Design and operation problems related to water curtain system forunderground water-sealed oil storage caverns

The underground water-sealed storage technique is critically important and generally accepted for the national energy strategy in China. Although several small underground water-sealed oil storage caverns have been built in China since the 1970s, there is still a lack of experience for large-volume underground storage in complicated geological conditions. The current design concept of water curtain system and the technical instruction for system operation have limitations in maintaining the stability of surrounding rock mass during the construction of the main storage caverns, as well as the long-term stability. Although several large-scale underground oil storage projects are under construction at present in China, the design concepts and construction methods, especially for the water curtain system, are mainly based on the ideal porosity medium flow theory and the experiences gained from the similar projects overseas. The storage projects currently constructed in China have the specific features such as huge scale, large depth, multiple-level arrangement, high seepage pressure, complicated geological conditions, and high in situ stresses, which are the challenging issues for the stability of the storage caverns. Based on years’ experiences obtained from the first large-scale （millions of cubic meters） underground water-sealed oil storage project in China, some design and operation problems related to water curtain system during project construction are discussed. The drawbacks and merits of the water curtain system are also presented. As an example, the conventional concept of “filling joints with water” is widely used in many cases, as a basic concept for the design of the water curtain system, but it is immature. In this paper, the advantages and disadvantages of the conventional concept are pointed out, with respect to the long-term stability as well as the safety of construction of storage caverns. Finally, new concepts and principles for design and construction of the underground water-sealed oil storage caverns are proposed.

Key issues in water sealing performance of underground oil storage caverns: Advances and perspectives

Water sealing performance is important for underground water-sealed oil storage(UWSOS).The key issues concerning water sealing performance mainly include the permeability of fractured rock mass(FRM),water-sealed safety(WSS),water curtain performance,and prediction and control of water inflow.This paper reviews the progress of above four key issues on water sealing performances.First,the permeability of an FRM is the basis of water sealing performance,and several commonly used permeability test methods and spatial variation characteristics of permeability are outlined.Second,the current water sealing criteria are compared,and the evaluation methods of WSS are summarized.Third,the design parameters and efficiency evaluation of water curtain systems(WCSs)are introduced.The water inflow of oil storage caverns(OSCs)can reflect the water sealing effect,and the prediction methods and control measures of water inflow are also summarized.Finally,the advantages and disadvantages of the current research are discussed,and the potential research directions are pointed out,such as optimization of water sealing criteria and FRM model,quantitative evaluation of WCS efficiency,accurate prediction of water inflow,and improvement of grouting technology.

A new evaluation method for site selection of large underground water-sealed petroleum storage depots

Scientific site selection is the first step in constructing underground water-sealed petroleum storage depots, but no uniform standard and code for such activity has been established. Therefore, the main objective of this study is to propose an evaluation method for the site selection of an underground water-sealed petroleum storage depot. The first large underground water-sealed petroleum storage depot being built in China served as the background of this study. The following 12 indexes were used as evaluation factors based on comprehensive evaluation criteria and specifications for key project site selection: geographic structure development feature, topographic feature, lithostratic formation feature, crustal stress, strength of rock mass, joint development feature, hydrogeological conditions, long-term water sealing conditions, environmental/ecological vulnerability, regional stability, technical and economic conditions, and meteorological and hydrological conditions. The weight back analysis and power coefficient methods were also used to evaluate the site selected for the first underground water-sealed petroleum storage depot project. Petroleum site classification models based on the two aforementioned methods were established and used to verify the feasibility of the evaluation criteria and methods, and the evaluation results show the grade of the site selected for the underground water-sealed petroleum storage depot in Huangdao, China is good. The study results may be used as a reference for the site selection of future underground water-sealed petroleum storage depots.

