我国黑色冶金烧结厂除尘技术的进展

随着烧结工艺技术水平的不断提高,作为环境保护、劳动保护和安全生产所必需的烧结除尘技术取得了相应的发展。此外,由于一批技术先进、净化效率高、运行可靠的除尘器研制成功、批量生产和投入使用,为烧结除尘提供了性能良好的净化设备。在近期的设计中,烧结废气除尘系统改变了传统的应用多管除尘器的方式而采用高效的静电除尘器;在系统布置方面改变了过去的分散式除尘方式而采用按粉尘性质分片大集中除尘方式,并选用高效的静电除尘器和袋式除     

65 t/h煤粉锅炉除尘脱硫系统技术改造

对某电厂65 t/h煤粉锅炉水膜除尘器进行了旋流板塔脱硫除尘一体化改造研究,使其在保持原有水膜除尘器特点和功能的情况下增加其脱硫功能,提高除尘效率.通过本改造工程设计实例,探讨了除尘脱硫装置的选择及影响除尘脱硫系统效率的参数.改造实际运行表明:改造方案是经济的,技术上是可行的,脱硫效率80%以上,除尘效果达99%以上.水膜旋流板除尘脱硫系统是一种高效率、改造简单、运行可靠的湿式除尘脱硫系统.     

新型高效袋式除尘器在矿山除尘系统的应用研究

基于布袋除尘器运行过程中具有容易粘袋、滤料使用寿命短等缺点,设计研究了一种采用特殊滤料加工工艺和表面处理技术的新型高效袋式除尘器,该除尘器具有阻力小、体积小、除尘效率高、滤料强度高、憎水性能好、使用寿命长等优点。以安徽刘塘坊矿业有限公司除尘系统为应用研究对象,证明了该新型高效袋式除尘器在矿山除尘系统的应用效果,具有很好的经济效益和环境效益。     

低压脉冲袋式除尘器在硅铁电炉烟气中的应用

介绍了低压脉冲袋式除尘器在6300 kVA半封闭式硅铁电炉烟气除尘系统中的应用,通过对铁合金半封闭式硅铁电炉烟气性质的分析,对除尘系统在运行过程中出现的问题以及解决方案进行了分析和阐述,最后指出低压脉冲袋式除尘器在半封闭式硅铁电炉除尘系统中使用时应该注意的问题。     

转炉烟气袋式除尘系统节能降碳途径

分析了转炉烟气袋式除尘系统能耗的影响因素,提出了袋式除尘系统减污降碳技术途径,重点对袋式除尘器运行阻力的构成、分布和降阻措施进行了阐述,设计了转炉烟气袋式除尘器最小阻力的理想指标。可为转炉炼钢烟气袋式除尘节能降碳和超低排放提供借鉴。     

布袋除尘器在烧结机机尾除尘中的应用

介绍了用旋风除尘器、布袋除尘器组成的二级串联除尘系统在小型烧结机机尾烟气除尘中的实际应用。实际运行结果表明，该系统运行可靠，除尘效率高，系统出口含尘浓度达到了国家允许的排放标准，并针对相关问题进行了探讨。     

涟钢烧结厂成品仓除尘系统的改造

涟钢烧结厂成品仓扩建,老除尘器处理能力有限,无法达到除尘效果,必须改造.长袋低压脉冲袋式除尘器具有清灰能力强,喷吹压力低,过滤风速大,运行能耗低,换袋方便,维修简单等特点,运用于此除尘系统中,取得了良好的除尘效果.     

袋式除尘器和静电除尘器在电厂除尘系统中运用的性能对比分析

针对目前火电厂除尘系统应用现状和当前环保要求,通过对袋式除尘器和静电除尘器在火电厂燃煤锅炉除尘系统中的应用,对袋式除尘器和静电除尘器在技术性能上的差异作了简单的对比分析,以指导除尘器在目前火电厂燃煤锅炉除尘系统中的具体应用。     

XCY型高效旋风除尘器的应用

陕西新秦造纸厂SZL—10—13型工业锅炉于1987年9月起运行,使用西安冶金建筑学院研制的XCY型组合式旋风除尘器,至今已有一年多时间,效果良好。经陕西省环境保护中心测定结果见表1。该厂反映该除尘器结构紧凑,除尘效率高,较彻底地解决了因煤灰满天飞影响纸张质量及污染环境的老大难问题。陕西宝鸡水泥厂将XCY型旋风除尘器分别用于粘土烘干机、生料磨机、熟料磨机两级除尘系统的前级除尘,尽管入口风速低,仍然保持除尘效率高的特点,为该厂除尘系统改造达到国家排放标准的要求起到了关键作用。宝鸡市环境监测站对这几个除尘器测定结果见表2。     

济源钢铁厂混料系统废气及其治理

对济钢混料系统废气的来源及特性进行论述。采用水雾除尘器加以治理。该除尘器具有投资少操作简便,运行可靠,除尘效果稳定的特点。     

CFD Simulation of the Dispersion of Binary Dust Mixtures in the 20 L Vessel

There are at least two main requirements for repeatable and reliable measurements of flammability and explosibility parameters of dusts: a uniform dispersion of solid particles inside the test vessel, and a homogeneous degree of turbulence. In several literature works, it has been shown that, in the standard 20 L sphere, the dust injection system generates a non-uniform dust cloud, while high gradients characterize the turbulent flow field. In this work, the dust dispersion inside the 20 L sphere was simulated for nicotinic acid/anthraquinone mixtures (with different pure dust ratios, while keeping the total dust concentration constant) with a validated three-dimensional CFD model. Numerical results show that the fields of dust concentration, flow velocity and turbulence are strongly affected by both diameter and density of the pure dusts. These different dust properties lead to segregation phenomena with the formation of zones richer in one component and leaner in the other one and vice versa, and also result in preferential paths for the solid particles inside the sphere. Overall, the obtained results highlight the need for developing a dust injection system able to overcome the shortcomings of the actual one even when testing dust mixtures.     

