中国石油大学学报（自然科学版）2025，Vol.49Issue(3)：125-131,7.DOI:10.3969/j.issn.1673-5005.2025.03.013
深水钻遇型水合物层稳定的固井调控方法及评价指标
Methods and evaluation indexes of cementing regulation for stabilization of drilled hydrate layers in deep-water oil and gas development
摘要
Abstract
In the process of deepwater oil and gas development,cementing is commonly used to seal and stabilize the gas hy-drate layer,ensuring its stability and preventing unexpected drilling incidents.However,during later stages of deepwater oil and gas production operations,the fluid in the oil pipe carries the heat from the formation to the shallow layer,causing tem-perature increase in the shallow formation.This can lead to thermal decomposition of the gas hydrate layer,and potentially result in the abandonment of the production wells.In order to address this technical challenge,the requirements for the sta-bility of the hydrate layer in deepwater cementing were figured out firstly in this study,and then the evaluation criteria for the thermal performance of the cement ring in shallow deepwater cementing were established based on theoretical analysis and de-rived calculations.A chart for regulating the thermal conductivity coefficient of the cement ring was developed,forming a ce-menting regulation method to ensure the stability of the hydrate layer in the upper layers of deepwater oil and gas production.The results show that,as the temperature of the oil and gas reservoir increases,the requirements for the thermal conductivi-ty coefficient of the cement ring,which guarantees the stability of the hydrate,become increasingly stringent,with a narro-wer range for adjustment.If it is difficult to regulate the thermal conductivity coefficient of the cement,alternatively,in-creasing the thickness of the cement ring can also ensure the stability of the hydrate.Based on the well structure and pro-duction parameters of a well in the South China Sea,comprehensive evaluation criteria for thermal insulation cementing were established,which require a compressive strength of the cement paste not less than 3.5 MPa at 24 h and a thermal conductivity coefficient not higher than 0.283 W·(m·K)-1 within 180 d,under the condition of a certain thickness of the cement ring.关键词
深水油气开发/固井调控方法/保温水泥/评价指标Key words
deepwater oil and gas development/well cementing control method/thermal insulation cement/evaluation inde-xes分类
能源科技引用本文复制引用
沈晟达,步玉环,路畅,柳华杰,郭胜来,刘和兴,张英男..深水钻遇型水合物层稳定的固井调控方法及评价指标[J].中国石油大学学报（自然科学版）,2025,49(3):125-131,7.基金项目
国家自然科学基金项目(51974355) （51974355）
江苏省基础研究计划自然科学基金项目(BK20220623) （BK20220623）
