不同排尘结构对导叶式旋风管内气固两相流动影响的数值研究

通过数值模拟的方法对3种不同排尘结构的导叶式旋风管内气固两相流场进行了研究。结果表明,直筒型排尘结构的排尘口处上、下行流交错容易产生返混夹带现象,对细颗粒的分离不利;锥形排尘结构可以增加旋风管内气流旋转强度,控制进入灰斗的下行气量,有利于分离效率的提高,但排尘锥内部存在环形旋涡,易磨损器壁;在排尘锥侧面开缝,可改善旋风管内流动分布状态,实现排尘区气固两相分流,进入灰斗内的气流更加稳定,从而有效减少颗粒返混夹带,提高旋风管分离性能。     

同轴矿渣熄灭火器的应用与改进

同轴矿渣熄灭火器的应用与改进我厂硫酸生产中的渣尘采用干法冷却连续排渣，由沸腾炉、气体冷却除尘器、旋风除尘器排出的高温渣尘，经由一台６３０ｍｍ×１８０００ｍｍ的内螺旋滚筒冷却器至增湿器，而后以手推车送至渣场。由于渣尘经过滚筒冷却后，温度仍然较高，一般都...     

一种沸腾炉除尘脱硫及尘灰处理方法

<正>一种沸腾炉除尘脱硫及尘灰处理方法,包括:沸腾炉、降尘室、排气管、沸腾炉底灰斗、沸腾炉排烟口、降尘斗、尘风管、旋风除尘器、除尘器排风口、排风管、双联旋风除尘器、旋风除尘器出风管、水浴脱硫塔、脱硫塔进风管、排风口、引风机、烟囱、沉淀水池、水泵、水泵出水管、喷水管、水泵自吸真空器、滤网罩、清水池、清水池溢水管、双联继动阀、排尘泥口、湿灰水池、湿灰;其特征是:沸     

排尘锥开缝结构对导叶式旋风管内细颗粒分离性能的影响

在导叶式旋风管下端安装排尘锥,通过改变排尘锥的开缝结构来改变含尘气固两相流的流动状态,从而实现旋风管的减阻增效.通过对比分析排尘锥开缝结构的变化对旋风管的压降、分离效率及粒级效率的影响.得到排尘锥开缝有助于提高7μm以下细颗粒的分离效率.     

排尘锥结构对旋风分离器内气固两相分离性能影响的研究

通过数值模拟的方法,采用RSM湍流模型对直切式旋风分离器三种不同排尘锥结构(排尘锥无缝、开对称缝、开阶梯缝)下的气固两相流场进行了研究。研究表明,三种排尘锥结构都可以将粒径大于8μm的返混颗粒再次分离下来;排尘锥开缝起到分流作用,有效改善排尘锥内气相流场分布,降低压降,便于返混颗粒从侧缝排出,提高抗返混能力,减少颗粒在排尘锥内部长时间停滞的机率,减小堵塞下口的可能性;排尘锥开阶梯缝可以减小涡核中心不对称性,明显提高侧缝的排尘能力,有效消弱返混夹带对3μm小颗粒的影响,提高分离器的操作弹性,减少颗粒间的磨损,为排尘锥结构的进一步优化、提高旋风管分离性能提供依据。     

提高伞型炉篦破渣排渣能力

化肥生产中,要求造气炉篦具有较大的通风面积,较强的破渣和排渣能力。因而各种新型炉篦相继出现。伞型炉篦是目前使用较多的一种。我厂在使用伞型炉篦过程中发现它的破渣、排渣能力还不够强,结疤、挂炉现象时有发生,1983年两台炉每隔2～3     

排尘结构对导叶式旋风管内流动分布影响的数值研究

通过数值模拟的方法研究了排尘结构对装有分流型芯管导向叶片式旋风管内流场的影响规律。研究发现,随排尘口直径增加,环形空间切向速度增加,分离空间内旋流区切向速度增加,外旋流区切向速度减小,经分流型芯管侧缝流量减小;旋风管压降随排尘口直径增加而减小,排尘口直径为200mm和250mm时,旋风管能耗最低;锥体尺寸增加可有效减小灰斗区及外旋流区的能耗。     

