基于模糊数学的防气窜能力评价新方法及应用
|
摘要
环空气窜现象是几乎所有天然气井固井存在的难题,危害十分严重,准确评价水泥浆防气窜能力是有效预防环空气窜现象的关键技术手段之一。固井环空气窜受多种因素综合影响,现有评价预测方法考虑因素较单一,准确度有限,缺乏更为全面综合的预判结果。结合环空气窜特点,采用模糊数学理论建立了水泥浆防气窜能力综合判断模型,以潜气窜因子法、水泥浆性能系数法等5种常用方法为评价因素集,以防气窜能力"好"、"中等"和"差"3种情况为评价集,结合各因素特点确定对应的隶属函数,采用层次分析法原理计算各因素权重模糊集,按"最大隶属原则"判断水泥浆防气窜能力评价结果。应用表明,该评价方法可有效预测固井气窜问题,为针对性地优化水泥浆体系,避免固井后井口带压,保证油气井固井质量和安全提供了更为全面、综合的评价方法。
Gas channeling in annular spaces is a difficult problem seriously harmful to cementing almost all gas wells. Accurate evaluation of cement slurry's anti-channeling performance is one of the key technologies for the prevention of gas channeling in annular spaces.There are several factors which affect gas channeling in annular spaces in a combined way, while the evaluation methods presently in use do not take them all in consideration and have limited accuracy, and hence they cannot give a full view of the problem they are trying to reveal. In this study, fuzzy mathematics has been used in establishing a model used in predicting comprehensively the anti-channeling performance of a cement slurry. This model takes into account the characteristics of gas channeling in annular spaces.Five commonly used evaluation methods, such as GFP method and SPN method etc., are integrated into an evaluation factor set,"good","medium" and "poor" anti-channeling capacity are used as an evaluation set. Based on the characteristics of each factor, a corresponding membership function is determined. Use the principles of analytic hierarchy process, the weighted fuzzy set of each factor is calculated, and according to the "maximum subordination principle", the overall risk of sand production is determined. It has been proved that this evaluation method can be used to effectively predict gas channeling in well cementing. It provides a more comprehensive and integrated evaluation method for optimizing cement slurry formulation to prevent pressurized wellhead after well cementing,thereby to ensure the quality and safety of a cemented well.
Gas channeling in annular spaces is a difficult problem seriously harmful to cementing almost all gas wells. Accurate evaluation of cement slurry's anti-channeling performance is one of the key technologies for the prevention of gas channeling in annular spaces.There are several factors which affect gas channeling in annular spaces in a combined way, while the evaluation methods presently in use do not take them all in consideration and have limited accuracy, and hence they cannot give a full view of the problem they are trying to reveal. In this study, fuzzy mathematics has been used in establishing a model used in predicting comprehensively the anti-channeling performance of a cement slurry. This model takes into account the characteristics of gas channeling in annular spaces.Five commonly used evaluation methods, such as GFP method and SPN method etc., are integrated into an evaluation factor set,"good","medium" and "poor" anti-channeling capacity are used as an evaluation set. Based on the characteristics of each factor, a corresponding membership function is determined. Use the principles of analytic hierarchy process, the weighted fuzzy set of each factor is calculated, and according to the "maximum subordination principle", the overall risk of sand production is determined. It has been proved that this evaluation method can be used to effectively predict gas channeling in well cementing. It provides a more comprehensive and integrated evaluation method for optimizing cement slurry formulation to prevent pressurized wellhead after well cementing,thereby to ensure the quality and safety of a cemented well.
引文
[1]刘崇建,谢应权,郭小阳,等.水泥浆凝固过程的气窜问题[J].西南石油学院学报,1998,20(4):47-52.LIU Chongjian,XIE Yingquan,GUO Xiaoyang,et al.The gas migration during cement setting process[J].Journal of Southwest Petroleum Institute,1998,20(4):47-52.
