煤层气井注水泥顶替效率研究  

Displacement efficiency of cementing in CBM well

作　　者：张立刚[1] 金显鹏[2] 吕德庆 

机构地区：[1]东北石油大学石油工程学院,黑龙江大庆163318 [2]大庆油田有限责任公司井下作业分公司,黑龙江大庆163412

出　　处：《煤田地质与勘探》2014年第3期43-46,共4页Coal Geology & Exploration

基　　金：国家自然科学基金项目(51274069);黑龙江省自然科学基金项目(E201015)

摘　　要：煤层低压、易塌、易漏造成煤层段井眼不规则,扩径严重,使注水泥过程顶替效率降低,影响水泥浆的封固效果。运用CFD数值模拟方法,结合鹤岗煤层气井测井数据,模拟了煤层段不同扩径长度、扩径率、井斜角、套管居中度、水泥浆流变参数及顶替流态下的体积顶替效率及截面顶替效率值;分析了各因素对顶替效率的影响规律。结果表明,扩径段长度增加,顶替效率提高;扩径率、井斜角及偏心度增加,顶替效率降低;宾汉流体及幂率流体均存在顶替效率最高的流变参数值,顶替流态建议采用塞流顶替。研究成果为煤层气井安全优质固井提供了技术指导。Due to some characteristics of the coal seam such as the low pressure, easy to collapse and leakage, re-sulting in the irregular borehole in coal seam segments and serious hole enlargement, the displacement efficiency in the process of cementing is reduced, which affects the sealing effects of slurry in cementing. In this paper, through the use of CFD numerical simulation method, combined with Hegang CBM well logging data, various parameters of the different coal seam segments such as the length of the hole enlargement, hole enlargement ratio, deviation angle, the centralisation degree of casing, the slurry rheological parameters and the value of volume displacement efficiency under the replacement fluid state and cross-sectional displacement efficiency are simulated. The influ-ence of various factors on the displacement efficiency is analyzed. The displacement efficiency will be improved with the length of the hole enlargement segment increasing. On the contrary it will be reduced with the hole enlargement ratio, the deviation angle and the eccentricity boosting. Bingham fluid and power law fluid both have the highest rheological parameter values of displacement efficiency. The plug flow displacement is recommended under replacement fluid states. The above research results have provided the technical guidance for the safe and high quality cementing of CBM wells.

关 键 词：煤层气 顶替效率 CFD数值模拟 注水泥 

分 类 号：P634[天文地球—地质矿产勘探]