鄂尔多斯盆地渭北油田长3储层注CO_2室内研究  

A Laboratory study on CO_2 injection of Chang 3 reservoir of Weibei oilfield in Ordos basin

作　　者：张本艳[1] 周立娟[2] 何学文[2] 王少朋[2] 闫梅 

机构地区：[1]中国石化西南油气分公司勘探开发研究院,四川成都610041 [2]中国石化华北油气分公司勘探开发研究院

出　　处：《石油地质与工程》2018年第3期87-90,共4页Petroleum Geology and Engineering

基　　金：国家科技重大专项"低丰度致密低渗油气藏开发关键技术"(2016ZX05048)

摘　　要：渭北油田WB2井区采用超前注水直注直采开发方式,开发效果不理想。通过渭北长3超低渗储层岩心物模室内实验,结合核磁共振数据,研究了水驱、CO_2驱、注水转注气3种方式的微观驱油机理。实验结果表明,渭北长3超低渗储层水驱驱油效率最低(37%),CO_2驱油效率更高(54.3%);水驱转气驱驱油效率最高(约55.7%)。通过核磁共振测量不同驱替方式后岩心的剩余油分布发现,直接水驱主要动用中、小孔隙中的原油,直接气驱更大程度动用的是中、大孔隙中的原油,而水驱转气驱能扩大波及范围,进一步动用大中小孔隙中的原油;注水转注CO_2有利于驱油效率的提高。WB2 well block of Weibei oilfield adopts the method of direct injection and production, but the development effect is not ideal. Through laboratory experiment of physical models of Chang 3 ultra–low permeability reservoirs in Weibei oilfield, in combination with nuclear magnetic resonance data, the microscopic displacement mechanism of water flooding, CO2 flooding and the manner of water injection to gas injection flooding was studied.The experimental results indicate that the water flooding efficiency is the lowest(37%), the CO2 flooding efficiency is higher(54.3%), and the oil efficiency of water flooding to gas flooding is the highest(about 55.7%). By use of the nuclear magnetic resonance(NMR) to measure different displacement models of the cores, it is found that the residual oil distribution is directly used in medium and small pores in water flooding, while gas flooding is directly used in crude oil of medium and large pores, and the manner of water flooding to gas flooding can be expanded into a larger cope, it can be further used in the crude oil of medium pores. It is feasible of CO2 injection after water injection to enhance the displacement efficiency for Chang 3 reservoirs in Weibei oilfield.

关 键 词：渭北油田 超低渗储层 核磁共振 CO2驱 微观驱油机理 

分 类 号：TE348[石油与天然气工程—油气田开发工程]