焦化厂原煤破碎车间粉尘污染治理的研究与设计

对原煤破碎车间粉尘污染的特点进行了分析:对采用新型移动式颗粒床除尘器的可行性进行了论证;并对除尘系统进行合理设计,取得了满意的效果。     

制定粉尘卫生标准的新趋势——介绍欧洲的经验并提出几点建议

介绍了近年来欧洲国家新的粉尘卫生标准及其监测、管理方法,分析其制定粉尘卫生标准的经验,并与我国的粉尘卫生标准情况做了初步的比较,提出了建立我国新分级分类粉尘卫生标准体系的建议。     

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。     

CFD simulations of dust dispersion in the 20 L vessel: Effect of nominal dust concentration

Measurements of flammability and explosion parameters for dust/air mixtures require uniform dispersion of the dust cloud inside the test vessel. In a previous work, we showed that, in the standard 20 L sphere, the dust injection system does not allow generation of a uniform cloud, but rather high gradients of dust concentration are established. In this work, we used a previously validated three-dimensional CFD model to simulate the dust dispersion inside the 20 L sphere at different dust nominal concentrations (and fixed dust diameter). Results of numerical simulations have shown that, as the dust nominal concentration is increased, sedimentation prevails and, thus, when ignition is provided, the dust is mainly concentrated at the vessel walls.     

Current status and expected future trends in dust explosion research

In spite of extensive research and development for more than 100 years to prevent and mitigate dust explosions in the process industries, this hazard continues to threaten industries that manufacture, use and/or handle powders and dusts of combustible materials. Lack of methods for predicting real dust cloud structures and flame propagation processes has been a major obstacle to prediction of course and consequences of dust explosions in practice. However, work at developing comprehensive numerical simulation models for solving these problems is now on its way. This requires detailed experimental and theoretical studies of the physics and chemistry of dust cloud generation and combustion. The present paper discusses how this kind of work will promote the development of means for prevention and mitigation of dust explosions in practice. However, progress in other areas will also be discussed, e.g. ignition prevention. The importance of using inherently safe process design, building on knowledge in powder science and technology, and of systematic education/training of personnel, is also emphasized.     

武钢烧结厂401转运站除尘管道堵塞的原因分析

对武钢烧结厂401转运站除尘管道经常堵塞的原因进行了理论分析和计算,计算结果与工艺要求的有关参数进行对照,找出了现有除尘管道堵塞的原因,并提出了相关的改进措施.     

复合多管除尘器用于链条锅炉烟气除尘

针对链条锅炉烟气旋风除尘器改造,介绍惯性沉降—旋风复合型除尘器用于燃煤链条锅炉烟气除尘。     

Visualization and analysis of dispersion process of combustible dust in a transparent Siwek 20-L chamber

Dust explosion severities are closely associated with dust dispersion behaviors. To characterize the dispersion process of dust cloud, visualization experiments were conducted by using a transparent Siwek 20-L chamber. Dispersion processes of typical carbonaceous dust were recorded by a high-speed camera and, with the image processing technique, the qualitative analysis based on the transmission of dust cloud was carried out. Results have evidenced the three consecutive stages of dust dispersion process: the fast injection stage of dust particles, the stabilization stage and the sedimentation stage of dust cloud. The motion of dust particles and the variations of dust cloud in space and time can be clearly distinguished. In the stabilization stage, the good uniformity of dust dispersion is achieved when the deviation of transmission data at different locations reaches to the minimum value. Under different nominal dust concentrations, the time periods for dust dispersion stabilization are found to be significantly different, suggesting that different dust concentrations should correspond to different ignition delay in order to accurately measure the explosion characteristics in the Siwek 20-L chamber. Moreover, it is found that the decrease trend of transmission with increasing nominal dust concentration will become gradually leveling off, different from the inversely proportional relationship according to the Bouguer's law, and this indicates that the actual dust concentration will be lower than the nominal concentration or the dust cannot be fully dispersed at the case of high dust concentration. According to the experiment, when the nominal dust concentration exceeds to 1000 g/m³, the transmission will no longer vary visibly.     

Analysis of dust distribution in silo during axial filling using computational fluid dynamics: Assessment on dust explosion likelihood

In this study, the dust distribution in a silo during axial filling was modelled using a commercial computational fluid dynamics (CFD) code. The work focused on the dust concentration distribution in the silo, for evaluating the likelihood of a dust explosion in the silo. The simulation was conducted using a combination of renormalized (RNG) k-epsilon and discrete phase models, with standard pressure interpolation and a second order upwind scheme. The predicted dust concentration distribution showed a good agreement with experimental data adopted from the literature. It was found that the dust concentration distribution was influenced by mean velocity and turbulence flow. The simulation results suggest that the cornstarch concentration inside the silo was always above the lower explosion limit (LEL), hence requiring a mitigating action or a control system to reduce the explosion risk.