纤维束过滤技术处理微污染水源水的中试研究

采用纤维柬过滤技术与均质滤料过滤技术处理某石化水厂的微污染源水。结果表明,纤维柬过滤技术比均质滤料过滤技术对浊度、色度的去除效果更好。纤维柬过滤在滤速为15m／h时,出水浊度最低可达0．2NTU以下,色度为10倍,过滤周期为36h;在滤速为20m／h时,出水浊度仍能达到0．3NTU以下,且过滤周期可达到24h。均质滤料过滤在滤速为8m／h时,出水浊度最低只能达到0．3NTU,色度为15倍,过滤周期为24h。纤维柬过滤技术具有阻力小、滤速快的特点,对中小水厂改扩建有积极的推广价值。     

基于环境气溶胶的防护用口罩过滤性能研究

根据口罩阻挡环境气溶胶微粒吸人人体的使用要求,模拟人体呼吸阻力(通常为30～50 Pa).采集部分市场销售口罩和新型医用组合滤料口罩作为测试对象,对过滤环境气溶胶中0.3～0.4 μm粒径区间的颗粒物的性能进行测试.结果 表明:纱布口罩(8层)透气性大,但对环境气溶胶微细颗粒物的过滤效率低于10.0％,且3个纱布口罩叠用(24层)的过滤效率仍低于30.0％.活性炭口罩呼吸阻力适中,对环境气溶胶微粒的过滤效率为37.5％～44.6％.5#～7#无纺布口罩过滤效率在66.8％～80.4％,但呼吸阻力较高.新型医用9#口罩滤料过滤效率为80.5％～82.1％,空气流量为20.0～ 36.3 L/min,过滤性能最佳.新型医用组合滤料具有低阻高效特点,是一种环境气溶胶防护用口罩的理想过滤材料.     

常见袋式空气过滤器过滤特性测试研究

为更好地应用空气过滤器,保证其最佳的使用条件,通过用空气过滤器性能实验台测试一般通风用袋式空气过滤器,对其阻力、过滤效率特性进行相关研究.研究结果表明:对于实验中两中效纤维袋式过滤器,滤料结构本身差异可导致阻力从1 m/s风速下相差41.7 Pa增加到2.5m/s风速下相差111.8 Pa;在不同的截面风速下,0.3～0.5 μ m、0.5～1.0μm这两个粒径段颗粒物一次通过效率最大相差达9％,≥1.0 μ m粒径段颗粒物一次通过效率相差不明显,可根据袋式过滤器的最佳截面风速选择适宜的使用场所.     

覆膜滤料的性能测试研究

最近几年覆膜滤料以其优良的过滤性能引起了人们的关注。分析了覆膜滤料的过滤机理、过滤效率、过滤阻力、过滤风速等性能指标的研究现状，通过实验对针刺毡覆膜滤料和常规针刺毡滤料进行了性能比较，指出了覆膜滤料的主要优势在于它的表面过滤机理、除尘效率高、清灰彻底、压力损失稳定且保持较低水平、对滤袋的磨损小、适用的粉尘范围广、寿命长、能耗低、成本低等，供实际选用时作参考。最后，展望了覆膜滤料的发展及其应用前景。     

机械铸造用袋式除尘器滤料的性能试验研究

选取机械铸造用PTFE覆膜高硅氧滤料,未覆膜高硅氧滤料以及普通涤纶滤料进行实验研究,测试了三种滤料的力学特性,耐腐蚀特性以及过滤性能.结果表明:经PTFE覆膜的高硅氧滤料过滤效率远高于未覆膜的过滤效率,尤其是对于1.0μm以下粒径粉尘,覆膜的高硅氧滤料过滤效率比未覆膜的高出25％,且经PTFE覆膜后的高硅氧滤料在强酸强碱高温工作条件下都能长期稳定地进行过滤.     

