best, which is the most suitable for air foam flooding in Ganguyi Oilfield. The results of this paper have important guiding significance for understanding the corrosion mechanism of air foam flooding and taking effective protective measures in Ganguyi Oilfield.
【学位授予单位】：西安石油大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TE357.46

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