D类干粉灭火系统调研报告

介绍国内外干粉灭火系统应用研究情况、D类干粉灭火在国内应用情况及国外灭火系统规范对D类干粉灭火系统的设计规定。提出在《干粉灭火系统设计规范》中对D类干粉灭火系统的处理意见。     

论干粉灭火系统的应用

简述了干粉灭火系统是卤代烷灭火系统的一种良好替代系统，干粉灭火技术是可信赖的灭火技术，概述了干粉灭火系统的组成，指出了生产厂家应提供给用户的必要图表，提出了工程应用设计计算方法。     

浅议三乙基铝催化剂干粉灭火系统设计

主要介绍了某聚乙烯装置三乙基铝催化剂区干粉灭火系统工程设计中干粉灭火剂选用、储存量及流量的计算、工艺流程的确定、控制原理及其具体设计参数。     

干粉灭火系统计算研究

研究了干粉灭火系统管道的管径、管道压力损失和防护区泄压口面积等关键参数的计算方法,给出了干粉输送管道管径、管道压力损失和防护区泄压口面积的计算公式。     

无管网悬挂式贮压超细干粉灭火系统设计

介绍无管网悬挂式贮压超细干粉灭火系统的灭火机理、适用范围、组成、启动方式、安装要求，与普通干粉灭火剂比较，并通过实例进行设计计算。     

浅析哈萨克斯坦石油化工装置消防设计

在石油化工装置的消防设计上,哈萨克斯坦与国内在设计规范及设计惯例等方面存在诸多差异。介绍了哈萨克斯坦石油化工装置消防规范,并从消防冷却水系统、泡沫灭火系统、蒸汽灭火系统、干粉灭火系统、自动气体灭火系统及消防用水量确定等方面,分析比较了哈萨克斯坦与国内石油化工装置消防设计规范及设计惯例的不同之处。     

氢氧化镁对磷酸二氢铵灭火剂性能的影响

在市售以磷酸二氢铵为灭火基料的ABC干粉灭火剂中加入氢氧化镁,利用自制实验装置对干粉灭火剂进行灭火性能、灭火温降实验测试。实验结果表明:氢氧化镁含量低于10%时,灭火剂灭火性能没有改善;氢氧化镁含量为20%时,干粉灭火效率、灭火后温降速率明显提高。     

石油化工企业变配电站及电缆敷设场所消防设施选择分析

对石油化工企业变配电站、电缆夹层、电缆隧道场产所火灾的原因进行分析,对油气田和石油化工场所的消防设施灭火原理及性能进行分析比较,提出了石油和石油化工企业的变配电站及电缆敷设场所消防设施选用ABC超细干粉灭火系统的可行性。     

超细磷酸铵盐干粉灭火剂研究

对Halon灭火剂的最佳替代品磷酸铵盐干粉灭火剂进行了研究。采用超音速气流粉碎机和特殊的表面处理方法对磷酸铵盐干粉进行超细化和硅化处理,制备出了平均粒径为7 28μm、比表面积为1 80m2/cm3的超细磷酸铵盐系列干粉灭火剂。用疏水保持率、吸湿率、抗结块性等指标对磷酸铵盐干粉灭火剂的主要性能进行了表征。灭火效果对比实验结果表明,超细化后的磷酸铵盐干粉灭火剂有效灭火次数由原来的2次增加到6次,有效灭火时间由原来的4s缩短到1s,其灭火效能约为普通型的4倍。     

EVA乳液生产装置消防初探

EVA乳液是乙烯与醋酸乙烯共聚物,醋酸乙烯为甲B类可燃液体,无色,有很浓的甜味,中度危害;乙烯为甲类易燃气体,无色,有淡甜味,轻度危害;EVA乳液是在加入保护性胶体(聚乙烯醇)和乳化剂(表面活性剂)的水溶液中由醋酸乙烯和乙烯聚合而成,EVA生产装置火灾类别为甲类,发生火灾时,需用雨淋系统做消防保护,同时设置消火栓、移动式干粉灭火器等辅助消防灭火系统。     

常用灭火剂灭火性能及原理

详细介绍了气体灭火剂、泡沫灭火剂、干粉灭火剂和气溶胶灭火剂等多种常用灭火剂的性能及灭火原理,并对其适用条件进行了说明。     

蛭石粉末及离子溶液改性后膨胀率和灭火有效性分析

为了研发高效干粉灭火剂粉体,提升干粉灭火剂的灭火效果,本文以蛭石粉为研究对象,采用NaCl、NaHCO₃、MgCl₂和KCl四类离子溶液对不同粒径的蛭石粉进行改性处理,并分析了原始蛭石粉末以及改性后的蛭石粉的膨胀率和表面微观结构。随后开展了ABC干粉灭火剂、未改性蛭石粉、MgCl₂改性蛭石粉、NaCl改性蛭石粉、KCl改性蛭石粉、NaHCO₃改性蛭石粉扑灭油池火实验,分析了灭火时间、灭火剂用量以及复燃情况。研究结果表明：粒径150 μm的蛭石粉末膨胀率最大,且经过改性的蛭石粉末的膨胀率要明显大于原始蛭石粉末,其中MgCl₂改性后的蛭石粉膨胀率最大,接近2.4左右;从灭火时间来看,灭火效果从低到高依次为ABC干粉灭火剂、未改性蛭石粉、MgCl₂改性蛭石粉、NaCl改性蛭石粉、KCl改性蛭石粉、NaHCO₃改性蛭石粉;从灭火剂用量角度可得出：改性蛭石粉灭火用量要明显小于未改性蛭石粉。其中,NaHCO₃改性蛭石粉用量与ABC干粉灭火剂用量相对接近。从复燃角度来看,膨胀蛭石粉末的密度较小,可长时间悬浮在油品表面,有效阻止复燃,效果明显优于传统的ABC类干粉灭火剂。     

