车用气瓶检测站危险分析

减轻车辆对环境污染,公共交通汽车大力发展清洁燃料汽车,燃料为液化石油气和压缩天然气.盛装液化石油气和压缩天然气的容器为气瓶,为保证车用气瓶的安全使用,必须对车用气瓶进行检测.本论文根据检验工艺和物质的特性,对北京市新建车用气瓶检测站进行安全分析,并提出了安全控制措施.     

液化石油气储罐事故应急处鸯

随着石油化学工业的发展,液化石油气作为一种化工基本原料和新型燃料得到日益广泛的应用,与此同时,液化石油气储罐却因保存或使用不当屡屡发生事故.     

液化石油气站危险源控制

由于液化石油气是一种高热值燃料,已在工业生产和民用方面得到越来越广泛的应用.液化石油气是易燃易爆气体,爆炸极限低.点燃能量小,加上液态石油气减压后易气化,单位重量气态石油气是液态时的250～300倍,因此,少量的液化石油气泄漏,也会造成大量泄漏时的同样结果,一旦与明火相遇,就会形成很大范围的火灾爆炸区域.国内外由于液化石油气引发的特大事故屡见不鲜,因此液化石油气站的危险源控制就显得极端重要.     

液化石油气钢瓶承载能力的研究

充分考虑液化石油气钢瓶的结构特点,基于31组试验数据,推导得到确定短液化石油气钢瓶承载能力的新公式,以及区分长、短液化石油气钢瓶的临界长度计算公式;采用11组试验数据验证了用中径公式确定长液化石油气钢瓶承载能力的合理有效性.     

液化石油气的应急处置原则有哪些？

液化石油气是由石油加工过程中得到的一种无色挥发性液体,主要组分为丙烷、丙烯、丁烷、丁烯,并含有少量戊烷、戊烯和微量硫化氢等杂质。不溶于水。主要用作民用燃料、发动机燃料、制氢原料、加热炉燃料以及打火机的气体燃料等．也可用作石油化工的原料。     

液化石油气储罐泄漏事故后果类型分析

液化石油气是从油气田或石油炼制过程中得到的一部分碳氢化合物。主要成分为C3、C4烷烃。液化石油气(LPG)是重要的燃料及化工原料,同时也是一种易燃、易爆的危险物质,在生产运输,储存和使用过程中极易发生事故。随着液化石油气在工业与民用方面的广泛应用,国内外因操作和管理不慎而发生的液化石油气火灾爆炸事故屡见不鲜。1984年11月19日,墨西哥市郊外国家石油公司液化石油气储运站发生泄漏并引发爆炸,造成650人死亡,6000人受伤。1998年3月5日,西安市煤气公司液化石油气管理所发生严重泄漏爆炸事故,共造成12人死亡,32人受伤,10万居民疏散。这些事故造成的人身伤亡及财产损失等都极为严重。因此,对液化石油气储罐及其管路的事故后果进行分析,提出相应的对策措施,对预防重大事故的发生具有重要意义。     

燃气汽车驾驶操作注意事项

目前已在我国开始使用的燃气汽车主要有两大类：一类是在原汽油发动机的基础上增加一套燃气（压缩天然气CNG或液化石油气LPG）供给系统,称之为“两用燃料汽车”。两用燃料发动机工作时,要么使用汽油,要么使用燃气,燃油和燃气不可同时使用;另一类是在原柴油机的基础上增加一套燃气（CNG或LPG）供给系统,     

加气站常见火灾隐患排查

加气站,是以压缩天然气（CNG）或液化石油气（LPG）等形式向新能源汽车提供燃料的场所。天然气的主要成分是甲烷,液化石油气的主要成分是丙烷和丁烷,均属于易燃物质。甲烷比空气轻,扩散能力强;液化石油气挥发后的气体比空气重,容易集聚在地面的空隙、管道、下水道等低洼处;这些物质与空气混合后,当达到一定浓度,一旦遇到火源极易发生燃烧爆炸。     

高原液化石油气管道的腐蚀现状与防护

昌都市主要的燃料源为由液化石油气站供应的液化石油气,其站内管道发生腐蚀失效将产生严重的事故后果。文中针对高原环境的特点对在用液化石油管道腐蚀现状进行调查,对架空管道和埋地管道分别进行了腐蚀原因分析。从隔绝阳光直射、做好涂层防护、增加管道阴极保护系统等方面提出防护措施,以期为保持液化石油气管道的使用性能、保障周边居民的生命财产安全提供参考价值。     

液化石油气槽车泄漏事故处置

液化石油气是我国城镇居民的主要生活燃气之一,也是一种重要的工业燃料．我国每年消耗的液化石油气在1000万吨以上,用以生产、储存、运输和使用液化石油气的装置,遍及城市的各个角落。作为燃料,液化石油气具有热值高、无污染等特点,使用的普及率越来越高。     

