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In recent years, the Ministry of Ecology and Environment and the Beijing Municipal Government have continuously strengthened the control indicators of dustfall. In order to grasp the characteristics and sources of ion deposition in dustfall, the filtration method and ion chromatography were used to determine the dustfall and ion deposition during winter and spring in the core area of Beijing, and the PMF model was carried out to analyze the sources of ion deposition. The results indicated:â the average values of ion deposition and its proportion in dustfall were 0.87 t·(km2·30 d)-1 and 14.2%, respectively. The dustfall and ion deposition on working days were 1.3 times and 0.7 times that on rest days, respectively. â¡ The coefficient of determination in the linear equations between ion deposition and precipitation, relative humidity, temperature, and average wind speed were 0.54, 0.16, 0.15, and 0.02, respectively. In addition, the coefficient of determination in the linear equations between ion deposition and PM2.5 concentration and dustfall were 0.26 and 0.17, respectively. Therefore, controlling the concentration of PM2.5 was crucial to treating ion deposition. ⢠Anions and cations accounted for 61.6% and 38.4%, respectively, in the ion deposition, and SO42-, NO3-, and NH4+ accounted for 60.6% in total. The ratio of anion and cation charge deposition was 0.70, and the dustfall was alkaline. The ρ(NO3-)/ρ(SO42-) in the ion deposition was 0.66, which was higher than that of 15 years ago. ⣠The contribution rates of secondary sources, fugitive dust sources, combustion sources, snow-melting agent sources, and other sources were 51.7%, 17.7%, 13.5%, 13.5%, and 3.6%, respectively.
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Vapor processing device is a device that can control the headspace pressure in the underground storage tanks and recover the vapor. By analyzing the chemical composition of volatile organic compounds (VOCs) at the inlet and outlet of the vapor processing device, the ozone formation potential (OFP) and secondary organic aerosol formation potential (SOAP) were estimated by maximum incremental reaction (MIR) and fractional aerosol coefficients (FAC), and the secondary pollution formation contribution of VOCs were quantitatively evaluated. The results showed that:â the ρ(total volatile organic compounds, TVOC) at the inlet and outlet of the vapor processing device were 436-706 g·m-3 and 4.98-10.04 g·m-3, respectively. Alkanes (72%±4%), oxygenated organics (14%±2%), and olefins (11%±5%) were the dominant components of VOCs emissions. There were little differences in VOCs emissions from the different vapor processing devices; the key species were i-pentane (approximately 25%), followed by n-butane, i-butane, and n-pentane. â¡ The ozone source reactivity (SR) of VOCs emissions from the outlet of the vapor processing device was 2.6-3.3 g·g-1, and the OFP was 3.5-25.6 g·m-3. Olefins contributed the most (43%-69%), followed by alkanes (20%-35%) and oxygenated organics (10%-22%). Butene, cis-2-butene, trans-2-butene, i-pentane, and propionaldehyde were the species that highly contributed to OFP. ⢠Aromatics in VOCs emissions contributed the most to SOAP (80%-92%), and the main active species were toluene, 1, 2, 4-trimethylbenzene, 1, 3, 5-trimethylbenzene, and p-diethylbenzene. The research showed that different VOCs species emitted by the vapor processing device contributed obvious differences to the secondary atmospheric pollution, and butene species and aromatics such as toluene were the focus of VOCs emission control of vehicle gasoline and vapor processing device.
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Soil wind erosion dust is one of the primary sources of fine particulate matter (PM2.5). Compared with the fugitive dust emission inventory of typical domestic provinces and cities, we found that the maximum among the contribution rates of soil wind erosion dust to the local total fugitive dust PM2.5 emission inventory was about 4 orders of magnitude higher than the minimum. This study provided a wind erosion equation and a determination method of parameter values. The remote sensing interpretation, China soil dataset, and meteorological data of each district in Beijing were used to achieve the spatial distribution of the vegetation coverage factor (V), soil erodibility index (I), and climatic factors (C) in the plain area of Beijing. This study also estimated the emission factor of soil wind erosion dust and its spatial distribution. The main conclusions are as follows: â Taking 2017 and Beijing city as an example, it was found that the climatic factor (C) was underestimated to different extents by domestic scholars, and PM2.5 emission factors were overestimated or underestimated. â¡ V, I, and C showed apparent spatial differences and the average values of them were 0.63±0.09, 188±73, and 0.029±0.009, respectively. The maximum values of V, I, and C were 1.5, 2.1, and 4.5 times the minimum among all districts, respectively. ⢠The PM2.5 emission factor of soil wind erosion dust in Beijing showed a high spatial distribution in the northwest and southeast. The average emission factor of the city was (0.0018±0.0008) t·(hm2·a)-1, which is 0.54 times the highest emission factor (Xicheng District) and 3.12 times the lowest (Pinggu District). The area proportions of standardized emission factors with higher intensity (0.6 to 0.8] and high intensity (0.8 to 1.0] was 0.72% and 0.04%, respectively.
