凝析气藏反凝析污染研究

Pollution caused by retrograde condensate in condensate gas reservoir

肖丽仙 杜建芬 郭 平 杨素云 曾 珠

1．西南石油大学油气藏地质及开发工程国家重点实验室，四川 成都 610500 中国石油长城煤层气开发公司，辽宁 盘锦 124010 西南油气田分公司川中油气矿，四川 遂宁 629000

凝析气藏反凝析污染严重影响气井产能。因此，正确评价反凝析污染程度，寻找合适的解除反凝析污染方法，对提高凝析气藏采收率具有重要意义。在研究大量国内外文献的基础上，分析了凝析气井近井反凝析污染机理及其对产能的影响；总结了各种评价反凝析污染程度的方法，主要有气藏工程计算法、室内长岩心衰竭实验法、试井解释法和数值模拟评价法；详细阐述了各种解除反凝析污染、提高气井产能的方法，推荐采用循环注气和单井注气吞吐来解除反凝析污染。

Gas well productivity is affected by retrograde condensation pollution significantly in gas condensate reservoir, so how to evaluate the extent of retrograde condensation pollution correctly and find a proper way to remove condensate banking from the well are significant to enhance recovery of condensate gas reservoir. On the fundament of investigating great amount of literatures, the paper analyzes the retrograde condensation pollution mechanism in the vicinity of the wellbore and its effect to productivity, summarizes various methods to evaluate the level of pollution, mainly including gas reservoir engineering calculation, long cores depletion experiment, well test interpretation and numerical simulation. It also illustrates different
ways of removing condensate damage to improve gas well productivity. And cyclical gas injection and single well gas injection of huff and puff to relieve retrograde condensation pollution are recommended.