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...     

地下空间空气负离子对人体的影响

在某地下建筑房间内进行一次试验以了解地下空间中负离子对人员的影响。试验中采用脑电、主观感觉调查和脉膊、血压以及智力测试方法。从试验结果统计分析后得到,由于负离子缺乏,人员脑电显示出α波减低,δ、θ波升高,且人员的精神感觉也有一些不良影响,可见这就是长期在地下工作人员感到压抑、烦恼、胸闷、疲乏的原因之一。用人工负离子可以改善这一状态,其离子浓度大约控制在2400～10000个/cm~3范围内。     

时刻为轿厢输送新鲜空气——高能正负离子空气净化器介绍

大多数人在提及电梯的节能环保时，都比较关注如何省电，如何采用环保的材料，而对于电梯轿厢这个每天数以千计，甚至万计的人出入的空间，其空气环境的污染却漠然视之。当年在SARS横行之时，人们对电梯空间曾经心有余悸，灾难过后人们不免又健忘起来。     

空气净化器去除颗粒物的洁净空气量衰减评价方法

我国室内空气污染日益严重,特别是随着室外颗粒物污染问题的加剧,室内颗粒物污染已成为社会关注的焦点问题。空气净化器是去除室内颗粒物的重要手段之一,然而空气净化器去除颗粒物的性能会随着使用而下降,目前缺乏快速、可行的方法测试这种性能衰减。提出了一种小型试验舱快速老化试验的空气净化器去除颗粒物的性能衰减快速测试方法,试验结果表明该方法简单可行,可有效测量空气净化器去除颗粒物的洁净空气量性能的衰减。     

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。     

动态法测定空气负离子浓度的研究

为探索环境因素、试验位置对负离子建材产品的影响,采用动态法检测产品的空气负离子浓度。试验结果表明,温湿度升高,距离越小,负离子浓度则越高,但不同范围变化幅度不同,幅度小则稳定性好,温湿度最好分别控制在(23±5)℃和(60±10)%,测试点位于试验高度为1.0 m、距离墙面0.3 m的位置。动态法检测能够客观反映现场负离子情况,可以给负离子建材产品的空气离子性能评价提供依据。     

空气中负离子浓度对过滤器捕集效率的影响

空气过滤净化器能够提高建筑空气品质,在越来越多的建筑安装了空气过滤器。因此,有必要对过滤器捕集效率的影响因素进行讨论。本文通过实验的方法,分析了空气中负离子浓度与过滤器捕集效率的关系。实验结果表明,空气中负离子浓度对过滤器存在增效的作用,这种增效作用在粒径小于0.5μm时很显著。本文实测条件下(风速0.6～1.5m/s),均存在10%左右的增效。     

高甲醛CADR空气净化器去除甲醛能力调查及分析

本文抽取16批次甲醛洁净空气量(CADR)不小于400 m~3/h、超出GB/T 18801-2015适用范围的空气净化器,针对14批次样机实测了甲醛洁净空气量、甲醛净化效率、甲醛净化能效、颗粒物洁净空气量等指标,对其甲醛去除性能进行了统一比较和评价。通过实测数据发现,92.9%的样机的甲醛CADR符合要求,实测值超过不低于标称值的90%,且只有两批次低于400 m~3/h,甲醛净化效率在78.4%～98.0%范围内,所有样机甲醛净化能效均达到高效级,71.4%的样机的甲醛CADR实测值达到了颗粒物CADR实测值的50%以上。数据表明市场对甲醛CADR值有了越来越高的需求,对空气净化器的净化技术提出了更高的要求。同时,国标GB/T 18801-2015有关气态污染物CADR测试范围的规定需要加快修订以适用社会需求及行业发展的需要,另外通过这次调查亦发现少数样机存在异味散发及过滤器长期存放失效问题。     

空气净化器净化性能测试方法综述

近年来,室内空气质量引起人们的广泛重视,空气净化器作为去除室内空气污染物的有效产品,逐渐进入万众家庭,而产品对污染空气的净化能力,成为消费者普遍关注的热点问题.本文调研了中国、美国、日本、韩国、加拿大等国家发布的空气净化器性能测试方法标准或技术文件,梳理总结出净化性能相关的测试方法,对评价内容和评价参数进行了比对.从科...     