新型驻电极空气过滤器容尘性能实验研究

新型驻电极空气过滤器的容尘性能实验结果显示,其初始阻力在1.0 m/s和2.5 m/s迎面风速下分别为14Pa和60 Pa,且阻力容尘后基本不变,初始PM2.5过滤效率分别为99.8%和97.6%。容尘过程中效率衰减缓慢,使用一段时间后PM2.5过滤效率仍在90%以上和50%以上,清洗后效率有较大提升。无明显臭氧产生,针尖放电高压稳定,功率较小仅为15W。     

同级粗效滤料的过滤性能测试研究

通过对同级的粗效滤料进行大气粉尘的过滤性能实验研究。结果显示,同一级别滤料在过滤效率和阻力存在着明显的差异,在滤速1.2 m/s时,滤料效率达到最大。同级别中的G3样品1和G4样品3具有较高的效率,主要差异原因是滤料的纤维直径和孔隙率,可为过滤器粗效滤料的选择提供参考价值。     

浅析袋式除尘器孔隙率与过滤特性之间的关系

本文阐明了对袋式除尘器用滤料进行表面技术处理的必要性及其产生的相关问题,并通过现有理论及实验研究结果对滤料孔隙率与过滤阻力、过滤效率之间的两组关系分别进行分析论证,得出两组关系在除尘实践中存在的矛盾:滤料的孔隙率增大,过滤阻力减小,但是过滤效率也随之减小;而当孔隙率减小时,过滤效率增大,过滤阻力也增大。在实际过滤除尘工程中,用户和设计者往往希望拥有高效低阻的过滤材料。为此本文给出了解决这个矛盾的思路,以及依据实际过滤除尘工况寻找复合滤料最佳孔隙率的具体操作方法,这不仅对滤料的性能优化设计、选择提供了方法指导,还将有助于新型滤料的研发,同时也避免了对滤料进行表面处理时存在的盲目性。     

HBT"梯度"复合滤料的过滤性能研究及应用

针对常用滤料阻力过高的情况,本文将介绍一种新型的复合滤料-HBT"梯度"复合滤料。首先分析了其特殊的"梯次"结构和表层过滤机理,并借助实验的手段测试了其在冷态条件下的过滤效率、过滤阻力等过滤性能指标,测试结果显示HBT"梯度"复合滤料具有"低阻、高效"的特性,最后介绍了其在某电厂实际工程中的应用情况,并给出了实际的运行测试数据,应用的结果也证明了其具有较好的过滤性能和物化性能。     

颗粒物尺度对滤料过滤性能的影响

介绍了不同学者对滤料过滤机理的研究结果,实验研究了颗粒物尺度对粗、中、高效滤料过滤效率和过滤阻力的影响,对合理选择空调系统过滤材料提出了建议。     

高风速下线板式静电集尘器提效试验研究

为解决室内线板式静电集尘器在高风速条件下效率偏低的问题,设计制作了双区分体式静电集尘器样机,并通过测试该样机在不同条件下的PM2.5一次性过滤效率,考察了影响线板式静电集尘器高风速下性能的关键因素。结果表明,增加电离区"有效电流",减小集尘区极片间距,增加集尘区厚度是提高线板式静电集尘器高风速下性能的有效手段。依据试验结果对现有集尘器产品的电离区与集尘区进行优化改进并测试其在不同风速下的PM2.5一次性过滤效率表现。优化后的集尘器整体效率提升明显。     

Estimating the frequency distributions of PM10 and PM2.5 by the statistics of wind speed at Sha-Lu,Taiwan

The frequency distribution of air pollutant concentration varies with the meteorological conditions and pollutant emission level. There exists a simple relation between the frequency distribution of wind speed and frequency distribution of air pollutant concentration. The concentration of air pollutant, C, at cumulative probability, p, is inversely proportional to the wind speeds, u, at probability of (100 - p) when the distributional types and shape factors of both data are the same. The relationship is shown as K=Cp u(100 - p), where K is constant. In this study, three theoretical distributions (log-normal, Weibull and type V Pearson distributions) are selected to fit the measured data of PM10, PM2.5 and wind speed. The frequency distributions of air pollutants can be estimated from the simple relationship of air pollutant concentration and wind speed. The results show that the log-normal distribution is the best one to represent the data of PM10, PM2.5 and wind speed. The K values of PM10 and PM2.5 are nearly constant from the 30-80th percentiles. It was also found that the distributions of PM10 and PM2.5 can be successfully estimated from the distribution of wind speed. The Kolmogorov-Smirnov (K-S) test shows that there is no significant discrepancy between the estimated and measured distribution of PM10 and PM2.5 at the 95% confidence level. Therefore, the distribution of air pollutants is easily estimated when the wind speed data are known.     

