This paper examines project⁃based policies and regulations implemented globally to control and mitigate emissions from diesel⁃powered construction equipment.This study systematically reviews and analyzes various manag...This paper examines project⁃based policies and regulations implemented globally to control and mitigate emissions from diesel⁃powered construction equipment.This study systematically reviews and analyzes various managerial,regulatory,and technical measures adopted across countries and regions,mostly of advanced economy.Key strategies of control include setting emission thresholds,idling restrictions,perform remote online monitoring,operational time limits,setting low emission zones,and enforced registration systems.The review highlights the rationale,implementation details,and experiences gained from these localized approaches,reduces localized emission sources,improve urban air quality and environmental management efficiency.展开更多
The ultra-supercritical pressure coal-fired power-generation technology (USCT) isa mature, advanced and efficient power generation technology in the world. Comparisonsamong several principal clean coal power-generatio...The ultra-supercritical pressure coal-fired power-generation technology (USCT) isa mature, advanced and efficient power generation technology in the world. Comparisonsamong several principal clean coal power-generation technologies show that USCT withpollutant-emission control equipment is superior to others in efficiency, capacity, reliability,investment and environment protection etc. Analyzing the main problems existing in thermalpower industry, it is concluded that the USCT is the preferential choice for China to developclean coal power-generation technology at present. Considering the foundation of thepower industry, the manufacturing industry for power generating equipment and otherrelated industries, it is concluded that China has satisfied the qualifications to develop USCT.展开更多
This paper describes the relation and difference of "emission up to standards" and "total quantity control" ofmain atmospheric pollutants, as well as their legal status. It points out that the tota...This paper describes the relation and difference of "emission up to standards" and "total quantity control" ofmain atmospheric pollutants, as well as their legal status. It points out that the total quantity control is a good approachto solve a problem that environmental quality do not yet reach the requirements in an area where emission concentrationhas came up to standards, or to solve a problem that the interregional transportation of pollutants (e. g. acid rain) arises.And further, it put forward five proposals for the total quantity control.[展开更多
The PM2.5 （particulate matter with a diameter of less than 2.5 μm） trends during the period 2013- 2015, in 13 cities over the Beijing-Tianjin-Hebei region, and their causes, were investigated using observations at ...The PM2.5 （particulate matter with a diameter of less than 2.5 μm） trends during the period 2013- 2015, in 13 cities over the Beijing-Tianjin-Hebei region, and their causes, were investigated using observations at 75 stations and a regional air quality model. It was found that annual PM2.5 in this region experienced a significant decrease in 2014 and 2015, compared with 2013. PM2.s in 2015 almost met the target on air quality in the 13th Five-Year Plan （2012-2017）. In southern cities （e.g. Xingtai, Handan, Shijiazhuang, and Cangzhou）, this PM2.5 decreasing trend was caused by both meteorological conditions and regional emission controls in 2014 and 2015. Contributions from regional emission controls were more significant than meteorological conditions. In Tianjin and Langfang, the impact of regional emission controls was partly offset by the meteorological conditions in 2014. In 2015, meteorological conditions turned favorable for a PM2.s decrease, but emission controls were still the dominant cause. Compared with polluted cities in Hebei and Tianjin, the decreasing trend in Beijing was small （4% and 9% in 2014 and 2015）.This reflects the competition between adverse meteorological conditions and emission controls. In northern cities （Tangshan, Qinhuangdao, and Zhangjiakou）, regional emission controls dominated the PM2.5 decreasing trend in 2014 and 2015, although they were partly offset by meteorological conditions. In all cities during the heating season in 2015, a more significant decreasing trend of high PM2.5 from emission controls was found than low and middle PM2.5. This indicates that air pollution controls are developing towards refined management （e.g. the Heavy Air Pollution Emergency Response Program） in this region.展开更多