空气净化器运行优化的模拟研究

采用模拟手段,开展了居住建筑通风净化运行策略优化的分析研究,并探讨了室内PM2.5初始质量浓度、室外PM2.5污染等级、房间通风换气量、房间容积、空气净化器连续和间歇运行方式等的影响特性及这些影响因素之间的相互作用.结果 表明,在室外PM2.5污染等级为严重、重度和中度时,应尽可能关窗以减少通风换气量,而在轻度和良时,...     

Negative ions offset cardiorespiratory benefits of PM2.5 reduction from residential use of negative ion air purifiers

Negative ion air purifiers (NIAPs), as a less costly alternative to the HEPA filtration, have been increasingly deployed in China and potentially elsewhere. While reducing indoor concentrations of fine particulate matter (PM_2.5), NIAPs generate massive amounts of negative ions that may be of health concern. We performed week-long interventions with NIAPs in the dormitories of 56 healthy college students living in Beijing. In a randomized order, each student underwent a true and a sham NIAP session. Cardiorespiratory outcomes were measured before and after each session. The use of true NIAPs reduced indoor PM_2.5 concentrations significantly, while notably increased negative ion levels. Increases in PM_2.5 and negative ion (NI) exposure were independently associated with increased urinary concentration of malondialdehyde, a biomarker of systemic oxidative stress, resulting in a null net effect of NIAP on malondialdehyde. Likewise, no significant net effects of NIAPs were observed for other outcomes indicative of lung function, vascular tone, arterial stiffness, and inflammation. Our findings suggest that negative ions, possibly along with their reaction products with the room air constituents, adversely affect health. The downsides do not support the use of NIAPs as a health-based mitigation strategy to reduce PM_2.5 exposure, especially in residences with PM_2.5 concentrations that are not extremely high.     

防烟空气幕性能测试研究

在理论与实验研究的基础上完成了防烟空气幕性能测试研究，得到了外加动力防烟空气幕与自带动力防烟空气幕风量、风速与功率之间的关系曲线。     

Evaluation of ionic air purifiers for reducing aerosol exposure in confined indoor spaces

Numerous techniques have been developed over the years for reducing aerosol exposure in indoor air environments. Among indoor air purifiers of different types, ionic emitters have gained increasing attention and are presently used for removing dust particles, aeroallergens and airborne microorganisms from indoor air. In this study, five ionic air purifiers (two wearable and three stationary) that produce unipolar air ions were evaluated with respect to their ability to reduce aerosol exposure in confined indoor spaces. The concentration decay of respirable particles of different properties was monitored in real time inside the breathing zone of a human manikin, which was placed in a relatively small (2.6 m3) walk-in chamber during the operation of an ionic air purifier in calm air and under mixing air condition. The particle removal efficiency as a function of particle size was determined using the data collected with a size-selective optical particle counter. The removal efficiency of the more powerful of the two wearable ionic purifiers reached about 50% after 15 min and almost 100% after 1.5 h of continuous operation in the chamber under calm air conditions. In the absence of external ventilation, air mixing, especially vigorous one (900 CFM), enhanced the air cleaning effect. Similar results were obtained when the manikin was placed inside a partial enclosure that simulated an aircraft seating configuration. All three stationary ionic air purifiers tested in this study were found capable of reducing the aerosol concentration in a confined indoor space. The most powerful stationary unit demonstrated an extremely high particle removal efficiency that increased sharply to almost 90% within 5-6 min, reaching about 100% within 10-12 min for all particle sizes (0.3-3 microm) tested in the chamber. For the units of the same emission rate, the data suggest that the ion polarity per se (negative vs. positive) does not affect the performance but the ion emission rate does. The effects of particle size (within the tested range) and properties (NaCl, PSL, Pseudomonas fluorescens bacteria) as well as the effects of the manikin's body temperature and its breathing on the ionic purifier performance were either small or insignificant. The data suggest that the unipolar ionic air purifiers are particularly efficient in reducing aerosol exposure in the breathing zone when used inside confined spaces with a relatively high surface-to-volume ratio. PRACTICAL IMPLICATIONS: Ionic air purifiers have become increasingly popular for removing dust particles, aeroallergens and airborne microorganisms from indoor air in various settings. While the indoor air cleaning effect, resulting from unipolar and bipolar ion emission, has been tested by several investigators, there are still controversial claims (favorable and unfavorable) about the performance of commercially available ionic air purifiers. Among the five tested ionic air purifiers (two wearable and three stationary) producing unipolar air ions, the units with a higher ion emission rate provided higher particle removal efficiency. The ion polarity (negative vs. positive), the particle size (0.3-3 microm) and properties (NaCl, PSL, Pseudomonas fluorescens bacteria), as well as the body temperature and breathing did not considerable affected the ionization-driven particle removal. The data suggest that the unipolar ionic air purifiers are particularly efficient in reducing aerosol exposure in the breathing zone when they are used inside confined spaces with a relatively high surface-to-volume ratio (such as automobile cabins, aircraft seating areas, bathrooms, cellular offices, small residential rooms, and animal confinements). Based on our experiments, we proposed that purifiers with a very high ion emission rate be operated in an intermittent mode if used indoors for extended time periods. As the particles migrate to and deposit on indoor surfaces during the operation of ionic air purifiers, some excessive surface contamination may occur, which introduces the need of periodic cleaning these surfaces.     

