浅析餐饮业油烟污染及控制方法

针对餐饮业油烟污染问题,阐述了餐饮业油烟气的形成过程、危害以及目前国内市场上使用油烟净化方法：冷凝法、旋风分离法、活性炭吸附、静电法、液体洗涤法等工艺及优缺点,为科学防治油烟污染提供了借鉴。     

气相色谱法测定给水中三卤甲烷的方法

本文介绍了用毛细管柱气相色谱法定量测定给水中三卤甲烷（氯仿、一溴二氯甲烷、二溴一氯甲烷和溴仿）及四氯化碳的方法。其色谱条件是：检测器（ＥＣＤ）温度：３４５℃;色谱柱：ＨＰ５（２５ｍ×０３２ｍｍ×１０５μｍ）柱;进样口温度：２５０℃。该方法的最小检出下限分别为：氯仿０１μｇ／ｌ、四氯化碳０１μｇ／ｌ、一溴二氯甲烷０２μｇ／ｌ、二溴一氯甲烷０２μｇ／ｌ和溴仿０４μｇ／ｌ。     

比色分析中加标回收率计算一方法的讨论

比色分析中加标回收率计算一方法的讨论沈晓平（江苏南通市环境监测站,南通２２６００６）当试样减空白吸光值（Ａｃｔ＃－Ａｑ白）＞截距ａ时,试样加标回收率可用吸光值（Ａｔ;标一Ａ试样）直接进行计算,用干实际样品计算简便快捷：（ＡＭｏ—Ａ;ｆｏ）／ｂ当（的样...     

燃煤锅炉除尘器的除尘效率分析

1　除尘器的主要类型及除尘效率分析1 1　除尘器类型以除尘器在除尘过程中是否使用水或其他液体 ,分为湿式除尘器和干式除尘器。依据除尘机理不同 ,又可分为 4类 :1 1 1　机械式除尘器 ,如单管旋风除尘器、多管旋风除尘器、重力沉降室、惯性除尘器等。含有悬浮尘粒的运载气体进入旋风除尘器后 ,经过向上和向下两个有界涡旋运动 ,离心力将较重的粒子甩向器壁 ,而向上涡旋运动则将净化的气体带出器外。旋风子的材料有铸铁和工业陶瓷等。1 1 2　湿式除尘器 ,有喷淋塔、文丘里式洗涤器等。这类除尘器是使含尘气体与水密切接触 ,利用水滴与…     

电导率计算方法的再改进

电导率测试合格率处于75％的低水平上,究其原因,很大程度是计算公式中的温度校正常数a不适应所有温度所致。文献［1］和文献［2］从不同角度对计算方法作了改进。在精度上有了很大程度的提高,但较繁琐,本文提出了对温度校正常数a直接作修正的方法。1温度校正常数a的测定方法参考温度系数的测定和温度校正方法［3］,考虑到离子浓度等因素对电导率温度校正常数a的影响,选择4个有代表性的KCI标准样品及两个实际样品,逐一测定各温度下的电导率,计算出各温度的常数a（6个样品25℃时电导率分别为1#：111900μs／cm、2＃：12900μs／cm、…     

常州城区秋冬季黑炭气溶胶的浓度变化特征

根据常州市2012年9月-2013年1月的黑炭气溶胶（Black Carbon,以下简称BC）在线监测数据及常规气象资料,分析了BC在秋冬季不同时间段的变化特征及气象要素对BC的影响。结果表明,常州秋冬季BC平均值为5．17（1．48～17．02）μg／m^3,主要集中在1．00斗μg／m^3～7．50μg／m^3,冬季较高于秋季,小时均值最大值达33．87μg／m^3;BC本底值为3．50μg／m^3;1月份BC日均值变化幅度最大,发生高污染的频率最高。Bc的日变化具有明显的双峰结构,一天中最大浓度多出现在上午06：00-09：00,特殊天气条件下,BC小时值存在不同的分布情况;BC在不同风向的输送条件下有明显的不同,偏东北方向过来的气团易造成BC高污染。     

BOD_5测试结果的简便计算

ＢＯＤ_５测试结果的简便计算韩子兴（中国石化镇海炼化公司环保处,宁波３１５２０７）本文将稀释倍数引入计算式,经数学变换得出简便的计算通式：ＢＯＤＳ一〔凸Ｄ一（１—１／Ｃ）凸Ｂ）ＸＣ一ＣＸＡＮ一（Ｃ—１）Ｘ凸Ｂ式中,Ｃ为稀释倍数（Ｃ。试验水样总体积／样...     