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Chinese emission standard of air pollutants for bulk gasoline terminals (GB 20950-2007) stipulate standards for vapor emissions during gasoline storage and receiving in bulk gasoline terminals. However, the standards are not applicable to crude oil, aviation kerosene, naphtha, and other kinds of oil. We assess emission standards or directives for vapor processing equipment in terminals in the United States (US) and European Union (EU), and analyze the emission status of vapor processing equipment in three typical cities in China. We further propose revisions to GB 20950-2007. We made the following observations. â US and EU standards include scope not only for gasoline, but also crude oil and other organic liquids. â¡ The emission limits of non-methane hydrocarbons defined in GB 20950-2007 are i) 0.5, 1.8, and 8.9 times those defined in Subpart XX, Subpart R, and Subpart Y in the US federal regulations, ii) 1.8 and 3.1 times those defined in Rule 462 and Rule 1142 in southern California law, and iii) 0.7 and 500 times those defined in EU and German directives, respectively. The vapor leakage limit for general areas of China is 0.5 times that defined in Subpart XX of the US standards, whereas the limits for some other specific areas of China, are 0.7 and 2.0 times those defined by Rule 462 and Rule 1142 in southern California law. ⢠The numerical range of P5th-P95th of NMHC emissions from the inlet and outlet of vapor processing equipment in three typical cities of China were 115-811 g·m-3 and 0.1-20.0 g·m-3, respectively. The proportion of NMHC emission concentrations less than or equal to 10 g·m-3 at the outlet of vapor processing equipment was>85%. We suggest that the scope of application of GB 20950-2007 should be extended to crude oil, gasoline (including ethanol gasoline), aviation kerosene, and naphtha. The emission concentration limit of NMHC from vapor processing equipment should be tighten from 25 g·m-3 to 20 g·m-3, with a emission limit of 10 g·m-3 added for particular cases.
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Wind erosion dust suppressant is an effective measure for controlling wind erosion dust. This study used the Portable In-Situ Wind Erosion Laboratory (PI-SWERL) to evaluate the efficiency of domestic and foreign dust suppressants and to compare their control efficiency of PM2.5 in terms of spraying methods, dilution factors, and wind speed. The following results were noted.â According to the recommended dilution factor, G and Enviroseal (ES) dust suppressant solutions were treated and tested, respectively. The control efficiency of particulate matter with diameters less than 2.5 µm (PM2.5) corresponding to the droplet spraying method was better than the atomized spraying method; the G dust suppressant efficiency, at 99.5%, was better than ES and water, at 94.0% and 77.5%, respectively, at 17.2 m·s-1, which is equivalent to grade 8 wind. â¡ The G dust suppressant with dilution factors of 50, 100, 150, 200, and 400 times was tested. The dust suppression efficiency at a wind speed of 17.2 m·s-1 was 99.7%, 99.5%, 99.7%, 98.1%, and 95.9%, respectively. The best cost-effective dilution factor of G dust suppressant was 150 times. The efficiency of dust suppressants increased when the wind speed increased between 13.1 m·s-1 and 17.2 m·s-1. ⢠The method of using PI-SWERL to test the efficiency of wind erosion dust suppressant can quantify the suppression efficiency of dust suppressant on PM2.5. It is recommended to conduct dust suppression during effective periods and to practice environmentally friendly methods of wind erosion dust suppression.