两种消防水带的干燥特性及干燥模型研究

为加强消防水带的维护保养,设计了一款基于空气源热泵的闭式干燥装置,以达到低能耗、快速干燥的目的。通过实验的方法探究送风温度、速度对衬里为橡塑和聚氨酯两种材质消防水带的干燥特性的影响,并利用Wang and Singh干燥模型拟合建立了两种材质消防水带的干燥模型。送风温度由30 ℃每提升10 ℃,衬里为橡塑的消防水带干燥时间分别减少23.1%、30.2%,衬里为聚氨酯的消防水带分别减少25.1%、43.4%。相较于风速为2 m/s的工况下,风速为3 m/s时两种材质消防水带干燥时间减少不明显,风速为4 m/s时分别减少9.3%和30%。送风速度为3 m/s,30,40,50 ℃下衬里为聚氨酯的消防水带干燥时间比衬里为橡塑的消防水带分别减少26.4%、68.8%、67.2%;送风温度为50 ℃,送风速度为2,3,4 m/s时,衬里为聚氨酯的消防水带的干燥时间比衬里为橡塑的消防水带干燥时间分别减少34.8%、40.1%、49.8%。     

地铁公共区正压送风临界风速分析

对地铁站台站厅公共区楼扶梯口正压送风挡烟临界风速进行了理论分析和数值模拟研究。结果表明,公共区正压送风挡烟临界风速会受到地铁站的空间结构及火灾多样化等诸多因素的影响;规范要求的公共区楼扶梯口1.5m/s的正压送风挡烟风速只能阻挡站台2.8MW火灾烟气不向站厅蔓延。考虑最不利情况,建议地铁站台站厅公共区楼扶梯口正压送风挡烟风速不应小于1.8m/s。     

2,3,7,8-TCDD equivalence and mutagenic activity associated with PM10 from three urban locations in New Zealand

Ambient particulate matter (PM(10)) in urban centres varies depending on emission sources, geography, demography, and meteorology. Hence physical (PM(10), wind speed, rainfall, temperature), chemical (polycyclic aromatic hydrocarbons, PAH), and toxicological (Ames Test, H4IIE EROD Assay) analyses were done on daily PM(10) (approximately 1640 m(3)/day) collected from three New Zealand urban sites where winter emissions were predominantly due to domestic home heating. Daily PM(10) levels ranged between 9.7 and 20.8 in summer and between 21.8 and 61.0 microg/m(3) in winter. Daily PAH concentrations were 0.5, 0.45, and 1.5 ng/m(3) in summer and 52.1, 128.9, and 5.8 ng/m(3) in winter at sites Christchurch, Alexandra and Dunedin, respectively. During winter, 74% of PM(10) extracts from all three sites showed significant mutagenicity in the Ames Test (TA 98, -S9), whereas approximately 25% of the daily PM(10) was mutagenic in summer. Benzo[a]pyrene and BaP carcinogenic equivalence concentrations during winter were strongly correlated to both mutagenicity and TCDD-like activity at two sites. Daily levels of TCDD toxicity equivalence concentrations ranged from 0.5 to 3.6 pg TCDD/m(3) air in summer and from 0.3 to 4009 pg TCDD/m(3) air in winter. Chemically and biologically derived TCDD toxicity equivalent concentrations were significantly correlated in all study locations indicating that PAH may represent most of the TCDD-like activity present in the PM(10).     

空调工况下空气柱送风仿真模拟与舒适度评价

本文对空调工况下空气柱(上送下回)送风的气流组织,温度场,速度场,空气龄进行了仿真模拟。结果表明。制冷工况下,送风温度为18℃、20℃,风速为3 m/s、空气柱高度为2~2.5 m时,单柱舒适区大小为21 m×21 m×1.7 m,区域ADPI值均大于80%,平均PMV值为-0.34,平均PDD值为8.67%。制热工况下(上送下回),送风温度为26℃、28℃、30℃,风速为2~4 m/s、空气柱高度为2~2.5 m时,区域ADPI值均大于90%,平均PMV值为-0.47,平均PDD为10.2%。单柱区域内制冷工况热舒适性优于制热工况舒适性。     

基于风热环境的开敞空间周边建筑围合研究

城市形态与环境舒适性的关系是城市设计的热门议题。探讨风热环境参数与街区围合度的关系及开敞空间周边建筑的围合形式，目的在于为空间形态控制提供思考路径。选取武汉市的开敞空间共68处作为研究对象，在此基础上抽象出具有代表性的街区理想空间模型，运用Phoenics软件量化模拟冬夏两季典型日的典型时刻不同围合度下室外环境空气速度、温度和空气压力值，并进行相关性分析。结果显示，城市集中建设区开敞空间周边建筑围合度与夏季空气速度呈负相关关系。最后根据风环境对人体影响的分析结果对开敞空间提出相应的城市设计建议。     

