压回法压井技术适用性研究

 利用非常规压回法压井技术在气侵或井喷发生后，通过压井管汇或钻具直接向井眼内泵入加重钻井液或原钻井液，将气体和已受污染的钻井液顶回到渗透性地层，重新平衡地层压力。针对某些类型的溢流井喷适用于压回法压井技术，分析了适用于压回法压井的侵入流体特征，地层物性特征等参数，给出了压回法适用的钻井现场工况，实施压回法压井的必要条件和所需装备，并进行了压回法压井实例分析，这可为现场工程技术人员选择合理的压井方法提供有益借鉴和指导。结合近几年国内出现的井涌、井喷事故特点，分析结果表明：压回法在应对浅层气溢流、高压气井溢流等复杂井溢流、井喷方面有着良好的适用性。

Applicability of Bullheading Killing Technology

The bullheading as an unconventional technique to kill a well is by pumping the kill fluid directly into the wellbore or the annulus during the gas kick, until all the influx is displaced into the exposed open hole formation and the wellbore is filled with a kill fluid of sufficient density to balance the reservoir pressure. For the type of blowouts applied by the bullheading technique, this paper analyzes the invasion fluid characteristics, the formation physical properties, and other parameters for the bullheading, identifies the applicable conditions, the necessary conditions and the required equipment for bullheading, and analyzes the field applications for bullheading to provide some guidelines for engineers. With considerations of the kick and blowout features in recent years, it is shown that the bulheading has a good prospect for the shallow gas well overflow, the high pressure gas well overflow, and other complex well overflows and blowouts.