天然气水合物在水力提升管道中的分解特性
|
摘要
为了指导海底天然气水合物(以下简称水合物)绞吸式开采水力提升管道系统参数设置,研究了水力提升管道内水合物的分解特性和流动参数变化对其的影响。基于热力学和流体力学,采用数学建模的方式建立了水合物水力提升管道温压模型、水合物分解传质模型和管道多相流模型,分析了固液两相流转变成固液气三相流过程中不同影响因素下管道流体温压、水合物颗粒物质的量、分解面位置与海水深度的关系。结果表明:(1)随着管道流量增大,水合物分解速度减慢,分解面少量上移;(2)颗粒直径对管流温压、相平衡压力、水合物分解面基本没有影响,但只有直径小于0.2 mm的水合物颗粒才能在管道中完全分解,直径大于2.0 mm后,颗粒分解量忽略不计;(3)出口回压为正压且增加时,水合物分解面上移,分解速度减慢,而出口回压为负压且增大时,水合物分解面下移,分解速度加快;(4)随着采矿深度的增加,水合物分解速度变慢,分解面上移,但在与海面距离超过1 500 m后采矿深度对水合物分解速度、分解面无影响;(5)实验验证与数值仿真规律基本一致,表明所建立的模型具有较高的可信度。结论认为:绞吸式开采水合物时,控制合理的流量和出口回压能够调节分解面高度以及分解速度,并且不用考虑颗粒直径和采矿深度对产气量的影响。
For the sake of guiding parameter setting of the hydraulic lifting pipeline system for cutter-suction mining of natural gas hydrates in sea beds(hereinafter, hydrates for short), the decomposition characteristics of hydrates in hydraulic lifting pipelines and the effects of flow parameters on decomposition characteristics were studied in this paper. A temperature–pressure model for the hydrate hydraulic lifting pipeline, a hydrate decomposition mass transfer model and a pipeline multi-phase flow model were established using mathematical modeling method according to thermodynamics and fluid mechanics. Then, the relationships of the temperature and pressure of pipeline fluid, the amount of hydrate particulate matter and the decomposition surface vs. the seawater depth under the effect of different influencing factors during the transformation from solid–liquid two-phase flow to solid–liquid–gas three-phase flow were analyzed. And the following research results were obtained. First, the decomposition of hydrate slows down and the decomposition surface moves upward slightly with the increase of flow rate in the pipeline. Second, particle size basically has no effects on the temperature and pressure of pipeline fluid, the phase equilibrium pressure and hydrate decomposition surface. However, only the hydrate particles whose diameter is smaller than 0.2 mm can be completely decomposed in the pipeline while the decomposition of those whose particles size is greater than 2.0 mm is negligible. Third, if the back pressure at the outlet is positive, the decomposition surface moves upward and the decomposition of hydrate slows down with the increase of the back pressure. And if the back pressure at the outlet is negative, the decomposition surface moves downward and the decomposition of hydrate speeds up with the increase of the back pressure. Fourth, the decomposition of hydrate slows down and the decomposition surface moves upward with the increase of mining depth. However, the decomposition velocity and decomposition surface are basically unchanged when the mining depth is below 1 500 m under water. Fifth, the experimental results are basically consistent with the numerical simulation results, and it is indicated that the newly established models are of high reliability. In conclusion, decomposition surface height and decomposition velocity can be adjusted by controlling flow rate and outlet back pressure rationally during the cutter-suction mining of hydrates while the influences of particle diameter and mining depth on gas production rate need not be taken into consideration.