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Concrete batching plants are a typical source of fugitive dust in Beijing. In this study, two concrete batching plants in Beijing were used to test wind erosion of dust with a Portable In-suit Wind Erosion Laboratory (PI-SWERL) designed by the Desert Research Institute (DRI). Sand and aggregate storage piles and paved roads in concrete batching plants were tested to determine the emission characteristics of wind eroded dust. Combining the frequencies of disturbance of storage piles and paved road surface with local meteorological data, localized wind erosion dust emission factors of PM2.5 were established. Results demonstrate that:â There are small differences in daily average emission factors for PM2.5 between the aggregate warehouse entrance area, concrete loading area, social road import area, and concrete batching plant entrance area, with these being 0.45, 0.41, 0.31, and 0.30 kg·(hm2·d)-1, respectively. â¡Daily average emission factors for PM2.5 of coarse stone, fine stone, coarse sand, and fine sand storage piles are 0.10, 0.12, 0.26, and 2.02 kg·(hm2·d)-1, respectively. Emission factors of fine sand storage piles are 20.5, 16.8, and 7.7 times greater than those of coarse stone, fine stone, and coarse sand, respectively, and spring emission factors are 6.4, 3.4, and 1.3 times greater than those of summer, autumn, and winter, respectively. â¢Daily average emission factors for PM2.5 of storage piles and paved roads are 1.13 and 0.37 kg·(hm2·d)-1, respectively 3.9 and 1.3 times higher than the wind erosion factor from storage piles from AP-42 files (c11s12 concrete batching, 1995); the uncertainty range of the emission factor is 34%-92%. â£It is recommended to strengthen watering, sweeping, and cleaning of paved roads, and to ensure fully enclosed storage and use of spray water to reduce wind erosion of dust from storage piles, especially from fine sand piles.
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As a subcenter of the city of Beijing, Tongzhou District is faced with enormous pressure from the rapid growth of VOCs emissions from service stations. In this study, a set of bottom-up VOCs inventory estimation methods for service stations in Tongzhou District is established. Using local VOCs emission factors of service stations in Beijing, combined with gasoline and diesel sales from every service station, a high resolution VOCs emission inventory of service stations in Tongzhou District from 2015 to 2022 was established. The results showed the following. â An online monitoring system (OMS) based on unloading, refueling, and tank pressure vapor emission control measures can reduce the VOCs emission factor from 190 mg·L-1 to 115 mg·L-1, and when the percent onboard refueling vapor recovery system (ORVR) Penetration reaches to about 50%, the emission factors can be reduced to 131 mg·L-1 and 96 mg·L-1, respectively. The VOCs emission factor (13 mg·L-1) of diesel from the service station is 0.8% of the uncontrolled emission factor (1552 mg·L-1) of gasoline. â¡The amount of VOCs emissions from service stations in Tongzhou District was 97.8 t·a-1 in 2015, and the emissions of gasoline and diesel were 96.2 t·a-1 and 1.6 t·a-1, respectively, accounting for 98.4% and 1.6%. The emissions were mainly concentrated in the area surrounding the new Beijing Municipal Government site. â¢After implementation of the vapor recovery requirements of "Beijing's Clean Air Action Plan from 2013-2017," considering the increase in oil sales from 2017 to 2022, VOCs emissions of gasoline and diesel from service stations will decrease by 9% and 6%, respectively, compared to those of 2015 in Tongzhou District. Assuming that the OMS will also be installed at 28 (2000-5000) t·a-1 service stations by the end of 2022, VOCs emissions of service stations will be reduce by 13% compared to those of 2015. â£The measure of restricting the number of vehicles in operation by 50% can reduce VOCs emissions of service stations by (22±12)% every day during 2014 Asia-Pacific Economic Cooperation conference (APEC). â¤It is suggested to strengthen vapor recovery supervision on service stations in the area surrounding the new Beijing Municipal Government site, and in summer and refueling idle such as in noon.
