Flue gas treatability studies: a tool for techno-economic control of industrial air pollution

Air pollution problems in developing countries have gained larger fraction in the last decade especially due to non functioning and non implementation of effective air pollutioncontrol devices in industries. In industrial wastewater management, adequate treatability studies are conducted to arrive at a techno-economic treatment option. However no suchstudies were done for reducing air pollution or emission fromindustries until now in India. Little information was availableabout such studies in other countries. This article provides information about a novel technique known asflue gas treatability studies and to undertake such studies, a pilot scale system is installed in Air Pollution Control Divisionof M/s National Environmental Engineering research Institute, NEERI, Nagpur-20, India. This study is a tool for techno-economicselection of air pollution control systems specially for small/medium scale industrial emissions.     

An Assessment on Variation of Sulphur Dioxide and Particulate Matter in Erzurum (Turkey)

Sulphur dioxide and PM₁₀ levels are investigated in Erzurum during the periods of 1990–2000 heating season to assess air pollution level. For that reason, emissions of sulphur dioxide and particulate matter were calculated by using consumption of fuels and Turkish emission factors. These emission values were evaluated together with air pollution levels, which were measured at six stations in Erzurum atmosphere during 1990–2000 winter periods. Results reveal that in 1990–1994 heating period, there is an increasing trend in the emissions and air pollution levels over Erzurum, and the air quality limits were not met. The daily 24 h limit (short-term limit) was exceeded 127 days in 1992–1993 winter period. The reason for this increase was found to be the switching to use of low-quality fossil fuels instead of cleaner ones. Results also indicated that there was a considerable decrease in emissions of air pollutants and air pollution levels after 1995. This can be explained by the consumption of more high-quality fossil fuels. The correlation coefficient of SO₂ with PM₁₀ is obtained as r² = 0.85, which is a high value supporting the idea that both pollutants are emitted from the same source.     

Measurements of Ozone Concentrations in Zagreb

Ozone concentrations were measured in Zagreb at four sites from May 1999 to April 2001 in order to categorize the air quality with respect to ozone. In the summer of 2000, the ozone measurements were also extended to four sites in the suburbs of Zagreb. Methods of active and passive sampling with nitrite ion as a reagent were used. In the northern part of the town ozone was analyzed by an automatic device. Automatic device measurements in the years 1999 and 2000 showed that hourly averages of ozone concentrations did not exceed the Croatian recommended value of the 98th percentile (180 g m^–3). Over the two-year period, 24-h averages occasionally exceed 110 g m^–3 in city center and in the northern part of the town. Regardless of these isolated examples, ozone was well within acceptable concentrations. Ozone concentrations measured in summer 2000 were higher in the suburbs of Zagreb than in the city. The 98th percentile values higher than 110 g m^–3 were recorded at three sites.     

A Metamodeling Approach for Integrated Assessment of Air Quality Policies

A method is proposed to build integrated models (also called Metamodels) aimed at quantifying the economic efficiency of air quality policies. This Metamodeling approach is based on the coupling of two complementary models, that operate at different scales in space and time, and which represent the economic and the physical and chemical processes, respectively. The joint consideration of the physico-chemical and techno-economic structure of the pollution control problems permits a comprehensive evaluation of air pollution abatement strategies. The motivating pollution control problems include urban-regional air quality management through efficient energy and traffic control policies. A pilot study, exploiting data collected in the Geneva canton (Switzerland), is used to demonstrate the potential of the approach.     

MERCURY EMISSION INVENTORY IN ONTARIO

Mercury is released to the environment from various anthropogenic and natural sources. This work is a compilation of mercury emissions from anthropogenic sources in Ontario, Canada. The goal of our study was to identify all sources of mercury, and develop an emission inventory of anthropogenic mercury in Ontario. The result of our investigation revealed that combustion of fossil fuels and emissions from landfill sites are two primary sources of mercury to the atmosphere. Other sources of significance are emissions from waste incinerators, various industrial activities, and cement production. Total mercury emission in Ontario is estimated as 4100 kg per year.     

光离子化检测器便携式气相色谱仪快速测定空气中苯系物

本文研究了使用光离子化检测器便携式气相色谱仪，直接测定空气中ｍｇ／ｍ３级苯系物（苯、甲苯、乙苯、邻、间、对位的二甲苯及异丙苯）的快速分析方法。方法的线性范围为０～１００ｍｇ／ｍ３，相关系数均在０．９９９以上，方法的变异系数分别为２．９～１２．５％（５ｍｇ／ｍ３），３．４～７．９％（３０ｍｇ／ｍ３），方法最低检测限达０．２～１．０ｍｇ／ｍ３。     

