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
Between the alternative sources available for the electricity production, still lacks reliability for the production in base units. For the electricity production from 500 MW to 1,000 MW or more, the coal-fired therma...Between the alternative sources available for the electricity production, still lacks reliability for the production in base units. For the electricity production from 500 MW to 1,000 MW or more, the coal-fired thermal and nuclear power plants with uranium have proved competitive and with a high level of reliability and maturation, besides presenting the fuel supply security. This paper presents an analysis of technical feasibility for the choice of the best technology for generating electricity on a large scale, based on coal-fired thermal or nuclear power plant using uranium. This paper takes in account the availability of fuel sources, investments costs, thermal power generation systems, pollutants emission and mitigation technologies, global efficiency, fuel consumption, costs of electricity, construction time and an average lifespan of the installation. Thus the analysis allows the most rational choice of technology for the production of electricity with lower electricity costs and lower COz emissions.展开更多
An exergy life cycle assessment(ELCA) model based on life cycle assessment(LCA) and exergy methodology was developed to assess a 2×300 MW coal-fired power plant,and the results indicated that the exergy input in ...An exergy life cycle assessment(ELCA) model based on life cycle assessment(LCA) and exergy methodology was developed to assess a 2×300 MW coal-fired power plant,and the results indicated that the exergy input in operation phase of power plant accounts for 99.89% of the total input and only 0.11% in construction and decommission phases. Direct and indirect exergy inputs account for 93.03% and 6.97%,respectively. Compared with coal-fired power generation system before carbon emission reduction,exergy input-output ratio of life cycle "CO2 zero-emission" energy system and exergy efficiency are about 5.563 and 17.97%,respectively,which increases by 62.47% and declines by 11.21% approximately. The model quantifies the energy,resource consumption and pollutant emissions of system life cycle using exergy as the basic physical parameter,which will make the assessment more objective and reasonable.展开更多
A 30 kW bench-scale rig of pulverized anthracite combustion preheated by a circulating fluidized bed (CFB) was developed. The CFB riser has a diameter of 90 mm and a height of 1,500 mm. The down-fired combustion cha...A 30 kW bench-scale rig of pulverized anthracite combustion preheated by a circulating fluidized bed (CFB) was developed. The CFB riser has a diameter of 90 mm and a height of 1,500 mm. The down-fired combustion chamber (DFCC) has a diameter of 260 mm and a height of 3,000 mm. Combustion experiments were carded out using pulverized anthracite with 6.74% volatile content. This low volatile coal is difficult to ignite and burn out. Therefore, it requires longer burnout time and higher combustion temperature, which results in larger NOx emis- sions. In the current study, important factors that influence the combustion characteristics and NOx emissions were investigated such as excess air ratio, air ratio in the reducing zone, and fuel residence time in the reducing zone. Pulverized anthracite can be quickly preheated up to 800~C in CFB when the primary air is 24% of theo- retical air for combustion, and the temperature profile is uniform in DFCC. The combustion efficiency is 94.2%, which is competitive with other anthracite combustion technologies. When the excess air ratio ranges from 1.26 to 1.67, the coal-N conversion ratio is less than 32% and the NOx emission concentration is less than 371 mg/m^3 (@6% O2). When the air ratio in the reducing zone is 0.12, the NOx concentration is 221 mg/m^3 (@6% O2), and the coal-N conversion ratio is 21%, which is much lower than that of other boilers.展开更多
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Between the alternative sources available for the electricity production, still lacks reliability for the production in base units. For the electricity production from 500 MW to 1,000 MW or more, the coal-fired thermal and nuclear power plants with uranium have proved competitive and with a high level of reliability and maturation, besides presenting the fuel supply security. This paper presents an analysis of technical feasibility for the choice of the best technology for generating electricity on a large scale, based on coal-fired thermal or nuclear power plant using uranium. This paper takes in account the availability of fuel sources, investments costs, thermal power generation systems, pollutants emission and mitigation technologies, global efficiency, fuel consumption, costs of electricity, construction time and an average lifespan of the installation. Thus the analysis allows the most rational choice of technology for the production of electricity with lower electricity costs and lower COz emissions.
基金supported by the National Natural Science Foundation of China (Grant Nos.40972102,50936001,51021065)the National Basic Research Program of China ("973" Project) (Grant No.2010CB227003)
文摘An exergy life cycle assessment(ELCA) model based on life cycle assessment(LCA) and exergy methodology was developed to assess a 2×300 MW coal-fired power plant,and the results indicated that the exergy input in operation phase of power plant accounts for 99.89% of the total input and only 0.11% in construction and decommission phases. Direct and indirect exergy inputs account for 93.03% and 6.97%,respectively. Compared with coal-fired power generation system before carbon emission reduction,exergy input-output ratio of life cycle "CO2 zero-emission" energy system and exergy efficiency are about 5.563 and 17.97%,respectively,which increases by 62.47% and declines by 11.21% approximately. The model quantifies the energy,resource consumption and pollutant emissions of system life cycle using exergy as the basic physical parameter,which will make the assessment more objective and reasonable.
基金supported by the National Natural Science Foundation of China(51006103)
文摘A 30 kW bench-scale rig of pulverized anthracite combustion preheated by a circulating fluidized bed (CFB) was developed. The CFB riser has a diameter of 90 mm and a height of 1,500 mm. The down-fired combustion chamber (DFCC) has a diameter of 260 mm and a height of 3,000 mm. Combustion experiments were carded out using pulverized anthracite with 6.74% volatile content. This low volatile coal is difficult to ignite and burn out. Therefore, it requires longer burnout time and higher combustion temperature, which results in larger NOx emis- sions. In the current study, important factors that influence the combustion characteristics and NOx emissions were investigated such as excess air ratio, air ratio in the reducing zone, and fuel residence time in the reducing zone. Pulverized anthracite can be quickly preheated up to 800~C in CFB when the primary air is 24% of theo- retical air for combustion, and the temperature profile is uniform in DFCC. The combustion efficiency is 94.2%, which is competitive with other anthracite combustion technologies. When the excess air ratio ranges from 1.26 to 1.67, the coal-N conversion ratio is less than 32% and the NOx emission concentration is less than 371 mg/m^3 (@6% O2). When the air ratio in the reducing zone is 0.12, the NOx concentration is 221 mg/m^3 (@6% O2), and the coal-N conversion ratio is 21%, which is much lower than that of other boilers.