纳米光催化活性炭纤维净化空气初探

本文重点介绍了纳米光催化原理、特点及纳米光催化或活性炭纤维单独净化空气时的优缺点，分析了将纳米光催化和活性炭纤维相结合的方式及优点。充分利用了纳米光催化技术和活性炭纤维的优点，达到了净化空气的目的。并对今后利用纳米光催化技术与活性炭纤维相结合用于净化空气的发展方向进行了展望。     

上海首次尝试使用道路涂料来消除空气中废气

上海市环保局己在复兴路隧道120m长的路面涂覆一种光催化涂料，经检测可吸收空气中约45％的有毒废气。这种光催化技术有望在上海得到推广应用。     

净化空气多功能内墙涂料的制备及其性质研究

加入纳米TiO2作为光催化粉体,对传统建筑内墙涂料进行改性,使之具有较强的净化空气、杀菌抑菌的功能。从分散剂用量的确定、纳米TiO2用量的确定、PVC的确定三个方面来提高涂料本身的性能。对其光催化氧化降解甲醛进行了初步测试表明,对室内有害气体污染有较大的改善作用。     

空气净化器有害物质二次污染研究

空气净化器是近年来家电市场上的新兴电器,是具有吸附、分解或转化各种空气污染物的功能的电器产品,可以有效提高空气清洁度,在很大程度上改善室内空气质量。但目前面上销售的空气净化器产品,大部分采用风机抽风+滤网过滤的净化模式,随着空气净化器的使用,可能造成对环境空气的二次污染。对多批次台空气净化器有害物质的二次污染进行测试研究,结果表明空气净化器的吸附净化到达一定程度后,PM₁₀与微生物无释放,而甲醛则有不同程度的释放。最后提出对空气净化器二次污染的相关建议及防护措施。     

1种净化空气功能的瓷砖出炉

近日．建材市场1种具有净化空气功能的瓷砖最新出炉。为了消除有害物质和气体对空气的污染．防止对人体健康的危害，海外一公司研制成功1种具有净化空气功能的瓷砖。这种瓷砖系多孔结构。能大量吸附有害的物质和气体，除去异味，达到净化空气的功能。     

介绍一种新型空气自净系统

本文通过介绍一种新型空气自净系统——Ｃｏｓａ＼Ｔｒｏｎ系统及有关应用标准、性能和实际应用效果，提出通过改善进入空调区域再循环空气（混有新风）送风的品质，来减少稀释空调区域污浊空气的新风量，不仅改善室内空气品质，同时达到节能效果。最后，提出应用Ｃｏｓａ＼Ｔｒｏｎ自净系统的一些看法，以供同行参考。     

空气相对湿度对空气净化器净化效果影响的实验研究

对4台空气净化器进行了实验研究,分析了不同相对湿度下空气净化器的现场净化效率、洁净空气量、有效净化效率和净化能效,以及细颗粒物(PM2.5)的自然衰减规律与净化衰减规律。结果显示:在相对湿度为35%～60%的范围内,滤网式空气净化器的现场净化效率随着相对湿度的增大而增大,而静电除尘式空气净化器的现场净化效率随着相对湿度的增大而减小;对于滤网式空气净化器,其洁净空气量及有效净化效率随着相对湿度的增大而增大;PM2.5的自然衰减速度随着相对湿度的增大逐渐加快,滤网式空气净化器对PM2.5的净化衰减速度随着相对湿度的增大而加快,静电除尘式空气净化器对PM2.5的净化衰减速度随着相对湿度的增大而逐渐放缓。     

空气-空气热泵与空气-水热泵的区别

空气-空气热泵的形式是最普通的空气源热泵形式，特别适用于由工厂制造的单元式热泵。在该类热泵中，热源（制冷运行时为冷却介质）和用作供热（冷）的介质均为空气。在该系统中，一个换热盘管作为蒸发器而另一个作为冷凝器。在制热循环时，被调的空气流过冷凝器而室外空气流过蒸发器，制冷剂流向改变后则成了制冷循环，被调空气流过蒸发器而室外空气流过冷凝器。[第一段]     