利用钢厂炉尘制取磁性材料工艺探讨

本文论述了以钢厂炉尘为原料，制取磁性材料的方法。即解决炉尘对环境的污染问题，又为综合利用，变废为宝开辟了新的途径。     

膜喷射塔盘在炉气洗涤塔中的应用

<正>煅烧过程产生的炉气进入旋风分离器将碱尘分离后,炉气进入洗涤箱用冷凝液喷淋洗涤,再由顶部进入冷凝塔,降温后的炉气由洗涤塔下部进入与自上而下的软水相遇,再次洗涤除去残存的碱尘和氨,然后由风机抽出放空,洗涤液送至过滤系统用作洗涤水。1现状及存在问题(1)Φ2 500 mm煅烧炉炉气洗涤塔原来为Φ1 600 mm填料塔,因为填料塔阻力相对较大,风机克服系统阻力后不能满足浓气低压机进口微正压的要求,不经回收而全部放空;而且由于洗涤     

高浓度含尘炉气中粉尘和湿含量测定方法

一、前言一般含尘风道测尘技术,在目前不存在什么技术关键问题,並有较成熟的测定方法可应用。但对高浓度含尘的风道测尘技术,目前还没有一个较稳定的方法可应用。如沸腾炉、旋风炉、干法回转窑,出口烟气含尘浓度一般均高达100克/标米~3以上。同时有些矿尘的物理     

喷雾干燥烟气脱硫技术在玻璃熔窑上的应用

喷雾干燥烟气脱硫工艺发明于上世纪70年代,玻璃窑厂排放的烟气中含有大量的酸性气体,严重危害自然环境和人类健康。根据玻璃熔窑的烟气特点和我国的国情,对传统的工艺进行改进,现已把喷雾干燥烟气脱硫工艺成功应用于玻璃熔窑上。排放烟气中SO2含量200mg/m3,脱硫效率达到90%以上,同时,排放烟尘含量40mg/m3,除尘效率达到99%。     

喷砂及粉尘污染的综合治理

针对基体前处理技术中的喷砂存在的两大问题:1)砂料不能循环利用,工艺成本高,资源浪费严重;2)粉尘控制方法单一,除尘效果不良,环境污染严重,影响人体健康。按照未来经济发展乃至先进制造技术及表面处理技术的总趋势和高效率、低能耗、低污染的要求,研制了真空循环喷砂工艺和二级除尘综合治理方案,实现了节约成本、保护环境和人体健康的目的。     

A method for estimating the dust yield of powders

A method is described by which powders may be compared with respect to their potential to liberate airborne dust during certain manufacturing processes. Thus it is possible to select quickly from a range of otherwise suitable powders the powder with the lowest dust yield, which reduces the precautions required to prevent exposure of factory personnel to the dust.A weighed quantity of the powder is poured through a standard height in a cabinet. Airborne dust, irrespective of particle size (“total” dust), is collected on a weighed filter in an open filter holder and, in a separate test, after passage through a horizontal elutriator which separates respirable dust capable of penetrating to and being deposited in the human lung. The weights of respirable and “total” dust are expressed in relation to the weight of powder tested.     

磷肥生产中生产性粉尘、噪声的危害及预防

本文分析了磷肥生产过程中产生的粉尘及噪声对人体的危害以及采取的预防措施。     

陶瓷之路与江南旅游都市

景德镇是陶瓷之路的重要源头,世界陶瓷文化遗产密集区,具有国际垄断性。要建设成融历史文化与现代文明为一体的江南旅游都市,必须要政策创新、体制创新、机制创新,充分发挥世界品牌效益,争取国际援助,招商引资。开发人力资源、拓展客源市场、兴建海上陶瓷之路遗产廊道,以陶瓷为灵魂、人文为背景、生态为依托,让人类分享世界文明。     

