酸化技术在松南火山岩气田水平井的应用

Application of Acid Stimulation Technology in Horizontal Wells of Songnan Volcanic Rock Gas Field

松南火山岩气田主要发育两种火山岩相,前期投产层位主要以流纹岩为主,气田实现高效开发。2015年之后通过气藏调整挖潜,在凝灰岩底部与流纹岩顶部之间部署了X5井,该井受钻井液漏失影响,近井地带存在污染,受井下管柱影响,该井无法实施压裂,转为酸化投产。本文通过研究水平段工艺,制定合理的酸化作业管柱,确保对储层污染段进行重点处理,恢复气井产能;另外从储层粘土矿物,温压系统,岩芯、钻井泥浆的酸化溶蚀试验等方面开展研究,研发了一套适合于松南火山岩的酸液体系,在酸化投产后取得了较好的效果,为松南火山岩其它气井酸化作业提供了较好的技术支撑。

Two kinds of volcanic facies are mainly developed in Songnan volcanic rock gas field, and the early production has been mainly carried out in fluvial rocks, then the gas field was efficiently developed. After 2015, X5 well was deployed between the bottom of tuff rock and the top of rhyolite rock through the exploration of gas reservoir. This well was affected by the leakage of drilling fluid, and there was pollution in the near-well zone. Under the influence of tmderground pipe string, the well was not able to be fractured, so it was converted to acidized production. In this paper, the horizontal section technology was studied, and a reasonable acidizing operation pipe string was developed to ensure that the reservoir pollution section was treated emphatically and the gas well productivity was restored. In addition, some researches were carried out from the aspects of reservoir clay minerals, temperature pressure system, acidizing corrosion test of core and drilling mud; a set of acid liquid system suitable for volcanic rocks in Songnan volcanic rock was developed, and good results were achieved after acidizing production, which could provide good technical support for other gas well acidizing operations of volcanic rocks in Songnan.