Study on the Thermal Ignition of Gasoline-air Mixture in Underground Oil Depots based on Experiment and Numerical Simulation

The study on the special phenomenon,occurrence process and control mechanism of gasoline-air mixture thermal ignition in underground oil depots is of important academic and applied value for enriching scientific theories of explosion safety,developing protective technology against fire and decreasing the number of fire accidents.In this paper,the research on thermal ignition process of gasoline-air mixture in model underground oil depots tunnel has been carried out by using experiment and numerical simulation methods.The calculation result has been demonstrated by the experiment data.The five stages of thermal ignition course,which are slow oxidation stage,rapid oxidation stage,fire stage,flameout stage and quench stage,have been firstly defined and accurately descried.According to the magnitude order of concentration,the species have been divided into six categories,which lay the foundation for explosion-proof design based on the role of different species.The influence of space scale on thermal ignition in small-scale space has been found,and the mechanism for not easy to fire is that the wall reflection causes the reflux of fluids and changes the distribution of heat and mass,so that the progress of chemical reactions in the whole space are also changed.The novel mathematical model on the basis of unification chemical kinetics and thermodynamics established in this paper provides supplementary means for the analysis of process and mechanism of thermal ignition.

辽宁锦州南部应力场特征及其对地下水封油库稳定性影响分析

区域应力场是构造运动的驱动力,是地壳应力研究中的重要内容,现今构造应力与地质资源的储存、开采及基础建设工程的设计实施具有密切联系。文章对锦州南部地区9个钻孔进行了翔实的现场水压致裂原地应力测试,并依据强度与应力指标,对应力状态和岩爆风险分别进行了评价与预测。结果表明,测区最大和最小水平主应力量值分别为3.92~17.33 MPa和3.00~8.93 MPa,垂直应力值为0.80~4.58 MPa,最大水平主应力方向在N33°~88°E之间,优势方位为N72°E;地应力评价结果显示为低~很低应力状态,工程区地下厂房附近无岩爆风险。

地下水封油库场址地应力场及工程稳定性分析研究

建设战略地下水封石油储备库是完善国家石油储备体系的重要途径之一。鉴于此,我国拟在渤海湾附近投资兴建一大型战略石油储备库。由于地下水封油库特殊的地下结构形式,需要对工程区范围内的地应力的量值和方向进行详细的研究分析。在工程区共布置5个水压致裂地应力测点,实际测值相对较为离散,各个测点之间很难找到内在联系,因此利用Sheorey模型对5个测点的测值进行了归一化处理,较为准确地给出洞身部位的应力值大小,即最大水平主应力为11.02±1.0 MPa,最小水平主应力范围为6.82±1.0 MPa,最大主应力的方向为76°(±13°),这与B.C.Haimson等人在朝鲜半岛的研究成果较为吻合,实测地应力场方向与世界应力图所给出的区域构造应力场的方向极为一致,即WSW-ENE到E-W之间。按照修正后的岩体强度应力比方法评价工程区的应力状态可知,地应力量值中等,地应力场对地下工程稳定性影响不大。在这样的远场应力条件下,按照开挖后洞室截面周边最大应力和洞室围岩岩体强度之比的分析计算结果,如果洞室轴线沿最大水平主应力方向布置,在开挖过程中,地下洞室围岩基本以线弹性变形为主,局部受节理裂隙面影响的岩体会出现掉块现象。选择合适的洞室截面形状及洞室轴线和地应力场最大水平主应力方向之间的夹角对洞室的稳定性至关重要。

山洞油库油气扩散蔓延的数值仿真

山洞油库主坑道油气扩散蔓延的研究对油库防爆抑爆安全工作有重要的指导意义。针对山洞油库实际主坑道结构形式,建立起了油气扩散蔓延的CFD数值仿真模型。根据山洞油库主坑道中油气扩散蔓延的湍流特征,采用Realizable k-ε双方程湍流模型对湍流进行模拟,采用有限体积法对仿真模型的控制方程进行离散,并用PISO算法对控制方程进行求解。仿真结果与模拟实验结果较吻合,得出模拟主坑道受限空间中油气扩散蔓延的四个阶段性规律与特性,分析了进气口处油气扩散蔓延的分叉特殊现象。为山洞油库安全管理、应急抢险等工作提供理论依据。

