摘要
大牛地气田下古生界碳酸盐岩储层低孔、低渗,自然产能低。前期采用水平井多级管外封隔分段酸压改造,压后产气量递减速率较快,稳产效果差,严重制约着气藏的高效开发。结合水平井分段酸压工艺,考虑酸液在裸眼井段中的径向滤失,采用Willianms-Nierode酸液有效作用距离计算图版,分析酸液的有效作用距离。结果表明:酸液在水平井段内的径向滤失严重,滤失速率高达1.9 m/min,而酸液的有效作用距离仅为动态缝长的20%左右,酸液在裸眼井壁的径向大量滤失导致酸蚀主裂缝缝长过短是影响酸压效果的主要因素。
The lower Paleozoic carbonate reservoir of Daniudi gasfield, featured by low porosity, low permeability, and poor natural productivity, was stimulated by staged acid fracturing of horizontal well using multi-level external casing packer. And poor yield stability with fast decline of post-frac production was obtained. It constrains seriously the high-efficient development.Based on the staged acid fracturing technology, considering the radial filtration of acid in open-hole section, this paper analyzes the effective operating distance of acid using the Willianms-Nierode Plate. The results show that there appears serious radial filtration in horizontal well section with filtration rate of 1.9m3/min, and the effective operating distance is only about 20% of the dynamic fracture length. Therefore, the serious radial filtration leading to short length of acidized major fractures is the main factor influencing on acid fracturing.
出处
《天然气勘探与开发》
2015年第4期44-47,12,共4页
Natural Gas Exploration and Development
基金
国家科技重大专项(2011ZX05045-03)"鄂尔多斯盆地大牛地致密低渗气田开发示范工程"子课题"下古生界碳酸盐岩储层酸液体系研究"
关键词
大牛地气田
碳酸盐岩
酸压
有效作用距离
Daniudi gasfield,carbonate rock,acid fracturing,effective operating distance
