A double reheat ultra-supercritical boiler is an important development direction for high-parameter and large-capacity coal-fired power plants due to its high thermal efficiency and environmental value.China has devel...A double reheat ultra-supercritical boiler is an important development direction for high-parameter and large-capacity coal-fired power plants due to its high thermal efficiency and environmental value.China has developed a 1000 MW double reheat ultra-supercritical boiler with steam parameters of 35 MPa at 605℃/613℃/613℃.Reasonable water wall design is one of the keys to safe and reliable operation of the boiler.In order to examine the thermal-hydraulic characteristics of the double reheat ultra-supercritical boiler,the water wall system was equivalent to a flow network comprising series-parallel circuits,linking circuits and pressure nodes,and a calculation model was built on account of the conservation equations of energy,momentum and mass.Through the iterative solving of nonlinear equations,the prediction parameters of the water wall at boiler maximum continue rate(BMCR),75%turbine heat-acceptance rate(THA)and 30%THA loads,including total pressure drops,flow distribution,outlet steam temperatures,fluid and metal temperatures were gotten.The results of calculation exhibit excellent thermal-hydraulic characteristics and substantiate the feasibility of the water wall design of the double reheat ultra-supercritical boiler.展开更多
The advanced ultra-supercritical power plants of the future will utilize steam pressures and temperatures that are too high for traditional ferritic steels,thus requiring austenitic materials.Older nickel-base superal...The advanced ultra-supercritical power plants of the future will utilize steam pressures and temperatures that are too high for traditional ferritic steels,thus requiring austenitic materials.Older nickel-base superalloys such as 263 and 617 were initially evaluated under the European THERMIE project beginning in the 1990s.An entirely new age-hardened alloy 740 which possesses exceptional fireside corrosion resistance and creep strength was also developed for boiler tubing capable of serving at 700C.Subsequently,interest in the USA considered other product forms such as steam header piping and steam turbine forgings for service as high as 760C.A more stable and weldable alloy version now called 740H was developed to meet these more demanding conditions.This paper summarizes the current status of work on alloys 740 and 740H.展开更多
Improving the unit heat efficiency,reducing coal consumption and the emission of CO_2 and meeting the requirements of environmental protection and energy conservation is the goal of the boiler and the power industry.D...Improving the unit heat efficiency,reducing coal consumption and the emission of CO_2 and meeting the requirements of environmental protection and energy conservation is the goal of the boiler and the power industry.Developments of large capacity and high parameter ultra-supercritical(USC) units are the tendency of the power industry.There is no doubt that the development of USC units is based on the development of materials, especially the materials used for super-heater and reheater in high-temperature USC boiler.Due to the long time exposure to the harsh environment,such as bearing the 600℃steam oxidation,and withstanding the corrosive flue gas and fly ash erosion,the materials require not only good high-temperature strength,but also a good corrosion resistance.In consideration of the requirements cited above,foreign countries had developed TP310HCbN (07Cr25Ni21CbN) austenitic heat-resistant steel.However,the domestic demands for this material still depend on import and the cost is high,so the boiler and the power industry expects eagerly that these steels can be produced by domestic metallurgical industry,especially Baosteel,to replace the imported products.In order to satisfy the requirements of domestic manufacturing super-heater and reheater used in ultra-supercritical power boiler,after developed T23、T91、T92、S30432 high pressure boiler tube,Baosteel began to develop TP310HCbN (07Cr25Ni21CbN)austenitic stainless steel tube in January of 2007.This study describes the composition design, the manufacturing process of product,and the assessment of performance of Baosteel's TP310HCbN (07Cr25Ni21CbN).The data indicates that properties of Baosteel's TP310HCbN(07Cr25Ni21CbN) conform to the ASME SA-213 standard and GB5310 standard,so it can substitute the imported products and is suitable for manufacturing power station boiler of great capacity and high steam parameters.展开更多
Large eddy simulation (LES) has become a promising tool for pulverized coal combustion with the development of computational fluid dynamics (CFD) technologies in recent years. LES can better capture the unsteady featu...Large eddy simulation (LES) has become a promising tool for pulverized coal combustion with the development of computational fluid dynamics (CFD) technologies in recent years. LES can better capture the unsteady features and turbulent structures of coal jet flame than Reynolds averaged Navier Stokes (RANS). The coal-fired power plants in China are now required to be operated in a wide load range and quickly respond to the electric grid. The boiler performance of variable loads should be evaluated in terms of flow, heat transfer, and combustion processes. In this paper, LES was applied to simulate a 660 MW ultra-supercritical boiler under BMCR (boiler maximum continue rate), 75%THA-100, and 50%THA-100 conditions. The predicted gas velocities agree well with the thermal calculation and the temperature error is less than 130 K. The simulation results show that the operation load has significant effects on the boiler performance. It is also proved that LES can provide guidance for the design and operation of advanced coal-fired boilers.展开更多
