溶解乙炔站爆炸半径估算及防火、防爆措施

介绍了国内溶解乙炔的生产工艺流程,对溶解乙炔站可能引起的火灾、爆炸原因进行了分析,估算生产过程中乙炔的爆炸半径.根据爆炸半径,提出防火、防爆措施,为溶解乙炔站的选址及设计提供技术支持.     

600 m3湿式氢气贮柜燃烧爆炸伤害效应预测

建立了某动力公司600m^3易燃易爆湿式氢气贮柜燃烧爆炸事故的6种模型,给出边界条件和计算过程,提出爆炸事故伤害效应预测指标。进行燃烧爆炸事故伤害效应预测,为氢气贮柜发生燃烧爆炸事故危害性评估提供了理论依据。     

Mitigation performance of the process protection system on the accident consequences of H2S-containing natural gas release and explosion

Toxic loads and explosion overpressure loads pose grave threats to the offshore oil and gas industry. Many safety measures are adopted to prevent and mitigate the adverse impacts caused by toxic loads and explosion overpressure loads. As a general safety barrier, the process protection system has been widely used but rarely evaluated. In order to assess the barrier ability, the mitigation performance of the process protection system is concerned in this study. Firstly, several chain accidents of H₂S-containing natural gas leakage and explosion are simulated by varying the response time of the process protection system with CFD code FLACS. Qualitative assessment is conducted based on the variation of the dangerous load profiles. Furthermore, the quantitative assessment of the mitigation performance is accomplished by considering its ability in reducing the probability of fatality. Emergency evacuation and no emergency evacuation are considered respectively in the quantitative assessment. The results prove that the process protection system takes effect on mitigating the toxic impact and explosion overpressure impact. The results also demonstrate that although the emergency evacuation may result in a severer explosion load to the operator, the process protection system can mitigate the adverse impacts regardless of whether the emergency evacuation is conducted or not.     

加油站埋地汽油储罐爆炸定量分析

针对加油站的埋地汽油储罐爆炸进行了定量分析。简要叙述了加油站埋地储罐的埋地方式以及埋地深度等基本情况,运用岩土中的爆炸理论描述分析了埋地储罐爆炸的过程。在计算爆炸冲击波超压时,提出一个计算埋地汽油储罐爆炸冲击波超压的准则:对于埋地汽油储罐爆炸,应当结合汽油储罐的埋地深度以及储罐周围覆土的性质等因素来确定冲击波超压的计算方法。     

桩管成井法施工安全试验研究

在利用垃圾场填埋气体发电成井施工过程中,桩管成井抽气法被普遍应用.但成井过程中的气体爆炸安全问题是一大隐患. 通过施工现场模拟试验和实际成井试验研究,解决了如何防止成井过程中产生气体爆炸危险的方法.     

泄爆容器中粉尘爆炸的试验研究与数值模拟

为了解泄爆容器中粉尘爆炸的发展过程,采用试验和数值模拟相结合的方法对玉米淀粉在圆柱形容器内的泄爆过程进行研究。数值模型采用欧拉–拉格朗日方法模拟粉尘爆炸的两相流问题,通过求解非稳态的湍流两相反应流守恒方程对试验进行二维仿真。试验和模拟结果表明,点火位置对爆炸发展过程有明显影响,点火位置离泄爆口越远,容器中的最大泄爆压力Pred,max越高。在粉尘爆炸的安全防护设计中,应把点火位置作为重要影响因素之一加以考虑。     

超细水雾抑制甲烷爆炸的实验研究(英文)

用自行设计的三面透明的细水雾抑制甲烷爆炸的实验装置,研究了不同体积超细水雾对不同浓度甲烷爆炸的抑制现象。运用GigaView高速摄影观察了超细水雾抑制甲烷爆炸的过程,并且对现象进行了分析。采用四个E12-1-K型快速响应热电偶获取超细水雾抑爆过程中四个不同位置的温度变化情况,并且讨论了甲烷浓度和超细水雾体积对爆炸延迟时间的影响。实验结果表明,超细水雾对甲烷爆炸的抑制效果是与水雾的体积和甲烷浓度紧密相关的。初步确定了超细水雾抑制甲烷爆炸的临界体积。     

储油条件下拱顶油罐的油气爆炸实验

为研究储油条件下拱顶油罐油气爆炸的发展过程,设计了中尺度拱顶油罐油气爆炸实验台架,并完成了储油条件下油罐油气爆炸试验。实验结果表明:储油条件下油气爆炸会导致罐顶破坏,超压发展分为多个阶段,并出现强烈的超压振荡和二次爆炸现象,最大超压由二次爆炸所产生;爆炸最大超压随着初始油气体积分数的降低而升高;在储油条件下,油罐油气爆炸后会诱导产生二次爆炸现象,第2次爆炸超压峰值和升压速率均远大于第1次爆炸的数值,且二次爆炸对外场的影响更加明显;火焰强度随时间的变化曲线具有2个明显的峰值,其形成原因分别为第1次爆炸和第2次爆炸。     