油料洞库坑道油气蔓延规律与特性模拟实验研究

油料洞库储存着大量的易燃易爆油品,防火防爆工作是油库安全工作的核心。对单侧洞口油料洞库狭长地下坑道中的油气蔓延过程进行了模拟实验研究,研究结果表明：油气在狭长地下坑道中的蔓延过程大致可分为4个阶段：开始阶段、增长阶段、发展阶段、稳定阶段;蔓延呈明显的分层流动现象,且在发展阶段中处于稳定的分层蔓延;油料洞库的坑道结构对油气蔓延影响较大,在泄露点和洞库封闭端应当加强安全控制与检测。

山洞油库地下管沟油气泄漏聚集量的预测研究

在分析山洞油库具体空间结构和狭长受限空间内油气蔓延规律与特性的基础上,分别采用灰色GM(1,1)模型和一元线性回归模型对山洞油库地下管沟中的油气聚集量进行了预测,并应用MATLAB软件对预测模型进行编程以简化数学运算,通过对比分析两种预测模型的预测结果与预测误差可以得出:对山洞油库油气聚集量这种近似呈线性增长的预测对象而言,采用灰色GM(1,1)模型比一元线性回归模型具有更高的预测精度,且可确定油气达到爆炸下限的时间以及反映油气浓度变化的规律,以为山洞油库安全状态评估与决策提供依据。

利用示踪棒测量油料洞库模型坑道烟气流动分区

研究火灾燃烧烟气流动规律,对于掌握初期形式为燃烧的单炕道的火灾的发生和发展,以及爆炸后有持续燃烧的火灾发展规律,具有十分重要的意义.在建立的火灾燃烧模拟实验台上,进行了火灾燃烧实验,利用示踪棒对火灾烟气流动的分区进行了测量,对烟气流动分区现象进行了分析.对"死区"和烟气区内流动和分层现象的研究表明,利用示踪棒测量火灾烟气层高度并定性的揭示流动性状是可行的.

地下油料储库火灾分区现象模拟试验与分析

概述了地下油料储库火灾燃烧控制方式、火焰行为及主要影响因素,进行了分区现象模拟试验和分析,结果表明,地下油料储库火灾通常呈现出燃烧区、新鲜空气补充区、烟气流区、过渡区和火焰后面的"惰化区"5区;有上下两层坑道的地下油料储库可呈现出燃烧区、烟气流区、新鲜空气补充区和"情化区"4区。对引发该现象的机理和影响因素作了简要分析。

浅谈新形势下驻城市油库的安全管理

介绍了有些石油库随着城市的扩容逐渐被城市包围所面临的严峻复杂的安全问题,有针对性地提出了对策和建议。

机场地下油库工艺演示系统开发

“机场地下油库工艺演示系统”通过建立机场地下油库设备的高清三维立体模型,展示主要油库设备的外观形貌、内部结构、动作原理等技术指标,为机场供油工程的设计管理和教学研究提供一个直观的技术数据三维平台。本文阐述了开发机场地下油库工艺演示系统的技术要求及技术方案。

机场油库埋地工艺管道腐蚀规律研究

埋地管道随着使用年限的增加,各种不安全因素也随之增加,泄漏事故时有发生。据国内外有关数据资料统计,埋地管道由腐蚀引起的泄漏事故次数占事故总次数的36%~38%。我空军场站近年来亦发生多起机场油库埋地工艺管道由腐蚀引起的泄漏事故,造成较大经济损失。通过本课题的研究可为报废、大修及检修机场油库埋地工艺管道提供可靠依据,继而大大减少因腐蚀引起的泄漏事故。本文介绍了研究机场油库埋地工艺管道腐蚀规律的意义及国内外研究现状;阐述了研究内容及难点;分析了军事及经济效益。

