双层炉排锅炉如何正确操作

根据双层炉排锅炉的特点，从锅炉的安装、点火、燃烧的调节、调风、停炉和调火六个方面阐述了正确操作的方法。     

粉尘云最小点火温度测试实验系统设计

通过对Godbert -Greenwald恒温炉分析与改造 ,设计了粉尘云最小点火温度实验装置 ,并建立了相应的测试系统。调试结果表明 ,该实验系统扬尘均匀性、温控精度及结果可重复性能良好     

加强安全管理 提高安全生产水平

搞好安全生产 ,防止事故 ,必须从加强企业的安全管理入手。本文提出采用有效的安全管理方法 ,建立和实施职业安全卫生管理体系标准 ,健全各项安全管理制度并狠抓落实 ,使企业逐步走向安全管理标准化     

On the divergence criterion for runaway detection: Application to complex controlled systems

It is well-known that, for certain values of the operative parameters influencing the dynamic behavior of a chemical reactor, a phenomenon known as thermal runaway (that is, a loss of the reactor temperature control) may arise. Such a situation can be really dangerous because above a certain threshold temperature value unwanted side reactions or, worse, decompositions of the reacting mixture may be triggered evolving high amounts of flammable or toxic gases that can cause reactor pressurization and, eventually, its explosion. For this reason, since the beginning of the previous century a number of studies concerning the prediction of the so called runaway boundaries has been carried out. In this work, a modified version of the divergence criterion for runaway detection, originally developed by Zaldívar and co-workers, is presented. Such a modified divergence criterion is capable of treating whatever type of complex controlled reacting system (taking into account not only temperature control but also dosing strategies) and its reliability has been demonstrated for isoperibolic semibatch reactors using literature experimental data concerning the nitration of 4-Chlorobenzotrifluoride in mixed acids and the nitric acid oxidation of 2-octanol to 2-octanone and further carboxylic acids.     

小麦淀粉粉尘爆炸特性参数的研究

采用哈特曼管式爆炸测试装置和20L球爆炸测试装置对小麦淀粉粉尘爆炸特性参数进行评估,对粒度小于75μm的样品的爆炸危险性参数进行测试,得出了一定条件下的小麦淀粉对静电火花的敏感程度以及其爆炸的猛烈程度,进而对其爆炸危险性程度进行分级。结果表明,温度在25℃,喷粉压力为0.70MPa,小麦淀粉的最小点火能量在40~80mJ;在点火能量为10 kJ时,最大爆炸压力为0.60MPa,最大爆炸指数为7.87MPa.m/s,其粉尘爆炸危险性为Ⅰ级。     

焊接防护具抗热穿透性能测试仪的研制

焊接防护具是指一种保护佩戴者免受由焊接或相关作业所产生的有害光辐射及其他特定有害因素的装置。它是从事焊接与热切割作业人员必备的个体防护装备。抗热穿透性能是表征焊接防护具产品质量和安全性能的最重要技术指标之一。然而,如何快速、便捷、节能、准确地对焊接防护具抗热穿透性能进行检测,是迫切需要解决的技术难题。本文在简要分析国内外眼面部防护标准中抗热穿透性能技术要求和测试方法的基础上,提出了一种测试焊接防护具抗热穿透性能的方法,并成功研制了焊接防护具抗热穿透性能测试仪。     

不同条件下6-APA粉体爆炸最小点火能测试研究

6氨基青霉烷酸（6-APA）是生产阿莫西林的重要中间体,在生产过程的离心机分离及干燥等环节存在粉体燃烧爆炸的危险。利用Hartmann管式粉尘最小点火能测试装置,研究6-APA干粉状态及丙酮存在环境粉体最小点火能变化规律。实验结果表明,6-APA粉体在分散质量为0.6g时,最小点火能为14mJ,参照VDI2263的规定,属于一般着火敏感性粉尘。向粉体中加入丙酮溶剂模拟实际生产环境,实验结果显示粉尘云最小点火能下降明显,且混合物着火能力增强。质量为1g的6-APA粉体与0.5mL丙酮溶剂配比条件下,混合物分散质量为0.6g时,最小点火能为6mJ,在此环境中混合粉体属于特别着火敏感性粉尘。实验结果阐明了6-APA在丙酮存在环境条件下混合粉体燃烧的爆炸危险性,为采取相应的爆炸防护措施提供了实验依据。     

点火提前角对焦炉气天然气混燃发动机燃烧特性的影响分析

为了研究不同点火提前角对焦炉气与天然气混燃发动机燃烧特性的影响,对一台6缸焦炉气发动机,运用CATIA建立其燃烧室模型。在相同的条件下,运用CFD分析软件研究了6种点火提前角（θig）下焦炉气与天然气发动机的燃烧特性。模拟表明:随着θig的提前,缸内的压力、温度、NO生成量的峰值都会升高且提前,当θig推迟到-12 ℃A以后时,出现严重的后燃现象,使得排放温度升高;当θig提前到-25 ℃A之前时,NO的生成量和缸内流速迅速增加,快速燃烧在压缩上止点之前10 ℃A范围内,发动机做负功;当θig为-15 ℃A时,虽然NO的生成有所增加,但是增加的不是很大,并且压力、温度、快速燃烧都在做功行程接近上止点的位置。     

Prediction of dust cloud minimum ignition energy for organic dusts from modified hartmann tube data

The modified Hartmann tube apparatus is recognized to give realistic or safe indications of dust explosion violence. Evidence is presented that results from this apparatus can also be used to indicate minimum ignition energy. Published data show a correlation between minimum ignition energy and minimum explosible concentration, which is refined by also taking into account explosive violence. An empirical model has been derived, relating minimum ignition energy to minimum explosible concentration and explosive violence. The model allows estimation of probabilities of minimum ignition energy falling below specified values, such as those recognized as of practical importance by the relevant British Standard. A limited test of the model suggests that it can be applied to modified Hartmann tube data. It is anticipated that the model will be valuable as a screening tool, especially in the early stages of development of a project.     

Shock-induced dust ignition in curved pipeline with steady flow

The ultimate objective of the research outlined in this paper is to determine the conditions governing shock-induced ignition of dusty flows in curved pipelines using analytical and computational approaches. The results of numerical simulation indicate that ignition of two-phase flows in curved channels is mainly conditioned by the shock-induced flow and is not very sensitive to the flow structure in front of the shock wave. The calculations of nonreactive shock propagation in the quasi-steady two-phase flow and in the uniform quiescent dust suspension revealed significant differences in the postshock flow structure downstream the channel corner. Nevertheless, ignition occurred in the region where the predominant role was played by reflected shock waves, i.e., in the vicinity to the channel corner. The results call for further studies dealing with shock-induced ignition and explosion build-up in curved channels.