特低渗透油藏二氧化碳吞吐模拟  

Simulation of carbon dioxide huff 'n' puff for reservoirs with extra low permeability

作　　者：钟立国[1,2,3] 韩大匡[2] 李莉[3] 赵明国[1] 

机构地区：[1]大庆石油学院提高采收率教育部重点实验室,黑龙江大庆163318 [2]中国石油勘探开发研究院博士后科研流动站,北京100083 [3]大庆油田有限责任公司勘探开发研究院,黑龙江大庆163712

出　　处：《大庆石油学院学报》2009年第4期120-124,共5页Journal of Daqing Petroleum Institute

基　　金：中国博士后基金项目(20080440924)

摘　　要：通过PVT筒和填砂管气液平衡等模拟实验,测定原油与CO2体系的黏度、膨胀因数和最小混相压力等高压物性参数,研究了恒压和降压(吐)下5次CO2接触过程中原油和气体的产量变化,并对比研究模拟特低渗填砂管与PVT筒CO2吞吐实验的开采动态.结果表明,注入CO2使原油的膨胀因数、体积因数和气油体积比增大,黏度和密度降低;CO2对原油的萃取作用明显,采出流体的密度低于原油,且注入压力越高萃取作用越强;在特低渗透多孔介质条件下,CO2与原油能够在48 h内达到气液平衡.因此,特低渗透油藏CO2吞吐采油技术可行,较高注入压力和达到气液平衡对保证吞吐效果非常重要.Based on PVT and sand packed tube,the high pressure characteristics such as viscosity,expansion coefficient and minimum miscibility pressure were measured for mixture of crude oil and carbon dioxide,and the oil and gas production during multi contact experiments under constant and declined('Puff') pressure was investigated,Lastly,the production performance of sand packed tube similar to low permeable reservoir.It shows that the expansion coefficient,volume coefficient and ration of gas to oil increased for carbon dioxide injection,at the same time,viscosity and density of oil decreased.Remarkable vaporization effect on crude oil is observed in carbon dioxide huff 'n' puff.As a result,the density of vaporized fluid is lower than crude oil as the carbon dioxide is pressured.Additionally,equilibrium of oil and carbon dioxide could be achieved in extra low permeable porous media in operational time(48 h).In summary,carbon dioxide huff 'n' puff is technically feasible for extra low permeable reservoir,and the higher injection pressure and gas-liquid equilibrium are significant for guaranteeing the favorable oil recovery.

关 键 词：特低渗透油藏 二氧化碳 吞吐 气液平衡 萃取作用 

分 类 号：TE345[石油与天然气工程—油气田开发工程]