Atmospheric particulate matter(PM2.5) seriously influences air quality. It is considered one of the main environmental triggers for lung and heart diseases. Air pollutants can be adsorbed by forest. In this study we i...Atmospheric particulate matter(PM2.5) seriously influences air quality. It is considered one of the main environmental triggers for lung and heart diseases. Air pollutants can be adsorbed by forest. In this study we investigated the effect of forest cover on urban PM2.5 concentrations in 12 cities in Heilongjiang Province,China. The forest cover in each city was constant throughout the study period. The average daily concentration of PM2.5 in 12 cities was below 75 lg/m^3 during the non-heating period but exceeded this level during heating period. Furthermore, there were more moderate pollution days in six cities. This indicated that forests had the ability to reduce the concentration of PM2.5 but the main cause of air pollution was excessive human interference and artificial heating in winter. We classified the 12 cities according to the average PM2.5 concentrations. The relationship between PM2.5 concentrations and forest cover was obtained by integrating forest cover, land area,heated areas and number of vehicles in cities. Finally,considering the complexity of PM2.5 formation and based on the theory of random forestry, we selected six cities and analyzed their meteorological and air pollutant data. The main factors affecting PM2.5 concentrations were PM10,NO_2, CO and SO_2 in air pollutants while meteorological factors were secondary.展开更多
The dosage of environmental radon progeny is typically estimated according to the environmental radon exposure and the recommended radon-progeny equilibrium factor, F. To investigate the relationship between PM2.5 and...The dosage of environmental radon progeny is typically estimated according to the environmental radon exposure and the recommended radon-progeny equilibrium factor, F. To investigate the relationship between PM2.5 and the radon-progeny equilibrium factor, cigarettes are used to simulate the haze–fog in a multi-functional radon chamber to achieve a stable radon concentration environment. A radon detector and a portable laser aerosol spectrometer are used to obtain the values for C_(mean) PM2.5,C_(Rn), and C_p. The results show that the mean values of F conform with the typical value recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation and are within the reasonable range of0.1–0.9. In this study, a positive correlation is observed between the F values and PM2.5 concentrations.展开更多
Since 1991, air pollution has gained special attention in Taiwan after a petrochemical complex was constructed in Mailiao Township, Yunlin County. We explored the association between the magnitude of PM2.5 and meteoro...Since 1991, air pollution has gained special attention in Taiwan after a petrochemical complex was constructed in Mailiao Township, Yunlin County. We explored the association between the magnitude of PM2.5 and meteorological factors during 2012-2016. Our findings revealed that 1) mean PM2.5 levels gradually decreased from 30.70 μg/m3 in 2013 to 25.36 μg/m3 in 2016;2) wind speed is the main determinant of air quality—air quality significantly improved when it was faster than 4 m/sec;and 3) wind direction is another determinant of air quality—when the wind direction was southerly, air quality improved. Elevated PM2.5 levels were defined as those hourly levels higher than the third quartile (36 μg/m3). The significantly negative predictive factors for elevated PM2.5 levels were the summer or autumn seasons, rainfall, increased wind speed, and wind direction from 150° to 230° from the north. The significantly positive predictive factors for elevated PM2.5 levels were working hours from 6 a.m. to 2 p.m., a temperature between 11°C and 25°C, relative humidity between 40% and 68%, and wind direction (e.g., northerly wind, northeasterly wind, and easterly wind). The predictive formula is attached in the Appendix. Therefore, people should protect themselves on these high-risk days.展开更多
