摘要
长庆油田Y19井区是典型的低渗透底水油藏,目前该区块含水急剧上升,产量递减快,亟需增油提效。为此开展了该油藏剩余油分布规律和富集区挖潜措施研究。研究表明:Y19井区低渗透油藏剩余油富集原因是注采不平衡、井网不完善、储层非均质性和底水锥进,剩余油富集的主控因素是底水锥进和储层非均质性。对于由底水锥进导致剩余油富集的井,采取聚合物微球调驱及封堵底水的措施增产效果最好,可增加产量2.03倍。堵水的效果好于聚合物微球调驱的效果。对于由储层非均质性导致剩余油富集的井,在低含水阶段进行小规模压裂,可动用注采井之间低渗储层的原油;在中高含水阶段进行转向压裂,避免水线过快推进导致生产井过早见水;在高含水阶段采取侧钻,可动用注采井侧向的剩余油,最佳的裂缝转向角度为45~90°。
Y19 well block in Changqing Oilfield is a typical low-permeability bottom water reservoir.At present,the water cut in this block increases sharply and the production decreases rapidly,so it is urgent to increase oil production and improve efficiency.Therefore,the remaining oil distribution law and potential tapping measures in the remaining oil enrichment areas were studied.The research shows that the reasons for remaining oil enrichment in low permeability reservoir in Y19 well block are injection-production imbalance,imperfect well pattern,reservoir heterogeneity and bottom water coning.The main controlling factors for remaining oil enrichment are bottom water coning and reservoir heterogeneity.For the wells with residual oil enrichment caused by bottom water coning,the measures of polymer microsphere profile-control and flooding,and bottom water plugging have the best stimulation effect,which can increase the production by 2.03 times.The effect of bottom water plugging is better than that of polymer microsphere profile-control and flooding.For the wells with rich residual oil caused by reservoir heterogeneity,small-scale fracturing can be used at low water cut stage in order to exploit the crude oil between injection and production wells;steering fracturing can be used at medium and high water cut stage to avoid premature water breakthrough of production wells due to too fast advance of water line;sidetracking is adopted in high water cut stage in order to exploit the remaining oil at the side of injection and production wells.The best fracture turning angle is 45°~90°.
作者
李向平
段鹏辉
汪澜
康博
李转红
LI Xiangping;DUAN Penghui;WANG Lan;KANG Bo;LI Zhuanhong(Oil & Gas Technology Research Institute,PetroChina Changqing Oilfield Company,Xi’ an,Shaanxi 710018,China;National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields,Xi’ an,Shaanxi 710018,China)
出处
《西安石油大学学报(自然科学版)》
CAS
北大核心
2022年第4期69-75,126,共8页
Journal of Xi’an Shiyou University(Natural Science Edition)
基金
中国石油天然气股份有限公司科技项目“水平井重复改造技术与工具研究”(2021DJ4503)。
关键词
低渗透油藏
底水油藏
剩余油分布
富集模式
挖潜措施
low permeability reservoir
bottom water reservoir
remaining oil distribution
oil remaining enrichment pattern
stimulation measures
作者简介
第一作者:李向平(1979-),男,高级工程师,研究方向:老油田增产改造技术,E-mail:lxiangp_cq@petrochina.com.cn。