Air pollution is a major global issue with widely known harmful effects on human health and the environment. This pollution is a very complex phenomenon given the diversity of pollutants that may be present in the atm...Air pollution is a major global issue with widely known harmful effects on human health and the environment. This pollution is a very complex phenomenon given the diversity of pollutants that may be present in the atmosphere. The air quality in urban areas is of a great concern for residents living in cities and represents a current issue that requires an adequate management. So that air quality policy is driven by health concerns. In this paper, we present an overview on the experience of Agadir city to establish the air quality management policy, local authority on the whole have developed a good understanding of air quality in the area. Indeed for several years, efforts have been made to monitor the air quality in this city, this translated by air quality assessment since 2006 using mobile laboratory and fixed station. Our goals in this study were to review the operation of Local Air Quality Management (LAQM) making better use of available resources to improve its outcomes and make recommendations with a view to improving air quality issues. This work highlights the requirement to revise periodically the LAQM for generating priority for air quality issues within local authority and the need to implement the optimizing Air Quality Monitoring Network (AQMN).展开更多
The total emission control method based on atmospheric environmental capacity is the most effective in air pollution mitigation. The atmospheric environmental capacities of SO2 on representative days over Lanzhou are ...The total emission control method based on atmospheric environmental capacity is the most effective in air pollution mitigation. The atmospheric environmental capacities of SO2 on representative days over Lanzhou are estimated using the numerical models RAMS, HYPACT and a linear programming model, according to the national ambient air quality standard of China (NAAQSCHN). The results show that the fields of meteorological elements and SO2 simulated by the models agree reasonably well with observations. The atmospheric environmental capacity of SO2 over Lanzhou is around 111.7 × 10^3 kg d^-1, and in order to meet the air quality level Ⅱ of the NAAQSCHN, SO2 emissions need to be reduced by 20%.展开更多
A 600 MW coal-fired boiler with a four-corner tangential combustion mode is considered here to study the combustion features and pollutant emissions at different loads for large-percentages of blending dried sludges.T...A 600 MW coal-fired boiler with a four-corner tangential combustion mode is considered here to study the combustion features and pollutant emissions at different loads for large-percentages of blending dried sludges.The influence of the over-fired air(OFA)coefficient is examined and the impact of the blending ratio on the boiler operation is explored.The results show that for low blending ratios,a slight increase in the blending ratio can improve the combustion of bituminite,whereas a further increase leads to the deterioration of the combustion of blended fuels and thus reduces the boiler efficiency.Enhancing the supporting capability of the secondary air effectively reduces the slagging degree in the bottom ash hopper and improves the burnout rate of coals.For a large-percentage blending case at full load,it is found that the OFA coefficient must be reduced appropriately,otherwise,a secondary high-temperature combustion zone can be generated in the vicinity of the furnace arches,causing high temperature slagging and superheater tube bursting.Considering the influences of combustion and pollutant emissions,the recommended OFA coefficient is 0.2.Blending dried sludge under low loads increases the flue gas temperature at the furnace exit.While reducing the flue gas temperature in the main combustion region,which is beneficial to the safe operation of the denitrification system.Increasing the blending ratio and reducing load lead to an increase in NOx concentration at the furnace exit Sludges with low nitrogen content are suggested for the practical operation of boilers.展开更多
The lack of data on air quality monitoring and neglected and overlooked pollutant emissions in the transportation and industrial sectors are motives for the government of Senegal to set up, in 2009, an air quality man...The lack of data on air quality monitoring and neglected and overlooked pollutant emissions in the transportation and industrial sectors are motives for the government of Senegal to set up, in 2009, an air quality management center, the CGQA</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">(Centre de Gestion de la Qualité de l’Air). Air quality monitoring at CGQA deals with mainly six pollutants: carbon monoxide (CO), nitrogen oxides (NO</span><sub><span style="font-family:Verdana;">x</span></sub><span style="font-family:Verdana;">) (with nitrogen dioxide (NO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">) and nitrogen monoxide </span><span><span style="font-family:Verdana;">(NO)), sulfur dioxide (SO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">), ground-level ozone (O</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">), Benzene-Toluene-Xylenes</span></span><span style="font-family:Verdana;"> (BTX), and