Comparison and further development of parametric tropical cyclone models for storm surge modelling

Cyclone forced storm surges cause severe damage to coastal structures and loss of human lives and properties. In cyclone protection and warning it is important to be able to calculate the cyclone air pressure and wind field on the basis of rather limited information, such as cyclone position, pressure drop, maximum wind speed and radius to maximum wind speed. In the present work, parametric cyclone models based on such limited information are investigated and compared. Analytical expressions of the tangential and radial velocity distributions are derived from the governing momentum equations. It is found that the analytical models provide very similar air pressure and tangential wind speed distributions. Instead of using a simple formulation of the deflection angle, the derived analytical expression of the radial velocity distribution is used and compared to earlier numerical solutions. A procedure is formulated for estimation of the shape of the cyclone on the basis of maximum wind speed versus pressure drop relations. Finally, examples of comparisons of measured and calculated air pressures and wind speeds and directions are presented.     

某住宅室外风环境模拟研究

选择新疆石河子地区某拟建住宅组团,在规划设计阶段初步方案确定后,进行室外风环境模拟,判断是否达到绿色建筑对室外风环境舒适度指标要求。结果表明,冬季工况下,住区主要干道及活动区域风速、室外风压、全区域最大风压差等均满足要求。夏季工况下,在室外主要活动区域出现局部无风区及涡旋区,不满足要求。通过调改拟建方案中建筑朝向后,模拟结果满足要求,住区室外风速为0~7.44m/s,平均风速为3.23m/s,住区风速在平均风速以上的区域占40%,住区室外主要活动区域未出现无风区和涡旋区。     

Particulate matter and carbon monoxide multiple regression models using environmental characteristics in a high diesel-use area of Baguio City, Philippines

In Baguio City, Philippines, a mountainous city of 252,386 people where 61% of motor vehicles use diesel fuel, ambient particulate matter <2.5 microm (PM(2.5)) and <10 microm (PM(10)) in aerodynamic diameter and carbon monoxide (CO) were measured at 30 street-level locations for 15 min apiece during the early morning (4:50-6:30 am), morning rush hour (6:30-9:10 am) and afternoon rush hour (3:40-5:40 pm) in December 2004. Environmental observations (e.g. traffic-related variables, building/roadway designs, wind speed and direction, etc.) at each location were noted during each monitoring event. Multiple regression models were formulated to determine which pollution sources and environmental factors significantly affect ground-level PM(2.5), PM(10) and CO concentrations. The models showed statistically significant relationships between traffic and early morning particulate air pollution [(PM(2.5)p=0.021) and PM(10) (p=0.048)], traffic and morning rush hour CO (p=0.048), traffic and afternoon rush hour CO (p=0.034) and wind and early morning CO (p=0.044). The mean early morning, street-level PM(2.5) (110+/-8 microg/m3; mean+/-1 standard error) was not significantly different (p-value>0.05) from either rush hour PM(2.5) concentration (morning=98+/-7 microg/m3; afternoon=107+/-5 microg/m3) due to nocturnal inversions in spite of a 100% increase in automotive density during rush hours. Early morning street-level CO (3.0+/-1.7 ppm) differed from morning rush hour (4.1+/-2.3 ppm) (p=0.039) and afternoon rush hour (4.5+/-2.2 ppm) (p=0.007). Additionally, PM(2.5), PM(10), CO, nitrogen dioxide (NO2) and select volatile organic compounds were continuously measured at a downtown, third-story monitoring station along a busy roadway for 11 days. Twenty-four-hour average ambient concentrations were: PM(2.5)=72.9+/-21 microg/m3; CO=2.61+/-0.6 ppm; NO2=27.7+/-1.6 ppb; benzene=8.4+/-1.4 microg/m3; ethylbenzene=4.6+/-2.0 microg/m3; p-xylene=4.4+/-1.9 microg/m3; m-xylene=10.2+/-4.4 microg/m3; o-xylene=7.5+/-3.2 microg/m3. The multiple regression models suggest that traffic and wind in Baguio City, Philippines significantly affect street-level pollution concentrations. Ambient PM(2.5) levels measured are above USEPA daily (65 microg/m3) and Filipino/USEPA annual standards (15 microg/m3) with concentrations of a magnitude rarely seen in most countries except in areas where local topography plays a significant role in air pollution entrapment. The elevated pollution concentrations present and the diesel-rich nature of motor vehicle emissions are important pertaining to human exposure and health information and as such warrant public health concern.