大气CO2浓度升高对农田生态系统的影响

自由大气CO2浓度升高(简称FACE,即Free A ir CO2Enrichment)对陆地生态系统的影响是全球变化研究中的一个热点。综述了FACE条件下,农田土壤植物生物量质量变化和土壤微生物对植物的反馈作用,以及土壤痕量气体排放的趋势变化。     

Preparation of rare-earth metal complex oxide catalysts for catalytic wet air oxidation

Catalytic wet air oxidation (CWAO) is one of the most promising technologies for pollution abatement. Developing catalysts with high activity and stability is crucial for the application of the CWAO process. The Mn/Ce complex oxide catalysts for CWAO of high concentration phenol-containing wastewater were prepared by coprecipitation. The catalyst preparation conditions were optimized by using an orthogonal layout method and single-factor experimental analysis. The Mn/Ce serial catalysts were characterized by Brunauer-Emmett-Teller (BET) analysis and the metal cation leaching was measured by inductively coupled plasma torch-atomic emission spectrometry (ICP-AES). The results show that the catalysts have high catalytic activities even at a low temperature (80°C) and low oxygen partial pressure (0.5 MPa) in a batch reactor. The metallic ion leaching is comparatively low (Mn<6.577 mg/L and Ce<0.6910 mg/L, respectively) in the CWAO process. The phenol, COD_Cr, and TOC removal efficiencies in the solution exceed 98.5% using the optimal catalyst (named CSP). The new catalyst would have a promising application in CWAO treatment of high concentration organic wastewater. Translated from Techniques and Equipment for Environmental Pollution Control, 2005, 6(2): 40–44 [译自: 环境污染治理技术与设备]     

和田绿洲沙尘暴物质输送路径及其对大气环境质量的影响

为了研究来自不同方向的沙尘暴对和田绿洲大气环境质量的影响，本文利用HYSPLIT后向轨迹模型和NCEP的GDAS全球气象要素数据，将和田绿洲西北部的墨玉县城作为模拟受点（37.26°N，79.72°E），计算2016年1月1日—2018年12月31日发生的每一次沙尘天气期间逐日18：00（世界时）36 h后向气流轨迹，轨迹计算起始高度设置为500 m，并结合相应的PM_2.5、PM₁₀、SO₂、NO₂、CO、O₃浓度监测数据进行聚类分析，研究抵达该地区的沙尘暴的主要移动轨迹和污染物输送路径.同时，运用潜在源贡献因子分析法（PSCF）和权重污染轨迹分析法，分析了沙尘暴期间不同气流轨迹对墨玉县污染物浓度的影响，识别大气污染物的潜在源区，揭示不同源区对污染物浓度的贡献差异.结果表明，影响和田绿洲（墨玉县）的沙尘暴主要来自西北（WN）、北（N）、东北（EN）和东（E）4个方向；其中，来自东部的沙尘天气频率最高（60.2%），但主要以浮尘天气为主；扬沙和强沙尘暴主要来自西部方向，54.48%的强沙尘暴和38.53%的扬沙来自西和西北方向.不同沙尘源区和不同传输路径上的沙尘气溶胶对和田绿洲大气环境的影响不一样.沙尘天气期间，大气PM_2.5和PM₁₀的平均浓度相当于无沙尘天气期间的3~5倍，但对SO₂、NO₂、CO、O₃质量浓度的影响不大；由西向东和由北向南的沙尘暴对墨玉县PM_2.5和PM₁₀质量浓度的贡献率最大；由东向西的沙尘暴由于路过和田市和洛浦县等工业污染源区，此簇沙尘暴气团将该区域SO₂、NO₂、CO等污染颗粒携带到墨玉县，因此，东-东南（E-ES）方向的沙尘暴对SO₂、NO₂、CO的贡献率分别为15.56%、20.55%和21.57%.本文定量印证了沙尘暴对和田绿洲大气环境质量的影响，可为绿洲区沙尘暴研究提供参考.     

Optimization of C/N ratio for preparation of protein-rich and multi-enzymes feed thallus through synergic fermentation of mixed distillers'grains

A new procedure of determining optimal C/N (the rate of carbon source to nitrogen source) of mixed distillers' grains for combined bacteria synergic fermentation is established. At the same time an improved method evaluating bacteria growth, called method of dry cell weighing by filtering is developed. For each combination of C and N , their initial and residual contents before and after fermentation respectively are determined. Then followed the calculation of utilization of C and N sources by the compound bacteria. The optimal C/N is finally located from among the utilization of C and N of several combinations and the weight of produced mass of oven-dried thallus The conditions of fermentation are: inoculum size 10%, temperature 30.0℃, rotational speed 170 r/min, shake culture time 48h. The best results obtained from orthogonal experiments are: maximum mass of oven dried thallus is 14.693g in a liter liquid medium, maximum utilization rate of carbon source is 98.13% and maximum utilization rate of nitrogen is 78.14%. Optimal C/N is 5.1.