[2]RAE P,WILKINS D,FREE D A.New approach to the prediction of gas flow after cementing[C].paper 18622-MS presented at the SPE/IADC Drilling Conference,28February-3 March,New Orleans,Louisiana,USA.New York:SPE,1989:61-69.
[3]CHEUNG P R,ROBERT M.Gas Flow in Cements[J].Journal of Petroleum Technology,June 1985:1041-1048.
[4]SYKES R L,LOGAN J L.New technology in gas migration control[C].paper 16653-MS presented at the SPE Annual Technical Conference and Exhibition,27-30September,Dallas,USA.New York:SPE,1987:43-48.
[5]丁士东.固井后环空气窜预测方法[J].钻井液与完井液,2003,20(6):30-33.DING Shidong.The prediction method of gas channeling after cementing[J].Drilling Fluid and Completion Fluid,2003,20(6):30-33.
[6]李进.基于胶凝态水泥浆性能的防气窜能力评价方法研究[D].成都:西南石油大学,2015.LI Jin.Study on the new prediction of gas migration based on the gelling surry performance[D].Chengdu:Southwest Petroleum University,2015.
[7]李早元,李进,郭小阳,等.固井早期气窜预测新方法研究[J].天然气工业,2014,34(10):75-82.LI Zaoyuan,LI Jin,GUO Xiaoyang,et al.A new method of predicting gas channeling at the early stage of cementing[J].Natural Gas Industry,2014,34(10):75-82.
[8]张晨,刘万宏,王立义,等.模糊数学在水库水质综合评价中的应用[J].安全与环境学报,2009,9(1):90-92.ZHANG Chen,LIU Wanghong,WANG Liyi,et al.Application of fuzzy mathematical analysis in the evaluation of water environment[J].Hydrology,2009,9(1):90-92.
[9]张建江,党荣理,马永红,等.中国边境地区西北段饮用水质量的模糊数学评价[J].中国卫生检验杂志,2014,24(1):100-102.ZHANG Jianjiang,DANG Rongli,MA Yonghong,et al.Fuzzy mathematics evalution of drinking water quality in northwest border of china[J].Chin J Health Lab Tec,2009,9(1):90-92.
[10]崔振华,徐秀芬,董世民.模糊数学在机采方式优选中的应用[J].石油学报,1995,16(1):105-110.CUI Zhenhua,XU Xiufen,DONG Shimin.The optimum application of fuzzy mathematics in artificial lift[J].Acta Petrolei Sinica,1995,16(1):105-110.
[11]郭长春,金强,姚军.用模糊数学方法评价烃源岩[J].石油学报,2005,26(4):50-53.GUO Changchun,JIN Qiang,YAO Jun.Evaluation of source rocks with fuzzy mathematics[J].Acta Petrolei Sinica,2005,26(4):50-53.
[12]谢季坚,刘承平.模糊数学方法及其应用[M].武汉:华中科技大学出版社,2006.XIE Jijian,LIU Chenping.Fuzzy mathematics method and its application[M].Wuhan:Huazhong University of Science and Technology Press,2006.
[13]SABINS F L,SUTTON D L.Interrelationship between critical cement properties and volume changes during cement setting[J].SPE Drilling Engineering,1991,6(2):88-94.
[14]宋国民,翟羽健,刘星荣.一种确定模糊综合评判权重集方法的探讨[J].模糊系统与数学,2000,14:299-302.SONG Guomin,ZHAI Yujian,LIU Xingrong.Discussing of a new method to determine the weight assembly of fuzzy comprehensive evalution[J].Fuzzy Systems and Mathematics,2000,14:299-302.
[15]唐国强.基于模糊数学的深水完井方法优选研究与应用[D].西南石油大学,2015.TANG Guoqiang.Study on the new method to optimization the deepwater-well completion method based on the fuzzy mathematics[D].Southwest Petroleum University,2015.
[16]涂道兴,张光裕.线性代数[M].北京:高等教育出版社,2008.TU Daoxing,ZHANG Guangyu.Linear algebra[M].Beijing:Higher Education Press,2008.
