深水油气井关井期间井筒含天然气水合物相变的气泡上升规律研究
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摘要
深水油气井关井期间天然气水合物的生成会导致气泡迁移滞后,影响钻井安全作业周期,为此利用室内垂直圆筒模拟深水井筒环境,实验研究了甲烷气泡表面水合物膜生长特性,提出了考虑自然对流传热的水合物横向生长模型及水合物膜厚度预测方法;分析了水合物气泡变形率与莫顿数、拖曳力系数及雷诺数之间的相关性,据此建立了关井条件下井筒中含水合物相变的气泡上升速度综合预测模型,并对南海某井的安全作业周期进行了预测和分析。通过实验和模拟分析发现,建立的自然对流传热模型对水合物膜横向生长速率和厚度具有较高的预测精度;水合物气泡的变形率随莫顿数增大而减小,拖曳力系数随雷诺数增大先减小然后逐渐增大,并拟合得到了气泡变形率、拖曳力系数计算公式。研究表明,气泡表面水合物的生成显著降低了气泡的上升速度,延长了安全作业周期,但气体到达海底井口后水合物堵塞风险增加,现场应根据关井时间采取针对性的井控措施。
During the shut-in of deepwater wells, the formation of natural gas hydrate will significantly delay the migration of bubbles and affect the safe operation cycle of drilling. The bubble ascending dynamics considering the phase change of hydrate was studied. In the study, an indoor vertical cylinder was used to simulate the deepwater wellbore and to investigate the growth characteristics of hydrate film on the surface of methane bubbles.. A model was proposed which incorporated the hydrate lateral growth model and the hydrate film thickness prediction method considering natural convection heat transfer. The correlations between hydrate bubble deformation rate and Morton number, drag coefficient and Reynolds number were explored. A comprehensive prediction model of bubble ascending velocity in wellbore considering hydrate phase change under shut-in conditions was established based on the study, and the safe operation cycle of a well in the South China Sea was predicted and analyzed. The experimental and simulation results show that the newly established natural convection heat transfer model has higher prediction accuracy for the lateral growth rate and thickness of the hydrate film and that the deformation rate of hydrate bubble decreases with the Morton number. The drag coefficient decreases first and then increases gradually with the Reynolds number and the corresponding calculation formula was obtained through fitting. Studies suggest that the formation of hydrate on the surface of the bubbles can significantly reduce the ascending velocity of bubbles and prolong the safe operation cycle.However, the risk of hydrate blockage will increase as gas reaches the subsea wellhead, and pertinent well control measures should be taken according to the shut-in time.
During the shut-in of deepwater wells, the formation of natural gas hydrate will significantly delay the migration of bubbles and affect the safe operation cycle of drilling. The bubble ascending dynamics considering the phase change of hydrate was studied. In the study, an indoor vertical cylinder was used to simulate the deepwater wellbore and to investigate the growth characteristics of hydrate film on the surface of methane bubbles.. A model was proposed which incorporated the hydrate lateral growth model and the hydrate film thickness prediction method considering natural convection heat transfer. The correlations between hydrate bubble deformation rate and Morton number, drag coefficient and Reynolds number were explored. A comprehensive prediction model of bubble ascending velocity in wellbore considering hydrate phase change under shut-in conditions was established based on the study, and the safe operation cycle of a well in the South China Sea was predicted and analyzed. The experimental and simulation results show that the newly established natural convection heat transfer model has higher prediction accuracy for the lateral growth rate and thickness of the hydrate film and that the deformation rate of hydrate bubble decreases with the Morton number. The drag coefficient decreases first and then increases gradually with the Reynolds number and the corresponding calculation formula was obtained through fitting. Studies suggest that the formation of hydrate on the surface of the bubbles can significantly reduce the ascending velocity of bubbles and prolong the safe operation cycle.However, the risk of hydrate blockage will increase as gas reaches the subsea wellhead, and pertinent well control measures should be taken according to the shut-in time.
引文
[1]谢仁军,刘书杰,文敏,等.深水钻井溢流井控期间水合物生成主控因素[J].石油钻采工艺,2015,37(1):64-67.XIE Renjun,LIU Shujie,WEN Min,et al.Main control factor of hydrate generation during overflow well control period of deepwater drilling[J].Oil Drilling&Production Technology,2015,37(1):64-67.
[2]王金波,王志远,张伟国,等.南海深水海域避台风期间井控安全作业周期研究[J].石油钻探技术,2013,41(3):51-55.WANG Jinbo,WANG Zhiyuan,ZHANG Weiguo,et al.Well control safety operation cycle during typhoon at deep waters of South China Sea[J].Petroleum Drilling Techniques,2013,41(3):51-55.
