多功能球形爆炸容器研究

20L球形爆炸容器是通用的研究气体、可燃液体蒸气和粉尘等爆炸参数的重要仪器。本文以现有的压力容器标准为依据,将爆炸瞬态载荷转换成等效静态载荷,运用动力系数法,研究出了一种可用来做气体、可燃液体蒸气和粉尘爆炸实验的球形爆炸容器。用此球形爆炸容器进行液压实验和爆炸极限实验,实验得到甲烷的爆炸下限为4.5%,上限为14.0%;乙醇蒸气爆炸下限为2.5%,上限为15.0%;10μm镁粉粉尘爆炸下限为45g/m3,实验所得数据与文献中的差别不大。结果证明本文所设计的多功能球形爆炸容器科学合理,能够满足爆炸实验要求。     

废弃硒鼓残留墨粉的爆炸参数研究

为研究废弃硒鼓中残留墨粉的爆炸特性,对hpQ2612A型墨粉的物化性质进行了分析,并实验测试其爆炸参数,判断墨粉的爆炸敏感性和强度,从而指导硒鼓资源化工艺设计中的爆炸预防和防护措施.结果表明:墨粉粉尘具有爆炸性,其爆炸压力中等,爆炸指数较大,爆炸下限较低;墨粉粉尘层不易发生自燃,在250℃时熔化,高于400℃时不着火;墨粉粉尘云着火温度较高,但粉尘云最小点火能量较低.说明墨粉爆炸敏感度较高,爆炸猛烈度也较大.     

酒精蒸气-烟草粉尘耦合体系燃爆猛度特性研究

基于改进的20 L球粉尘爆炸试验装置,探究了酒精蒸气体积分数、烟草粉尘质量浓度及环境温度对酒精蒸气-烟草粉尘耦合体系燃爆猛度的影响规律。结果表明:加香烟草粉尘相较于烘丝烟草粉尘的爆炸压力与爆炸压力上升速率更高;酒精蒸气不仅会增强加香烟草粉尘的可燃性,而且会使其爆炸上限升高;耦合体系的酒精蒸气体积分数低于50%酒精爆炸下限(LEL)时,其爆炸压力与爆炸压力上升速率增幅较缓,而高于50%LEL时,增幅迅速攀升;升高环境温度对耦合体系燃爆猛度有明显的促进作用,在低温阶段(30～40℃)尤为显著。     

初始温度对湿法成型硫磺燃烧爆炸特性影响的试验研究

为了研究初始温度变化对湿法成型硫磺粉尘燃烧爆炸特性的影响,通过对初始温度分别为35℃、 45℃、 55℃、 65℃、 75℃的硫磺粉尘试样进行测试,发现随着初始温度的上升硫磺粉尘的粉尘云最低着火温度,粉尘云最小点火能逐渐降低;随着初始温度的上升硫磺粉尘的爆炸下限和粉尘层最低着火温度不发生变化。随着温度的升高,硫磺粉尘的燃烧爆炸危险性增加,因此在气温较高的夏秋季节要提高硫磺粉尘燃爆的防护等级。     

基于因子分析法综合评估粉尘爆炸危险性

本文选取最小点火能、爆炸下限、粉尘云最低着火温度、最大爆炸压力、最大爆炸压力上升速率、最大爆炸指数和粉尘层最低着火温度这些特性参数,利用多元统计方法中的因子分析法,对小麦淀粉、玉米淀粉、豆粉、石松子粉、铝粉、镁粉、褐煤粉尘、硫磺粉尘进行分析与评估。结果表明,粉尘爆炸参数的信息重叠度大,抽取出的两个公共因子的累积贡献率可达到83.799%。以公共因子1和公共因子2的贡献率为权数,构造综合评估函数;对以上几种粉尘的爆炸危险性进行了排序。     

粒径对硫磺燃烧爆炸特性影响的试验研究

针对湿法成型工艺硫磺粉尘进行燃烧爆炸特性参数测试,对目数范围介于16~35目,35~60目,60~80目,80~100目,100~120目,120~160目,160~200目,200目筛下八组硫磺粉尘的:粉尘层着火温度、粉尘云最低着火温度、粉尘云最小点火能以及爆炸下限四个参数进行了测试,确定了不同粒径分组硫磺粉尘的燃烧爆炸参数。为硫磺湿法成型系统硫磺粉尘浓度监控标准的制定提供依据。     

常见粮食粉尘理化特性的研究

对常见粮食粉尘的物理、化学特性和爆炸特性进行了研究和分析,得出了常见粮食粉尘的粒度分布曲线.粮食粉尘具有较大的空隙率,而且是一种流动性较差的物质,它在运输、流动、清理过程中易和粮粒分离.小麦、玉米粉尘中的无机成分约占一半左右,大豆的约为1/6,小麦、玉米粉尘中有机成分主要是碳水化合物.进口粮食粉尘的层状、云状、着火温度、最小点火能、爆炸下限浓度明显低于国产粮食的,尤其是最小点火能和爆炸下限浓度低2倍多,导致这一差别的主要原因是进口粮食粉尘中有机物含量远远高于国产粮食粉尘,可见粮食粉尘的点燃灵敏度和其他爆炸特性参数的大小基本由粉尘中所含的有机物含量决定.     