[2]RAE P,WILKINS D,FREE D A.New approach to the prediction of gas flow after cementing[C].paper 18622-MS presented at the SPE/IADC Drilling Conference,28February-3 March,New Orleans,Louisiana,USA.New York:SPE,1989:61-69.
[3]CHEUNG P R,ROBERT M.Gas Flow in Cements[J].Journal of Petroleum Technology,June 1985:1041-1048.
[4]SYKES R L,LOGAN J L.New technology in gas migration control[C].paper 16653-MS presented at the SPE Annual Technical Conference and Exhibition,27-30September,Dallas,USA.New York:SPE,1987:43-48.
[5]丁士东.固井后环空气窜预测方法[J].钻井液与完井液,2003,20(6):30-33.DING Shidong.The prediction method of gas channeling after cementing[J].Drilling Fluid and Completion Fluid,2003,20(6):30-33.
[6]李进.基于胶凝态水泥浆性能的防气窜能力评价方法研究[D].成都:西南石油大学,2015.LI Jin.Study on the new prediction of gas migration based on the gelling surry performance[D].Chengdu:Southwest Petroleum University,2015.
[7]李早元,李进,郭小阳,等.固井早期气窜预测新方法研究[J].天然气工业,2014,34(10):75-82.LI Zaoyuan,LI Jin,GUO Xiaoyang,et al.A new method of predicting gas channeling at the early stage of cementing[J].Natural Gas Industry,2014,34(10):75-82.
[8]张晨,刘万宏,王立义,等.模糊数学在水库水质综合评价中的应用[J].安全与环境学报,2009,9(1):90-92.ZHANG Chen,LIU Wanghong,WANG Liyi,et al.Application of fuzzy mathematical analysis in the evaluation of water environment[J].Hydrology,2009,9(1):90-92.
[9]张建江,党荣理,马永红,等.中国边境地区西北段饮用水质量的模糊数学评价[J].中国卫生检验杂志,2014,24(1):100-102.ZHANG Jianjiang,DANG Rongli,MA Yonghong,et al.Fuzzy mathematics evalution of drinking water quality in northwest border of china[J].Chin J Health Lab Tec,2009,9(1):90-92.
[10]崔振华,徐秀芬,董世民.模糊数学在机采方式优选中的应用[J].石油学报,1995,16(1):105-110.CUI Zhenhua,XU Xiufen,DONG Shimin.The optimum application of fuzzy mathematics in artificial lift[J].Acta Petrolei Sinica,1995,16(1):105-110.
[11]郭长春,金强,姚军.用模糊数学方法评价烃源岩[J].石油学报,2005,26(4):50-53.GUO Changchun,JIN Qiang,YAO Jun.Evaluation of source rocks with fuzzy mathematics[J].Acta Petrolei Sinica,2005,26(4):50-53.
[12]谢季坚,刘承平.模糊数学方法及其应用[M].武汉:华中科技大学出版社,2006.XIE Jijian,LIU Chenping.Fuzzy mathematics method and its application[M].Wuhan:Huazhong University of Science and Technology Press,2006.
[13]SABINS F L,SUTTON D L.Interrelationship between critical cement properties and volume changes during cement setting[J].SPE Drilling Engineering,1991,6(2):88-94.
[14]宋国民,翟羽健,刘星荣.一种确定模糊综合评判权重集方法的探讨[J].模糊系统与数学,2000,14:299-302.SONG Guomin,ZHAI Yujian,LIU Xingrong.Discussing of a new method to determine the weight assembly of fuzzy comprehensive evalution[J].Fuzzy Systems and Mathematics,2000,14:299-302.
[15]唐国强.基于模糊数学的深水完井方法优选研究与应用[D].西南石油大学,2015.TANG Guoqiang.Study on the new method to optimization the deepwater-well completion method based on the fuzzy mathematics[D].Southwest Petroleum University,2015.
[16]涂道兴,张光裕.线性代数[M].北京:高等教育出版社,2008.TU Daoxing,ZHANG Guangyu.Linear algebra[M].Beijing:Higher Education Press,2008.