[3]叶鹏,刘道平,张健.悬浮气泡表面天然气水合物形成的特性研究[J].石油与天然气化工,2013,42(5):468-472.YE Peng,LIU Daoping,ZHANG Jian.Characteristics researches of natural gas hydrate growth on the suspended bubble surface[J].Chemical Engineering of Oil&Gas,2013,42(5):468-472.
[4]张健,刘道平,苏星,等.水滴和气泡表面气体水合物的生长特性对比[J].石油与天然气化工,2013,42(1):37-41.ZHANG Jian,LIU Daoping,SU Xing,et al.Comparative analysis of growth characteristics of hydrate formation on the surface of suspended water droplet and bubble[J].Chemical Engineering of Oil&Gas,2013,42(1):37-41.
[5]蔡婷.天然气水合物在管道中沉积与崩塌的预测模型研究[J].钻采工艺,2018,41(6):46-49.CAI Ting.Model for predicting deposition and collapse of natural gas hydrate in pipeline[J].Drilling&Production Technology,2018,41(6):46-49.
[6]LIU Zheng,LI Hao,CHEN Litao,et al.A new model of and insight into hydrate film lateral growth along the gas-liquid interface considering natural convection heat transfer[J].Energy&Fuels,2018,32(2):2053-2063.
[7]BATCHELOR G K.An introduction to fluid dynamics[M].Cambridge:Cambridge University Press,2000:211-219.
[8]DAVIES R M,TAYLOR G I.The mechanics of large bubbles rising through extended liquids and through liquids in tubes[J].Proceedings of the Royal Society A,1950,200(1062):375-390.
[9]WALLIS G B.The terminal speed of single drops or bubbles in an infinite medium[J].International Journal of Multiphase Flow,1974,1(4):491-511.
[10]闫红杰,赵国建,刘柳,等.静止水中单气泡形状及上升规律的实验研究[J].中南大学学报(自然科学版),2016,47(7):2513-2520.YAN Hongjie,ZHAO Guojian,LIU Liu,et al.Experimental study on shape and rising behavior of single bubble in stagnant water[J].Journal of Central South University(Science and Technology),2016,47(7):2513-2520.
[11]BIGALKE N K,ENSTAD L I,REHDER G,et al.Terminal velocities of pure and hydrate coated CO2 droplets and CH4 bubbles rising in a simulated oceanic environment[J].Deep Sea Research PartⅠ:Oceanographic Research Papers,2010,57(9):1102-1110.
[12]SATO Y,KIYONO F,OGASAWARA K,et al.An experimental study on the dynamics of a rising methane bubble covered with hydrates[J].Journal of the Mining and Materials Processing Institute of Japan,2013,129(4):124-131.
[13]FISHENDEN M W,SAUNDERS O A.An introduction to heat transfer[M].Oxford:Clarendon Press,1950:136-138.
[14]LEWANDOWSKI W M,RADZIEMSKA E,BUZUK M,et al.Free convection heat transfer and fluid flow above horizontal rectangular plates[J].Applied Energy,2000,66(2):177-197.
[15]SAVILLE D A,CHURCHILL S W.Laminar free convection in boundary layers near horizontal cylinders and vertical axisymmetric bodies[J].Journal of Fluid Mechanics,1967,29(2):391-399.
[16]PENG B Z,DANDEKAR A,SUN Changyu,et al.Hydrate film growth on the surface of a gas bubble suspended in water[J].The Journal of Physical Chemistry B,2007,111(43):12485-12493.
[17]WILKINSON P M,HARINGA H,VAN DIERENDONCK L L.Mass transfer and bubble size in a bubble column under pressure[J].Chemical Engineering Science,1994,49(9):1417-1427.
[18]UCHIDA T,EBINUMA T,KAWABATA J,et al.Microscopic observations of formation processes of clathrate-hydrate films at an interface between water and carbon dioxide[J].Journal of Crystal Growth,1999,204(3):348-356.
[19]MORI Y H.Estimating the thickness of hydrate films from their lateral growth rates:application of a simplified heat transfer model[J].Journal of Crystal Growth,2001,223(1/2):206-212.
[20]FREER E M,SELIM M S,SLOAN E D Jr.Methane hydrate film growth kinetics[J].Fluid Phase Equilibria,2001,185(1/2):65-75.
[21]MOCHIZUKI T,MORI Y H.Clathrate-hydrate film growth along water/hydrate-former phase boundaries-numerical heat-transfer study[J].Journal of Crystal Growth,2006,290(2):642-652.
[22]LI Shengli,SUN Changyu,LIU Bei,et al.Initial thickness measurements and insights into crystal growth of methane hydrate film[J].AIChE Journal,2013,59(6):2145-2154.
[2]王金波,王志远,张伟国,等.南海深水海域避台风期间井控安全作业周期研究[J].石油钻探技术,2013,41(3):51-55.WANG Jinbo,WANG Zhiyuan,ZHANG Weiguo,et al.Well control safety operation cycle during typhoon at deep waters of South China Sea[J].Petroleum Drilling Techniques,2013,41(3):51-55.