For the sake of guiding parameter setting of the hydraulic lifting pipeline system for cutter-suction mining of natural gas hydrates in sea beds(hereinafter, hydrates for short), the decomposition characteristics of hydrates in hydraulic lifting pipelines and the effects of flow parameters on decomposition characteristics were studied in this paper. A temperature–pressure model for the hydrate hydraulic lifting pipeline, a hydrate decomposition mass transfer model and a pipeline multi-phase flow model were established using mathematical modeling method according to thermodynamics and fluid mechanics. Then, the relationships of the temperature and pressure of pipeline fluid, the amount of hydrate particulate matter and the decomposition surface vs. the seawater depth under the effect of different influencing factors during the transformation from solid–liquid two-phase flow to solid–liquid–gas three-phase flow were analyzed. And the following research results were obtained. First, the decomposition of hydrate slows down and the decomposition surface moves upward slightly with the increase of flow rate in the pipeline. Second, particle size basically has no effects on the temperature and pressure of pipeline fluid, the phase equilibrium pressure and hydrate decomposition surface. However, only the hydrate particles whose diameter is smaller than 0.2 mm can be completely decomposed in the pipeline while the decomposition of those whose particles size is greater than 2.0 mm is negligible. Third, if the back pressure at the outlet is positive, the decomposition surface moves upward and the decomposition of hydrate slows down with the increase of the back pressure. And if the back pressure at the outlet is negative, the decomposition surface moves downward and the decomposition of hydrate speeds up with the increase of the back pressure. Fourth, the decomposition of hydrate slows down and the decomposition surface moves upward with the increase of mining depth. However, the decomposition velocity and decomposition surface are basically unchanged when the mining depth is below 1 500 m under water. Fifth, the experimental results are basically consistent with the numerical simulation results, and it is indicated that the newly established models are of high reliability. In conclusion, decomposition surface height and decomposition velocity can be adjusted by controlling flow rate and outlet back pressure rationally during the cutter-suction mining of hydrates while the influences of particle diameter and mining depth on gas production rate need not be taken into consideration.
引文
[1]《广东造船》编辑部.我国首次在南海发现裸露“可燃冰”[J].广东造船,2017,36(5):99.Editorial Department of Guangdong Shipbuilding.The bare"combustible ice"was first found in South China Sea[J].Guangdong Shipbuilding,2017,36(5):99.
[2]Sia?ik J&Malcho M.Accumulation of primary energy into natural gas hydrates[J].Procedia Engineering,2017,192:782-787.
[3]Song Yongchen,Yang Lei,Zhao Jiafei,Liu Weiguo,Yang Mingjun,Li Yanghui,et al.The status of natural gas hydrate research in China:A review[J].Renewable&Sustainable Energy Reviews,2014,31(2):778-791.
[4]Xu Chugang,Cai Jing,Lin Fuhua,Chen Zhaoyang&Li Xiaosen.Raman analysis on methane production from natural gas hydrate by carbon dioxide-methane replacement[J].Energy,2015,79(19):111-116.DOI:https://doi.org/10.1016/j.energy.2014.10.068
[5]周守为,陈伟,李清平,周建良,施和生.深水浅层非成岩天然气水合物固态流化试采技术研究及进展[J].中国海上油气,2017,29(4):1-8.Zhou Shouwei,Chen Wei,Li Qingping,Zhou Jianliang&Shi Hesheng.Research on the solid fluidization well testing and production for shallow non-diagenetic natural gas hydrate in deep water area[J].China Offshore Oil and Gas,2017,29(4):1-8.
[6]徐海良,杨放琼,吴波,郑义,陈旺.一种海底天然气水合物绞吸式开采方法:中国,201510568442.0[P].2017-3-22.Xu Hailiang,Yang Fangqiong,Wu Bo,Zheng Yi&Chen Wang.A submarine gas hydrate cutter suction mining method:China,201510568442.0[P].2017-3-22.
[7]Li Li,Xu Hailiang&Yang Fangqiong.Three-phase flow of submarine gas hydrate pipe transport[J].Journal of Central South University,2015,22:3650-3656.
[8]徐海良,谢秋敏,吴波,赵海鸣,徐绍军.天然气水合物开采管道水力提升数值仿真分析[J].中南大学学报(自然科学版),2015,46(11):4062-4069.Xu Hailiang,Xie Qiumin,Wu Bo,Zhao Haiming&Xu Shaojun.Numerical simulation and analysis of gas hydrate mining pipe hydraulic lifting[J].Journal of Central South University(Science and Technology),2015,46(11):4062-4069.
[9]徐海良,林良程,吴万荣,吴波.海底天然气水合物绞吸式开采方法研究[J].中山大学学报(自然科学版),2011,50(3):48-52.Xu Hailiang,Lin Liangcheng,Wu Wanrong&Wu Bo.Cutter-suction exploitation mode of marine gas hydrate[J].Acta Scientiarum Naturalium Universitatis Sunyatseni,2011,50(3):48-52.
