中俄东线楚州盐穴储气库配套钻井液技术

Drilling fluid technology for Chuzhou salt-cavern gas storagefor Sino-Russian east gas pipeline

摘要:

楚州盐穴储气库是中俄东线配套储气库，具有重要建设意义。在楚州地区钻井施工时，上部东台组、盐城组地层易渗漏，粘土易造浆，下部浦口组含盐地层易溶蚀扩径和坍塌。针对楚州地区地层特点和施工难点提出采用分段钻井液技术：一开采用聚合物钻井液，防止表层漏失和坍塌；二开上部采用盐水聚合物钻井液，防止缩径和石膏侵；盐层段采用饱和盐水聚合物钻井液防止盐岩溶解。通过现场3口资料井对上述钻井液技术进行了验证，3口井钻井过程顺利，井径规则，未发生任何井下复杂情况，井身质量较高，盐层段岩心采取率均在99%以上。所形成的钻井液技术对建库钻井具有很好的指导意义。

Abstract:

The Chuzhou salt-cavern gas storage facilities is supporting gas storage for Sino Russian East Line; thus, it is of great construction significance. During the drilling operation in the Chuzhou area, the upper Dongtai and Yancheng formations are prone to leak, and the clay is prone to make slurry. The salt formations in the lower Pukou formation are prone to erode, expand and collapse. Drilling fluid technology for different well sections was used according to stratum characteristics and construction difficulties in the Chuzhou area. The polymer drilling fluid was used to prevent surface leakage and collapse in the first well section. The salt water polymer drilling fluid was used to prevent shrinkage and gypsum invasion in the upper part of the second section and the saturated brine polymer drilling fluid was used to prevent salt dissolving in the salt layer section. The above drilling fluid technology has been verified by 3 wells in the field. The drilling process of the 3 wells was smooth, the well diameter was regular, no downhole complications occurred, the quality of the well was high, and the coring rate of the salt layer was above 99%. The drilling fluid technology can provide good guidance for drilling of gas storage wells.