柴油汽车掺烧LPG降低黑烟排放技术

研究了柴油机掺烧液化石油气(LPG)以降低黑烟排放的技术方案，并开发出了一种以独特型板调节装置为特征的机械控制式柴油/LPG双燃料供给系统。发动机不改变原有结构加装该系统后即成为柴油/LPG双燃料发动机，可以同时燃烧柴油和LPG两种燃料，并且在整个工作范围内，随着工况变化能够按照预先优化设定的型板型线规律而自动调节柴油／LPG供给量比例，使烟度降低50％以上，同时满足经济性、动力性以及操作性能等要求，此外，也可以切换为单独燃烧柴油，而不改变发动机的原有性能。该系统结构简单、成本低廉，非常适合于改装城市在用公交车，降低其黑烟排放。     

An experimental investigation of fluid flow and combustion characteristics of dual-fuel in a cylindrical combustion chamber

Combustion and fluid flow characteristics of coflowing LPG and kerosene have been investigated experimentally. A cylindrical water cooled combustion chamber was used to investigate the effect of changing the injection location and percentage of liquid fuel during gaseous fuel combustion. It was found that the injection of liquid fuel leads to an increase in the absolute value of maximum positive axial velocity and reduces the absolute value of the maximum negative axial velocity compared to the case of LPG alone. Also, a stable temperature distribution is noticed at axial distance of X/D approximately equal to 2.15 (where X is the axial distance measured from the inlet of diffuser, and D is chamber diameter). This is less than that of gaseous fuel combustion (approximately equal to 2.91). The change of injection location leads to a reduction in values of gas temperatures at X_inj/D=0.15 then it increased to reach maximum values at X_inj/D=0.35 which is approximately the same value for combustion of LPG fuel only. Any further increase in the injection location leads to a reduction in gas temperature, especially at the upstream sections of the combustion chamber. Also, it was found that values of temperature along the combustion chamber were decreased with increasing the percentage of the injected liquid fuel due to incomplete combustion of liquid fuel. Values of combustion chamber efficiency (η) for all percentage of liquid fuel at X_inj/D=0.35 are higher than those for combustion of LPG alone.     

生态驾驶行为对单个小汽车运行状态的综合影响分析

为了进一步明确我国实际道路交通条件下生态驾驶行为对车辆运行状态的综合影响,助力生态驾驶行为推广应用策略,结合驾驶模拟和实车驾驶试验,重点分析了生态驾驶行为对单个小汽车能耗、排放及运行效率的影响。结果表明:生态驾驶行为能有效降低机动车能耗和尾气排放;同时,相同条件下,生态驾驶行为降低车辆能耗的比例远大于车辆行驶时间增加的比例。因此,对单个小汽车而言,生态驾驶行为的节能效益大于其对车辆运行效率的影响。     

Experimental Study on the Potential Application of Cottonseed Oil–Diesel Blends as Fuels for Automotive Diesel Engines

This paper presents the results of an experimental study on the direct application of cottonseed oil–diesel blends as fuel for diesel engine vehicles without using additional retrofit mechanical systems. The use of biofuels is one of the main actions promoted by the European Union and member states in an effort to tackle global warming, enhance energy security and contribute to regional development. Here, the possibility to blend cottonseed oil directly with fossil diesel as a fuel for diesel engines is examined. This option has lower cost and larger well-to-wheel greenhouse gas benefits than fatty acid methylesters. The paper presents measurements of important fuel properties, density, viscosity, cetane number and cold flow characteristics. In addition, a common rail Euro 3 compliant diesel car is tested using 10% v/v cottonseed oil–diesel blends in order to examine the effects on performance and emissions of regulated pollutants and CO₂. Furthermore, particle emission characteristics are studied, including total and solid particle number concentrations and particle size distributions over driving cycles and steady state modes. The results indicate that the test fuel presents good operating characteristics and limited effects on regulated emissions and vehicle performance. These results would justify further research on the direct use of vegetable oils as automotive fuels.     

Fuel recovery from waste oily sludge using solvent extraction

Solvent extraction was used to recover oil from waste sludge generated from the storage of crude petroleum. Different solvent-to-sludge mass ratios were used for two solvents, methyl ethyl ketone (MEK) and LPG condensate (LPGC). Several parameters were compared, such as oil recovery as a percent of the original sludge mass, and reduction in carbon residue, ash content, and asphaltene content. A 4:1 solvent-to-sludge ratio was found to be optimum for both solvents. The MEK extraction recovered 39% by mass of the sludge as recovered oil. The LPGC recovered 32%. The amount of asphaltenes in the fuel oil was related to the concentration of fuel oil in the solvent phase during the extraction, suggesting that asphaltenes are extracted mainly by the fuel oil components, not the solvent. The physical properties and metal content of the recovered oil were measured. The recovered oil was distilled to provide diesel fuel. This diesel fuel contained high levels of sulfur and carbon residue, as well as a high diesel index, indicating the fuel requires further treatment prior to use as a fuel.     