particulate matters (PM) with diameters less than 10 μm (PM</span><sub><span style="font-family:Verdana;">10</span></sub><span style="font-family:Verdana;">) and 2.5 μm (PM</span><sub><span style="font-family:Verdana;">2.5</span></sub><span style="font-family:Verdana;">). The concentration levels of gaseous pollutants (CO, O</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">, NO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> and SO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">) in the city generally remain below the limit value set by the WHO (World Health Organization). However, particulate matters (PM</span><sub><span style="font-family:Verdana;">10</span></sub><span style="font-family:Verdana;"> and PM</span><sub><span style="font-family:Verdana;">2.5</span></sub><span style="font-family:Verdana;">) are the most important pollutants observed in Dakar, they far exceed the annual thresholds set by the WHO and the national standard (NS 05-062). This situation results in an Air Quality Index (AQI) around bad and very bad during the dry season (November to May) and good to moderate during the rainy season (June to October). The concentrations of PM</span><sub><span style="font-family:Verdana;">10</span></sub><span style="font-family:Verdana;"> and PM</span><sub><span style="font-family:Verdana;">2.5</span></sub><span style="font-family:Verdana;"> vary respectively from 120 to 180 μg</span></span><span style="font-family:Verdana;">·</span><span style="font-family:Verdana;">m</span><sup><span style="font-family:Verdana;">-</span></sup><sup><span style="font-family:Verdana;">3</span></sup><span style="font-family:Verdana;"> and from 25 to 48 μg</span><span style="font-family:Verdana;">·</span><span style="font-family:Verdana;">m</span><sup><span style="font-family:Verdana;">-</span></sup><sup><span style="font-family:Verdana;">3</span></sup><span style="font-family:Verdana;">. The average concentrations of pollutants therefore vary from one area to another and depending on the location of the air quality monitoring station (near industrial sites, traffic, etc.).展开更多
Due to the increasingly stringent standards, it is important to assess whether the proposed emission reduction will result in ambient concentrations that meet the standards. The Software for Model Attainment Test-Comm...Due to the increasingly stringent standards, it is important to assess whether the proposed emission reduction will result in ambient concentrations that meet the standards. The Software for Model Attainment Test-Community Edition (SMAT-CE) is developed for demonstrating attainment of air quality standards of O3 and PM2.5. SMAT-CE improves computational efficiency and provides a number of advanced visualization and analytical functionalities on an integrated GIS platform. SMAT-CE incorporates historical measurements of air quality parameters and simulated air pollutant concentrations under a number of emission inventory scenarios to project the level of compliance to air quality standards in a targeted future year. An application case study of the software based on the U.S. National Ambient Air Quality Standards (NAAQS) shows that SMAT-CE is capable of demonstrating the air quality attainment of annual PM2.5 and 8-hour O3 for a proposed emission control policy.展开更多
文摘Air pollution is a major global issue with widely known harmful effects on human health and the environment. This pollution is a very complex phenomenon given the diversity of pollutants that may be present in the atmosphere. The air quality in urban areas is of a great concern for residents living in cities and represents a current issue that requires an adequate management. So that air quality policy is driven by health concerns. In this paper, we present an overview on the experience of Agadir city to establish the air quality management policy, local authority on the whole have developed a good understanding of air quality in the area. Indeed for several years, efforts have been made to monitor the air quality in this city, this translated by air quality assessment since 2006 using mobile laboratory and fixed station. Our goals in this study were to review the operation of Local Air Quality Management (LAQM) making better use of available resources to improve its outcomes and make recommendations with a view to improving air quality issues. This work highlights the requirement to revise periodically the LAQM for generating priority for air quality issues within local authority and the need to implement the optimizing Air Quality Monitoring Network (AQMN).
基金the National Natural Science Foundation of China (Grant No. 40305020).
文摘The total emission control method based on atmospheric environmental capacity is the most effective in air pollution mitigation. The atmospheric environmental capacities of SO2 on representative days over Lanzhou are estimated using the numerical models RAMS, HYPACT and a linear programming model, according to the national ambient air quality standard of China (NAAQSCHN). The results show that the fields of meteorological elements and SO2 simulated by the models agree reasonably well with observations. The atmospheric environmental capacity of SO2 over Lanzhou is around 111.7 × 10^3 kg d^-1, and in order to meet the air quality level Ⅱ of the NAAQSCHN, SO2 emissions need to be reduced by 20%.