空气悬架性能分析

以1／4钢板弹簧悬架车辆和空气悬架车辆模型为仿真对象，建立模运动微分方程，模拟C级路面为随机输入，对模型进行了计算机仿真。研究结果表明：空气悬架车辆的车身加速度、悬架动挠度和车轮动载荷都有所降低，其操纵稳定性能和平顺性能明显优于钢板弹簧悬架车辆。     

空气净化器对室内粒子去除效果的实验研究

可吸入粒子是病毒细菌的载体,但通风空调系统往往仅对大粒子有明显的清除效果,为此空调和自然通风房问开始逐步使用空气净化器消除小粒子对人体健康的危害。本文通过对不同安放位置和不同工况条件下运行的空气净化器对室内粒子实际去除效率进行实验研究,结果表明,净化器的循环风量是影响粒子去除效率的主要原因。尽管高风速情况下净化器的粒子...     

Performance of ultraviolet photocatalytic oxidation for indoor air cleaning applications

Ultraviolet photocatalytic oxidation (UVPCO) systems for removal of volatile organic compounds (VOCs) from air are being considered for use in office buildings. Here, we report an experimental evaluation of a UVPCO device with tungsten oxide modified titanium dioxide (TiO2) as the photocatalyst. The device was challenged with complex VOC mixtures. One mixture contained 27 VOCs characteristic of office buildings and another comprised 10 VOCs emitted by cleaning products, in both cases at realistic concentrations (low ppb range). VOC conversion efficiencies varied widely, usually exceeded 20%, and were as high as approximately 80% at about 0.03 s residence time. Conversion efficiency generally diminished with increased airflow rate, and followed the order: alcohols and glycol ethers > aldehydes, ketones, and terpene hydrocarbons > aromatic and alkane hydrocarbons > halogenated aliphatic hydrocarbons. Conversion efficiencies correlated with the Henry's law constant more closely than with other physicochemical parameters. An empirical model based on the Henry's law constant and the gas-phase reaction rate with hydroxyl radical provided reasonable estimates of pseudo-first order photocatalytic reaction rates. Formaldehyde, acetaldehyde, acetone, formic acid and acetic acid were produced by the device due to incomplete mineralization of common VOCs. Formaldehyde outlet/inlet concentration ratios were in the range 1.9-7.2. PRACTICAL IMPLICATIONS: Implementation of air cleaning technologies for both VOCs and particles in office buildings may improve indoor air quality, or enable indoor air quality levels to be maintained with reduced outdoor air supply and concomitant energy savings. One promising air cleaning technology is ultraviolet photocatalytic oxidation (UVPCO) air cleaning. For the prototype device evaluated here with realistic mixtures of VOCs, conversion efficiencies typically exceeded the minimum required to counteract predicted VOC concentration increases from a 50% reduction in ventilation. However, the device resulted in the net generation of formaldehyde and acetaldehyde from the partial oxidation of ubiquitous VOCs. Further development of the technology is needed to eliminate these hazardous air pollutants before such a UVPCO device can be deployed in buildings.     

