有限圈闭复杂沥青质稠油层钻井难点与对策

Difficulties and Solutions for Drilling in Finite Geological Structure Trap Asphaltene Heavy Oil Layer

摘要:

中东YD油田为海相碳酸盐岩地层，Kazh地层分布着活跃的非均质沥青质稠油，高压并含有酸性气体，为非目的层，需要钻穿并封隔该层后对下部产层进行开发。由于沥青质稠油层分布不均，孔隙压力不确定，对钻井工程造成了极大的挑战。在一期施工中，3口井由于沥青质稠油的侵入被迫工程弃井，未能实现工程目的。针对此世界性难点问题，开展了沥青质稠油侵入机理实验研究、固化剂研制、控压钻井技术应用等一系列配套工艺技术研究，提出了复杂沥青质稠油层安全钻井技术对策，现场应用取得较好的效果。

Abstract:

Oilfield YD is one of marine strata carbonate reservoir in Middle East, active heterogeneous asphaltene heavy oil are distributed in Kazh formation with high pressure and acidic gas; being non-target layer, Kazh formation should be drilled through and isolated, then the lower payzone can be developed. Uneven distribution of asphaltene heavy oil and uncertain pore pressure bring severe challenges to drilling construction. Because of asphaltene heavy oil intrusion, 3 wells had to be abandoned in the first phase construction. In view of this world difficult problem, the technical study was made with some results. This paper discusses the experimental study on the intrusion mechanism of asphaltene heavy oil, the development of hardening agent, the application of managed pressure drilling technique and a series of associated technology research, proposes the safe drilling measures for asphaltene heavy oil layer and presents the field application effects.