Hazard analysis on LPG fireball of road tanker BLEVE based on CFD simulation

In order to research the hydrocarbon fireball characteristic of LPG tanker Boiled Liquid Evaporate Vapor Explosion (BLEVE) under different conditions, computational fluid dynamics (CFD) simulations of the hydrocarbon fireballs from the LPG tanker BLEVE accidents were carried out. Several new different factors, such as the mass of fuel, inlet velocity and airflow velocity, were considered to analyze the influence on the evolution of the characteristics of the fireball and the development of the LPG tanker BLEVE accidents. Results indicate that the fireball with a greater mass of fuel radiates more heat but slower. The large longitudinal diameter of the fireball and high radiation heat flux are observed in case of a faster inlet velocity used for the same mass. The airflow was found to shorten the initial phase of the fireball effectively. Some suggestions were proposed to prevent the LPG BLEVE accidents. Analysis performed show that various parameters like fireball diameter, radiative heat flux and lifting speed of fireball can be predicted well using FDS code.     

直喷式柴油机燃用脂肪酸甲酯的排放特性

脂肪酸甲酯是由生物脂肪经过酯化反应得到的脂肪酸单酯,具有良好的燃料品质和环境友好性,是生物柴油众多种类中的一种.以纯矿物柴油、脂肪酸甲酯、含30%脂肪酸甲酯与70%柴油的混合燃料和含50%脂肪酸甲酯与50%柴油的混合燃料为燃料,在四缸涡轮增压直喷式柴油机上进行的性能对比实验,表明柴油机燃用脂肪酸甲酯能够保持其动力性和燃料经济性,可以显著降低HC和碳烟排放,但会增加CO和NOx排放.脂肪酸甲酯可以作为柴油机的代用燃料进行推广.     

Computational fluid dynamics (CFD) study of heat radiation from large liquefied petroleum gas (LPG) pool fires

Liquefied petroleum gas (LPG) is flammable and has risks of pool fires during its transportation, storage, and applications. The heat radiation by LPG pool fires poses hazards to individuals nearby and can lead to potential failures of ambient facilities. Due to the high costs and invasive nature of experiments for investigating large-scale pool fires, computational fluid dynamics (CFD) is employed in this study as the cost-effective and noninvasive method to simulate the process and analyze the characteristics of large hydrocarbon pool fires. Specifically, an experimentally validated 3-D CFD model has been built to simulate surface emissive power (SEP) and incident radiation of large-scale LPG pool fires with three different diameters and wind speeds. Steady-state simulations with P1 radiation and probability density function (PDF) combustion models were employed to obtain reliable data after the optimizations based on the comparisons with experimental data and empirical models. The comparison with benchmark experimental data demonstrates that the CFD model employed in this study can accurately predict the incident radiation of large LPG pool fires. A new SEP correlation is also proposed, which is specifically for LPG pool fires with a diameter between 10 m and 20 m. Additionally, the safe separation distances between LPG facilities and surrounded objects have been estimated based on the CFD simulation results. The high-resolution CFD model for large LPG pool fires in this work provides noninvasive and direct quantitative evidence to enhance the fundamental understanding on the safety of large LPG pool fires and can assist regulatory agencies in refining the safety limits in the cost-effective and time-saving manners.     

车载储氢瓶泄漏及车库内通风方式研究*

为研究车库内燃料电池汽车氢气意外泄漏后的浓度分布情况,采用ANSYS软件,通过分析可燃性气体体积、水平方向和垂直方向氢气的扩散分布、不同泄漏位置氢气的扩散情况,研究6种不同通风方式对氢气意外泄漏扩散分布的影响,针对车库内氢气泄漏的特性,在通风方式上引入侧墙底部送风和侧墙顶部送风方式。研究结果表明:底部送风能显著加快氢气的扩散和排出。垂直高度上氢气浓度分布不均,侧墙顶部送风能使顶部堆积的氢气向下扩散,降低最大气体浓度;在墙角泄漏会由于墙壁的影响导致氢气堆积,对墙角局部通风尤为重要。研究结果可为氢燃料电池汽车专用车库的通风设计提供重要参考。     

重型车辆荷载下埋地天然气管道的安全分析

道路下的埋地天然气管道在重型车辆荷载通过时,管道受力一旦达到破坏强度就可能产生安全事故,造成天然气泄漏而引发燃烧与爆炸的危害,需要进行安全分析来判定重载车辆能否安全的通过道路运输。该文用理论计算和实验检测的方法综合起来分析埋地管道的相关力学参数,然后与管道自身的强度参数进行比较,从而判断埋地管道是否破坏。通过实例验证的方法说明了该方法在类似的项目分析中具有适用性和操作性,并提出了分析方法应用的初始条件。该方法可以作为判断埋地天然气管道在重载车辆作用下的一种安全评价方法,在条件允许的情况下可以利用数值模拟的方法进行比较印证,从而得到更为可靠的判断结论。同时,该方法也为埋地天然气管线在重载作用下的保护提供了基础资料,可以在此指导下更有效的保护天然气管线免受破坏。