氮气泡沫在浅薄层超稠油油藏开发中的适用性  

Applicability of Nitrogen Foam in Developing Shallow⁃Thin Ultra⁃Heavy Oil Reservoirs

作　　者：常泰乐 杨元亮 高志卫 胡春余 郑孝强 张萌 袁一平 CHANG Taile;YANG Yuanliang;GAO Zhiwei;HU Chunyu;ZHENG Xiaoqiang;ZHANG Meng;YUAN Yiping(Xinjiang Xinchun Petroleum Development Co.,Ltd.,Sinopec,Dongying,Shandong 257000,China)

机构地区：[1]中石化新疆新春石油开发有限责任公司,山东东营257000

出　　处：《新疆石油地质》2021年第6期690-695,共6页Xinjiang Petroleum Geology

基　　金：国家重点研发计划项目(2018YFA0702400);中国石化重点科技攻关项目(P18050-1)。

摘　　要：春风油田排601中区、排6南区新近系沙湾组超稠油油藏具有埋藏浅、油层薄、原始地层压力小、地下原油黏度高等特点,主要采用水平井-降黏剂-蒸汽-氮气复合开发模式。多轮次吞吐后,地层压力下降,边底水突破油水界面发生锥进,面临油井排水期长、周期累计产水量增加、有效生产时间变短等问题,导致最终采收率较低。为此,开展了氮气泡沫辅助蒸汽吞吐实验,通过室内实验和数值模拟,进行泡沫适用性筛选及注入参数和工艺优化。现场应用效果表明,在边底水入侵区块采用氮气泡沫辅助蒸汽吞吐,较上一周期平均排水期缩短8.3 d,含水率下降32.2%,累计产油量增加2606.0 t;在吞吐高周期区块,注入氮气泡沫可使周期含水率降低8.6%,累计产油量增加1668.0 t,表明氮气泡沫可有效提高地层能量和封堵大孔隙通道,达到调整吸汽剖面的目的,在提升最终采收率方面起到了关键作用。Located in the Neogene Shawan formation in the central Block Pai 601 and southern Block Pai 6 of Chunfeng oilfield,the ultra⁃heavy oil reservoirs are characterized by shallow burial,thin pays,low original formation pressure and high crude oil viscosity.A compound method integrating horizontal well,viscosity reducer,steam with nitrogen is usually used to develop these reservoirs.After several cycles of huff and puff development,the formation pressure dropped,edge and bottom water broke through the oil⁃water contact and coned upward,resulting in a longer water drainage period,higher cumulative water production,and a shorter effective production period,and consequently relatively low ultimate oil recovery.Therefore,a steam huff and puff test assisted by nitrogen foam was carried out,and indoor experiments and numerical simulation techniques were used to analyze and compare foam applicability and optimize injection parameters and process.Field test results show that after applying steam huff and puff assisted by nitrogen foam in the blocks with edge and bottom water intrusion,the average water drainage period in the oil well was shortened by 8.3 days,the water cut decreased by 32.2%and the cumulative oil pro⁃duction increased by 2606.0 t.In the blocks after several cycles of huff and puff,injecting nitrogen foam reduced the water cut by 8.6%and increased the cumulative oil production by 1668.0 t,indicating that nitrogen foam can effectively increase formation energy,block large pore channels,adjust steam absorption profile and play a key role in improving the ultimate oil recovery.

关 键 词：浅薄层 超稠油油藏 氮气泡沫 蒸汽吞吐 性能评价 注入参数 注入方式 驱替效率 

分 类 号：TE341[石油与天然气工程—油气田开发工程]