Air pollution in modern city and industrial zones has become a serious public concern in recent years in China. Significance of air quality assessment and emission control strategy design is increasing. Most studies i...Air pollution in modern city and industrial zones has become a serious public concern in recent years in China. Significance of air quality assessment and emission control strategy design is increasing. Most studies in China focus on particulate matter(PM), especially PM2.5, while few account for photochemical secondary air pollutions represented by ozone(O3). In this paper, a procedure for air quality simulation with comprehensive air quality model with extensions(CAMx) is demonstrated for studying the photochemical process and ozone generation in the troposphere. As a case study, the CAMx photochemical grid model is used to model ozone over southern part of Beijing city in winter, 2011. The input parameters to CAMx include emission sources, meteorology field data, terrain definition, photolysis status, initial and boundary conditions. The simulation results are verified by theoretical analysis of the ozone generation tendency. The simulated variation tendency of domain-wide average value of hourly ozone concentration coincides reasonably well with the theoretical analysis on the atmospheric photochemical process, demonstrating the effectiveness of the procedure. An integrated model system that cooperates with CAMx will be established in our future work.展开更多
In this paper the premixed catalytic combustion emissions such as CO, unburned hydrocarbon (UHC), NOx and the temperature distribution in the catalytic monolith with ultra low concentration of Pd were studied. Three t...In this paper the premixed catalytic combustion emissions such as CO, unburned hydrocarbon (UHC), NOx and the temperature distribution in the catalytic monolith with ultra low concentration of Pd were studied. Three types of monoliths were used for experiments and the temperature of preheated air was respectively 50℃ , 100℃ and 200℃ . The results showed that preheated air made radial temperature in the catalytic monolith uniform which helped to avoid local hot spots so as to decrease NOx emission. The experiment also proved that the shorter monolith showed much better catalytic combustion performance than longer one and the temperature at the exit of the shorter monolith was relatively lower. On the contrary, the temperature was higher in the longer monolith and the lethal NOx emission was slightly increased.展开更多
In recent years, there have been considerable developments in energy provision with the growing improvements in energy supply security and support systems in China. However, China's energy system continues to reta...In recent years, there have been considerable developments in energy provision with the growing improvements in energy supply security and support systems in China. However, China's energy system continues to retain a high-carbon feature where coal dominates energy production and consumption, which has led to the rapid growth of greenhouse gas emissions and associated serious environmental pollution. It has therefore become an important task for China to consider how to promote the low-carbon development of energy system. This paper summarized the basic trends and challenges for development of low-carbon energy system in China and studied the primary energy consumption and carbon emissions in different scenarios at 10-year intervals between 2010 and 2050. The analysis showed that controlling coal consumption will have an important influence on the control of total carbon emissions and of carbon emission peaking; promotion of non-fossil fuel energies will offer a growing contribution to a low-carbon transition in the medium and long term; the development of carbon capture, utilization, and storage will play a key role in realizing a deep decarbonization pathway, particularly after 2030; and the establishment of a low-carbon power system is crucial for the achievement of low-carbon energy transition. Finally, the strategic considerations and policy suggestions on the development of low-carbon energy systems in China are explored.展开更多
基金Research Grants Council of the Hong Kong Special Administrative Region,China(U15239024)。
文摘This paper examines project⁃based policies and regulations implemented globally to control and mitigate emissions from diesel⁃powered construction equipment.This study systematically reviews and analyzes various managerial,regulatory,and technical measures adopted across countries and regions,mostly of advanced economy.Key strategies of control include setting emission thresholds,idling restrictions,perform remote online monitoring,operational time limits,setting low emission zones,and enforced registration systems.The review highlights the rationale,implementation details,and experiences gained from these localized approaches,reduces localized emission sources,improve urban air quality and environmental management efficiency.
文摘The ultra-supercritical pressure coal-fired power-generation technology (USCT) isa mature, advanced and efficient power generation technology in the world. Comparisonsamong several principal clean coal power-generation technologies show that USCT withpollutant-emission control equipment is superior to others in efficiency, capacity, reliability,investment and environment protection etc. Analyzing the main problems existing in thermalpower industry, it is concluded that the USCT is the preferential choice for China to developclean coal power-generation technology at present. Considering the foundation of thepower industry, the manufacturing industry for power generating equipment and otherrelated industries, it is concluded that China has satisfied the qualifications to develop USCT.