鉴于烟台市本地化源成分谱研究缺乏的现状,以及颗粒物精细化来源解析及环境管理的需求,采用NK-ZXF颗粒物再悬浮采样器,对6家烟台市典型工业下载灰源样品进行再悬浮采样,构建6类〔燃煤电厂、供热锅炉、生物质锅炉、钢铁(烧结)行业、玻璃...鉴于烟台市本地化源成分谱研究缺乏的现状,以及颗粒物精细化来源解析及环境管理的需求,采用NK-ZXF颗粒物再悬浮采样器,对6家烟台市典型工业下载灰源样品进行再悬浮采样,构建6类〔燃煤电厂、供热锅炉、生物质锅炉、钢铁(烧结)行业、玻璃行业和垃圾处理行业〕PM2.5源成分谱,并对PM2.5源成分谱特征及其排放颗粒物携带重金属特征进行评估.结果表明:①燃煤电厂PM2.5源成分谱的标识组分包括Si、Cl^-和SO4^2-,其质量分数分别为15.2%、9.3%和7.8%;与燃煤电厂相比,供热锅炉排放的PM2.5中w(OC)偏高、w(SO4^2-)偏低;生物质锅炉排放的主要组分有K、Cl^-和OC等,其质量分数分别为7.4%、13.3%和8.6%;钢铁(烧结)行业PM2.5源成分谱中w(Ca)、w(Fe)和w(Cl^-)较高;SO4^2-和Ca为玻璃行业PM2.5源成分谱的主要组分,其质量分数分别为20.6%、8.2%;垃圾处理行业重金属质量分数最高,其主要组分为Cl^-和SO4^2-.②CD (coefficient of divergence,分歧系数)计算结果表明,各源成分谱有一定相异性(CD范围为0.53~0.70),其中生物质锅炉与垃圾处理行业PM2.5源成分谱差异(CD为0.70)最大.③各典型工业排放PM2.5所携带重金属特征显示,垃圾处理行业排放PM2.5中的重金属质量分数(2.3%)最高,燃煤电厂、供热锅炉、生物质锅炉和玻璃行业排放的重金属中Cr、Ni和Cu相对质量分数较高,钢铁行业和垃圾处理行业排放的重金属中Pb相对质量分数较高.研究显示,所构建的烟台市各典型工业排放PM2.5源成分谱特征鲜明,能够反映各行业PM2.5排放特征.展开更多
The pollution of particulate matter less than 2.5μm （PM2.5） is a serious environmental problem in Beijing. The annual average concentration of PM2.5 in 2001 from seasonal monitor results was more than 6 times that ...The pollution of particulate matter less than 2.5μm （PM2.5） is a serious environmental problem in Beijing. The annual average concentration of PM2.5 in 2001 from seasonal monitor results was more than 6 times that of the U,S, national ambient air quality standards proposed by U.S. EPA. The major contributors to mass of PM2.5 were organics, crustal elements and sulfate. The chemical composition of PM2.5 varied largely with season, but was similar at different monitor stations in the same season. The fine particles （PM2.5） cause atmospheric visibility deterioration through light extinction, The mass concentrations of PM2.5 were anti-correlated to the visibility, the best fits between atmospheric visibility and the mass concentrations of PM2.5 were somehow different： power in spring, exponential in summer, logarithmic in autumn, power or exponential in winter. As in each season the meteorological parameters such as air temperature and relative humidity change from day to day, probably the reason of above correlations between PM2.5 and visibility obtained at different seasons come from the differences in chemical compositions of PM2.5.展开更多
The objective of this study was to identify the impact of the coke handling and storage system on the emission of PM10 particulate material.The methodology was based on AP-42 emission factors from U.S.EPA(United State...The objective of this study was to identify the impact of the coke handling and storage system on the emission of PM10 particulate material.The methodology was based on AP-42 emission factors from U.S.EPA(United States Environmental Protection Agency)for the calculation of PM10 emissions from operations in the handling and storage of petroleum coke in an oil refinery in the northeastern of Brazil.The knowledge of the emission potential of each operation of the coke handling and storage system allows the adoption of more effective control measures,contributing to the effective reduction of PM10 emissions in this system.To complement the environmental impact assessment of each configuration,an air quality modelling was performed using the atmospheric dispersion software.The comparison performed in this study enables authors to conclude,even for a totally mechanic system,that adopts control measures,PM10 emissions are low when confronted with the remaining sources of an oil refinery.By analyzing emissions from automated systems operation(scenario 1),it can be observed that the source with higher emission potential is the stockpile,which represents 60%of the system’s emission.Transfer and transport operations by conveyor belts together correspond to 40%of emissions.Even though transfer operations also represent a significant part(27%),they are not clustered in a unique point,making these emissions abatement difficult.The same is valid for transport using conveyor belts.Emissions from the piles are really the most significant.For this reason,this work concentrated efforts in the storage area,the ones that motivate the majority of studies relating to abatement technologies.展开更多