文摘A 600 MW coal-fired boiler with a four-corner tangential combustion mode is considered here to study the combustion features and pollutant emissions at different loads for large-percentages of blending dried sludges.The influence of the over-fired air(OFA)coefficient is examined and the impact of the blending ratio on the boiler operation is explored.The results show that for low blending ratios,a slight increase in the blending ratio can improve the combustion of bituminite,whereas a further increase leads to the deterioration of the combustion of blended fuels and thus reduces the boiler efficiency.Enhancing the supporting capability of the secondary air effectively reduces the slagging degree in the bottom ash hopper and improves the burnout rate of coals.For a large-percentage blending case at full load,it is found that the OFA coefficient must be reduced appropriately,otherwise,a secondary high-temperature combustion zone can be generated in the vicinity of the furnace arches,causing high temperature slagging and superheater tube bursting.Considering the influences of combustion and pollutant emissions,the recommended OFA coefficient is 0.2.Blending dried sludge under low loads increases the flue gas temperature at the furnace exit.While reducing the flue gas temperature in the main combustion region,which is beneficial to the safe operation of the denitrification system.Increasing the blending ratio and reducing load lead to an increase in NOx concentration at the furnace exit Sludges with low nitrogen content are suggested for the practical operation of boilers.
文摘The lack of data on air quality monitoring and neglected and overlooked pollutant emissions in the transportation and industrial sectors are motives for the government of Senegal to set up, in 2009, an air quality management center, the CGQA</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">(Centre de Gestion de la Qualité de l’Air). Air quality monitoring at CGQA deals with mainly six pollutants: carbon monoxide (CO), nitrogen oxides (NO</span><sub><span style="font-family:Verdana;">x</span></sub><span style="font-family:Verdana;">) (with nitrogen dioxide (NO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">) and nitrogen monoxide </span><span><span style="font-family:Verdana;">(NO)), sulfur dioxide (SO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">), ground-level ozone (O</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">), Benzene-Toluene-Xylenes</span></span><span style="font-family:Verdana;"> (BTX), and particulate matters (PM) with diameters less than 10 μm (PM</span><sub><span style="font-family:Verdana;">10</span></sub><span style="font-family:Verdana;">) and 2.5 μm (PM</span><sub><span style="font-family:Verdana;">2.5</span></sub><span style="font-family:Verdana;">). The concentration levels of gaseous pollutants (CO, O</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">, NO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> and SO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">) in the city generally remain below the limit value set by the WHO (World Health Organization). However, particulate matters (PM</span><sub><span style="font-family:Verdana;">10</span></sub><span style="font-family:Verdana;"> and PM</span><sub><span style="font-family:Verdana;">2.5</span></sub><span style="font-family:Verdana;">) are the most important pollutants observed in Dakar, they far exceed the annual thresholds set by the WHO and the national standard (NS 05-062). This situation results in an Air Quality Index (AQI) around bad and very bad during the dry season (November to May) and good to moderate during the rainy season (June to October). The concentrations of PM</span><sub><span style="font-family:Verdana;">10</span></sub><span style="font-family:Verdana;"> and PM</span><sub><span style="font-family:Verdana;">2.5</span></sub><span style="font-family:Verdana;"> vary respectively from 120 to 180 μg</span></span><span style="font-family:Verdana;">·</span><span style="font-family:Verdana;">m</span><sup><span style="font-family:Verdana;">-</span></sup><sup><span style="font-family:Verdana;">3</span></sup><span style="font-family:Verdana;"> and from 25 to 48 μg</span><span style="font-family:Verdana;">·</span><span style="font-family:Verdana;">m</span><sup><span style="font-family:Verdana;">-</span></sup><sup><span style="font-family:Verdana;">3</span></sup><span style="font-family:Verdana;">. The average concentrations of pollutants therefore vary from one area to another and depending on the location of the air quality monitoring station (near industrial sites, traffic, etc.).
基金provided by the U.S. Environmental Protection Agency (Subcontract Number OR13810-001.04 A10-0223-S001-A04)partly supported by the funding of Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control (No. 2011A060901011)+1 种基金the funding of State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex (No. SCAPC201308)the project of Atmospheric Haze Collaborative Control System Design (No. XDB05030400) from Chinese Academy of Sciences
文摘Due to the increasingly stringent standards, it is important to assess whether the proposed emission reduction will result in ambient concentrations that meet the standards. The Software for Model Attainment Test-Community Edition (SMAT-CE) is developed for demonstrating attainment of air quality standards of O3 and PM2.5. SMAT-CE improves computational efficiency and provides a number of advanced visualization and analytical functionalities on an integrated GIS platform. SMAT-CE incorporates historical measurements of air quality parameters and simulated air pollutant concentrations under a number of emission inventory scenarios to project the level of compliance to air quality standards in a targeted future year. An application case study of the software based on the U.S. National Ambient Air Quality Standards (NAAQS) shows that SMAT-CE is capable of demonstrating the air quality attainment of annual PM2.5 and 8-hour O3 for a proposed emission control policy.