Atmospheric Aging of Asian Dust Particles During Long Range Transport

Variations of mixing state and chemical constituents of Asian dust (AD) particles having different transport pathways were investigated by measuring hygroscopicity and volatility of size-selected (1 μm) dust particles, and their morphology and elemental composition in Gwangju, Korea. Also, hygroscopicity and volatility of possible candidate chemical species that can be included in the dust particles was measured in a laboratory for comparison with field data. A significant amount of dust particles were found to be aged by internally mixing with hygroscopic and volatile species in different ways, depending on their transport pathway. Formation of hygroscopic CaCl₂ and/or cloud processing of dust particles with sea-salt species were proposed as being central to the formation of hygroscopic species in the “less polluted AD” (in which the air mass arrived at sampling site without passing over significant industrial areas), and the existence of hygroscopic species in the “highly polluted AD” (in which the air mass passed over major industrial areas) was explained by the interaction of dust particles with anthropogenic pollutants (i.e., Ca(NO₃)₂ formation by heterogeneous reaction of HNO₃ with dust particles and condensation of hygroscopic H₂SO₄ or (NH₄)₂SO₄ onto the dust particles). Volatile carbonaceous species, which would exist on the surface of the dust particles, were also observed and their fraction significantly increased in the highly polluted AD due to a higher possibility to encounter air masses containing a significant amount of carbonaceous species. Morphological and elemental data identified three types of aged dust particles (reacted dust, cloud-processed dust, and aggregated dust). The production of various aged dust particles depending on their transport pathways has important implications on their different effects on cloud formation, radiation balance, and human health from original dust particles.

Copyright 2012 American Association for Aerosol Research     

通风除尘系统中吸尘罩的设计与计算

吸尘罩是通风除尘系统中的重要部件,通过分析吸气口的气流运动规律,提出了吸尘罩的设计计算方法以及所遵循的设计原则,为准确地进行通风除尘系统的设计提供了依据.     

石灰出库自动除尘系统的改进

石灰在出库过程中,通过光电开关感应使通风除尘电机自动变频启动,含尘气体在引风机负压的作用下被布袋统一收集,收集后的灰粉进入集灰斗,通过螺旋输送机排入提升机,实现了除尘系统的自动变频启动和灰粉的回收、利用,降低了烟尘的排放浓度。     

The effect of polydispersity on dust lifting behind shock waves

Knowledge-based modeling of dust lifting behind shock waves is a prerequisite for realistic simulation of dust explosions. Mostly numerical simulations of this process focus on dusts consisting of monodisperse particles, while real dusts are polydisperse. This article investigates the effect on the lifting process of the dust being polydisperse with a log–normal distribution of particle sizes. The spatial distribution of the various sizes in the rising layer is studied, and statistical results for the rise, the collision frequency and the particle kinetic energy are compared for polydisperse and monodisperse dusts. It is shown that a layer consisting of polydisperse particles rises significantly faster than a one consisting of monodisperse particles, all other parameters being the same.     

烧结厂转运点高浓度粉尘的吸尘罩捕收规律

通过对烧结厂皮带机转运点扬尘理化特性、吸尘罩内粉尘流、抽风参数与所捕收粉尘粒度与质量变化规律等的研究,探讨了吸尘罩对高浓度粉尘的捕收规律. 结果表明,该处扬尘浓度大于3000 mg/m3,真密度为4.040 g/cm3,球形度为0.51~0.93,TFe和CaO的总含量高达62%~64%(w). 随抽气速度增大,吸尘罩内粉尘浓度逐渐升高,抽吸气流的捕尘作用逐渐取代诱导气流的扬尘作用,当抽气量增加到一定值后,抽吸气流开始激发附着在料床上静止的粉尘. 随抽气速度增大,吸尘罩所捕收粉尘的总质量和最大粒度不断增大,呼吸性粉尘量大幅降低. 为避免大量激发料床上静止的粉尘,吸尘罩的经济抽风速度应不高于9.20 m/s,捕收的粉尘颗粒小于112.62 mm的占97%.