Particle emission during manufacturing processes, whether chemical, physical or mechanical can represent a serious danger for environment and for occupational safety. Especially machining processes, particle emission ...Particle emission during manufacturing processes, whether chemical, physical or mechanical can represent a serious danger for environment and for occupational safety. Especially machining processes, particle emission could have an important impact on shop floor air quality and might jeopardise workers’ health. It is therefore important to find ways of reducing the particle emission at the source of manufacturing processes. To do so, there is a need to know the size, the quantity and the distribution of particles produced by processes currently used in industry. In this study, investigations are done to compare the particle emission (PM2.5) when polishing two granites (black and white). The black granite contained low Si concentration (about 10% Si) and the white granite contained high Si concentration (about 50% Si). Particle emission was monitored using the DustTrak II equipment with 2.5 μm impactor. The particle grain size was evaluated using X-ray diffraction techniques. Machining conditions leading to the generation of finer particles were identified.展开更多
基金supported by the Natural Science Foundation of Heilongjiang Province,China(Grant No.G2016001)
文摘Atmospheric particulate matter(PM2.5) seriously influences air quality. It is considered one of the main environmental triggers for lung and heart diseases. Air pollutants can be adsorbed by forest. In this study we investigated the effect of forest cover on urban PM2.5 concentrations in 12 cities in Heilongjiang Province,China. The forest cover in each city was constant throughout the study period. The average daily concentration of PM2.5 in 12 cities was below 75 lg/m^3 during the non-heating period but exceeded this level during heating period. Furthermore, there were more moderate pollution days in six cities. This indicated that forests had the ability to reduce the concentration of PM2.5 but the main cause of air pollution was excessive human interference and artificial heating in winter. We classified the 12 cities according to the average PM2.5 concentrations. The relationship between PM2.5 concentrations and forest cover was obtained by integrating forest cover, land area,heated areas and number of vehicles in cities. Finally,considering the complexity of PM2.5 formation and based on the theory of random forestry, we selected six cities and analyzed their meteorological and air pollutant data. The main factors affecting PM2.5 concentrations were PM10,NO_2, CO and SO_2 in air pollutants while meteorological factors were secondary.
基金supported by the National Natural Science Foundation of China(No.11565002)the Jiang Xi Young Science Foundation Project(No.GJJ150558)Open Funds of Engineering Research Center of Nuclear Technology Application of Ministry of Education(No.HJSJYB2017-2)
文摘The dosage of environmental radon progeny is typically estimated according to the environmental radon exposure and the recommended radon-progeny equilibrium factor, F. To investigate the relationship between PM2.5 and the radon-progeny equilibrium factor, cigarettes are used to simulate the haze–fog in a multi-functional radon chamber to achieve a stable radon concentration environment. A radon detector and a portable laser aerosol spectrometer are used to obtain the values for C_(mean) PM2.5,C_(Rn), and C_p. The results show that the mean values of F conform with the typical value recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation and are within the reasonable range of0.1–0.9. In this study, a positive correlation is observed between the F values and PM2.5 concentrations.
文摘Since 1991, air pollution has gained special attention in Taiwan after a petrochemical complex was constructed in Mailiao Township, Yunlin County. We explored the association between the magnitude of PM2.5 and meteorological factors during 2012-2016. Our findings revealed that 1) mean PM2.5 levels gradually decreased from 30.70 μg/m3 in 2013 to 25.36 μg/m3 in 2016;2) wind speed is the main determinant of air quality—air quality significantly improved when it was faster than 4 m/sec;and 3) wind direction is another determinant of air quality—when the wind direction was southerly, air quality improved. Elevated PM2.5 levels were defined as those hourly levels higher than the third quartile (36 μg/m3). The significantly negative predictive factors for elevated PM2.5 levels were the summer or autumn seasons, rainfall, increased wind speed, and wind direction from 150° to 230° from the north. The significantly positive predictive factors for elevated PM2.5 levels were working hours from 6 a.m. to 2 p.m., a temperature between 11°C and 25°C, relative humidity between 40% and 68%, and wind direction (e.g., northerly wind, northeasterly wind, and easterly wind). The predictive formula is attached in the Appendix. Therefore, people should protect themselves on these high-risk days.