轻油洞库的安全接地

洞库是储存油料的仓库。为保证洞库安全,必须将相关设备设施进行等电位连接,即采取保护接地、重复接地、防静电接地和防雷接地等措施,避免洞库火灾和爆炸事故的发生。

地下油库锚喷支护拱顶圆筒罐室的设计与计算

随着地下工程锚喷支护的广泛应用,以及当前地下支护结构计算方法的提升,考虑到油罐罐室岩质条件好、拱顶圆筒结构受力好,为此提出采用拱顶圆筒锚喷支护结构形式取代当前钢筋混凝土结构,可有效提高工程的安全性、经济性和施工简便性。考虑到拱顶圆筒结构主要承受剪切应力与环向拉应力,为此对抗剪强度与抗拉强度同时进行了折减,并提出了剪切破坏和拉破坏两种安全系数。应用有限元强度折减法除计算剪切破坏安全系数外,还提出了计算拉破坏安全系数的方法。计算得到Ⅱ级围岩稳定安全系数远高于设计要求,Ⅲ级围岩也满足设计要求。在这一基础上提出了实用的锚喷支护结构形式与设计参数。研究表明,锚喷支护拱顶圆筒罐室结构是一种很有前景的结构形式,建议在工程上进一步试验与推广。

建设覆土油罐的利弊分析

介绍了覆土油罐的基本概念、覆土油罐的建设程序和要求,重点分析了覆土油罐的优缺点,并针对缺点提出了做好覆土油罐建设应该完善的制度,保证有章可循;科学设计,确保覆土油罐结构合理;加强监管,保持覆土油罐处于良好状态三项措施。

A study of water curtain parameters of underground oil storage caverns using time series monitoring and numerical simulation

Water curtain systems(WCSs)are key components for the operation of underground oil storage caverns(UOSCs)and their optimization and design are important areas of research.Based on the time series monitoring of the first large-scale underground water-sealed storage cavern project in China,and on finite element analysis,this study explores the optimum design criteria for WCSs in water-sealed oil caverns.It shows that the optimal hole spacing of the WCS for this underground storage cavern is 10 m in order to ensure seal effectiveness.When the WCS is designed with a 10-m horizontal hole spacing and a water curtain pressure(WCP)of 80 kPa,a water curtain hole(WCH)has an influence radius of approximately 25 m.The smaller the vertical distance is between a WCH and the main cavern,the greater the water inflow into the main cavern.The vertical hydraulic gradient criterion can be satisfied when this distance is 25 m.It shows that the optimal WCP is 70 kPa,which meets sealing requirements.

一种石油石化场地污染快速评估方法探究

基于某油库调查数据提出了一种可实现石油石化场地快速污染评估的方法,分别挑选了水质五参数指标、土壤气指标、土壤和地下水实测污染物浓度指标进行数学统计分析,揭示了该场地水土气三相污染的强相关性,确保单相污染推测其它相污染的有效性。整合多维污染数据,进行了检测快速、成本低的指示性指标筛选,通过指示性指标的对比实现了对该场地污染现状的快速评估,为类似场地低成本污染快速判断提供参考。

下穿地下储油库隧洞爆破振动影响及控制措施研究

晋江市引水第二通道工程引水隧洞下穿超近距地面加油站,爆破振动安全问题严峻。施工紧密结合爆破振动监测数据的反馈,通过逐步减少隧洞循环进尺、断面分部分序钻爆、精确的微差起爆网路等弱振动爆破技术,将隧洞爆破在加油站主要控制点的峰值质点振动速度有效控制在安全允许指标以内,绝大多数的振动响应均小于0. 8 cm/s。应用监测结果和数值模拟方法对具有垫沙隔震措施的地下储油库的振动衰减特性进行分析,垫沙隔震措施的减振效果达到50%以上。