Wind tunnel-based testing of a photoelectrochemical oxidative filter-based air purification unit in coronavirus and influenza aerosol removal and inactivation

Recirculating air purification technologies are employed as potential means of reducing exposure to aerosol particles and airborne viruses. Toward improved testing of recirculating air purification units, we developed and applied a medium-scale single-pass wind tunnel test to examine the size-dependent collection of particles and the collection and inactivation of viable bovine coronavirus (BCoV, a betacoronavirus), porcine respiratory coronavirus (PRCV, an alphacoronavirus), and influenza A virus (IAV), by a commercial air purification unit. The tested unit, the Molekule Air Mini, incorporates a MERV 16 filter as well as a photoelectrochemical oxidating layer. It was found to have a collection efficiency above 95.8% for all tested particle diameters and flow rates, with collection efficiencies above 99% for supermicrometer particles with the minimum collection efficiency for particles smaller than 100 nm. For all three tested viruses, the physical tracer-based log reduction was near 2.0 (99% removal). Conversely, the viable virus log reductions were found to be near 4.0 for IAV, 3.0 for BCoV, and 2.5 for PRCV, suggesting additional inactivation in a virus family- and genus-specific manner. In total, this work describes a suite of test methods which can be used to rigorously evaluate the efficacy of recirculating air purification technologies.     

氨在空调制冷领域的应用

在热力特性、环境安全特性及技术成熟性等方面比较了氨和其他几种工质，介绍了氨在空调制冷领域应用中几项关键技术的发展，以及氨系统目前的应用情况。     

室内空气质量控制策略初探

由于经济快速增长及生产活动导致的大气污染问题越来越严重,且是一个不可能在短期内解决的问题,现代人80%-90%的时间在室内度过,因此室内的空气品质对人体健康有着很大的影响。室外雾霾天气及室内材料散发的甲醛、TVOC等污染物,使我国室内空气环境处于内忧外患的状态。本文总结了目前常见的新风系统形式及典型的气流分布模式,总结了市面上常用的过滤器类型及空气净化器类型,为绿色建筑及被动房建设提供技术参考。     

柜式空调机在矩形空间使用效果的实验研究

实验研究结果表明,送风方向和送风速度挡的合理设置能使空调器达到良好的使用效果,柜式空调机组合工作时,两台空调机的相对位置、导风板的旋转角和出口风速对室内平均温度的影响较大。在合理的风速和机组组合下,送风方向与垂直面成90°以上角时,空调房间的温度分布更趋均匀。