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This study characterized the wind erosion dust emissions from topsoil of urban roadside-tree pool. The study area is the Xicheng District of Beijing and uses GIS to obtain the spatial distribution of various road mileages. A full bore investigation method was carried out to survey tree pool in the Zhanlanlu Subdistrict to obtain the activity level of tree pool in the Xicheng district. The portable in situ wind erosion laboratory (PI-SWERL) was used to determine the emission factors of PM2.5 from the wind erosion dust from tree pool and to estimate the PM2.5 emission inventory of tree pool in the Xicheng District in 2016. The results showed that:â The annual emission factors per unit area of PM2.5 from tree pool of freeways' frontage roads, major roads, minor roads, and alleys are 47.9, 7.9, 14.9, and 29.9 g·(m2·a)-1, respectively. The reduction rate of PM2.5 emission factors from tree pool by precipitation was about 30.3% in 2016. â¡The annual emission factors per unit mileage of PM2.5 from the tree pool of freeways' frontage roads, major roads, minor roads, branch roads, and alleys are 2.57, 2.33, 4.04, 7.31, and 5.44 kg·(km·a)-1, respectively, and the factors for branch roads are 1.3, 1.8, 2.8, and 3.1 times as much as those for alleys, minor roads, freeways' frontage roads, and major roads, respectively. Taking the emission factor for minor roads as an example, the winter emission factor is 1.3, 7.3, and 8.7 times greater than that in the spring, summer, and autumn, respectively. â¢PM2.5 emissions from the tree pool in the Xicheng District of Beijing are 1.60 t·a-1, and the uncertainty range of the emission inventory is -143%~184%. The emissions in winter are 0.68 t·a-1, which are 1.1, 1.42, and 5.1 times greater than that in the spring, summer, and fall, respectively. The emission values for freeways' frontage roads, major roads, minor roads, collectors, and alleys account for 5.6%, 8.7%, 23.2%, 4.1%, and 58.4% of the total emissions, respectively. It is recommended that the urban roadside-tree pool be covered to reduce wind erosion dust emissions with materials that do not affect the growth of trees as soon as possible.
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Poeira , Monitoramento Ambiental , Solo , Árvores , Vento , Poluentes Atmosféricos/análise , Pequim , Material Particulado/análiseRESUMO
Particulate matter (PM) is the primary air pollutant in Beijing, and its emission control is an important direction of air pollution prevention and control. Construction dust plays a significant role in the source of airborne particulate matter in Beijing. Due to population growth and economic development, the demand for residential and office space has been increasing which results in a high construction area in Beijing and dust pollution caused by construction activities. However, there are few studies focusing on fugitive dust emissions from construction sites and their contribution to air pollution in Beijing. Under this background, this paper established an estimation model of dust emission from construction sites, and used the localized emission factor to calculate the dust emission from 2000 to 2015 in Beijing, identified the emission characteristics and laws of construction dust emission and quantified the uncertainty range of the emissions. The WRF/CMAQ model system was used to simulate the contribution of dust pollution to quantify its influence on air quality. The results showed that the dust emission from construction sites in Beijing has been increasing, but the construction area is falling in recent years. However, the emission of PM is still high and needs to be paid enough attention. In the spatial distribution, the dust emissions in summer and autumn are larger than those in other seasons. As for spatial distribution, the construction dust is mainly concentrated in the urban function extension area and suburban area, which is related to the extension of population activities and the gradual development of urbanization. The contribution of construction dust to PM10 and PM2.5 concentration in the ambient air can reach 31.3 µg·m-3 and 9.6 µg·m-3, respectively. Through scenarios analysis, for further reduction of the emission from construction sites in 2030, more stricter standard for green construction and powerful supervision are needed.
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With the economic development and population growth in Beijing, there is a strong need for construction and housing, which leads to the increase of the construction areas. Meanwhile, as a local provided material, the production of concrete has been raised. In the process of concrete production by concrete batching, there are numerous particulates emitted, which have large effect on the atmospheric environment, however, systematic study about the tempo-spatial characteristics of pollutant emission from concrete batching is still rare. In this study, we estimated the emission of particulates from concrete batching from 1991 to 2012 using emission factor method, analyzed the tempo-spatial characteristics of pollutant emission, established the uncertainty range by adopting Monte-Carlo method, and predicted the future emission in 2020 based on the relative environmental and economical policies. The results showed that: (1) the emissions of particulates from concrete batching showed a trend of "first increase and then decrease", reaching the maximum in 2005, and then decreased due to stricter emission standard and enhanced environmental management. (2) according to spatial distribution, the emission of particulates from concrete batch mainly concentrated in the urban area with more human activities, and the area between the fifth ring and the sixth ring contributed the most. (3) through scenarios analysis, for further reducing the emission from concrete batching in 2020, more stricter standard for green production as well as powerful supervision is needed.
