徐州市电磁辐射环境的污染现状调查及评价

调查了徐州市电磁辐射污染源的状况,分析了其电磁辐射环境质量的现状,并对全市电磁辐射环境质量进行了评价,指出了分析工作中存在的问题,提出了防治对策。     

废旧计算机CRT监视器的管理和资源化技术

分析了废旧计算机CRT监视器的材料组成 ,并且阐明了它对环境和人体健康的潜在危害 ,同时比较了国内外相关管理现状 ,总结了目前已有的资源化技术 ,主要是拆解技术 ,并且介绍了目前国内外的资源化实践 ,并提出有关建议。     

宝应县畜禽养殖业的现状调研及污染防治对策

调查了宝应县畜禽养殖业的发展现状及分布情况,阐述了该县畜禽养殖业的污染防治状况,分析了污染防治中存在的主要问题,并提出了当地畜禽养殖业污染防治的基本思路和治理措施,对贯彻落实防治措施提出了建议。     

三索式格栅除污机电控系统的国产化设计

介绍了三索式格栅除污机的工艺及控制原理 ,提出了一些以低价的元器件代替高价元器件的方案 ,设计了国产化的电控系统 ,使整机完全实现国产化 ,降低了系统的成本 ,同时便于调试和维修。     

生态工业园区及其建设

生态工业园区是实现生态工业和工业生态学的重要途径 ,代表了未来工业生态系统发展方向。本文从生态工业园区的概念出发 ,分析了生态工业园区的基本特征与功能 ,阐述了生态工业园区的类型及其建设的重点内容 ,介绍了生态工业园区建设实践 ,提出了生态工业园区建设的对策与措施     

陕西神木大柳塔洗煤厂煤泥水快速沉降剂试验研究

为了解决陕西神木大柳塔洗煤厂煤泥水的快速沉降和洗水循环再利用 ,在深入研究原煤泥水处理工艺技术效能的基础上 ,研究和发展了一种新型高效、经济的煤泥水处理工艺技术 ,合成了一种快速沉降剂。经过反复试验研究 ,使得原煤泥水系统有了极大改善 ,实现了洗水闭路循环和煤泥厂内回收 ,降低了药耗 ,缩短了反应时间 ,达到了快速沉降的目的。     

氧化锌法处理低浓度SO_2烟气的模拟实验研究

文中介绍了氧化锌法脱硫的基本原理,总结了国内外研究及应用现状,同时详细叙述了模拟实验采用的流程、主要仪器,着重分析了不同SO2浓度下的吸收率以及亚硫酸锌的氧化率与氧化时间、浆液温度的关系,提出了实验过程中发现的问题及可采取的措施,为后期中试以及工业化应用提供了设计依据。     

含油废水处理技术进展

概述了含油废水的来源、特征、危害及分类,介绍了重力机械法、气浮法、絮凝法、吸附法、生化法等处理方法的原理和进展,并比较总结了他们的适用范围和优缺点,最后简述了含油废水处理的最新进展,提出了含油废水处理技术的一些建议和展望。     

堆肥过程中腐殖酸的生成演化及应用研究进展

腐殖酸是堆肥过程中生成的最具代表性的次生产物,对堆肥的稳定性、腐熟度等性质有重要影响。介绍了堆肥过程中腐殖酸的生成及动态变化,分析了堆肥腐殖酸的结构特性,归纳了堆肥过程中腐殖酸生成机制,并在此基础上探讨了影响堆肥腐殖酸生成演化的主要影响因素,总结了堆肥腐殖酸作为堆肥腐熟度指标、表面活性物质、吸附剂等的应用情况,最后提出了当前堆肥腐殖酸研究中存在的主要问题,并对未来的研究方向进行了展望。     

中国环境影响评价中的公众参与问题浅析

简述了环境影响评价中,公众参与的概念,分析了公众参与的必然性及其发展历程,同时也指出了目前环境影响评价中,公众参与存在的问题,通过分析,提出了若干建议。     

Determination of secondhand smoke leakage from the smoking room of an Internet café

Although Internet cafes have been designated as nonsmoking areas in Korea, smoke-free legislation has allowed the installation of indoor smoking rooms. The purposes of this study were to determine secondhand smoke (SHS) leakage from an Internet café smoking room and to identify factors associated with SHS leakage. PM_2.5 (particulate matter with an aerodynamic diameter ≤2.5 μm) mass concentrations were measured simultaneously both inside and outside the door to the smoking room. During each measurement, a field technician observed how long the smoking room door was opened and closed, the direction of door opening, and the number of smokers. A multivariate linear regression model was used to identify the causality of SHS leakage from the smoking room. A time series of PM_2.5 concentrations both inside and outside the door to the smoking room showed a similar trend. SHS leakage was significantly increased because of factors associated with the direction of the smoking room door being opened, the duration of how long the smoking room door was opened until it was closed, and the average PM_2.5 concentration inside the smoking room when the door was opened. SHS leakage from inside the smoking room to outside the smoking room was evident especially when the smoking room door was opened. Since the smoking room is not effective in preventing SHS exposure, the smoking room should be removed from the facilities to protect citizens from SHS exposure through revision of the current legislation, which permits installation of a smoking room.