[10]周守为,赵金洲,李清平,陈伟,周建良,魏纳,等.全球首次海洋天然气水合物固态流化试采工程参数优化设计[J].天然气工业,2017,37(9):1-14.Zhou Shouwei,Zhao Jinzhou,Li Qingping,Chen Wei,Zhou Jianliang,Wei Na,et al.Optimal design of the engineering parameters for the first global trial production of marine natural gas hydrates through solid fluidization[J].Natural Gas Industry,2017,37(9):1-14.
[11]赵金洲,周守为,张烈辉,伍开松,郭平,李清平,等.世界首个海洋天然气水合物固态流化开采大型物理模拟实验系统[J].天然气工业,2017,37(9):15-22.Zhao Jinzhou,Zhou Shouwei,Zhang Liehui,Wu Kaisong,Guo Ping,Li Qingping,et al.The first global physical simulation experimental systems for the exploitation of marine natural gas hydrates through solid fluidization[J].Natural Gas Industry,2017,37(9):15-22.
[12]魏纳,孙万通,孟英峰,周守为,付强,郭平,等.海洋天然气水合物藏钻探环空相态特性[J].石油学报,2017,38(6):710-720.Wei Na,Sun Wantong,Meng Yingfeng,Zhou Shouwei,Fu Qiang,Guo Ping,et al.Annular phase behavior analysis during marine natural gas hydrate reservoir drilling[J].Acta Petrolei Sinica,2017,38(6):710-720.
[13]高永海,孙宝江,赵欣欣,王志远,殷志明,王金波.水合物钻探井筒多相流动及井底压力变化规律[J].石油学报,2012,33(5):881-886.Gao Yonghai,Sun Baojiang,Zhao Xinxin,Wang Zhiyuan,Yin Zhiming&Wang Jinbo.Multiphase flow in wellbores and variation laws of the bottom hole pressure in gas hydrate drilling[J].Acta Petrolei Sinica,2012,33(5):881-886.
[14]Padsalgikar A.Particle transport in stratified gas-liquid-solid flow[D].Tulsa:The University of Tulsa,2015.
[15]刘建军,邵祖亮,郑永香.天然气水合物降压分解过程的数值模拟[J].西南石油大学学报(自然科学版),2017,39(1):80-90.Liu Jianjun,Shao Zuliang&Zheng Yongxiang.Numberical simulation of the decomposition of natural gas hydrates by depressurization[J].Journal of Southwest Petroleum University(Science&Technology Edition),2017,39(1):80-90.
[16]周守为,李清平,陈伟,付强.天然气水合物开采三维实验模拟技术研究[J].中国海上油气,2016,28(4):1-9.Zhou Shouwei,Li Qingping,Chen Wei&Fu Qiang.Research on3D experiment technology of natural gas hydrate exploitation[J].China Offshore Oil and Gas,2016,28(4):1-9.
[17]Jang CL,Shimizu Y&Lee GH.Numerical simulation of the fluvial processes in the channels by sediment mining[J].KSCEJournal of Civil Engineering,2015,19(3):771-778.
[18]Wang ZM,Hao XN,Wang XQ,Xue L&Guo XL.Numerical simulation on deepwater drilling wellbore temperature and pressure distribution[J].Petroleum Science and Technology,2010,28(9):911-919.
[19]赵金洲,彭瑀,李勇明,田植升,符东宇.基于双层非稳态导热过程的井筒温度场半解析模型[J].天然气工业,2016,36(1):68-75.Zhao Jinzhou,Peng Yu,Li Yongming,Tian Zhisheng&Fu Dongyu.A semi-analytic model of wellbore temperature field based on double-layer unsteady heat conducting process[J].Natural Gas Industry,2016,36(1):68-75.
[20]Xu Jingyu,Zhang Jian,Liu Haifei&Wu Yingxiang.Oil-gaswater three-phase upward flow through a vertical pipe:Influence of gas injection on the pressure gradient[J].International Journal of Multiphase Flow,2012,46:1-8.
[21]付建红,冯剑,陈平,韦红术,刘正礼.深水动态压井钻井井筒压力模拟[J].石油学报,2015,36(2):232-237.Fu Jianhong,Feng Jian,Chen Ping,Wei Hongshu&Liu Zhengli.Simulation on wellbore pressure during dynamic kill drilling in deep water[J].Acta Petrolei Sinica,2015,36(2):232-237.
[22]Dzyuba AV&Zektser IS.Variations in submarine groundwater runoff as a possible cause of decomposition of marine methane-hydrates in the Artcic[J].Water Resources,2013,40(1):74-83.
