高凝油油藏注普通冷水开采的可行性  

Feasibility of high pour point oil reservoir by ordinary cold water injection

作　　者：姚为英[1] 

机构地区：[1]辽河油田分公司勘探开发研究院开发所,辽宁盘锦124010

出　　处：《大庆石油学院学报》2007年第4期41-43,97,共4页Journal of Daqing Petroleum Institute

摘　　要：分析油藏近井地带和井筒在开采过程中温度的变化规律,进而确定高凝油油藏开发方式,可以最大限度提高原油采收率.根据高凝油油藏流体性质,通过室内实验和分析沈84-安12块注冷水驱油效果,认为注冷水后一般会在井底56-75 m半径内形成降温带,在不同注入孔隙体积倍数条件下温度下降一般小于30℃,即如果油层温度与高凝油析蜡温度的差值在30℃以上时,注普通冷水一般不会在油层造成蜡沉积.当析蜡温度接近地层温度时,会产生冷伤害,对其开发应采取相应措施使油层温度保持在原油析蜡温度以上.沈84-安12块开发实践表明,常温注水开发地层存在冷伤害.采用高压力梯度、大压差开采方式有利于改善高凝油油藏的开发效果.The changing rule of temperature near the vicinity of well bore and borehole during the producing process was analyzed,and then the development mode of high pour point oil reservoir was determined,which can maximize oil recovery.Based on the analysis of high pour point oil reservoir fluid properties,through the laboratory experiments and the displacement effect by cold water of Shen 84-An 12 block,it is considered that,after cold water injection,the cooled zone is formed at the bottom of the well within 56-75 m radius.The cooling value is usually less than 30 ℃ under different injection pore volume conditions.That is to say,if the temperature difference between reservoir and high pour point oil is above 30 ℃,injecting ordinary cold water usually does not cause wax deposit.While the wax precipitation temperature is close to the formation temperature,it will cause cold damage.Therefore,corresponding measures should be taken to make sure that the reservoir temperature is above wax precipitation temperature.The development practice of Shen 84-An 12 block shows that cold damage exists in normal temperature water flooding formation.When developing high pour point oil reservoir,high pressure gradient and big pressure difference are beneficial to improving the development effects of high pour point reservoir.

关 键 词：高凝油油藏 凝固点 析蜡温度 冷伤害 

分 类 号：TE112.26[石油与天然气工程—油气勘探]