Deposition and Resuspension of Selected Aerosols Particles on Electrically Charged Filter Materials for Respiratory Protective Devices

The primary aim of the study was to analyse the non-steady state of filtration for selected electrostatic filter materials designed for use in respiratory protective devices. The obtained results showed that the filtration process in electrostatic filters was dependent in the main on the following factors: type of the filter material, electrostatic field strength of the material, and the charge of the aerosol.

To a lesser degree the filtration process depended on the sign of the charge and the relative humidity of the air. A significant correlation was found between the increase in the penetration and the decrease in breathing resistance while the filter was being loaded.

The effect of resuspension (tearing off and re-deposition of dust agglomerates inside the filter) on the filtration process very significant. It was also observed that under certain conditions electrostatic filter materials lost their protection properties.     

油库静电危害综合控制方法的研究

油库是易燃、易爆的危险场所,当达到油气爆炸极限及产生静电放电时,极易发生油品静电灾害.通过对液体带电机理、油品能够产生静电的几种形式、影响静电电位因素以及静电能够引发火灾的几个条件的分析,提出了油库控制静电危害发生的措施.     

Reaction zone structures and propagation mechanisms of flames in stearic acid particle clouds

Reaction zone structures and propagation mechanisms of two representative flames established in stearic acid (CH₃(CH₂)₁₆CO₂H) particle clouds have been investigated. The reacting zone structure was examined by using a micro-electrostatic probe and a high-speed schlieren system. A distinct difference was observed in the ion current fluctuations recorded across the two representative flames propagating through the clouds of the same total mass density of particles and different mass densities of the particles smaller than 60 μm in diameter. When the mass density of smaller particles was high, a single peak was recorded in the ion current fluctuation. On the other hand, when the mass density of smaller particles was low, multi-peaks of various heights and widths were recorded. In the former case, the single peak was considered to be attributable to a unitary and a relatively thin flame started burning in vapor generated by the evaporation of smaller particles in the preheat zone. The flame propagation mechanism in this case was inferred to be similar to that of a usual hydrocarbon–air premixed flame, although the reaction zone thickness is much larger than that of the premixed flame. In the latter case, the multi peaks of various shapes were considered to be attributable to strong combustion at blue spots far behind the schlieren front. The flame propagation in this case was inferred to be supported by the heat release due to combustion at the blue spots.     

基于碳纤复合材料的可重复使用运载器静电防护研究

目的研究可重复使用运载器的静电防护方案。方法针对可重复使用运载器特点,以及飞行期间遭遇的空间静电放电环境,基于空间静电带电数学模型,计算出运载器表面材料带电离子的静电充电电位。在此基础上,分析复合材料静电特性,提出静电防护层与电气设备等电位共地方案。结果该方案采用碳纤维复合材料作为静电防护层,与大截面积的接地母线相连,为运载器电气设备提供低阻抗、大电荷容量的等电位地。结论该方案能够有效抵御静电产生的干扰,为运载器电子设备提供可靠、安全、抗干扰的电磁环境。另外,该方案工艺实现简单,大大减轻了运载器的设计质量。     

新型节能电源控制技术在电除尘器上的应用

对当前电除尘器的主流节能技术进行了综合分析和论证,指出应通过先进的电源控制产品优化除尘器运行方式来实现除尘器的节能高效运行,利用高频电源技术达到电除尘器节能减排的目的。     

华电新乡宝山电厂660MW机组除尘器提效改造

华电新乡宝山电厂660MW机组配套电-袋复合除尘器是国内成功投运的大型电-袋复合除尘器。该机组原配套2台双室四电场电除尘器,由于各种原因导致投运后排放一直超标。2009年4月改造为电-袋复合除尘器,取得良好效果。     

浅谈袋式除尘器废旧滤袋的处置

袋式除尘器是目前世界上应用最多、最为成熟的除尘设备。由于其除尘效率高、结构简单、适应性强、工作稳定、可回收干料等特点已广泛应用到各行各业中。而随着袋式除尘器的广泛应用,大量破损的废旧滤袋的处置也成为难以解决的棘手问题。本文分析了国内滤袋市场现状以及废旧滤袋难以有效处置的原因。     

高炉煤气高效曲板脱水装置的试验研究

提出了一种降低机械水含量的新型脱水装置,针对曲板脱水装置内两相流动复杂的问题,在改变结构和运行参数的情况下对曲板脱水装置的性能进行了试验研究,探讨了各影响因素对脱水效率和压力损失的影响。试验结果表明:曲板脱水装置的最佳气流速度为1.75～2.25 m/s,曲板间距为5～7.5 mm,斜板长度为200～250 mm,液气比为0.2～0.25 L/m3,水雾粒径为100～500μm时,可以获得最高脱水效率和最小压力损失。     

静电油烟净化器对餐饮油烟中醛酮类VOCs的去除

利用2,4-二硝基苯肼（DNPH）硅胶管采集了9家餐饮企业静电油烟净化装置处理前后的醛酮类VOCs样品,并采用高效液相色谱（HPLC）进行分析.结果表明,9家餐饮企业处理前后的油烟中醛酮类VOCs浓度范围分别为419.5~3372,415.8~2934μg/m³,经过基准风量折算后的浓度分别为783.4~3761和541.7~2997μg/m³,VOCs排放浓度与烹饪方式、实际使用灶头数和排风量有关.从排放的醛酮类VOCs的种类来看,C1~C3化合物的浓度占检测到的总羰基的66%以上,且甲醛占比最高,其次是乙醛;C4~C8化合物的含量相对较低.静电式油烟净化器对醛酮类VOCs的平均净化效率为31.82%,最高可达69.14%,其中对甲醛的净化效果最佳,平均为35.21%,最高达80.10%.复合式静电油烟净化器的净化效果要稍好于单一静电油烟净化器.     

气力输送化工粉体静电带电影响因素试验研究

采用自建全尺寸粉体静电试验系统,以聚丙烯颗粒为试验介质物料,测试了气力输送过程中物料质量流量、输送气体流量以及离子风消电器对聚丙烯颗粒静电带电量的影响规律。结果表明:气力输送粉体物料时,粉体颗粒与管壁碰撞是影响颗粒带电的主要因素之一,导致颗粒带电量随颗粒质量流量降低和气体输送流量增加(风速增大)而增大。提高质量流量、降低输送气体流量并使用离子风静电消除器,是降低气力输送物料静电危害风险的重要措施。