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Poluentes Atmosféricos/análise , Materiais de Construção , Material Particulado/análise , Pequim , Atividades Humanas , HumanosRESUMO
VOCs emission of service station is one of the main sources of VOCs in Beijing. Uncontrolled emission factor (UEF) of refueling in China, US EPA, EEA respectively is 2.16, 1.31 and 1.00 times of CARB UEF (1008 mg·L-1). China's gasoline standards have changed in the last 20 years, and there is an urgent need to carry out the localization of gasoline refueling VOCs emission factor research. This paper compared test methods for refueling emission factors of European Union (EU) and California Air Resources Board (CARB) and found that the EU method was simpler and easier to operate than the CARB method, so we processed refueling VOCs emission factors test device in reference to EU test methods and chose a set of United States Stage â ¡ vapor recovery system in Beijing service stations to carry out studies on VOCs emission factors. The results showed that: 1 For the fuel test tank, refueling vapor recovery efficiencies were 0.93 and 0.83 times of air to liquid volume ratio (A/L) of Stage â ¡ respectively in winter and summer. Refueling emission factor in summer was greater than that in winter, and its recovery efficiency was lower than that in winter. 2 For the social vehicles, winter and summer refueling UEF respectively was (525±42) mg·L-1 and (963±174) mg·L-1, at the same time was 0.52 and 0.95 times of CARB refueling UEF (1008 mg·L-1) in A/L=0.The average value of emission factors respectively was (55±30) mg·L-1 and (112±108) mg·L-1 in A/L 1.05-1.07 in winter and summer. 3Refueling UEF without vapor recovery of social vehicles was chosen as the localized summer and winter refueling UEF in Beijing, we could calculate the emission factor of vapor recovery in different A/L combining with the linear equation of the fuel test tank.
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In order to understand the formations and the concentrations of the secondary sulfate and nitrate of PM10 in Beijing. From May 2008 to April 2009, MOUDI has been used to collect the PM10 samples in Beijing atmospheric environment and the ion chromatography has been used to analyze the inorganic water-soluble components of the PM10 samples. The results showed that the mass size distributions of soluble sulfate and nitrate of PM10 in Beijing were single-mode distribution and the peak rang was from 0.32 microm to 0.56 microm, and the primary formation ways was the chemical reaction in the gas phase. The results of partial correlation analysis indicated that the primary formations of sulfate and nitrate of PM10 in Beijing was (NH4)2SO4, NH4NO3, NaNO3, KNO3 and Ca(NO3)2. The mass concentration of secondary (NH4)2SO4 and NH4NO3 were (17.0 +/- 8.2) microg/m3 and (8.8 +/- 3.3) microg/m3 respectively, which accounted for (14.7 +/- 3.6)% and (7.6 +/- 2.2)% of PM10 respectively. The sum of them accounted for (22.3 +/- 4.3)% of PM10.
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Poluentes Atmosféricos/análise , Nitratos/análise , Material Particulado/análise , Sulfatos/análise , Atmosfera/análise , China , Cidades , Monitoramento Ambiental , Tamanho da PartículaRESUMO
We established a four-dimensional fluxes mathematics model and a suit of relevant monitoring project that can calculate construction fugitive dust emission according to actual field monitoring data, this mathematics model is similar to exposure profiling method recommended by U.S. EPA. Four-dimensional fluxes mathematics model is simpler and more convenient to calculate construction fugitive dust emission, and it can preferably eliminate the influence of incidental factors on calculation result. Actual field monitoring data from forty construction sites of Beijing were inputted into the model to calculate TSP emission factor among construction fugitive dust of Beijing local which equaled to 0.492 kg/(m2 x 30 d). By comparing emission factor of Beijing and U.S. EPA's AP-42 documents, we found the ratio between Beijing's and U.S. EPA's emission factor value was 1.83. Beijing local emission factor from this paper is recommended to establish construction fugitive dust emission inventory of Beijing.
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Poluentes Atmosféricos/análise , Poeira/análise , Arquitetura de Instituições de Saúde , Modelos Teóricos , Poluição do Ar/prevenção & controle , China , Monitoramento Ambiental/métodosRESUMO
By monitoring the road and construction dust fall continuously during the "Good Luck Beijing" sport events, the reduction of road and construction dust fall caused by traffic restriction was studied. The contribution rate of road and construction dust to particulate matter of Beijing atmosphere environment, and the emission ratio of it to total local PM10 emission were analyzed. The results show that the traffic restriction reduces road and construction dust fall significantly. The dust fall average value of ring roads was 0.27 g x (m2 x d)(-1) in the "traffic restriction" period, and the values were 0.81 and 0.59 g x (m2 x d)(-1) 1 month and 7 days before. The dust fall average value of major arterial and minor arterial was 0.21 g x (m2 x d)(-1) in the "traffic restriction" period, and the values were 0.54 and 0.58 g x (m2 x d)(-1) 1 month and 7 days before. The roads emission reduced 60%-70% compared with before traffic restriction. The dust fall average values of civil architecture and utility architecture were 0.61 and 1.06 g x (m2 x d)(-1) in the "traffic restriction" period, and the values were 1.15 and 1.55 g x (m2 x d)(-1) 20 days before. The construction dust reduced 30%-47% compared with 20 days before traffic restriction. Road and construction dust emission are the main source of atmosphere particulate matter in Beijing, and its contribution to ambient PM10 concentration is 21%-36%. PM10 emitted from roads and constructions account for 42%-72% and 30%-51% of local emission while the local PM10 account for 50% and 70% of the total emission.
