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71.
研究了以锅炉烟气沉降物为吸附剂的烟炱吸附法脱除SO2的工艺条件,结果表明该法较适宜的工艺条件为SO2浓度小于2400mg/L,烟气流速小于36m/h,烟气温度低于100℃,此时脱硫效率可达30%以上。初步探讨了烟炱吸附法脱硫的作用机理。  相似文献   
72.
考虑到大型构件喷砂(涂)车间铝粉尘污染的特点以及构件进出空间的限制,比较了各种类型的除尘器,选择了最合理的通风除尘方案,进行了通风除尘系统的设计。该设计方案实施后,除尘效果显著。  相似文献   
73.
介绍了烟草粉尘爆炸特性,对我国烟草加工系统粉尘爆炸危险性作了分析。  相似文献   
74.
六号高炉炉前出铁场工程是一项工业污染治理项目,该项目结合安钢实际,利用较少的投资,解决了多年困扰炼铁厂的炉前烟尘污染的问题,该技术结合目前国内中小高炉出铁场综合治理的经验,提出了顶吸加侧吸的综合捕集方式,极大地改善了出铁场的烟尘污染状况,同时回收的粉尘又有极高的利用价值,取得了一定的经济效益。  相似文献   
75.
By using observational data and MM5, an observational analysisand numerical study was conducted on the synoptic condition of a severe dust storm that was caused by a Mongolian cyclone whichoccurred from 6 to 8 April 2001. Results illustrated thatthe cyclogenesis was due to the isentropic potential vorticity (IPV) advection in the upper troposphere and the terrain modifiedbaroclinicity in the mid-lower troposphere. The Altai-Sayan complex of mountains blocked the lower level cold air and made the isentropic surface sharply steep. When the air slid down along the isentropic surface the increasing of baroclinicity anddecreasing of stability blew up the vertical vorticity development.The formation of the dust storm was a result of a cyclonic cold front passing across the area. The occurrence of this dust stormwas closely related to the strong surface wind, which was accompanied by a cold front passing, rather than the cyclogenesis, itself. Hence, the reason for the pre-front dust storm formulation was the formation of heating convection. Reasons behind the formation of a black storm (visibilitylower than 50 m), which occurred in the mid-north part ofInner Mongolia, lay in several aspects. Firstly, in thisarea the surface wind was strong, a direct result of thedownward transport in mid-lower troposphere. Secondly,the cold front passed over the effected area near sunsetso the air obtained much more surface heating to form adeeper mixed layer (ML). Thirdly, cooperation between thelower level wind and the terrain made the atmosphere inthis area and acquired the maximum advective contributionnecessary to form a deep post-front ML. The sensitivityexperiment revealed that surface heat flux was important to the frontal lifting. In addition, the forcing of surface heating wasalso seen as the primary forcing mechanism of frontogenesis. Meanwhile, removal of the surface heat flux made the atmosphericstratification became stable and the pre-storm ML very shallow,which weakened the strength of the dust storm.  相似文献   
76.
ABSTRACT: Ground water contamination by excess nitrate leaching in row‐crop fields is an important issue in intensive agricultural areas of the United States and abroad. Giant cane and forest riparian buffer zones were monitored to determine each cover type's ability to reduce ground water nitrate concentrations. Ground water was sampled at varying distances from the field edge to determine an effective width for maximum nitrate attenuation. Ground water samples were analyzed for nitrate concentrations as well as chloride concentrations, which were used as a conservative ion to assess dilution or concentration effects within the riparian zone. Significant nitrate reductions occurred in both the cane and the forest riparian buffer zones within the first 3.3 m, a relatively narrow width. In this first 3.3 m, the cane and forest buffer reduced ground water nitrate levels by 90 percent and 61 percent, respectively. Approximately 40 percent of the observed 99 percent nitrate reduction over the 10 m cane buffer could be attributed to dilution by upwelling ground water. Neither ground water dilution nor concentration was observed in the forest buffer. The ground water nitrate attenuation capabilities of the cane and forest riparian zones were not statistically different. During the spring, both plant assimilation and denitrification were probably important nitrate loss mechanisms, while in the summer nitrate was more likely lost via denitrification since the water table dropped below the rooting zone.  相似文献   
77.
矿山呼吸性粉尘危害程度评价法研究侯祺棕(武汉工业大学资源与环境工程系)[摘要]通过对矿山呼吸性粉尘实际危害程度评价法的研究,并经实例检验,推荐两种具有可操作性和足够准确的评价法,这对矿山呼吸性粉尘监测新技术的推广具有重要意义。[关键词]呼吸性粉尘,危...  相似文献   
78.
煤炭筛分系统在工作时产生的大量煤尘对环境造成污染,为解决这一问题,我们设计安装了两套煤炭筛分除尘系统,通过布袋式除尘器,把煤尘用布袋收集起来,解决了煤炭粉尘污染问题,通过三年的使用观察,效果非常明显。  相似文献   
79.
综合分析了除尘系统进入的烟尘量、排放方式、排放浓度等5个参数及其相互关系,根据在一定时间内进入除尘系统烟气烟尘的量;对除尘器进口和出口即百叶窗内各方向烟尘浓度的测试,利用物料平衡方程,确定百叶窗内各测点各方向测定的烟气烟尘浓度,确定半敞开排放烟气烟尘的排放浓度,笔者发现,外排烟尘浓度与百叶窗内侧向烟尘浓度具有良好的线性关系,百叶窗内侧向测定烟尘浓度能够反映半敞开烟气排放浓度。据此,提出以半敞开方式排放烟气烟尘的除尘系统烟气烟尘浓度测试方法,即侧向间接测试法。  相似文献   
80.
抽出式通风煤巷掘进过程中粉尘浓度分布规律的数值模拟   总被引:4,自引:0,他引:4  
根据气固两相流理论,针对矿井掘进工作面的特点,采用计算流体力学的离散相模型(DPM)对掘进工作面通风过程中粉尘浓度进行数值模拟,总结抽出式通风掘进巷道中粉尘浓度的沿程分布及变化规律。  相似文献   
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