文摘This paper describes the relation and difference of "emission up to standards" and "total quantity control" ofmain atmospheric pollutants, as well as their legal status. It points out that the total quantity control is a good approachto solve a problem that environmental quality do not yet reach the requirements in an area where emission concentrationhas came up to standards, or to solve a problem that the interregional transportation of pollutants (e. g. acid rain) arises.And further, it put forward five proposals for the total quantity control.[
基金supported by the Chinese Key Projects in the National Science & Technology Pillar Program[grant number2014BAC06B03]the National Key Project of Basic Research[grant number 2014CB447900]+1 种基金the Strategic Priority Research Program of Chinese Academy of Sciences[grant number XDB05030101]the National Natural Science Foundation of China[grant numbers 41571130034,91544227]
文摘The PM2.5 （particulate matter with a diameter of less than 2.5 μm） trends during the period 2013- 2015, in 13 cities over the Beijing-Tianjin-Hebei region, and their causes, were investigated using observations at 75 stations and a regional air quality model. It was found that annual PM2.5 in this region experienced a significant decrease in 2014 and 2015, compared with 2013. PM2.s in 2015 almost met the target on air quality in the 13th Five-Year Plan （2012-2017）. In southern cities （e.g. Xingtai, Handan, Shijiazhuang, and Cangzhou）, this PM2.5 decreasing trend was caused by both meteorological conditions and regional emission controls in 2014 and 2015. Contributions from regional emission controls were more significant than meteorological conditions. In Tianjin and Langfang, the impact of regional emission controls was partly offset by the meteorological conditions in 2014. In 2015, meteorological conditions turned favorable for a PM2.s decrease, but emission controls were still the dominant cause. Compared with polluted cities in Hebei and Tianjin, the decreasing trend in Beijing was small （4% and 9% in 2014 and 2015）.This reflects the competition between adverse meteorological conditions and emission controls. In northern cities （Tangshan, Qinhuangdao, and Zhangjiakou）, regional emission controls dominated the PM2.5 decreasing trend in 2014 and 2015, although they were partly offset by meteorological conditions. In all cities during the heating season in 2015, a more significant decreasing trend of high PM2.5 from emission controls was found than low and middle PM2.5. This indicates that air pollution controls are developing towards refined management （e.g. the Heavy Air Pollution Emergency Response Program） in this region.
文摘Air pollution in modern city and industrial zones has become a serious public concern in recent years in China. Significance of air quality assessment and emission control strategy design is increasing. Most studies in China focus on particulate matter(PM), especially PM2.5, while few account for photochemical secondary air pollutions represented by ozone(O3). In this paper, a procedure for air quality simulation with comprehensive air quality model with extensions(CAMx) is demonstrated for studying the photochemical process and ozone generation in the troposphere. As a case study, the CAMx photochemical grid model is used to model ozone over southern part of Beijing city in winter, 2011. The input parameters to CAMx include emission sources, meteorology field data, terrain definition, photolysis status, initial and boundary conditions. The simulation results are verified by theoretical analysis of the ozone generation tendency. The simulated variation tendency of domain-wide average value of hourly ozone concentration coincides reasonably well with the theoretical analysis on the atmospheric photochemical process, demonstrating the effectiveness of the procedure. An integrated model system that cooperates with CAMx will be established in our future work.
基金Supported by the Key Project of the National 973 Program of China (No.2005CB724201)the Natural Science Foundation ofBeijing (No.06C0002)the Beijing Education Commission Key Laboratory of Heat Transfer and Energy Conversion Fund(No.05005790200406).
文摘In this paper the premixed catalytic combustion emissions such as CO, unburned hydrocarbon (UHC), NOx and the temperature distribution in the catalytic monolith with ultra low concentration of Pd were studied. Three types of monoliths were used for experiments and the temperature of preheated air was respectively 50℃ , 100℃ and 200℃ . The results showed that preheated air made radial temperature in the catalytic monolith uniform which helped to avoid local hot spots so as to decrease NOx emission. The experiment also proved that the shorter monolith showed much better catalytic combustion performance than longer one and the temperature at the exit of the shorter monolith was relatively lower. On the contrary, the temperature was higher in the longer monolith and the lethal NOx emission was slightly increased.
文摘In recent years, there have been considerable developments in energy provision with the growing improvements in energy supply security and support systems in China. However, China's energy system continues to retain a high-carbon feature where coal dominates energy production and consumption, which has led to the rapid growth of greenhouse gas emissions and associated serious environmental pollution. It has therefore become an important task for China to consider how to promote the low-carbon development of energy system. This paper summarized the basic trends and challenges for development of low-carbon energy system in China and studied the primary energy consumption and carbon emissions in different scenarios at 10-year intervals between 2010 and 2050. The analysis showed that controlling coal consumption will have an important influence on the control of total carbon emissions and of carbon emission peaking; promotion of non-fossil fuel energies will offer a growing contribution to a low-carbon transition in the medium and long term; the development of carbon capture, utilization, and storage will play a key role in realizing a deep decarbonization pathway, particularly after 2030; and the establishment of a low-carbon power system is crucial for the achievement of low-carbon energy transition. Finally, the strategic considerations and policy suggestions on the development of low-carbon energy systems in China are explored.