Implications: This paper concerns secondhand smoke (SHS) leakage from indoor smoking room. Unlike previous studies, the authors statistically analyzed the causality of PM_2.5 concentration leakage from a smoking room using time-series analysis. Since the authors selected the most common smoking room, the outcomes could be generalized. The study demonstrated that SHS leakage from smoking room and SHS leakage were clearly associated with door opening. The finding demonstrated ineffectiveness of smoking room to protect citizens and supports removal of indoor smoking room.     

Effectiveness of In-Room Air Filtration and Dilution Ventilation for Tuberculosis Infection Control

Abstract

Tuberculosis (TB) is a public health problem that may pose substantial risks to health care workers and others. TB infection occurs by inhalation of airborne bacteria emitted by persons with active disease. We experimentally evaluated the effectiveness of in-room air filtration systems, specifically portable air filters (PAFs) and ceiling-mounted air filters (CMAFs), in conjunction with dilution ventilation, for controlling TB exposure in high-risk settings. For each experiment, a test aerosol was continuously generated and released into a full-sized room. With the in-room air filter and room ventilation system operating, time-averaged airborne particle concentrations were measured at several points. The effectiveness of in-room air filtration plus ventilation was determined by comparing particle concentrations with and without device operation. The four PAFs and three CMAFs we evaluated reduced room-average particle concentrations, typically by 30% to 90%, relative to a baseline scenario with two air-changes per hour of ventilation (outside air) only. Increasing the rate of air flow recirculating through the filter and/or air flow from the ventilation did not always increase effectiveness. Concentrations were generally higher near the emission source than elsewhere in the room. Both the air flow configuration of the filter and its placement within the room were important, influencing room air flow patterns and the spatial distribution of concentrations. Air filters containing efficient, but non-high efficiency particulate air (HEPA) filter media were as effective as air filters containing HEPA filter media.     

Indoor pollutant mixing time in an isothermal closed room: an investigation using CFD

We report on computational fluid dynamics (CFD) predictions of mixing time of a pollutant in an unventilated, mechanically mixed, isothermal room. The study aims to determine: (1) the adequacy of the standard Reynolds Averaged Navier Stokes two-equation (k−) turbulence model for predicting the mixing time under these conditions and (2) the extent to which the mixing time depends on the room airflow, rather than the source location within the room. The CFD simulations modeled the 12 mixing time experiments performed by Drescher et al. (Indoor Air 5 (1995) 204) using a point pulse release in an isothermal, sealed room mechanically mixed with variable power blowers. Predictions of mixing time were found in good agreement with experimental measurements, over an order of magnitude variation in blower power. Additional CFD simulations were performed to investigate the relation between pollutant mixing time and source location. Seventeen source locations and five blower configurations were investigated. Results clearly show large dependence of the mixing time on the room airflow, with some dependence on source location. We further explore dependence of mixing time on the velocity and turbulence intensity at the source location. Implications for positioning air-toxic sensors in rooms are briefly discussed.     

Measurement of total site mercury emissions from a chlor-alkali plant using ultraviolet differential optical absorption spectroscopy and cell room roof-vent monitoring

This technical note describes a United States Environmental Protection Agency (U.S. EPA) measurement project to determine elemental mercury (Hg⁰) emissions from a mercury cell chlor-alkali (MCCA) facility in the southeastern U.S. during a 53-day monitoring campaign in the fall of 2006. The optical remote sensing (ORS) area source measurement method EPA OTM 10 was used to provide Hg⁰ flux data for the site. These results are reported and compared with cell room roof-vent monitoring data acquired by the facility for similar time periods. The 24-h extrapolated mercury emission rate estimates determined by the two monitoring approaches are shown to be similar with overall averages in the 400 g day^?1 range with maximum values around 1200 g day^?1. Results from the OTM 10 measurements, which include both cell room emissions and potential fugitive sources outside the cell room, are shown to be approximately 10% higher than cell room monitoring results indicating that fugitive emissions from outside the cell room produce a small but measurable effect for this site.     

