The Setting Depth of the Testing Safety Valve in Deepwater Oil and Gas Wells for Gas Hydrate Blockage Prevention
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摘要:
深水油气井测试过程中，容易发生气体水合物堵塞井下安全阀的问题，为避免出现该问题，研究了安全阀合理下入位置的确定方法。利用气体水合物相平衡微观试验装置，在室内模拟了地层水矿化度下多组分气体水合物在水中的相变过程，得到了温度和压力对气体水合物相平衡的影响规律；分析了气体组分、水深、地温梯度和井口压力对生成气体水合物的影响，预测了气体水合物的生成区域，从安全和成本2方面考虑给出了安全阀最小下入深度的确定方法。研究发现，气体组分、水深、地温梯度、井口压力均会影响安全阀的下入位置，产出气中乙烷、丙烷和丁烷含量增加更易生成气体水合物；同时，水深越深，地温梯度越小，井口压力越大，生成气体水合物的区域越大，安全阀需要下入到更深的位置。研究认为，上述研究成果可为深水油气井测试中安全阀下入位置的确定提供参考。
Abstract:During the testing of deep water oil and gas wells, gas hydrate is prone to block downhole safety valves. To prevent it from happening, a method for determining the reasonable setting depth of safety valve was studied. The gas hydrate phase of equilibrium micro-test device was used to simulate the phase transition process of multi-component gas hydrates under various formation water salinities in the laboratory and to obtain the influencing law of temperature and pressure on the phase equilibrium of gas hydrate. The effects of gas composition, water depth, the geothermal gradient and wellhead pressure on the formation of gas hydrate were analyzed to predict the formation area of gas hydrate, and the method in determining the minimum setting depth of safety valve was obtained from the aspects of safety and cost. Studies suggest that all the factors including gas composition, water depth, geothermal gradient, and wellhead pressure could affect the setting depth of safety valve, and the increased contents of ethane, propane and butane in the produced gas are more likely to form gas hydrates. In addition, the setting depth of the safety valve will be further lower as deeper water depth, smaller geothermal gradient, higher wellhead pressure, and larger gas hydrate formation area. The results of this study could provide a reference for determining the setting depth of test safety valve in deep water oil and gas wells.
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Keywords:
- gas hydrate /
- deepwater oil and gas /
- safety valve /
- gas hydrate blockage /
- phase equilibrium
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图 1 气体水合物相平衡微观试验装置结构
1.气瓶；2.注液泵；3.进液阀；4.压力表；5.进气阀；6.排液阀；7.可视窗；8.水浴夹套；9.反应釜；10.温度传感器；11.压力传感器；12.数据控制箱；13.光学显微镜
Figure 1. Structure of gas hydrate phase equilibrium micro-test device
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图 2 多组分气体水合物微观分解过程
Figure 2. Micro-decomposition process of multi-component gas hydrate
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图 3 地层水矿化度下多组分气体水合物的相平衡曲线
Figure 3. Phase equilibrium curve of multi-component gas hydrates under formation water salinity
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图 4 不同摩尔分数甲烷和乙烷组合气体水合物的相平衡曲线
Figure 4. Phase equilibrium curves of gas hydrates with different molar ratios of methane and ethane
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图 7 甲烷中加入相同摩尔分数乙烷、丙烷和丁烷的气体水合物的相平衡曲线
Figure 7. Phase equilibrium curves of gas hydrate prepared by adding the same molar ratio of ethane, propane and butane into methane
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图 5 不同摩尔分数甲烷和丙烷组合气体水合物的相平衡曲线
Figure 5. Phase equilibrium curves of gas hydrates with different molar ratios of methane and propane
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图 6 不同摩尔分数甲烷和丁烷组合气体水合物的相平衡曲线
Figure 6. Phase equilibrium curves of gas hydrates with different molar ratios of methane and butane
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图 8 安全阀下入位置确定方法示意
Figure 8. Schematic of determining the setting depth of safety valve
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[1] SLOAN E D, KOH C A. Clathrate hydrates of natural gas[M]. 3rd ed. Boca Raton: CRC Press, 2007: 1-11.
[2] 关利军,任金山,孙宝江,等. 深水气井测试水合物抑制剂优选及注入方法[J]. 中国海上油气, 2014, 26(2): 55–60. GUAN Lijun, REN Jinshan, SUN Baojiang, et al. An optimization and of hydrate inhibitors and its injection method for the testing of deep water gas wells[J]. China Offshore Oil and Gas, 2014, 26(2): 55–60.
