摘要
CO_(2)溶解度是影响低渗、致密油藏注CO_(2)提高采收率和深盐水层CO_(2)埋存效果的重要参数。基于高温高压可视化相态反应釜的CO_(2)溶解实验明确了地层温度和压力、地层水矿化度和多相流体饱和度变化对原油-地层水体系中CO_(2)溶解度的影响,并通过拟合实验结果建立地层温度及压力下原油-地层水体系CO_(2)溶解度预测模型。结果表明:原油-地层水体系中,CO_(2)溶解度受压力和流体类型影响较大,压力和含油饱和度越高,越有利于CO_(2)溶解,地层水矿化度和温度均能小幅度影响CO_(2)在地层水中的溶解度;CO_(2)在原油中的溶解呈现出多阶段溶解特征,并随含油饱和度的增大大幅增加;随着油水两相体系中含水饱和度的增大,CO_(2)溶解度迅速降低,且伴随温度的升高,CO_(2)溶解度小幅降低。基于CO_(2)溶解度实验拟合得到CO_(2)溶解度预测模型,油水两相体系中的CO_(2)溶解度可分别采用CO_(2)在原油、地层水中的溶解度对油水两相饱和度加权得到,模型计算结果与实验结果一致性较高。
CO_(2)solubility is a critical parameter impacting the effects of CO_(2)injection for enhanced oil recovery(EOR)in lowpermeability/tight reservoirs and CO_(2)storage in deep saline aquifers.By using a hightemperature,highpressure visualized phase reactor,CO_(2)dissolution experiments were conducted to investigate the influences of formation temperature/pressure,formation water salinity,and multiphase fluid saturation on solubility of CO_(2)in crude oilformation water systems.A prediction model for CO_(2)solubility in crude oilformation water systems under formation temperature and formation pressure was developed by fitting experimental data.The results show that in crude oilformation water systems,CO_(2)solubility is strongly influenced by pressure and fluid type,and higher pressure and oil saturation can promote CO_(2)dissolution.Both formation water salinity and temperature have minor impacts on solubility of CO_(2)in formation water.CO_(2)dissolution in crude oil exhibits multistage behaviors,and the CO_(2)solubility increases significantly with the increase of oil saturation.Moreover,CO_(2)solubility declines rapidly with increasing water saturation in oilwater systems and decreases slightly with increasing temperature.The solubility prediction model,derived from the fitting of experimental data,calculates CO_(2)solubility in twophase systems via saturationweighted contributions of the solubility in oil and water phases and the results show high consistency with the experimental results.
作者
杨宏楠
乐平
范伟
张维
汪周华
李丹宸
YANG Hongnan;YUE Ping;FAN Wei;ZHANG Wei;WANG Zhouhua;LI Danchen(State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu,Sichuan 610500,China;PetroChina Changqing Oilfield Company,Research Institute of Exploration and Development,Xi'an,Shaanxi 710018,China;PetroChina Changqing Oilfield Company,No.4 Oil Production Plant,Yinchuan,Ningxia 718500,China)
出处
《新疆石油地质》
北大核心
2025年第3期360-366,共7页
Xinjiang Petroleum Geology
基金
国家自然科学基金(U24B200683)
四川省自然科学基金(2024NSFSC2012)。