文摘鉴于烟台市本地化源成分谱研究缺乏的现状,以及颗粒物精细化来源解析及环境管理的需求,采用NK-ZXF颗粒物再悬浮采样器,对6家烟台市典型工业下载灰源样品进行再悬浮采样,构建6类〔燃煤电厂、供热锅炉、生物质锅炉、钢铁(烧结)行业、玻璃行业和垃圾处理行业〕PM2.5源成分谱,并对PM2.5源成分谱特征及其排放颗粒物携带重金属特征进行评估.结果表明:①燃煤电厂PM2.5源成分谱的标识组分包括Si、Cl^-和SO4^2-,其质量分数分别为15.2%、9.3%和7.8%;与燃煤电厂相比,供热锅炉排放的PM2.5中w(OC)偏高、w(SO4^2-)偏低;生物质锅炉排放的主要组分有K、Cl^-和OC等,其质量分数分别为7.4%、13.3%和8.6%;钢铁(烧结)行业PM2.5源成分谱中w(Ca)、w(Fe)和w(Cl^-)较高;SO4^2-和Ca为玻璃行业PM2.5源成分谱的主要组分,其质量分数分别为20.6%、8.2%;垃圾处理行业重金属质量分数最高,其主要组分为Cl^-和SO4^2-.②CD (coefficient of divergence,分歧系数)计算结果表明,各源成分谱有一定相异性(CD范围为0.53~0.70),其中生物质锅炉与垃圾处理行业PM2.5源成分谱差异(CD为0.70)最大.③各典型工业排放PM2.5所携带重金属特征显示,垃圾处理行业排放PM2.5中的重金属质量分数(2.3%)最高,燃煤电厂、供热锅炉、生物质锅炉和玻璃行业排放的重金属中Cr、Ni和Cu相对质量分数较高,钢铁行业和垃圾处理行业排放的重金属中Pb相对质量分数较高.研究显示,所构建的烟台市各典型工业排放PM2.5源成分谱特征鲜明,能够反映各行业PM2.5排放特征.
基金The General Project of the Beijing Municipal Natural Science Foundation (No. 8012009) and the Key Project of the BeijingMunicipal Sciences & Technology Commission (No. H020620190091-H020620250230)
文摘The pollution of particulate matter less than 2.5μm （PM2.5） is a serious environmental problem in Beijing. The annual average concentration of PM2.5 in 2001 from seasonal monitor results was more than 6 times that of the U,S, national ambient air quality standards proposed by U.S. EPA. The major contributors to mass of PM2.5 were organics, crustal elements and sulfate. The chemical composition of PM2.5 varied largely with season, but was similar at different monitor stations in the same season. The fine particles （PM2.5） cause atmospheric visibility deterioration through light extinction, The mass concentrations of PM2.5 were anti-correlated to the visibility, the best fits between atmospheric visibility and the mass concentrations of PM2.5 were somehow different： power in spring, exponential in summer, logarithmic in autumn, power or exponential in winter. As in each season the meteorological parameters such as air temperature and relative humidity change from day to day, probably the reason of above correlations between PM2.5 and visibility obtained at different seasons come from the differences in chemical compositions of PM2.5.
文摘The objective of this study was to identify the impact of the coke handling and storage system on the emission of PM10 particulate material.The methodology was based on AP-42 emission factors from U.S.EPA(United States Environmental Protection Agency)for the calculation of PM10 emissions from operations in the handling and storage of petroleum coke in an oil refinery in the northeastern of Brazil.The knowledge of the emission potential of each operation of the coke handling and storage system allows the adoption of more effective control measures,contributing to the effective reduction of PM10 emissions in this system.To complement the environmental impact assessment of each configuration,an air quality modelling was performed using the atmospheric dispersion software.The comparison performed in this study enables authors to conclude,even for a totally mechanic system,that adopts control measures,PM10 emissions are low when confronted with the remaining sources of an oil refinery.By analyzing emissions from automated systems operation(scenario 1),it can be observed that the source with higher emission potential is the stockpile,which represents 60%of the system’s emission.Transfer and transport operations by conveyor belts together correspond to 40%of emissions.Even though transfer operations also represent a significant part(27%),they are not clustered in a unique point,making these emissions abatement difficult.The same is valid for transport using conveyor belts.Emissions from the piles are really the most significant.For this reason,this work concentrated efforts in the storage area,the ones that motivate the majority of studies relating to abatement technologies.
文摘Particle emission during manufacturing processes, whether chemical, physical or mechanical can represent a serious danger for environment and for occupational safety. Especially machining processes, particle emission could have an important impact on shop floor air quality and might jeopardise workers’ health. It is therefore important to find ways of reducing the particle emission at the source of manufacturing processes. To do so, there is a need to know the size, the quantity and the distribution of particles produced by processes currently used in industry. In this study, investigations are done to compare the particle emission (PM2.5) when polishing two granites (black and white). The black granite contained low Si concentration (about 10% Si) and the white granite contained high Si concentration (about 50% Si). Particle emission was monitored using the DustTrak II equipment with 2.5 μm impactor. The particle grain size was evaluated using X-ray diffraction techniques. Machining conditions leading to the generation of finer particles were identified.
