鄂尔多斯盆地不同类型储集层水驱油特征实验  

Experimental study on the oil production characteristics during the waterflooding of different types of reservoirs in Ordos Basin,NW China

作　　者：肖文联[1] 杨玉斌 李闽[1] 李农[2] 尤靖茜[3] 赵金洲[1] 郑玲丽[1] 周克明[2] 任吉田 王玥[1] XIAO Wenlian;YANG Yubin;LI Min;LI Nong;YOU Jingxi;ZHAO Jinzhou;ZHENG Lingli;ZHOU Keming;REN Jitian;WANG Yue(State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu 610500,China;PetroChina Southwest Oil and Gas Field Branch,Chengdu 610213,China;PetroChina Changqing Oilfield Company,Xi’an 710018,China)

机构地区：[1]西南石油大学油气藏地质及开发工程国家重点实验室,成都610500 [2]中国石油西南油气田公司,成都610213 [3]中国石油长庆油田分公司,西安710018

出　　处：《石油勘探与开发》2021年第4期807-816,共10页Petroleum Exploration and Development

基　　金：国家自然科学基金联合基金重点支持项目“黏度可控的原位增黏体系构建及高效驱油机理研究”(U19B2010);西南石油大学非常规油气渗流物理青年科技创新团队(2018CXTD10)。

摘　　要：以鄂尔多斯盆地低渗透、特低渗透和超低渗透储集层岩心为研究对象,通过岩心微观可视化水驱油实验和柱塞岩心水驱油核磁共振实验,揭示不同类型储集层水驱油过程中原油赋存状态、动用特征以及剩余油分布,分析孔隙结构和驱替压力对水驱油效率的影响。研究表明,在束缚水状态下,低渗透储集层岩心中原油主要赋存于中—大孔隙,而小孔隙和中等孔隙是特低渗透储集层和超低渗透储集层岩心中原油的主要分布空间。水驱油过程中,3类储集层岩心优先动用中—大孔隙中的原油;随着储集层岩心渗透率的逐渐降低,水驱前缘依次表现出均匀驱替、网状驱替和指状驱替,且驱油效率依次降低。水驱油结束后,低渗透储集层岩心中剩余油主要分布于中等孔隙,且以膜状和角状的分散相为主;特低渗透和超低渗透储集层岩心中剩余油主要分布于小孔隙,且以分散相和绕流形成的连续相为主。低渗透岩心具有较高的稳定驱油效率,特低渗透和超低渗透岩心驱油效率较低,且随着驱替压力的增加表现出一定程度的增加。图14表1参38。Waterflooding experiments were conducted in micro-models(microscopic scale)and on plunger cores from low permeability,extra-low permeability and ultra-low permeability reservoirs in the Ordos Basin under different displacement pressures using the NMR techniques to find out pore-scale oil occurrence state,oil production characteristics and residual oil distribution during the process of waterflooding and analyze the effect of pore structure and displacement pressure on waterflooding efficiency.Under bound water condition,crude oil mainly occurs in medium and large pores in the low-permeability sample,while small pores and medium pores are the main distribution space of crude oil in extra-low permeability and ultra-low permeability samples.During the waterflooding,crude oil in the medium and large pores of the three types of samples are preferentially produced.With the decrease of permeability of the samples,the waterflooding front sequentially shows uniform displacement,network displacement and finger displacement,and correspondingly the oil recovery factors decrease successively.After waterflooding,the residual oil in low-permeability samples is mainly distributed in medium pores,and appears in membranous and angular dispersed phase;but that in the extra-low and ultra-low permeability samples is mainly distributed in small pores,and appears in continuous phase formed by a bypass flow and dispersed phase.The low-permeability samples have higher and stable oil displacement efficiency,while the oil displacement efficiency of the extra-low permeability and ultra-low permeability samples is lower,but increases to a certain extent with the increase of displacement pressure.

关 键 词：水驱油特征 原油赋存状态 剩余油分布 核磁共振 驱替效率 鄂尔多斯盆地 

分 类 号：TE311[石油与天然气工程—油气田开发工程]