COD_（Mn）测定中K对Vo的影响

ＣＯＤＭｎ测定中Ｋ对Ｖｏ的影响张亚鸾李益群（江苏如皋市环境监测站,如皋２２６５００）ＣＫＭｎＯ４：高锰酸钾的摩尔浓度（ｍｏｌ／／ｌ）;Ｖ：高锰酸钾浓度标定时,高锰酸钾溶液消耗量（ｍｌ）;Ｋ：高锰酸钾溶液校正系数;Ｖ０：空白试验中高锰酸钾溶液消耗量（ｍ...     

光度法测定硫酸盐方法的改进

①向水样及标液中加２ｍｌ２５ｍｏｌ／Ｌ的盐酸溶液;②加热煮沸时间延长至１０ｍｉｎ;③用两层慢速定性滤纸过滤。改进后的硫酸盐测定：①空白值降至００１８～００２５,方法检测限为０４ｍｇ／Ｌ,低于原方法的检测限;②与原方法作对比标准曲线,经回归直线...     

测定水中挥发酚的测量不确定度评定

分析了采用预蒸馏的4-氨基安替比林萃取光度法,测定水中挥发酚过程中产生测量不确定度的主要来源．通过实例介绍了配制标准溶液、标准曲线拟合、重复性测量、分光光度计仪器等引入的各不确定度分量的量化计算方法．经合成计算出测定水中挥发酚的扩展不确定度为0．001mg／L．测量结果表示为（0．011±0．001）mg／L（=2）．     

Monitoring of Daily Integrated Exposure of Outdoor Workers to Respirable Particulate Matter in an Urban Region of India

It is more and more recognised that an estimation of the exposure of the population to air pollutants is more relevant than the ambient air quality, since it gives a better indication of health risk. Outdoor workers in an urban region are generally of low income status and are exposed to higher levels of both indoor and outdoor air pollution. Hence respondents from this population subgroup have been selected for this study. Outdoor workers are divided into two categories, viz. traffic constables and casual outdoor workers like watchmen, roadside shopkeepers etc. Most of the respondents are from the lower income group. Each respondent is monitored for a continuous 48-hour period. The sampling frequency is once a week.The study region is situated in the north-west part of the Greater Mumbai Municipal Corporation. It can be classified as industrial cum residential area. The daily integrated exposure of the outdoor workers consists of two major micro-environments, viz. occupational and indoor residential.A personal air sampler was used along with a cyclone to measure levels of Respirable Particulate Matter (RPM). The cyclone has a 50% removal efficiency for particle diameter of 5 m. Paired samples of PM10 (ambient) and RPM (personal) were collected to establish the correlation between them. The average 24-hour integrated exposure to RPM was 322 g/m3 and exceeded the corresponding PM10 level observed at the nearest Ambient Air Quality Monitoring Station by a factor of 2.25. The 90% confidence interval for this exposure is 283–368 g/m3. This study clearly demonstrates that the daily integrated exposure and therefore the health risk of outdoor workers in an urban area is significantly more serious than that indicated by ambient air quality data.     

Reduction of SO2 Emissions by Ammonia Gas During Staged Combustion

To reduce SO2 emissions, ammonia gas was injected into a coal-fired fluidized-bed combustor under staged commbustion condition. The combustor was 2 m high with a 30 cm static bed height and a freeboard height of 170 cm. The ammonia gas was injected at 52 cm and 65 cm above the distributor, which had a temperature of ca. 700 °C, by an uncooled stainless-steel tube injector. The experiments investigated the effects of ammonia gas injection on sulphur dioxide emissions at staged conditions, varying the: (i) excess air level, (ii) secondary air ratio, (iii) fluidizing velocity, (iv) ammonia injection position, and (v) the ammonia : sulphur dioxide molar ratio.A maximum reduction of 66% in SO2 emissions was found at 40% excess air, 65 : 35 staging, 1.5 m/s fluidizing velocity, 65 cm injection height, and an NH3 : SO2 molar ratio of 1.2. The onset of SO2 reduction occurred at an NH3 : SO2 ratio of 0.5. The fluidizing velocity, excess air, level of staging, and ammonia injection height all have a significant influence on SO2 reduction.It is difficult to determine how the SO2 reduction varies with the operating conditions when ammonia is injected in the high temperature zone of the combustor. As sulphur oxides-ammonia reactions are low temperature reactions, the findings confirm the occurrence of reactions above the freeboard or near the exit to the cyclone.     

