注甲醇解除凝析气井反凝析污染的机理  

Mechanism of Eliminating Retrograde Condensate Damage in Gas Condensate Well by Methanol Injection Process

作　　者：石德佩[1] 李相方[1] 刘华[1] 孙雷[2] 

机构地区：[1]中国石油大学石油天然气工程学院,北京102249 [2]西南石油大学石油工程学院,成都610500

出　　处：《新疆石油地质》2007年第2期207-209,共3页Xinjiang Petroleum Geology

基　　金：国家"973"科技攻关项目;气/液/固复杂相变及渗流理论研究(2001CB209108);国家自然科学基金项目;深层含水凝析气藏多相渗流理论研究(90210018)

摘　　要：用PR状态方程计算气相组分逸度,建立了含醇类的烃-醇体系气-液相平衡计算模型;为了描述醇类的极性,用正规溶液理论借助活度系数计算了液相组分逸度,模拟了烃-醇体系的相态变化特征,揭示了注甲醇解除凝析气井近井带反凝析污染的机理。研究表明,在实例凝析气样的原始温度和压力下,随注入凝析气体系中甲醇摩尔分数的增加,体系的露点显著降低;模拟注入不同摩尔分数甲醇的凝析气体系的等组分膨胀和定容衰竭过程,结果表明,随甲醇摩尔分数增加,等组分膨胀过程中凝析液饱和度不断降低;定容衰竭过程中的反凝析液量和凝析液粘度也明显降低;甲醇对凝析油产生有效的再蒸发作用,是一种有效的解除反凝析污染的溶剂。By using PR state equation,the gas compositional fugacity is calculated,and the gas-liquid equilibrium model for hydrocarbon-methanol system is developed to simulate the phase behavior of this system in order to reveal the mechanism of eliminating retrograde condensate damage near wellbore in gas condensate well by methanol injection process.The study shows that the dew point pressure of this system can be reducedwith increase of injected methanol amount in gas condensate well under the real initial temperature and preure;the condensate saturation in constant composition expanding process will be cut down and the retrogade condensate amount and condensate viscosity are obviousl decreased in constant volume depletion process.It is concluded that methanol as an effective solvent for eliminating the retrograde condensate damage is of re-vaporizing effect on condensate oil.

关 键 词：甲醇 凝析气 反凝析 污染 相平衡 

分 类 号：TE372[石油与天然气工程—油气田开发工程]