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Poluentes Atmosféricos/análise , Poeira/análise , Arquitetura de Instituições de Saúde , Material Particulado/análise , Emissões de Veículos/análise , Poluentes Atmosféricos/química , China , Cidades , Monitoramento Ambiental , Tamanho da PartículaRESUMO
Dust fall was selected as a monitored index of fugitive dust from construction sites. The vertical dispersion law of fugitive dust was studied nearby construction site's boundary by monitoring the concentration variation of dust fall at different heights from 1.5 meters to 4.1 meters. The horizontal dispersion law of fugitive dust was studied along different distance between monitoring points and construction site from 0 meters to 210 meters. We gained the vertical and horizontal dispersion models of fugitive dust by regressing measurement date. The results showed that the concentration of relative dust fall from construction site was proportional to second power of monitoring height, and relative dust fall at uniform height and direction was also proportional to second power of level distance between monitoring points and construction site. The vertical and horizontal dispersion constants are mainly affected by construction activity and natural condition.
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Poluentes Atmosféricos/análise , Poeira/análise , Monitoramento Ambiental , Arquitetura de Instituições de Saúde , China , Material Particulado/análiseRESUMO
In the emission factor models of man-made fugitive dust, the wind velocity parameter has little been accounted for. PM10 concentration and wind velocity were measured near a unpaved road and in a construction site. PM10 emission flux was calculated using the measured data. The relationship between PM10 concentration and emission flux and wind velocity was studied. The results show that the PM10 concentration is high in the condition of static and slight wind. PM10 concentration descend with the wind velocity increased, and the concentration reaches to the minimum value when the wind velocity reach to 1.0-2.0 m/s, then with the wind velocity increasing (> 1.0-2.0 m/s), the PM10 concentration increases quickly. The emission flux increased with the wind velocity increasing, and the speed increasement become more after the wind velocity was faster than 2.0 m/s. The man-made fugitive dust was divided into mechanism operation and wind erosion dust to research the emission mechanism. The results based on theory analysis and the measured data are consistent.
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Poluentes Atmosféricos/análise , Poeira/análise , Arquitetura de Instituições de Saúde , Material Particulado/análise , Vento , Tamanho da PartículaRESUMO
This paper studied the correlation between dust fall and TSP from construction sites in Beijing by statistically analyzing a large number of field measurement data. The results show that there are better linear correlations between dust fall and TSP from construction fugitive dust, and the correlation between dust fall and TSP at construction sites' boundary can be expressed by the function: c(TSP) = 11.6 x c(DF). The distance between monitoring site and fugitive dust source performs a considerable influence on the correlation coefficients that is proportional to the distance. However, construction phases' influence is lesser.
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Poluição do Ar/análise , Poeira/análise , Arquitetura de Instituições de Saúde , Poluentes Atmosféricos/análise , Material Particulado/análiseRESUMO
More than forty construction sites were selected as experimental fields in urban districts and near suburbs of Beijing. Fugitive dust from construction sites was monitored by dust fall. The characteristics of fugitive dust pollution in different construction phases were studied. The frequency distribution of relative dust fall date in different construction phases were statistically analyzed, and the results show that fugitive dust pollution in earthwork phase is more serious than those in structure and decoration phases. There are higher probabilities of high strength fugitive dust pollution in earthwork and decoration phases comparing with structure phase, and the probabilities of relative dust fall which is more than 50 t/(km2 x 30 d) are 16%, 16% and 3% respectively. Different construction phases all comply with the laws that fugitive dust pollution strength in spring is bigger than summer,autumn and winter obviously, and winter is bigger than summer and autumn appreciably. There are obvious relation of fugitive dust pollution strength in different construction phases, and the ratio of pollution strength in earthwork, structure and decoration phases equals to 100:67:87.