注天然气油井沥青质析出规律研究  

Study on the precipitation regular of asphaltene in gas injection well

作　　者：曹立虎 吴鑫鹏 徐海霞 沈建新 黄龙藏 吴红军 熊瑞颖 郭继香[2] Cao Lihu;Wu Xinpeng;Xu Haixia;Shen Jianxin;Huang Longcang;Wu Hongjun;Xiong Ruiying;Guo Jixiang(Research Institute of Engineering Technology,PetroChina Tarim Oilfield Company,Xinjiang,China;Research Institute of Unconventional Oil and Gas,China University of Petroleum(Beijing),Beijing,China)

机构地区：[1]中国石油塔里木油田油气工程研究院 [2]中国石油大学(北京)非常规油气科学技术研究院

出　　处：《石油与天然气化工》2022年第2期88-93,共6页Chemical engineering of oil & gas

基　　金：国家自然科学基金“高温高压油井沥青质析出规律及机理研究”(52174047)。

摘　　要：目的解决东河区块原油在注气开采过程中沥青质沉积堵塞井筒问题。方法采用高温高压固相沉积规律测试装置,基于光散射理论,研究了温度、压力、气油比等因素对沥青质析出特征的影响。结果温度升高会增加沥青质在原油中的溶解度,促进原油稳定;等温降压过程中,沥青质随着压力降低逐渐析出,在泡点压力附近达到最大析出量,发生沥青质沉积堵塞油井的风险最大。DH-1井泡点压力对应井深2140 m,与油井生产实际遇阻位置1969 m接近,泡点压力可初步用于预测油井堵塞位置;溶解注气量越大,沥青质初始析出压力越大,沥青质析出压力区间也增大,沥青质沉积位置向油井深度下移。结论研究揭示了注气过程沥青质的析出规律,对注天然气油井沥青质析出防治具有重要指导作用。Objective This paper aims to solve the problem of asphaltene deposition blocking wellbore in the process of gas injection production of crude oil in Donghe block.Methods Based on light scattering theories and using a high pressure/high temperature solid deposition test device,the effects of temperature,pressure,gas-oil ratio and other factors on the precipitation behavior of asphaltenes were tested.Results Temperature increase improves the solubility of the asphaltene in the crude oil and promotes the stability of the crude oil.Under isothermal pressure depletion conditions,asphaltenes gradually precipitate and reach maximum precipitation near the bubble point pressure with the descend of pressure.In other words,the risk of asphaltene deposition is highest when near the bubble point pressure.The bubble point pressure of DH-1 well corresponds to the well depth of 2140 m,which is close to the actual blocked position at 1969 m in production well.Therefore,the bubble point pressure can be used to predict the plugging location in oil wells.The higher the amount of dissolved gas,the higher the onset asphaltene precipitation pressure,and thus the larger the asphaltene precipitation pressure range the more likely asphaltene deposits to occur in deeper well sections.Conclusion The research reveals the asphaltene precipitation law during gas injection,which has an important guiding role in prevention and control of asphaltene precipitation in gas injection wells.

关 键 词：东河油田 沥青质 光散射理论 注气开采 泡点压力 

分 类 号：TE357.7[石油与天然气工程—油气田开发工程]