超低渗油藏在线分流酸化增注技术研究与应用  

Study and application of online diversion acidizing technology in injection wells in ultra-low permeability reservoirs

作　　者：邓志颖 张随望[1,2] 宋昭杰[1,2] 王尔珍 杨乾隆[3] 吴文超 Deng Zhiying;Zhang Suiwang;Song Zhaojie;Wang Erzhen;Yang Qianlong;Wu Wenchao(National Engineering Laboratory of Exporting and Development of Low-Permeability Oil/Gas Fields,Xi’an,Shannxi 710018,China;Oil & Gas Technology Research Institute of Chanqing Oilfield Branch Company,PetroChina,Xi’an,Shannxi 710018,China;No.10 Oil Production Plant of Changqing Oilfield Branch Company,Qingyang,Gansu 745100,China;Shaanxi Mingde etroleum Technology Co.,Ltd.,Xi’an,Shaanxi 710018,China)

机构地区：[1]低渗透油气田勘探开发国家工程实验室,陕西西安710018 [2]中国石油长庆油田分公司油气工艺研究院,陕西西安710018 [3]中国石油长庆油田分公司第十采油厂,甘肃庆阳745100 [4]陕西明德石油科技有限公司,陕西西安710018

出　　处：《石油与天然气地质》2019年第2期430-435,共6页Oil & Gas Geology

基　　金：国家科技重大专项(2016ZX05023-005)

摘　　要：酸化是超低渗油藏最有效的增注措施之一,但由于储层物性差、非均质性强等问题,造成目前常规酸化措施普遍具有施工周期长、有效率低、有效作用距离短等不足,且酸化过程中存在指进现象和储层二次伤害。针对这一问题,选取鄂尔多斯盆地环江油田三叠系超低渗油藏为研究对象,提出了在线分流酸化技术,并配套研制了一种多元缓速螯合酸COA-1S和一种新型的水溶性分流剂COA-1P。通过室内评价实验和在线分流酸化模拟实验,发现该技术在缓速性、配伍性、水溶性、螯合能力和暂堵功能等方面均显著优于常规酸化;现场先导性实验结果表明,酸化后剖面吸水均匀程度从28. 5%上升至50. 9%,视吸水指数增加2倍左右,降压增注效果显著;同时,该技术还具有"不停井、不泄压、不动管柱、不返排"的特点,简化了常规分流酸化工序、降低了安全环保风险,是一种能够很好地适应超低渗油藏特征的酸化增注技术。Acidification is one of the most effective injection stimulation methods in the ultra-low permeability reservoirs.These reservoirs however,are usually characterized with poor physical property and high heterogeneity,leading to an unnecessarily long operation period,low efficiency,and insufficient effectively-operating distance for conventional acidification measures,as well as fluid fingering and secondary damage to the reservoir during the acidizing process.In this regard,we studied the Triassic ultra-low permeability reservoir in the Huanjiang oilfield,Ordos Basin,proposed the online diversion acidizing technology and developed COA-1S achelating acid system and COA-1P,a new water soluble diversion agent.After a large number of laboratory experiments,we found that,compared with the conventional acidizing method,this new technology is more retardant,compatible,water-soluble,and better at chelating and temporary blocking.In-situ pilot test has shown that the homogeneity of the water absorption profile has increased from 28.5 % to 50.9 %,that is,the water injectivity index doubled after the implementation of this technology.Meanwhile,its characteristics of “zero well shut-off and depressurization,zero impact on the tubing strings,and zero flow-back”,allows this technology to simplify the operation process of diversion and acidification,reduce the risks in security and environment protection,and thus can be recommended as a new acidification technology for stimulating injection of wells in the ultra-low permeability reservoirs.

关 键 词：螯合酸 分流剂 降压增注 超低渗油藏 在线分流酸化 

分 类 号：TE357[石油与天然气工程—油气田开发工程]