【作者】 蔡兵；

【导师】 张强勇；

【作者基本信息】 山东大学 ， 岩土工程， 2013， 硕士

【摘要】 能源储备是当代各国都很重视的一个问题,盐岩具有低渗透率、良好的蠕变行为和损伤自我恢复能力等特点,因此在盐岩介质中储存天然气时能够保证储库的密闭性和在变化储存压力下的储库的稳定性。作为油气储库采出注入的通道,套管的运行安全与否关系到储库资源的顺利开采,是保证油气储库运营的重要枢纽。储气库套管的破损是引起储气库失效的重要原因之一,开展套管失效概率的研究在当前显得比较重要。为了研究套管在不同风险因子下的失效概率变化情况,本文依托973课题——油气储库群运营中的灾变风险评估与调控机制,通过室内试验、理论分析、数值模拟相结合的方法对储气库套管的失效概率展开的研究,本文主要的研究内容下：1.对江苏金坛地下盐岩储气库群套管进行了极端风险因素影响且考虑流变效应的三维地质力学模型试验。通过模型试验得到了不同注采气速率、储库失压、储库运行低压、运行高压等极端风险因素对储库套管运行安全稳定的影响和套管失效概率的变化规律。2.综合分析了国内外学者对蠕变地层套管受力和位移的研究成果,建立了均匀地应力下储气库套管运营风险可靠性分析的计算模型,并且提出基于响应面法的套管可靠性分析方法。3.在储气库运行期间,套管的安全性分析同时考虑到几何尺寸、荷载、材料特性等多因素的随机特性,基于响应面结合蒙塔卡罗抽样法对储气库运行期套管系统的失效概率及敏感性因素进行了分析,主要结论是对于套管运行影响最大是套管厚度和储气库内压。4.通过数值模拟计算了在不同工况下套管可靠度的变化情况。与地质模型试验结果进行对比,验证了数值模拟结果的可靠性。5.在储气库运营过程中,针对不同的风险因子,提出了套管和储气库的调控措施。更多还原

【Abstract】 The salt rock has the properties of low permeability, creep behavior, damage self healing ability and other good characteristics, therefore it can provide a good storage cavern of natural gas with leakproofness and stability in spite of the dynamic stress. Casing as a migration channel concerns oil-gas production directly, which is an important hub to assure oil and gas wells operation normaly after drilling and well completion. The casing breakage is one of the important causes of gas storage failure. It is important to develop the research of the casing failure probability. So in order to explore the risk of casing, under the support of973subject--Risk assessment of catastrophe and regulation mechanism for soil and gas storage in the operation process, this paper adopts combination of experiments、theoretical analysis and numerical simulation. The content included in the article are presented as follows:1) The large-scale3-D rheological geomechanical model test of deep salt rock gas storages was carried out with the salt rock gas storage in Jintan, Jiangsu province as background. The influence of different risk factors (such as different gas injection velocity, high pressure, low pressure, loss of pressure) on the safety of casings were revealed effectively.2) Based on synthetically analysis of all kinds of researched results about casing loads and displacement in creep stratum. On the base of then presents casing safety analysis in creep stratum under uniform in-suit stresses are studied.3) During the operation storage, stochastic characters of geometrical size, load and material of the casing system are analyzed, which are applied in the safety analysis, failure probability calculation and sensitive factors analysis based on response surface method. As a calculation, casing thickness and gas press are important to the casing safety.4) The different conditions was simulated by the finite element method. And the calculation result is proved by the large-scale3-D geological model test. 5) The basic requirements of risk control of the salt cavern storage and casing during the operational period are proposed. The measures of risk control of cavern failure and casing failure.更多还原