Revised air-exchange efficiency considering occupant distribution in ventilated rooms

Air-exchange efficiency is widely used to indicate the ventilation effect and indoor air quality in ventilated rooms. However, it does not take occupant distribution in the room into account and is thus limited. In this paper, a revised air-exchange efficiency (occupant air-exchange efficiency) that differentiates between different zones by considering different occupancy in each zone is developed. Results from studies of a large-space ventilation case, a personalized ventilation case, and a displacement ventilation case show that occupant air-exchange efficiency can better be used to evaluate the ventilation effect of a room.     

基于CFD的污泥脱水机房恶臭扩散分布规律研究

污泥脱水机房是污水处理厂恶臭污染最严重的处理单元之一,其恶臭污染危害工作人员和周边居民身体健康。为研究脱水机房恶臭扩散分布规律,运用计算流体动力学（computational fluid dynamics, CFD）理论并采用其商用软件FLUENT对脱水机房主要恶臭污染物之一的硫化氢扩散分布进行数值模拟。案例研究了3种典型情景下的硫化氢扩散分布。结果表明,不同通风条件对脱水机房硫化氢扩散分布影响较大。在进行脱水机房设计时,应将脱水机布置于夏季最多风向的下方向,并靠近排风口,使恶臭污染物在最短的路径上排除出去,还应考虑机房其他布置,使工作人员经常接触和经过的地方位于低浓度区。     

Potential exposure of children and adults to cypermethrin following use of indoor insecticide foggers

The magnitude and distribution of cypermethrin from total release, over-the-counter foggers was studied in a test room and in residences to facilitate evaluation of regulatory exposure algorithms and new human exposure assessments based upon urine biomonitoring. Surface residue (SR) was evenly distributed in a small test room (3.6 μ g cypermethrin/cm²) where thorough mixing of the aerosol occurred. In a residence SR was significantly affected by room size and distance from the fogger. Air levels in the residence were as high as 30 μ g cypermethrin/cm³ after 4.5 h. The availability of surface residues was measured with an automated surface cotton cloth wipe and ethyl acetate extraction. Only 5% of the SR was available from nylon carpet. Tile, wood and linoleum resulted in 30, 10, and 10% of SR being available, respectively. These data are used to estimate cypermethrin exposure of children and adults for comparison with existing regulatory reference dosages and exposure assessments based upon biomonitoring.     

Effect of interior door position on room-to-room differences in residential pollutant concentrations after short-term releases

Residential interior door positions influence the pollutant concentrations that result from short-term indoor sources, such as cigarettes, candles, and incense. To elucidate this influence, we reviewed past studies and conducted new experiments in three residences: a single-story 714 m³ ranch-style house, a 510 m³ two-story split-level house, and a 200 m³ two-story house. During the experiments, we released sulfur hexafluoride or carbon monoxide tracer gas over short periods (≤30 min) and measured concentrations in the source room and at least one other (receptor) room for various interior door opening positions. We found that closing a door between rooms effectively prevented transport of air pollutants, reducing the average concentration in the receptor room relative to the source room by 57–100% over exposure periods of 1–8 h. When intervening doors were partially or fully open, the reduction in average concentrations ranged from 3% to 99%, varying as a function of door opening width and the distance between source and receptor rooms.     

Determinants of wastewater treatment expenditure of Austrian communities

Wastewater treatment services are bound to rather strict environmental regulations. However, as the broad range of wastewater expenditure of communities shows, there is room for discretionary policies of communities. The current paper explores wastewater treatment expenditure of Austrian communities by employing a cross-section econometric model. To a significant extent, demographic, geographic and technological variables determine wastewater expenditure with only little possibilities to influence these expenditure. Yet there is also some limited room for short-term discretionary policies with respect to the organisational setting. If communities can organise their wastewater treatment in a collective way, they can influence their expenditure significantly.     

Revised Air-Exchange Efficiency Considering Occupant Distribution in Ventilated Rooms

Abstract

Air-exchange efficiency is widely used to indicate the ventilation effect and indoor air quality in ventilated rooms. However, it does not take occupant distribution in the room into account and is thus limited. In this paper, a revised air-exchange efficiency (occupant air-exchange efficiency) that differentiates between different zones by considering different occupancy in each zone is developed. Results from studies of a large-space ventilation case, a personalized ventilation case, and a displacement ventilation case show that occupant air-exchange efficiency can better be used to evaluate the ventilation effect of a room.