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51.
烟气脱硫喷淋塔气体旋流实验研究   总被引:10,自引:0,他引:10  
提出在烟气脱硫喷淋塔烟气进口设置导流板或采用切向进口,使烟气在塔内螺旋流动,以延长停留时间,加强气液湍动接触,并可改善系统的负荷调节适应能力。对不同进口结构的塔内流速分布、压力损失进行了实验研究,得出了旋流强度、压力损失等随导流板角度的变化关系,并将旋流情况与常规的直流进行了比较。  相似文献   
52.
在内径200mm,高度1100mm的喷淋塔内,采用Na2CO3作为吸收剂进行SO2吸收实验,重点研究了液气比(L/G)、空塔气速、进口SO2质量浓度、吸收液pH及初始浓度对脱硫效率的影响。通过实验得到该系统适宜操作条件:吸收液pH值在6.5~7.5之间,液气比在1~1.5之间,吸收液初始浓度5%,空塔气速1.6m/s,在此条件下,进口SO2质量浓度在3000mg/m3以内,脱硫效率可以达到80%以上。  相似文献   
53.
针对内蒙古自治区火力发电厂烟气脱硫装置运行现状,结合内蒙古环保厅工况在线平台和总量核算需求,以双膜理论为基础模拟脱硫喷淋塔内部的化学反应及相际传质过程,建立一个包含所有含硫组分浓度及传质速率的数学模型。得到的常系数微分方程用Runge-Kutta法求解。为适应环境监管平台的需要,对模型进行优化,得到一个脱硫效率模型。将模型预测结果与在线监测数据进行比较,误差分析表明模型具有较高的预测能力,且对不同的机组具有通用性。  相似文献   
54.
大型原油储罐热喷涂防腐蚀技术的应用   总被引:2,自引:2,他引:2  
金属热喷涂技术是一种有效的长效防腐蚀手段,常用于金属结构的腐蚀防护。从钢结构腐蚀及热喷涂长效防护的角度,阐述了在大型原油储罐建设中使用热喷涂防腐蚀技术的可行性和经济性,并对其热喷涂防腐蚀工艺作了简要说明。  相似文献   
55.
用X-射线衍射分析技术和化学方法研究不同农业利用方式对湘南第四纪红粘土及其发育土壤的粘粒矿物学组成和表面电荷特性的影响.结果表明:湘南第四纪红壤的粘粒矿物组成以高岭石为主,其次是1.4nm过渡矿物.经过人为耕种尤其在水田条件下,蛭石和水云母的含量增加,铁的活化度增大.土壤表面电荷数量(CECpH3.2、CECp、CECv、AEC)和电荷零点(pH)的值也发生相应的改变.  相似文献   
56.
It is important to study the characteristics of the nozzle of the deluge spray to comply with the standards developed by the petroleum industry for offshore installations in Norway. Due to the stochastic nature of the decomposition processes and geometrical features within the nozzle, the deluge spray has a complex flow field. Since the flow field determines the performance of the spray, the present study performs an experimental characterization of a medium velocity deluge nozzle for validation of computational fluid dynamics (CFD) models. The experiment was conducted for a maximum supply water pressure of 8.0 bar (g), which is identical to the operating pressures of offshore installations. Formerly, characterization studies of deluge or sprinkler spray were mostly targeted on residential usage with lower supply water pressures. I utilized a laser-based shadow imaging system to capture high-speed images, which were later processed in MATLAB. A linear patternator was used to validate the results of the shadow imaging technique. The geometrical features of the deluge nozzle played an important role in determining the characteristics of the spray. In addition, the supply water pressure significantly affected the size and velocity distributions of the droplets, applied density (volume flux), and area coverage. However, the Sauter mean diameter did not vary significantly with the azimuthal or radial position of the droplet within the inner region of the spray. The measurements obtained in this study can be used to estimate the extinguishing efficiency of a deluge system for offshore installations with elevated supply water pressures. Deviations between measurements with shadow imaging and patternator technique are discussed and discrepancies are discussed.  相似文献   
57.
喷雾干燥法在垃圾焚烧尾气净化中的应用   总被引:1,自引:0,他引:1  
以枣庄市资源电厂为例,介绍了喷雾干燥法在垃圾焚烧尾气净化中的应用。  相似文献   
58.
It is often difficult to measure and predict the impacts of toxic chemicals, such as herbicides, on natural communities. This is especially true under conditions of spray drift when the amount received by the organisms downwind from the sprayer may be at sub-lethal doses. Laboratory experiments are either artificial, or have not been generally carried out over long enough time periods, to be realistic. Field experiments are often difficult because of the high variability inherent in natural populations. Here an intermediate microcosm approach was used, where standardized artificial communities (eight dicotyledons with and without a grass) were tested. The artifical communities included species typical of British woodland margins, hedgerows and field margins; communities with a high conservation interest, yet potentially under threat from spray drift. The microcosms were placed downwind of a sprayer and exposed to one of the following herbicides: glyphosate, mecoprop and MCPA. This approach ensures that the communities were standardized at the start and have been exposed to realistic doses of herbicide. The experiments reported here were carried out for at least three years with exposures to herbicides repeated each year. The effects of differential herbicide exposure downwind of the sprayer were measured on species yield, flowering performance, seed production, seed viability and invasion by new species. Responses were extremely variable, but all species showed some effects in some years. Some patterns emerged. For example, one group of species appeared to be more successful near to the sprayer. This was particularly true of the grass when exposed to MCPA and mecoprop. The performance of most species was reduced under the sprayer, and there was a general recovery with increasing distance downwind. A few species showed increased performance in the intermediate downwind zone (2–4 m) and this may be due to a hormonal effect on growth processes, or an effect of reduced interference from other community members. Generally, there were few effects on seed production or seed viability. An important result was that most effects were confined within an 8 m zone, as there were few significant differences between plants exposed at 8 m and those untreated. Although damaging effects were found in the immediate downwind zone from the sprayer, the restriction of effects to 8 m suggests that a buffer zone of this size would be adequate to protect sensitive habitats from most deleterious impacts on community processes.  相似文献   
59.
水泥生产过程中燃煤产生的二氧化硫是当今主要的大气污染物 ,对水泥厂排放的废气进行治理是环境保护的重要课题之一。本文介绍了对水泥厂烟气进行低温脱硫的研究成果 ,阐述了喷雾干燥技术用于水泥厂废气脱硫的原理、设计方法  相似文献   
60.
叙述了磺化法生产苯酚碱熔工段碱雾污染治理的技术措施 ,指出在原碱雾回收流程中的旋风分离器上部设置喷淋吸收装置 ,并采用 5 %~ 10 %的氢氧化钠碱液吸收碱雾 ,可取得明显的治理效果  相似文献   
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