元坝气田环空带压井风险级别判别模式研究  

Risk Level Evaluation Model for Wells with Sustained Annular Pressure in Yuanba Gas Field

作　　者：陈曦[1] 孙千[1] 徐岭灵 庄园[1] 袁淋[1] 

机构地区：[1]中国石化西南油气分公司川东北采气厂,四川阆中637400

出　　处：《中外能源》2017年第3期57-62,共6页Sino-Global Energy

摘　　要：气井环空带压是元坝气田面临的普遍问题,其严重威胁到气井安全生产,需要进行完整性评价,判别风险级别,提出应对措施。基于环空带压的原因分析,结合元坝气田现场经验,提出地层压力、H_2S分压、H_2S含量、井深、地层温度、CL^-含量、p H值、气井地理位置、气井产量、井筒积液、建井年限、井口密封、井下工具性能、采气树性能、管柱密封性、腐蚀速率、环空内流体组分、环空压力与MOP、环空压力上升速率、泄压分析、固井质量等影响气井完整性的21项因素。利用层次分析法逐一进行分级、评分、权重调整,建立了气井风险等级判别模式,把气井的风险等级由低到高分为3类,Ⅰ类井正常生产,Ⅱ类井密切关注,Ⅲ类井需立即采取紧急处理措施。在生产过程中可通过对单井进行定期分析评价,及时掌握气井完整性的变化情况,保证气井安全、稳定生产。Gas wells with sustained annular pressure is a common issue in Yuanba gas field ,which lead to serious threats to the safety of gas well production.It is needed to give integrity evaluation and determine the level of risk,and then put forward the countermeasures.Based on the reasons analysis of sustained annular pressure and field experience of Yuanba gas field ,21 parameters that affect the integrity of the gas wells are proposed.It includes formation pressure,H2S partial pressure,H2S content,well depth,formation temperature,C1^- content, pH value, gas well location, gas well production, liquid loading, well age, well head sealing, downhole tool performance,performance of gas tree,string sealing,corrosion rate,fluid composition in annulus,sustained annular pressure and MOP,rise rate of annular pressure ,pressure-releasing analysis ,cementing quality.The in- fluence of each parameter is classified ,scored and adjusted on weight respectively by analytic hierarchy pro- cess.Risk level evaluation model for the gas well is established.According to the model,the gas well can be divided into three categories from low risk to high risk ：the wells of type I can be produced normally,the wells of type Ⅱ should be paid more attention ,and the wells of type m need to take emergency measure immediately.Single well should be analyzed and evaluated regularly during the production.And the change of the integrity of the gas wells can be known in time and safe and stable production of gas wells can be en- sured.

关 键 词：元坝气田 高含硫气井 环空带压 井筒完整性评价 风险级别判别模式 

分 类 号：TE38[石油与天然气工程—油气田开发工程]