[3]叶鹏,刘道平,张健.悬浮气泡表面天然气水合物形成的特性研究[J].石油与天然气化工,2013,42(5):468-472.YE Peng,LIU Daoping,ZHANG Jian.Characteristics researches of natural gas hydrate growth on the suspended bubble surface[J].Chemical Engineering of Oil&Gas,2013,42(5):468-472.
[4]张健,刘道平,苏星,等.水滴和气泡表面气体水合物的生长特性对比[J].石油与天然气化工,2013,42(1):37-41.ZHANG Jian,LIU Daoping,SU Xing,et al.Comparative analysis of growth characteristics of hydrate formation on the surface of suspended water droplet and bubble[J].Chemical Engineering of Oil&Gas,2013,42(1):37-41.
[5]蔡婷.天然气水合物在管道中沉积与崩塌的预测模型研究[J].钻采工艺,2018,41(6):46-49.CAI Ting.Model for predicting deposition and collapse of natural gas hydrate in pipeline[J].Drilling&Production Technology,2018,41(6):46-49.
[6]LIU Zheng,LI Hao,CHEN Litao,et al.A new model of and insight into hydrate film lateral growth along the gas-liquid interface considering natural convection heat transfer[J].Energy&Fuels,2018,32(2):2053-2063.
[7]BATCHELOR G K.An introduction to fluid dynamics[M].Cambridge:Cambridge University Press,2000:211-219.
[8]DAVIES R M,TAYLOR G I.The mechanics of large bubbles rising through extended liquids and through liquids in tubes[J].Proceedings of the Royal Society A,1950,200(1062):375-390.
[9]WALLIS G B.The terminal speed of single drops or bubbles in an infinite medium[J].International Journal of Multiphase Flow,1974,1(4):491-511.
[10]闫红杰,赵国建,刘柳,等.静止水中单气泡形状及上升规律的实验研究[J].中南大学学报(自然科学版),2016,47(7):2513-2520.YAN Hongjie,ZHAO Guojian,LIU Liu,et al.Experimental study on shape and rising behavior of single bubble in stagnant water[J].Journal of Central South University(Science and Technology),2016,47(7):2513-2520.
[11]BIGALKE N K,ENSTAD L I,REHDER G,et al.Terminal velocities of pure and hydrate coated CO2 droplets and CH4 bubbles rising in a simulated oceanic environment[J].Deep Sea Research PartⅠ:Oceanographic Research Papers,2010,57(9):1102-1110.
[12]SATO Y,KIYONO F,OGASAWARA K,et al.An experimental study on the dynamics of a rising methane bubble covered with hydrates[J].Journal of the Mining and Materials Processing Institute of Japan,2013,129(4):124-131.
[13]FISHENDEN M W,SAUNDERS O A.An introduction to heat transfer[M].Oxford:Clarendon Press,1950:136-138.
[14]LEWANDOWSKI W M,RADZIEMSKA E,BUZUK M,et al.Free convection heat transfer and fluid flow above horizontal rectangular plates[J].Applied Energy,2000,66(2):177-197.
[15]SAVILLE D A,CHURCHILL S W.Laminar free convection in boundary layers near horizontal cylinders and vertical axisymmetric bodies[J].Journal of Fluid Mechanics,1967,29(2):391-399.
[16]PENG B Z,DANDEKAR A,SUN Changyu,et al.Hydrate film growth on the surface of a gas bubble suspended in water[J].The Journal of Physical Chemistry B,2007,111(43):12485-12493.
[17]WILKINSON P M,HARINGA H,VAN DIERENDONCK L L.Mass transfer and bubble size in a bubble column under pressure[J].Chemical Engineering Science,1994,49(9):1417-1427.
[18]UCHIDA T,EBINUMA T,KAWABATA J,et al.Microscopic observations of formation processes of clathrate-hydrate films at an interface between water and carbon dioxide[J].Journal of Crystal Growth,1999,204(3):348-356.
[19]MORI Y H.Estimating the thickness of hydrate films from their lateral growth rates:application of a simplified heat transfer model[J].Journal of Crystal Growth,2001,223(1/2):206-212.
[20]FREER E M,SELIM M S,SLOAN E D Jr.Methane hydrate film growth kinetics[J].Fluid Phase Equilibria,2001,185(1/2):65-75.
[21]MOCHIZUKI T,MORI Y H.Clathrate-hydrate film growth along water/hydrate-former phase boundaries-numerical heat-transfer study[J].Journal of Crystal Growth,2006,290(2):642-652.
[22]LI Shengli,SUN Changyu,LIU Bei,et al.Initial thickness measurements and insights into crystal growth of methane hydrate film[J].AIChE Journal,2013,59(6):2145-2154.