运用本质安全原理预防煤粉爆炸

旨在将本质安全原理与粉尘爆炸(以煤粉爆炸为例)的风险控制联系起来。利用20 L球形爆炸装置的标准测试方法测试煤粉及煤粉-CaCO3混合物的爆炸下限、最大爆炸压力、压力上升速度等爆炸特性。基于本质安全基本原理和试验结果,讨论预防煤粉爆炸的各种基本方法,并重点阐述本质安全原理与粉尘爆炸影响因素、不同的预防方法、过程设备的选择等之间的关系,对已制定的爆炸风险控制措施进行完善和补充。     

高硅铝合金粉尘云燃爆特性研究

通过开展硅质量分数25%高硅铝合金粉尘燃爆特性研究,揭示了硅质量分数25%高硅铝合金粉尘的最小点火能、最低着火温度、爆炸下限和最大爆炸压力。研究结果表明,在实际生产中要防止高硅铝合金粉尘云与雷电、静电、生产中摩擦或碰撞所产生的火花等能量源接触,避免达到高硅铝合金粉尘云的最小点火能0.1～0.2 mJ而引发爆炸事故;要防止出现明火与发热设备热表面温度达到高硅铝合金粉尘云最低着火温度960℃;对高硅铝合金生产场所、工艺设备等进行抗爆设计时,约束爆炸压力措施承受最大爆炸压力的冲击至少要在0.525 MPa或以上。     

粉尘爆炸特殊风险的辨识、评价和控制

针对粉尘爆炸的特殊风险,以粉尘爆炸特征参数为基础,从爆炸环境形成和13种点火源出现可能性两个方面提出了风险辨识方法,突出了爆炸下限和最小点火能在粉尘爆炸风险辨识中的重要性,并以面粉厂制粉系统为例进行了点火源危险性的辨识分析。对控制粉尘爆炸的最新防护方法进行了概括和分析,总结并分析了常用粉尘爆炸预防和防护措施及相关技术装置,指出了对应的使用条件和特点。     

油页岩含氧干馏工艺流程爆炸极限分析

根据干馏工艺流程配入适量氧气,可以降低载热气体需要预热的温度,以实现低能耗、易于工业生产的特点,设计了一套新型的有氧干馏工艺流程。有氧干馏工艺因其过程中存在可燃性混合物,有发生爆炸事故的可能性,通过实验对所收集的不同温度下的干馏气体的成分与含量进行了分析,结合爆炸极限理论,对该有氧干馏工艺流程的不同温度、不同惰性气体含量条件下可燃气体爆炸极限进行了分析计算。结果表明,可燃气体的浓度在整个反应升温过程中始终没有进入爆炸危险区域,说明该实验装置不具备爆炸危险性;对干馏工艺流程中氧气的输入量的控制,可以防止该工艺流程的火灾爆炸的发生。     

Study on the preparation of novel FR-245/MCM-41 suppressant and its inhibition mechanism on oil shale deflagration flame

Oil shale development is of great significance because oil and gas resources are scarce. Research on the prevention of oil shale dust explosion is particularly important for guaranteeing the safe development and utilization of oil shale resources. In this work, the flame morphology and velocity of oil shale dust with and without MCM-41 or FR-245 were compared. Furthermore, the novel green FR-245/MCM-41 inhibitor was prepared by jet mill method and used in oil shale dust explosion for the first time. The best ratio of FR-245/MCM-41 for flame inhibition was obtained, which was 9: 1. The pyrolysis oxidation behavior of oil shale before and after adding FR-245/MCM-41 was analyzed and compared by FWO and KAS methods, respectively. The results showed that the activation energy calculated by FWO and KAS methods greatly increased after adding FR-245/MCM-41, which increased by 95.36% and 115.15% than that before adding inhibitor, respectively. Significantly, the activation energy is particularly high for two methods when α between 0.2 and 0.6, due to that MCM-41 and FR-245 coexisted to limit the oxidation of oil shale. For α between 0.7 and 0.9, the activation energy is still high because of the existence of MCM-41. Combining the oil dust flame propagation behavior with the characterization results before and after explosion, the physical-chemical synergy mechanism of oil dust flame propagation inhibition was revealed.     