热、冷气溶胶灭火技术在汽车固定式灭火装置上的应用

简单介绍了气溶胶灭火剂的灭火机理、分类及应用现状,分析了汽车火灾的原因,着重探讨了两种新型汽车用固定式灭火装置即热气溶胶灭火装置与超细干粉灭火装置之间制备、性能等方面的区别,展望了热气溶胶产品在汽车火灾方面的应用前景.     

化学组分对干水灭火剂流动性与保水性的影响

干水（dry water）是微水滴颗粒被纳米级疏水性二氧化硅颗粒包覆层封装形成的、整体呈固体粉末状的粉体材料,其颗粒内含水量可高达98%,内部水分可以通过高温蒸发和外力挤压作用释放出来,是很有潜力的特种灭火新型材料。干水灭火剂的核心是功能性化学灭火组分,本文设计并制备了包覆不同功能性化学灭火组分的系列干水灭火剂,并测定表征了所制备干水灭火剂的粒径分布、流动性与保水性,研究了不同功能性化学灭火组分对干水灭火剂储运性能的影响。结果表明,不同功能性化学灭火组分的加入能够在一定程度上提高干水材料颗粒的流动性和保水性,其中磷酸二氢铵干水的流动性最优,氯化钠干水的保水效果最好。研究对干水灭火剂的制备、储运与使用具有重要意义。     

Experimental assessment on LPG fire extinguishing properties of three chemical powders before and after milling action

The extinguishing performance of three dry chemical powders (DCPs) was investigated through a lab-scale suppression system for liquefied petroleum gas (LPG) fire. The magnesium hydroxide (Mg(OH)₂ ), sodium bicarbonate (NaHCO3 ), and commercial ABC − MAP powders are used to prepare two groups of samples: raw samples and milled samples. The effect of milling action on the properties of DCPs, such as the bulk density, microstructure, particle size, thermal decomposition, and the extinguishing performance, is analyzed. The density test revealed that the bulk density increased after milling, and the Mg(OH)₂ had a lower density than the other powders. The microstructure analysis showed that the milled powders had a smaller particle size and more regular shapes than raw powders. The thermal analysis demonstrated that the powder decomposition process was somewhat similar with a slight difference in initial decomposition temperature and degradation rate. The fire tests proved that the extinguishing efficacy greatly improved after the samples were milled. Moreover, the experiments indicated that the milled Mg(OH)₂ was superior in fire extinguishing to the other samples with shorter extinction time and less agent quantity consumed. Based on the results, it can be inferred that the milling action has a significant influence in enhancing the extinguishing mechanisms' efficiency of DCPs.     

Fire suppressing performance of superfine potassium bicarbonate powder

Fire suppression effectiveness of a new kind of dry powder based on potassium bicarbonate was studied in this paper. The powder consisted of superfine potassium bicarbonate and some organic and inorganic additives, which was denoted as ‘K‐powder’. The physical and chemical characteristics of the K‐powder were characterized by a series of techniques of X‐ray diffraction, scanning electron microscopy, Fourier transforms infrared (FTIR) and thermal gravity analysis, etc. Performance of the new potassium‐based powder in fire suppression was studied by laboratory‐scale experiments, which exhibited much superior fire suppression efficacy than that of the commercial bicarbonate powder. Such improvements could be reasonably ascribed to the special chemical composition, microstructure and radiation effect on the mechanisms. The preparation, fire suppression and possible fire‐extinguishing mechanisms were studied in detail. Copyright © 2010 John Wiley & Sons, Ltd.     

灭火系统节点压力计算方法

消防工程设计中,节点的压力计算较难掌握。采用例题演示计算的方法,介绍了液体灭火系统、二氧化碳灭火系统和干粉灭火系统管道节点压力的计算方法,可供消防工程设计人员参考。     

Study on the relationship between the particle size distribution and the effectiveness of the K‐powder fire extinguishing agent

The relationship between the particle size distribution and the extinguishing effectiveness of the new K‐powder fire extinguishing agent has been studied experimentally, to explore the reason of the great extinguishing efficiency exhibited by the new K‐powder fire extinguishing agent on Class B fire (liquid fuel fire). The results of the experiment showed that the extinguishing effectiveness increased along with the decrease of the particle size distribution. In addition, a sharp discontinuity appeared around the limiting size, about 40 μm. The powder with the particle size below 40 μm exhibited highly effective extinguishing with the minimum effective extinguishing concentration C_xr = 23 g·m^?3, while the powder with the particle size above 40 μm exhibited little fire extinguishing efficiency. Compared with other fire extinguishing agents produced by different substances, the new K‐powder fire extinguishing has the bigger limiting size. That means, in the same particle size distribution, the new K‐powder fire extinguishing agent contains more highly effective powder than others contain, and is more effective.