Northeast China has been reported as having serious air pollution in China with increasing occurrences of severe haze epi- sodes. Changchun City, as the center of Northeast China, has longstanding industry and is an i...Northeast China has been reported as having serious air pollution in China with increasing occurrences of severe haze epi- sodes. Changchun City, as the center of Northeast China, has longstanding industry and is an important agricultural base. Additionally, Changchun City has a long winter requiring heating of buildings emitting pollution into the air. These factors contribute to the complex- ity of haze pollution in this area. In order to analyze the causes of heavy haze, surface air quality has been monitored from 2013 to 2015. By using satellite and meteorological data, atmospheric pollution status, spatio-temporal variations and formation have been analyzed. Results indicated that the air quality in 88.9% of days exceeding air quality index (AQI) level-1 standard (AQI 〉50) according to the National Ambient Air Quality Standard (NAAQS) of China. Conversely, 33.7% of the days showed a higher level with AQI 〉 100. Ex- treme haze events (AQI 〉 300) occurred frequently during agricultural harvesting period (from October 10 to November 10), intensive winter heating period (from Late-December to February) and period of spring windblown dust (April and May). Most daily concentra- tions of gaseous pollutants, i.e., NO2 (43.8 gg/m3), CO (0.9 mg/m3), SO2 (37.9 gg/m3), and 03 (74.9 gg/m3) were evaluated within level-1 concentration limits of NAAQS standards. However, particulate matter (PM2.5 and PMI0) concentrations (67.3 ~tg/m3and 115.2 ~g/m3, respectively) were significantly higher than their level-1 limits. Severe haze in spring was caused by offsite transported dust and windblown surface soil. Heavy haze periods during fall and winter were mainly formed by intensive emissions of atmospheric pollutants and steady weather conditions (i.e., low wind speed and inversion layer). The overlay emissions of widespread straw burning and coal combustion for heating were the dominant factors contributing to haze in autumn, while intensive coal burning during the coldest time was the primary component of total emissions. In addition, general emissions including automobile exhaust, road and construction dust, residential and industrial activities, have significantly increased in recent years, making heavy haze a more frequent occurrence. There- fore, both improved technological strategies and optimized pollution management on a regional scale are necessary to minimize emis- sions in specified seasons in Changchun City, as well as comprehensive control measures in Northeast China.展开更多
The Emission Standards of Air Pollutants from Thermal Power Plants (GB 13223-2011) prescribe a stricter limitation to air pollutants than ever before. As set in the new emission standard, the limitations of SO2 and NO...The Emission Standards of Air Pollutants from Thermal Power Plants (GB 13223-2011) prescribe a stricter limitation to air pollutants than ever before. As set in the new emission standard, the limitations of SO2 and NOX for sensitive areas under normal conditions are 50 mg/m3 and 100 mg/m3, respectively. The objective analysis and suggestions are proposed. The recent status and operational experience of desulfurization and denitrification equipment are discussed. From the discussions, thermal power plants face a huge challenge to satisfy the new emission standards. For further reducing of the emission concentrations of SO2 and NOX, three methods were introduced, including: seriously implementing the emission standards, improving treatment equipment, and increasing the efficiencies of desulfurization and denitrification.展开更多
Black carbon (BC) aerosol, accounting for a minor fraction of atmospheric aerosols, is attracting increased attentio1 due to its impact on air quality, human health, and climate change. Focusing on BC emission reduc...Black carbon (BC) aerosol, accounting for a minor fraction of atmospheric aerosols, is attracting increased attentio1 due to its impact on air quality, human health, and climate change. Focusing on BC emission reduction, this paper give1 a brief introduction to the sources and global distribution of BC. Along with the decrease of BC emissions from sue1 actions as the reduction of global greenhouse gases (GHGs) and regulating local air quality, it also highlights othet BC reduction approaches such as control and improvement of combustion conditions, the elimination of open biomas burning, and the sequestration of BC by biomass pyrolysis. Finally, it is stressed that at this moment there is no enougt reason to push BC reduction into any climate change related negotiations, although BC has been included in some o so-called win-win reduction targets for the quick response to both climate and non-climate appeals.展开更多