尿素合成塔爆炸事故机理的研究

尿素合成塔工艺条件复杂,体积庞大,内部物料状态复杂,需要在高温、高压下操作,国内外曾发生过几起著名的尿素合成塔爆炸事故,事故后果非常严重。工艺条件的复杂性加大了事故分析的难度,目前对事故原因众说纷纭。利用数值模拟软件,对尿素合成塔爆炸过程进行研究,对爆炸机理进行分析,对事故发生的原因进行探讨,为预防同类事故提供一定的依据。分析了顶部气相空间爆炸性混合体系的形成和爆炸过程,结合数值模拟得出关键点的压力变化和气相冲击波最终的压力,依据能量守恒推导出液相中冲击波的压力。利用数值模拟得出冲击波在液相中的传播速度和叠加的情况,综合反射、直接透射两部分冲击波进入液相的时间差,找到位于筒体底部的叠加点,冲击波在该处叠加造成筒体破裂,过热液体瞬间气化喷出,引发破坏更大的二次蒸汽大爆炸。     

对称障碍物条件下瓦斯爆炸火焰与压力波耦合作用研究

为了研究对称障碍物条件下瓦斯爆炸压力波与火焰传播的耦合作用,在150 mm×150 mm×1 700 mm的有机玻璃瓦斯爆炸管道中,距离点火端不同距离安装0.5阻塞率的对称障碍物,进行8.5%甲烷体积分数的爆炸试验,采集瓦斯爆炸的超压信号并同步拍摄火焰传播图像。结果表明:火焰穿越板式对称障碍物的过程经历了火焰加速、火焰降速到火焰再加速的过程,火焰降速的时间仅为5 ms。距离点火焰源不同长度的对称障碍物在火焰加速过程中的作用存在明显差异,近点火源的障碍物作用主要为诱导湍流,远离点火源的障碍物作用主要为湍流增强。     

面粉增白剂生产过程中发生爆炸的主要原因及防范措施

分析了面粉增白剂主要成份过氧化苯甲酰（ＢＰＯ）在生产过程中发生爆炸的主要原因，对生产、检修、储存等诸环节中可能发生爆炸的危害程度进行了比较，从设施、设备、工艺流程、工具、仪表、制度、人员素质等方面提出了防止爆炸的可行措施     

受限空间中CO与水蒸汽阻尼瓦斯爆炸的反应动力学模拟研究

为了探求一氧化碳与水蒸汽参与瓦斯爆炸的化学反应动力学过程的阻尼效应,建立了受限空间中瓦斯爆炸反应的数学模型。数值计算结果表明,结果表明在瓦斯爆炸过程中,瓦斯-空气混合气体含有10%的一氧化碳,虽然会延迟瓦斯爆炸时间,抑制瓦斯爆炸,但是H、O自由基浓度、瓦斯爆炸温度和压力比不加入一氧化碳时升高,同时对CO2、NO的生成起促进作用;当混合气体中含有10%的水蒸汽时,H、O自由基浓度降低,瓦斯爆炸温度和压力也随之降低,致灾性气体CO2、NO的生成得到抑制。虽然一氧化碳对瓦斯爆炸有一定的阻尼效应,但是由于一氧化碳对部分致灾性气体的生成有促进作用,因此,在阻尼瓦斯爆炸方面,水蒸汽的效果要好于一氧化碳。     

The explosion parameters of methanol under variable pressures and 423 K

The high-temperature and high-pressure methanol one-step oxidation has been the primary process for the mass production of dimethoxymethane. However, the risk of explosion for this process is still not properly defined. This paper presents new results from the experimental study on the explosion characteristics, including the explosion pressure and the explosion limits for methanol/air mixtures with a variable oxygen level, under an initial pressure between 0.3 MPa and 0.75 MPa and at the initial temperature of 423 K. The upper explosive limits were found to increase along with the initial pressure. If the limits for normal air are known, the oxygen effect on flammability is predictable from the thermal balance method. With a correlation for the pressure effect and a method for the oxygen effect, we can have the flammable range predictable.     

Experimental study on water sealing of fire barriers and explosion venting of large-scale pipeline with low-concentration gas

Low-concentration gas transported in pipelines may lead to explosion accidents because gas with a concentration of less than 30% is prone to explode. To reduce the incidence of gas explosions, water sealing of fire barriers is implemented, and explosion venting devices are installed along the pipeline. To investigate their suppression effect on low-concentration gas explosion, experiments using methane–air premixed gas under different conditions were implemented on a DN500 pipeline test system. The effects of three types of explosion venting forms (rupture disc, asbestos board, and plastic film) on explosion overpressure and flame were compared and analysed. Results show that the rupture disc, asbestos board, and plastic film can achieve adequate explosion venting, causing the peak decay rates of explosion overpressure to reach 82.37%, 81.72%, and 90.79%, respectively. The foregoing indicates that the greater the static activation pressure of the explosion venting form, the higher the peak explosion overpressure at each measurement point. Moreover, the shorter the explosion flame duration, the greater the flame propagation velocity. The research results provide an essential theoretical foundation for the effective suppression of gas explosion accidents in the process of low-concentration gas transportation.     