Development of a new photocatalytic oxidation air filter for aircraft cabin

A new photocatalytic oxidation air filter (PCO unit) has been designed for aircraft cabin applications. The PCO unit is designed as a regenerable VOC removal system in order to improve the quality of the recirculated air entering the aircraft cabin. The PCO was designed to be a modular unit, with four UV lamps sandwiched between two interchangeable titanium dioxide coated panels. Performances of the PCO unit has been measured in a single pass mode test rig in order to show the ability of the unit to decrease the amount of VOCs (toluene, ethanol, and acetone) entering it (VOCs are fed separately), and in a multipass mode test rig in order to measure the ability of the unit to clean the air of an experimental room polluted with the same VOCs (fed separately). Triangular cell panels have been chosen instead of the wire mesh panels because they have higher efficiency. The efficiency of the PCO unit depends on the type of VOCs that challenges it, toluene being the most difficult one to oxidise. The efficiency of the PCO unit decreases when the air flow rate increases. The multipass mode test results show that the VOCs are oxidized but additional testing time would be necessary in order to show if they can be fully oxidized. The intermediate reaction products are mainly acetaldehyde and formaldehyde whose amount depends on the challenge VOC. The intermediate reaction products are also oxidized and additional testing time would be necessary in order to show if they can be fully oxidized. The development of this new photocatalytic air filter is still going on. PRACTICAL IMPLICATIONS: The VOC/odor removing adsorbers are available for only a small proportion of aircraft currently in service. The photocatalytic oxidation (PCO) technique has appeared to be a promising solution to odors problems met in aircraft. This article reports the test results of a new photocatalytic oxidation air filter (PCO unit) designed for aircraft cabin applications. The overall efficiency of the PCO unit is function of the compound (toluene, ethanol, and acetone) that challenges the unit and toluene appears to be the most difficult compound to oxidize. Test results have shown the influence of the design of the PCO unit, the air flow rate and the type of UV on the efficiency of the PCO unit. The results obtained in this study represent a first attempt on the way to design a filter for VOC removal in cabin aircraft applications. The PCO technique used by the tested prototype unit is able to partially oxidized the challenge VOCs but one has to be aware that some harmful intermediate reaction products (mainly formaldehyde and acetaldehyde) are produced during the oxidation process before being partially oxidized too.     

Experimental research on photocatalytic oxidation air purification technology applied to aircraft cabins

The experiment presented in this report was performed in a simulated aircraft cabin to evaluate the air cleaning effects of two air purification devices that used photocatalytic oxidation (PCO) technology. Objective physical, chemical and physiological measurements and subjective human assessments were used for the evaluation. Comparisons were made between conditions with and without the PCO units installed in the re-circulated air system. Four groups of 17 subjects were exposed for 7 h to each test condition. Chemical analysis indicates that ethanol, isoprene and toluene were decomposed by oxidation in the PCO units tested. However, some intermediate products, such as formaldehyde and acetaldehyde, were detected. Physiological measurements did not show any significant effects of the two PCO units except that skin dryness was reduced by operating PCO unit 2. Both positive and negative effects of using PCO units on subjective assessments were observed after the first 3 1/4 hours of exposure. After 6 h of exposure, a positive effect of using either PCO unit on symptoms of dizziness and claustrophobia was observed.     

Effect of filter collection efficiency on the clean air delivery rate in an air cleaner

The performance of an air cleaner is evaluated by the clean air delivery rate (CADR), which is defined as the measure of the delivery of contaminant-free air. Herein, we conducted comparative analyses of various particulate air filters with various collection efficiencies. We installed each filter in identical commercial air cleaners to determine the effects of the collection efficiency on the CADR. Three different filters (E11, E12, and H13 classes) were prepared to determine the effects of the filter collection efficiency and pressure drop on the air cleaner performance (ie, the CADR). Based on experimental data, filters E11 and E12 had similar CADRs and flow rates. However, filter H13, which had the highest collection efficiency and the lowest flow rate, had the lowest CADR. This indicates that even if a filter with higher collection efficiency is installed in an air cleaner, the larger pressure drop causes a reduction in the air flow rate. The CADR value is widely distributed for a flow rate range for commercially available models; however, the collection efficiencies for most air cleaners on the market lie in a narrow range. Therefore, the flow rate has the most direct impact on the performance of a commercial air cleaner.     