Sulfuric acid at workplaces--applicability of the new Indicative Occupational Exposure Limit Value (IOELV) to thoracic particles

Until 2009, the limit values for airborne sulfuric acid in Europe were based on the inhalable particle fraction (e.g. MAK (Maximum allowed concentration at workplace) value 0.1 mg m(-3) as the inhalable fraction). With the publication of the Commission Directive 2009/161/EU, an Indicative Occupational Exposure Limit Value (IOELV) of 0.05 mg m(-3) for sulfuric acid aerosols was based for the first time on the thoracic particle fraction. To permit a comparison of the measured values for the inhalable fraction with those of the thoracic fraction and to quantify the thoracic fraction, a cyclone was fabricated out of sulfuric-acid-resistant stainless steel that achieves suitable collection characteristics (PM(10)) at a flow rate of 5.34 L min(-1). 49 measurements were carried out in parallel in 21 companies. At concentrations well below the IOELV, there is little difference between the thoracic and inhalable particle concentrations. At higher concentrations (>0.1 mg m(-3) inhalable aerosol), larger droplets have a marked effect on the measured values and the thoracic fraction accounts for only 32.1 ± 12.5% of the inhalable fraction. The EU's IOELV and the proposal of the MAK Commission therefore provide a comparable level of protection. In the transposition of the IOELV into national law, an air limit of 0.1 mg m(-3) could therefore be implemented for the inhalable fraction.     

Combined Non-Catalytic Reduction of NOx and SO2 by Ammonia Liquor during Staged Fluidized-Bed Combustion

Emissions of NOx and SO2 were monitored in the presence of ammonia liquor in a 0.09 m2 and 2 m high stainless-steel fluidized-bed combustor. Experiments were carried out at 2 m/s fluidizing velocity, 40% excess air, and 870 °C bed temperature. Ammonia liquor with 7% ammonia by weight was injected into the freeboard of the combustor 52 cm above the distributor through a water-cooled injector. A 65 : 34 primary/secondary air ratio was maintained throughout the investigation. Approximately 70% of NO and 20% of SO2 was reduced at an NH3/NO molar ratio of 2 : 1, respectively. However, a higher reduction in SO2 emissions (62%) was achieved at a very high NH3/NO molar ratio of 7 : 1. These experiments showed that ammonia addition did have a significant effect in SO2 reduction if injected in an excess amount. The injection of ammonia liquor combined with staged combustion was found to be very effective in reducing NOx emissions. A reduction of about 50% was achieved at an NH3/NO molar ratio of 0.6 : 1 which is also coupled with a very low level of ammonia in the flue.     

流动注射分析法在挥发酚测定中的不确定因素分析

从基线波动、气泡干扰、相分离膜干扰及试剂和标准的干扰等4个方面,总结了流动注射分析法在挥发酚测定中的不确定因素,并提出了有效的改进建议。     

Size-selective sampling of particulates using a physiologic sampling pump

Recent laboratory research indicates physiologic sampling of gas and vapor may provide more representative estimates of personal exposures than traditional methods. Modifications to the physiologic sampling pump (PSP) used in that research are described which extend its usefulness to size-selective sampling of particulates. PSPs used in previous research varied motor speed to keep sampling proportional to the subject's inhalation. This caused airflow and particle velocities through the collection device to continually change making those pumps unsuitable for sampling particulates. The modified implementation of the PSP pulls a constant airflow into and through a cyclone, then uses valves to either direct the airflow through, or divert the airflow around, the sampling filter. By using physiologic inputs to regulate the fraction of each second that air flows through the sampling filter, samples may be collected in proportion to inhalation rate. To evaluate the performance of a functional prototype 5 different sizes of monodisperse aerosols of ammonium fluorescein were generated by a vibrating orifice aerosol generator and introduced into a calm air chamber. To simulate different inhalation rates the valves of the PSP were energized using 9 different duty cycles. Efficiency curves are presented and compared to a standard respirable convention by bias mapping. The performance of the modified cyclone used in the PSP sampling head compared favorably with a commercially available cyclone of the same model, operating at a constant airflow (± 10% over almost all the size distributions of concern). The new method makes physiologic sampling of the respirable fraction of particulates feasible.     

