树脂球堵漏工艺在塔中区块的应用及认识

Research and Application on Resin Pill to Cure Malignant Lost Circulation in Central Tarim Oilfield

塔里木中部地区奥陶系油藏主要采用水平井开发模式实施长段地质目标穿越,钻井深度普遍在7 000 m左右。目的层奥陶系储层地质条件复杂、缝洞发育、钻井液安全密度窗口超窄,钻井过程中普遍发生恶性漏失,严重制约了该油藏的勘探开发进程。由于大型溶洞和裂缝的存在,传统堵漏材料结合常规堵漏技术治理塔中地区奥陶系恶性漏失成功率较低;为此,文章分析了塔中奥陶系储层漏失特征和堵漏难题,在此基础上提出了“投球架桥变缝洞为孔,多种堵漏材料协同充填封堵”的树脂球堵漏工艺技术。树脂球堵漏技术在X井恶性井漏治理中的成功应用表明,该技术可有效解决塔中区块大型缝洞恶性漏失问题。文章研究成果为塔中区块奥陶系恶性井漏的治理提供了一种新技术思路,将有助于提高该区块的堵漏作业效果。

In the Ordovician reservoirs of central Tarim area, horizontal wells are mainly used to cross the long geological targets, and the drilling depth is generally about 7 000 m. The target Ordovician reservoir is with complex geological conditions, well developed caves and extremely narrow safety density window of drilling fluid, leading to malignant loss in the process of drilling, which seriously restricts the process of reservoir exploration and development. Due to the large karst caves and cracks, the success rate of traditional lost circulation materials combined with conventional lost circulation control technology is quite low for solving the malignant loss problem of Ordovician in central Tarim oilfield. Therefore, this paper analyzes the loss characteristics and lost circulation control challenges of the Ordovician reservoir in central Tarim oilfied. On this basis, the integrated resin pill lost circulation treatment technology is put forward, which is to drop the resin pill as bridge to change the cave into pore and various kinds of lost circulation materials work together to fill and seal. The successful application of the resin pill lost circulation treatment technology in ZG11-H13 well with malignant lost circulation shows that this technology can effectively solve the problem of malignant loss for large fractures and holes in central Tarim oilfield. The research results provide a new technical idea for the treatment of malignant lost circulation in Ordovician reservoir, which will help to improve the effect of the lost circulation treatment operation in central Tarim oilfield.