[23]Kim HC,Bishnoi PR,Heidemann RA&Rizvi SSH.Kinetics of methane hydrate decomposition[J].Chemical Engineering Science,1987,42(7):1645-1653.DOI:https://doi.org/10.1016/0009-2509(87)80169-0.
[24]Windmeier C&Oellrich LR.Theoretical study of gas hydrate decomposition kinetics:Model predictios[J].The Journal of Physical Chenistry,2013,117(47):12184-12195.
[25]Hamaguchi R,Nishimura Y,Inoue G,Matsukuma Y&Minemoto M.Gas hydrate decomposition rate in flowing water[J].Journal of Energy Resources Technology,2007,129(2):102-106.
[2]Sia?ik J&Malcho M.Accumulation of primary energy into natural gas hydrates[J].Procedia Engineering,2017,192:782-787.
[3]Song Yongchen,Yang Lei,Zhao Jiafei,Liu Weiguo,Yang Mingjun,Li Yanghui,et al.The status of natural gas hydrate research in China:A review[J].Renewable&Sustainable Energy Reviews,2014,31(2):778-791.
[4]Xu Chugang,Cai Jing,Lin Fuhua,Chen Zhaoyang&Li Xiaosen.Raman analysis on methane production from natural gas hydrate by carbon dioxide-methane replacement[J].Energy,2015,79(19):111-116.DOI:https://doi.org/10.1016/j.energy.2014.10.068
[5]周守为,陈伟,李清平,周建良,施和生.深水浅层非成岩天然气水合物固态流化试采技术研究及进展[J].中国海上油气,2017,29(4):1-8.Zhou Shouwei,Chen Wei,Li Qingping,Zhou Jianliang&Shi Hesheng.Research on the solid fluidization well testing and production for shallow non-diagenetic natural gas hydrate in deep water area[J].China Offshore Oil and Gas,2017,29(4):1-8.
[6]徐海良,杨放琼,吴波,郑义,陈旺.一种海底天然气水合物绞吸式开采方法:中国,201510568442.0[P].2017-3-22.Xu Hailiang,Yang Fangqiong,Wu Bo,Zheng Yi&Chen Wang.A submarine gas hydrate cutter suction mining method:China,201510568442.0[P].2017-3-22.
[7]Li Li,Xu Hailiang&Yang Fangqiong.Three-phase flow of submarine gas hydrate pipe transport[J].Journal of Central South University,2015,22:3650-3656.
[8]徐海良,谢秋敏,吴波,赵海鸣,徐绍军.天然气水合物开采管道水力提升数值仿真分析[J].中南大学学报(自然科学版),2015,46(11):4062-4069.Xu Hailiang,Xie Qiumin,Wu Bo,Zhao Haiming&Xu Shaojun.Numerical simulation and analysis of gas hydrate mining pipe hydraulic lifting[J].Journal of Central South University(Science and Technology),2015,46(11):4062-4069.
[9]徐海良,林良程,吴万荣,吴波.海底天然气水合物绞吸式开采方法研究[J].中山大学学报(自然科学版),2011,50(3):48-52.Xu Hailiang,Lin Liangcheng,Wu Wanrong&Wu Bo.Cutter-suction exploitation mode of marine gas hydrate[J].Acta Scientiarum Naturalium Universitatis Sunyatseni,2011,50(3):48-52.
[10]周守为,赵金洲,李清平,陈伟,周建良,魏纳,等.全球首次海洋天然气水合物固态流化试采工程参数优化设计[J].天然气工业,2017,37(9):1-14.Zhou Shouwei,Zhao Jinzhou,Li Qingping,Chen Wei,Zhou Jianliang,Wei Na,et al.Optimal design of the engineering parameters for the first global trial production of marine natural gas hydrates through solid fluidization[J].Natural Gas Industry,2017,37(9):1-14.
[11]赵金洲,周守为,张烈辉,伍开松,郭平,李清平,等.世界首个海洋天然气水合物固态流化开采大型物理模拟实验系统[J].天然气工业,2017,37(9):15-22.Zhao Jinzhou,Zhou Shouwei,Zhang Liehui,Wu Kaisong,Guo Ping,Li Qingping,et al.The first global physical simulation experimental systems for the exploitation of marine natural gas hydrates through solid fluidization[J].Natural Gas Industry,2017,37(9):15-22.