Air Quality and Monitoring Strategy in the Helsinki Metropolitan Area, Finland

The Helsinki Metropolitan Area Council (YTV) is responsible for air quality monitoring in the Helsinki area. Air quality has been monitored periodically since the late 1950s. An automatic SO2 monitoring network was constructed in 1975 and TSP measurements were added in 1978. Since then the network has been expanded and currently five automatic multicomponent stations form the basis of the network monitoring SO2, NO, NO2, CO, PM10 and O3 concentrations. Manual TSP and PM10 measurements are also conducted. Mobile monitoring units are also being used as well as special measurement campaigns. The effects of air pollution on nature are studied in bioindicator monitoring. An air quality index is used in order to inform the public of the current air quality situation. Changes in air quality are reflected in monitoring strategy. SO2 concentrations have decreased in the past two decades. Annual averages in 1995 were at or below 5 µg/m3. Traffic is the major source for pollutants even though catalytic converters have lowered traffic emissions somewhat. The highest annual average NO2 concentration at an urban site was 49 µg/m3 in 1995, and there has been no clear change in NO2 levels. There has been a decreasing trend in CO concentrations. Maximum annual TSP and PM10 averages in 1995 were 92 and 32 µg/m3, respectively. The highest average lead concentration was 0.01 µg/m3. Elevated concentrations are experienced from time to time. During the spring daily TSP and PM10 concentrations can go up to around 300 and 150 µg/m3, respectively. This is caused by resuspension mainly due to street sanding. Also a major winter NO2 episode occurred in December 1995. The highest hourly NO2 concentrations reached 400 µg/m3.     

便携式GC/MS热脱附法直接测定环境空气中挥发性有机物

采用便携式气相色谱/质谱联用热脱附法直接测定环境空气中的挥发性有机物,优化了试验条件。方法在5×10-9~100×10-9范围内线性良好,39种化合物的检出限为1.1μg/m3~19μg/m3,标准气体平行测定的RSD≤11.0%,回收率在80%~120%之间。     

Indirect prediction of surface ozone concentration by plant growth responses in East Asia using mini-open top chambers

We developed small and mobile open top chambers (mini-OTC) measuring 0.6 m (W)?×?0.6 m (D)?×?1.2 m (H) with an air duct of 0.6 m (W)?×?0.23 m (D)?×?1.2 m (H). The air duct can be filled with activated charcoal to blow charcoal filtered air (CF) into the chamber, as opposed to non-filtered ambient air (NF). Ozone sensitive radish Raphanus sativus cv. Red Chime and rosette pakchoi Brassica campestris var. rosularis cv. ATU171 were exposed to NF and CF in mini-OTCs at different locations in East Asia. A total of 29 exposure experiments were conducted at nine locations, Shanghai, China, Ha Noi, Vietnam, Lampang, Phitsanulok and Pathumtani, Thailand, and Hiratsuka, Kisai, Abiko and Akagi, Japan. Although no significant relationships between the mean concentrations of ambient O₃ during the experimental period and the growth responses were observed for either species, multiple linear regression analysis suggested a good relationship between the biomass responses in each species and the O₃ concentration, temperature, and relative humidity. The cumulative daily mean O₃ (ppb/day) could be indirectly predicted by NF/CF based on the dry weight ratio of biomass, mean air temperature, and relative air humidity.     

离子色谱法测定空气中氟化氢氯化氢和硫酸

以多孔玻板吸收管采样,采用离子色谱法同时测定作业场所空气中的氟化氢、氯化氢和硫酸,采样效率>92%。氟化氢在0 mg/L～2.00 mg/L、氯化氢在0 mg/L～2.50 mg/L、硫酸在0 mg/L～4.00 mg/L范围内线性良好,检出限分别为0.003 mg/m3、0.02 mg/m3、0.023 mg/m3(按采样体积60 L计),标准溶液平行测定的RSD≤8.0%,两个质量浓度水平加标的平均回收率为92.6%～106%。