[3] SY/T 10024—1998 井下安全阀系统的设计、安装、修理和操作的推荐作法[S]. SY/T 10024—1998 Recommended practice for design, installation, repair and operation of subsurface safety valve system[S].
[4] 谢梅波,岳江河,王海东. 各类井下安全阀系统的特点及安装设计概述[J]. 中国海上油气(工程), 1995, 7(4): 31–42. XIE Meibo, YUE Jianghe, WANG Haidong. The feature of various downhole safety valve system and overview of installation design[J]. China Offshore Oil and Gas (Engineer), 1995, 7(4): 31–42.
[5] GARY B, HOSLI C, LUVIANO A, et al. Tubing retrievable surface controlled subsurface safety valve floating flapper remediation[R]. SPE 168271, 2014.
[6] 李林涛,万小勇,李渭亮,等. 高压井下安全阀的研制及性能评价[J]. 重型机械, 2018(6): 12–14. doi: 10.3969/j.issn.1001-196X.2018.06.003 LI Lintao, WAN Xiaoyong, LI Weiliang, et al. Development and performance evaluation of high pressure subsurface safety valve[J]. Heavy Machinery, 2018(6): 12–14. doi: 10.3969/j.issn.1001-196X.2018.06.003
[7] 张俊良,邵勇,贾长青,等. 高含硫气井井下安全阀失效的对策及现场实践[J]. 天然气技术与经济, 2018, 12(1): 32–34. doi: 10.3969/j.issn.2095-1132.2018.01.009 ZHANG Junliang, SHAO Yong, JIA Changqing, et al. Counter-measures against failure of subsurface safety valve used for a highsour gas well and their application[J]. Natural Gas Technology & Economy, 2018, 12(1): 32–34. doi: 10.3969/j.issn.2095-1132.2018.01.009
[8] 孙天礼,张广东,张文洪,等. 大牛地气田水合物堵塞预测与防治[J]. 中国科技成果, 2008(18): 42–45. doi: 10.3772/j.issn.1009-5659.2008.18.013 SUN Tianli, ZHANG Guangdong, ZHANG Wenhong, et al. Prediction and control of hydrate blockage in Daniudi Gas Field[J]. China Achievement of Science and Technology, 2008(18): 42–45. doi: 10.3772/j.issn.1009-5659.2008.18.013
[9] 孙志高,石磊,樊栓狮,等. 气体水合物相平衡测定方法研究[J]. 石油与天然气化工, 2001, 30(4): 164–166. doi: 10.3969/j.issn.1007-3426.2001.04.002 SUN Zhigao, SHI Lei, FAN Shuanshi, et al. Study of the measuring methods of gas hydrate phase equilibrium[J]. Chemical Engineering of Oil and Gas, 2001, 30(4): 164–166. doi: 10.3969/j.issn.1007-3426.2001.04.002
[10] 陈光进, 孙长宇, 马庆兰．气体水合物科学与技术[M]．北京: 化学工业出版社, 2008: 9-11． CHEN Guangjin, SUN Changyu, MA Qinglan. Gas hydrate science and technology[M]. Beijing: Chemical Industry Press, 2008: 9-11.
[11] 邓柯,李颖川,李群生. 天然气水合物生成的影响因素及敏感性分析[J]. 钻井液与完井液, 2006, 23(6): 64–67. doi: 10.3969/j.issn.1001-5620.2006.06.021 DENG Ke, LI Yingchuan, LI Qunsheng. The generation of natural gas hydrates: contributing factors and sensitivity analysis[J]. Drilling Fluid & Completion Fluid, 2006, 23(6): 64–67. doi: 10.3969/j.issn.1001-5620.2006.06.021
[12] 许威,邱楠生,孙长宇,等. 不同因素对天然气水合物稳定带厚度的影响[J]. 天然气地球科学, 2010, 21(3): 528–534. XU Wei, QIU Nansheng, SUN Changyu, et al. Effects of different factors on the thickness of gas hydrate stability zone[J]. Natural Gas Geoscience, 2010, 21(3): 528–534.
[13] 张振楠,孙宝江,王志远,等. 深水气井测试天然气水合物生成区域预测及分析[J]. 水动力学研究与进展(A辑), 2015, 30(2): 167–172. ZHANG Zhennan, SUN Baojiang, WANG Zhiyuan, et al. Predic-tion and analysis of natural gas hydrate formation region during deep water gas well testing[J]. Chinese Journal of Hydrodynamics, 2015, 30(2): 167–172.
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