热爆炸理论在粉尘爆炸机理研究中的应用

笔者对粉尘爆炸的几种机理进行了简要分析 ,认为粉尘爆炸是由热爆炸引起的。在对粉尘燃烧过程作了较为合理的假设后 ,将热爆炸理论中均温系统的热爆炸判据 ,应用于粉尘爆炸中 ,得出了爆炸下限与粉尘粒径呈线性关系的结论 ,且与实验符合 ,并推导出粉尘的热爆炸判据。结果表明 :用热爆炸理论来解释粉尘爆炸机理是可行的。     

储、转运粮食系统除尘粉尘回流安全性分析

对储存及转运粮食系统除尘粉尘回流问题进行了回顾和评述 ,对天津港散粮站日常处理主要粮食品种伴生粉尘进行了物性分析和粉尘爆炸性测试 ,并结合生产工艺过程进行了设备内部实际粉尘浓度的测试 ,在此基础上得出 :除尘粉尘具有爆炸的危险性 ;爆炸下限较高 ,有利于控制粉尘浓度在爆炸下限以下来预防粉尘爆炸 ;除尘粉尘回流工艺在无粉尘沉积的情况下是安全的。     

Analysis and assessment of the Qingdao crude oil vapor explosion accident: Lessons learnt

A devastating crude oil vapor explosion accident, which killed 62 people and injured 136, occurred on November 22, 2013. It was one of the most disastrous vapor cloud explosion accidents that happened in Qingdao's storm drains in China. It was noted that blast overpressure and flying debris were the main causes of human deaths, personal injuries and structure damages. Two months after the accident, it was reported that there were three contentious issues in the investigation report. First issue was the discrepancy between the temperature of the crude oil vapor explosive limits which were measured by the investigation panel and the temperature reported by the local fire department. Second issue was the contradiction between the upper explosive limit and vapor pressure of the crude oil vapor. The last issue was the location of the ignition source which led to the explosion.In the present study some specific features of this accident and various causes led to the explosion, high casualties and severe damages were analyzed. Three contentious issues in the official investigation report were investigated and tested in detail. The first element tested was the explosive limits and limiting oxygen concentration of the crude oil vapor at different temperatures. Based on theoretical analysis and field investigations, the last two elements in the report were analyzed from multiple perspectives. Based on the TNO Multi-Energy model and PROBIT equations, damage probability of affected people at the leaking site was also estimated. The investigation concluded with a result that precautions need to be taken to prevent flammable gas explosions in the drainage systems. Key steps were explicitly discussed for improving the hazard identification and risk assessment of similar accidents in the future.     

The effect of admixed material on the minimum explosible concentration of oil shale

The minimum explosible concentration (MEC) in the air atmosphere at the boundary between an explosion and no explosion in a dust cloud, has been investigated for several particle sizes of oil shale and for mixtures of oil shale and inert powder of different particle size. Limestone, stone dust and coarse particle size of oil shale were used as inert materials. Measurements were made in a standard small vertical tube apparatus. The results obtained indicated that the minimum explosible concentration is dependent on the particle size, i.e., values of MEC decrease with a decrease in the size of the particles. Below 70 μm, values of MEC become almost constant. Admixture of limestone as low as 5% to oil shale is sufficient to reduce the MEC values significantly.     

碳纤维复合材料粉尘爆炸强度特性研究

碳纤维复合材料是应用于航天、航空领域的高性能材料之一,对于该材料的粉尘爆炸特性还未有相关研究报告。为了研究碳纤维复合材料粉尘的爆炸强度特性,本文采用20L球形粉尘爆炸测试实验系统开展了相关实验研究。实验测得碳纤维复合材料粉尘爆炸下限浓度为50g/m 3,最大爆炸压力为0.48MPa。在测试浓度范围内,最大压力上升速率和爆炸指数均随浓度的增大而变大。另外,在其爆炸强度特性研究的基础上,对产尘车间的环境风险进行了初步辨识,提出了相应的防护措施。本文的研究成果对此类碳纤维复合材料粉尘的工业防护具有实际的指导作用,对于该粉尘的爆炸机理的深入研究也具有一定的参考价值。     

EVA树脂粉尘/甲烷/空气杂混物爆炸特性

在20 L爆炸实验装置中,开展了3种不同中值粒径的EVA树脂粉尘/甲烷/空气所组成的杂混物爆炸特性研究,探究了甲烷浓度对粉尘爆炸下限、最大爆炸压力的影响。结果表明,尽管添加的甲烷气体浓度低于爆炸下限,仍使得粉尘爆炸下限得以降低,粒径较大的EVA III粉尘,当甲烷体积分数为1%时,爆炸下限降低约25%;粒径较小的EVA I粉尘,当混入甲烷体积分数为4%时,爆炸下限则降低80%;甲烷体积分数每增加1%,可燃粉尘最大爆炸压力上升约10%,但对于粒径较小的EVA I粉尘,当甲烷体积分数为4%时,最大爆炸压力的上升呈现突变趋势,上升近50%。