基金Under the auspices of National Key Research and Development Project(No.2017YFC0212300)Youth Innovation Promotion Association CAS(No.2017275)Frontier Science Research Plan CAS(No.QYZDB-SSW-DQC045)
文摘Northeast China has been reported as having serious air pollution in China with increasing occurrences of severe haze epi- sodes. Changchun City, as the center of Northeast China, has longstanding industry and is an important agricultural base. Additionally, Changchun City has a long winter requiring heating of buildings emitting pollution into the air. These factors contribute to the complex- ity of haze pollution in this area. In order to analyze the causes of heavy haze, surface air quality has been monitored from 2013 to 2015. By using satellite and meteorological data, atmospheric pollution status, spatio-temporal variations and formation have been analyzed. Results indicated that the air quality in 88.9% of days exceeding air quality index (AQI) level-1 standard (AQI 〉50) according to the National Ambient Air Quality Standard (NAAQS) of China. Conversely, 33.7% of the days showed a higher level with AQI 〉 100. Ex- treme haze events (AQI 〉 300) occurred frequently during agricultural harvesting period (from October 10 to November 10), intensive winter heating period (from Late-December to February) and period of spring windblown dust (April and May). Most daily concentra- tions of gaseous pollutants, i.e., NO2 (43.8 gg/m3), CO (0.9 mg/m3), SO2 (37.9 gg/m3), and 03 (74.9 gg/m3) were evaluated within level-1 concentration limits of NAAQS standards. However, particulate matter (PM2.5 and PMI0) concentrations (67.3 ~tg/m3and 115.2 ~g/m3, respectively) were significantly higher than their level-1 limits. Severe haze in spring was caused by offsite transported dust and windblown surface soil. Heavy haze periods during fall and winter were mainly formed by intensive emissions of atmospheric pollutants and steady weather conditions (i.e., low wind speed and inversion layer). The overlay emissions of widespread straw burning and coal combustion for heating were the dominant factors contributing to haze in autumn, while intensive coal burning during the coldest time was the primary component of total emissions. In addition, general emissions including automobile exhaust, road and construction dust, residential and industrial activities, have significantly increased in recent years, making heavy haze a more frequent occurrence. There- fore, both improved technological strategies and optimized pollution management on a regional scale are necessary to minimize emis- sions in specified seasons in Changchun City, as well as comprehensive control measures in Northeast China.
文摘The Emission Standards of Air Pollutants from Thermal Power Plants (GB 13223-2011) prescribe a stricter limitation to air pollutants than ever before. As set in the new emission standard, the limitations of SO2 and NOX for sensitive areas under normal conditions are 50 mg/m3 and 100 mg/m3, respectively. The objective analysis and suggestions are proposed. The recent status and operational experience of desulfurization and denitrification equipment are discussed. From the discussions, thermal power plants face a huge challenge to satisfy the new emission standards. For further reducing of the emission concentrations of SO2 and NOX, three methods were introduced, including: seriously implementing the emission standards, improving treatment equipment, and increasing the efficiencies of desulfurization and denitrification.
基金co-supported by China 973 project of MOST(2011CB403401)China Postdoctoral Science Foundation(20080440463,200902157)
文摘Black carbon (BC) aerosol, accounting for a minor fraction of atmospheric aerosols, is attracting increased attentio1 due to its impact on air quality, human health, and climate change. Focusing on BC emission reduction, this paper give1 a brief introduction to the sources and global distribution of BC. Along with the decrease of BC emissions from sue1 actions as the reduction of global greenhouse gases (GHGs) and regulating local air quality, it also highlights othet BC reduction approaches such as control and improvement of combustion conditions, the elimination of open biomas burning, and the sequestration of BC by biomass pyrolysis. Finally, it is stressed that at this moment there is no enougt reason to push BC reduction into any climate change related negotiations, although BC has been included in some o so-called win-win reduction targets for the quick response to both climate and non-climate appeals.