套管锻铣开窗技术在土耳其贝帕扎里碱矿中的应用

Application of casing section-milling technology in Beypazari Trona Mine in Turkey

摘要:

土耳其贝帕扎里碱矿在矿区边缘的碱层出现埋深起伏大、厚度变化大、易尖灭、易涌水等情况，这些特殊的地质情况导致水溶开采钻井过程中同一组井的套管最终下入到了不同的层位，或是原先下入的矿层不稳定，易坍塌。为了解决以上问题而引入了套管锻铣开窗技术。该技术可以将老井眼中已被套管封闭的上部碱层暴露出来形成新的采矿通道，从而提高矿区采收率。先后在14口老井眼中完成了套管锻铣作业，均达到了预期效果。本文介绍了套管锻铣器的工作原理，并以H066井组为例，详细阐述了套管锻铣开窗工艺技术。工程实践表明，套管锻铣开窗技术对于换层开采、钻井处理事故、事故井恢复性生产等方面具有一定的效果，具有减少钻井工期、降低施工成本、延长老井使用寿命、提高矿藏产量等优点，有广阔的应用前景。

Abstract:

The Beypazari Trona Mine in Turkey has the characteristics of varying buried depth and thickness and proneness to pinch out, and water kicks occurs frequently while drilling at the edge of the mining area, which leads to different casing setting positions in the vertical wells of the same solution mining well set, or the mining trona layer where casing has been set is unstable and needs to be changed. In order to solve these problems, the section-milling technology was introduced and applied to expose the previously isolated trona bed and form a new mining passage. A total of 14 wells were drilled by applying this technology on the project, and all achieved satisfied results. In the paper, the section-milling process is illustrated by taking the drilling of the H066 well set as an example. Comparing with drilling a new well, it reduces greatly the construction period and saves drilling costs. Field use demonstrated that the technology is beneficial in changing the mining layer, treatment of downhole incidents, and provides many advantages such as less drilling time, less drilling cost, extension of the service life of old wells, increasing of resource recovery; therefore it has a broad application prospect.