[12]魏纳,孙万通,孟英峰,周守为,付强,郭平,等.海洋天然气水合物藏钻探环空相态特性[J].石油学报,2017,38(6):710-720.Wei Na,Sun Wantong,Meng Yingfeng,Zhou Shouwei,Fu Qiang,Guo Ping,et al.Annular phase behavior analysis during marine natural gas hydrate reservoir drilling[J].Acta Petrolei Sinica,2017,38(6):710-720.
[13]高永海,孙宝江,赵欣欣,王志远,殷志明,王金波.水合物钻探井筒多相流动及井底压力变化规律[J].石油学报,2012,33(5):881-886.Gao Yonghai,Sun Baojiang,Zhao Xinxin,Wang Zhiyuan,Yin Zhiming&Wang Jinbo.Multiphase flow in wellbores and variation laws of the bottom hole pressure in gas hydrate drilling[J].Acta Petrolei Sinica,2012,33(5):881-886.
[14]Padsalgikar A.Particle transport in stratified gas-liquid-solid flow[D].Tulsa:The University of Tulsa,2015.
[15]刘建军,邵祖亮,郑永香.天然气水合物降压分解过程的数值模拟[J].西南石油大学学报(自然科学版),2017,39(1):80-90.Liu Jianjun,Shao Zuliang&Zheng Yongxiang.Numberical simulation of the decomposition of natural gas hydrates by depressurization[J].Journal of Southwest Petroleum University(Science&Technology Edition),2017,39(1):80-90.
[16]周守为,李清平,陈伟,付强.天然气水合物开采三维实验模拟技术研究[J].中国海上油气,2016,28(4):1-9.Zhou Shouwei,Li Qingping,Chen Wei&Fu Qiang.Research on3D experiment technology of natural gas hydrate exploitation[J].China Offshore Oil and Gas,2016,28(4):1-9.
[17]Jang CL,Shimizu Y&Lee GH.Numerical simulation of the fluvial processes in the channels by sediment mining[J].KSCEJournal of Civil Engineering,2015,19(3):771-778.
[18]Wang ZM,Hao XN,Wang XQ,Xue L&Guo XL.Numerical simulation on deepwater drilling wellbore temperature and pressure distribution[J].Petroleum Science and Technology,2010,28(9):911-919.
[19]赵金洲,彭瑀,李勇明,田植升,符东宇.基于双层非稳态导热过程的井筒温度场半解析模型[J].天然气工业,2016,36(1):68-75.Zhao Jinzhou,Peng Yu,Li Yongming,Tian Zhisheng&Fu Dongyu.A semi-analytic model of wellbore temperature field based on double-layer unsteady heat conducting process[J].Natural Gas Industry,2016,36(1):68-75.
[20]Xu Jingyu,Zhang Jian,Liu Haifei&Wu Yingxiang.Oil-gaswater three-phase upward flow through a vertical pipe:Influence of gas injection on the pressure gradient[J].International Journal of Multiphase Flow,2012,46:1-8.
[21]付建红,冯剑,陈平,韦红术,刘正礼.深水动态压井钻井井筒压力模拟[J].石油学报,2015,36(2):232-237.Fu Jianhong,Feng Jian,Chen Ping,Wei Hongshu&Liu Zhengli.Simulation on wellbore pressure during dynamic kill drilling in deep water[J].Acta Petrolei Sinica,2015,36(2):232-237.
[22]Dzyuba AV&Zektser IS.Variations in submarine groundwater runoff as a possible cause of decomposition of marine methane-hydrates in the Artcic[J].Water Resources,2013,40(1):74-83.
[23]Kim HC,Bishnoi PR,Heidemann RA&Rizvi SSH.Kinetics of methane hydrate decomposition[J].Chemical Engineering Science,1987,42(7):1645-1653.DOI:https://doi.org/10.1016/0009-2509(87)80169-0.
[24]Windmeier C&Oellrich LR.Theoretical study of gas hydrate decomposition kinetics:Model predictios[J].The Journal of Physical Chenistry,2013,117(47):12184-12195.
[25]Hamaguchi R,Nishimura Y,Inoue G,Matsukuma Y&Minemoto M.Gas hydrate decomposition rate in flowing water[J].Journal of Energy Resources Technology,2007,129(2):102-106.
© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号 地址：北京市海淀区学院路29号 邮编：100083 电话：办公室：(+86 10)66554848；文献借阅、咨询服务、科技查新：66554700 |