舒适性空调空气过滤器效率计算方法

给出了舒适性空调空气过滤器效率的设计计算公式,分析了公式中各量的取值范围,以商场和办公室为例计算出了空气过滤器效率,并分析了计算结果。     

The effect of a photocatalytic air purifier on indoor air quality quantified using different measuring methods

The effect on indoor air quality of an air purifier based on photocatalytic oxidation (PCO) was determined by different measuring techniques: sensory assessments of air quality made by human subjects, Proton-Transfer-Reaction Mass Spectrometry (PTR-MS) and chromatographic methods (Gas Chromatography/Mass Spectrometry and High-Pressure Liquid Chromatography with UV detection). The experiment was conducted in a simulated office, ventilated with 0.6 h⁻¹, 2.5 h⁻¹ and 6 h⁻¹, in the presence of additional pollution sources (carpet, chipboard and linoleum). At the lowest air change rate, additional measurements were made with no pollution sources present in the office. All conditions were tested with the photocatalytic air purifier turned on and off. The results show that operation of the air purifier in the presence of pollutants emitted by building materials and furniture improves indoor air quality, as documented by sensory assessments made by human subjects. It also reduces concentrations of many chemical compounds present in the air as documented by the PTR-MS technique. For the lowest ventilation, results from measurements using the chromatographic methods have similar tendency, however many of the 50 compounds that were targeted for analysis were not detected at all, independent of whether the purifier was on or off. For the two conditions with higher ventilation the results were inconclusive.     

Achieving 'excellent' indoor air quality in commercial offices equipped with air-handling unit--respirable suspended particulate

A study was carried out to investigate the feasibility of achieving ultra low respirable suspended particulates (RSP) in commercial offices without major modification of existing ventilation systems by enhancing the particulates removal efficiency of existing central ventilation systems. Four types of filters which include pre-filters, cartridge filters, bag filters and high efficiency particulates air (HEPA) filters were tested in a commercial building in Causeway Bay. The results show that an RSP objective of <20 microg/m3 could be met by removing RSP from both the return air and outdoor air supply simultaneously. This level of performance is classed as 'excellent' by the Hong Kong Government, Environmental Protection Department. Filters with efficiency that exceed 80% placed both in the return air and outdoor air were sufficient to meet the objective. It is not necessary to install HEPA filters to achieve the 'excellent' class. The outdoor air filter has great influence on the steady state indoor RSP concentration while the effective cleaning rate is governed by the return air filter. Higher efficiency filters increased the static drop but the volume flow of the air fan was not affected significantly. The additional cost incurred was <5% of the existing operation cost. PRACTICAL IMPLICATIONS: This paper reports a field study of RSP control for an indoor office environment. The results are directly applicable to building service engineering in the design of ventilation systems using air-handling units. Field observations indicated that indoor RSP in an office environment could be suppressed below 20 microg/m3 within 1 h by the simultaneous filtration of outdoor air and return air. Outdoor air filtration has a great influence on the steady state indoor concentration and return air filtration governs the cleaning rate. It is believed that the results of this study could be extended to the cleaning of other indoor pollutants such as volatile organic compounds.     

基于活动强度的空气呼吸器耗气率预测

针对人员个性差异,合理预测空气呼吸器耗气时间,提出一种依据人员活动强度计算空气呼吸器耗气率的方法。按照人员的4 种活动强度等级,通过采集人员的空呼静止耗气率、个人动静心率比和空呼耗气率的数据,利用相关系数矩阵确定不同活动强度空呼耗气率的主要影响因素,以其主要影响因素为自变量,耗气率为因变量,建立基于活动强度计算空呼耗气率的回归模型。经验证,该模型具有较高的拟合度,对预测空气呼吸器的耗气率具有较好效果。     

室内空气品质改善措施

主要从民用建筑空调系统——全面通风、新风处理和新风质量、送风方式、空调设备、运行工况等方面探讨了如何防止病态建筑的产生,提高室内空气品质,从而使人们享受舒适的现代生活而不会被"病态建筑综合症"侵扰,并就此提出了改善室内空气品质应采取的措施和方法。     

空气换热器在冷却顶板空调系统中的节能潜力

分析计算了采用不同空气换热器组合方案时CC/DV系统和CC/MV系统的新风能耗,指出两个空气热回收装置组合使用可以消除新风再热能耗,但在夏季湿热地区,排风潜热回收比消除新风再热能耗更重要,应尽可能使用全热空气换热器。