受限空间瓦斯爆炸与氢气促进机理研究

为探索受限空间中瓦斯爆炸及氢气对爆炸过程的影响,采用GRI-Mech 3.0甲烷燃烧机理,建立受限空间中瓦斯爆炸的数学模型,应用CHEMKIN软件,对受限空间内瓦斯爆炸过程及氢气对反应物浓度、活化中心浓度、主要致灾性气体浓度的影响进行模拟分析。通过对反应机理的敏感性分析,找出影响瓦斯爆炸及爆炸后主要致灾性气体生成的关键反应步。结果表明:混合气中分别充入0.5%,2%,3.5%氢气时,爆炸时间分别提前0.005 7,0.010 5,0.011 1 s;爆炸后压力分别提高2.53,4.05,7.60 kPa;爆炸后温度分别提高20,60,100 K。由此可见,随着混合气中氢气含量的增加,瓦斯引爆时间越来越短,其爆炸强度也随之增大,且氢气在一定程度上对有害气体CO,CO2,NO,NO2的生成有很大影响。     

连通容器气体密闭爆炸与泄爆过程的实验研究

利用球型容器与管道组合,开展连通容器气体爆炸与泄爆实验,分析连通条件下,火焰在管道中的传播过程及其对起爆容器和传爆容器的压力影响。实验结果表明:连通容器气体爆炸中,火焰从起爆容器到传爆容器传播经历了一段不断加速,但加速度不断减小的过程;泄爆过程中,火焰传播过程与密闭爆炸时基本一致。管道中火焰加速传播,使得传爆容器的爆炸压力和强度相较于作为起爆容器时均明显增加,危险更大,采用与起爆容器相同的泄爆面积,无法满足对连通容器中传爆容器的泄爆。同时,泄爆是一个快速的能量泄放过程应选择合理的泄爆方式,防止二次危害。     

Initial phase modelling in numerical explosion applied to process safety

The utilisation of computational fluid dynamics (CFD) in process safety has increased significantly in recent years. The modelling of accidental explosion via CFD has in many cases replaced the classical Multi Energy and Brake Strehlow methods. The benefits obtained with CFD modelling can be diminished if proper modelling of the initial phase of explosion is neglected. In the early stages of an explosion, the flame propagates in a quasi-laminar regime. Proper modelling of the initial laminar phase is a key aspect in order to predict the peak pressure and the time to peak pressure. The present work suggests a modelling approach for the initial laminar phase in explosion scenarios. Findings are compared with experimental data for two classical explosion test cases which resemble the common features in chemical process areas (confinement and congestion). A detailed analysis of the threshold for the transition from laminar to turbulent regime is also carried out. The modelling is implemented in a fully 3D Navier–Stokes compressible formulation. Combustion is treated using a laminar flamelet approach based on the Bray, Moss and Libby (BML) formulation. A novel modified porosity approach developed for the unstructured solver is also considered. Results agree satisfactorily with experiments and the modelling is found to be robust.     

矿井瓦斯煤尘爆炸传播数值模拟研究

基于连续相、燃烧、颗粒相数理方程建立瓦斯煤尘爆炸传播数理模型,并应用连续相、颗粒相计算方法,依据大型巷道瓦斯爆炸、瓦斯煤尘爆炸传播实验数据,借助普遍应用的流场模拟平台,成功开发瓦斯、煤尘爆炸数值模拟系统。该系统可有效地模拟煤矿瓦斯、煤尘的爆炸事故过程,对瓦斯爆炸的爆燃转爆轰、煤尘是否参与爆炸、爆炸冲击传播速度、衰减规律以及爆炸灾害的波及范围都能进行较准确的模拟。     

液化石油气汽车罐车爆炸事故原因分析及预防

通过一起液化石油气汽车罐车的爆炸事故,分析出装卸软管在卸车过程中破裂是爆炸事故的主因,提出了有效预防措施。同时对汽车罐车的安全运行在使用管理方面提出了建议。     

基于扎根理论的瓦斯爆炸风险累积效应研究*

为研究瓦斯爆炸风险在事故发展中的累积过程，揭示瓦斯爆炸事故的风险累积机理，引入累积效应的研究思想。首先界定风险累积概念，分析风险累积过程；然后运用案例研究、专家调查等方法分析瓦斯爆炸风险累积的累积源、途径，并应用扎根理论方法提取风险类型并研究风险累积过程；在此基础上，运用系统动力学软件绘制瓦斯爆炸风险累积路径图，将风险的累积过程可视化。研究表明:瓦斯爆炸风险存在累积过程，主要通过加和累积和放大累积方式累积，累积时间越长，越易引发新风险，其中管理风险累积影响人、物、环的状态，而人、物、环风险累积过程直接影响瓦斯爆炸事故发生进程。研究结果为瓦斯爆炸事故原因分析提供1种新方法，对煤矿企业的事故预防和风险管控具有一定指导和参考意义。