基金financially supported by the National Key Research&Development Program of China(2018YFB0604400)。
文摘A double reheat ultra-supercritical boiler is an important development direction for high-parameter and large-capacity coal-fired power plants due to its high thermal efficiency and environmental value.China has developed a 1000 MW double reheat ultra-supercritical boiler with steam parameters of 35 MPa at 605℃/613℃/613℃.Reasonable water wall design is one of the keys to safe and reliable operation of the boiler.In order to examine the thermal-hydraulic characteristics of the double reheat ultra-supercritical boiler,the water wall system was equivalent to a flow network comprising series-parallel circuits,linking circuits and pressure nodes,and a calculation model was built on account of the conservation equations of energy,momentum and mass.Through the iterative solving of nonlinear equations,the prediction parameters of the water wall at boiler maximum continue rate(BMCR),75%turbine heat-acceptance rate(THA)and 30%THA loads,including total pressure drops,flow distribution,outlet steam temperatures,fluid and metal temperatures were gotten.The results of calculation exhibit excellent thermal-hydraulic characteristics and substantiate the feasibility of the water wall design of the double reheat ultra-supercritical boiler.
文摘The advanced ultra-supercritical power plants of the future will utilize steam pressures and temperatures that are too high for traditional ferritic steels,thus requiring austenitic materials.Older nickel-base superalloys such as 263 and 617 were initially evaluated under the European THERMIE project beginning in the 1990s.An entirely new age-hardened alloy 740 which possesses exceptional fireside corrosion resistance and creep strength was also developed for boiler tubing capable of serving at 700C.Subsequently,interest in the USA considered other product forms such as steam header piping and steam turbine forgings for service as high as 760C.A more stable and weldable alloy version now called 740H was developed to meet these more demanding conditions.This paper summarizes the current status of work on alloys 740 and 740H.
文摘Improving the unit heat efficiency,reducing coal consumption and the emission of CO_2 and meeting the requirements of environmental protection and energy conservation is the goal of the boiler and the power industry.Developments of large capacity and high parameter ultra-supercritical(USC) units are the tendency of the power industry.There is no doubt that the development of USC units is based on the development of materials, especially the materials used for super-heater and reheater in high-temperature USC boiler.Due to the long time exposure to the harsh environment,such as bearing the 600℃steam oxidation,and withstanding the corrosive flue gas and fly ash erosion,the materials require not only good high-temperature strength,but also a good corrosion resistance.In consideration of the requirements cited above,foreign countries had developed TP310HCbN (07Cr25Ni21CbN) austenitic heat-resistant steel.However,the domestic demands for this material still depend on import and the cost is high,so the boiler and the power industry expects eagerly that these steels can be produced by domestic metallurgical industry,especially Baosteel,to replace the imported products.In order to satisfy the requirements of domestic manufacturing super-heater and reheater used in ultra-supercritical power boiler,after developed T23、T91、T92、S30432 high pressure boiler tube,Baosteel began to develop TP310HCbN (07Cr25Ni21CbN)austenitic stainless steel tube in January of 2007.This study describes the composition design, the manufacturing process of product,and the assessment of performance of Baosteel's TP310HCbN (07Cr25Ni21CbN).The data indicates that properties of Baosteel's TP310HCbN(07Cr25Ni21CbN) conform to the ASME SA-213 standard and GB5310 standard,so it can substitute the imported products and is suitable for manufacturing power station boiler of great capacity and high steam parameters.
基金This work was funded by the National Key Research and Development Program of China(No.2017YFB0602102)the National Natural Science Foundation of China(Grant No.51761125011).
文摘Large eddy simulation (LES) has become a promising tool for pulverized coal combustion with the development of computational fluid dynamics (CFD) technologies in recent years. LES can better capture the unsteady features and turbulent structures of coal jet flame than Reynolds averaged Navier Stokes (RANS). The coal-fired power plants in China are now required to be operated in a wide load range and quickly respond to the electric grid. The boiler performance of variable loads should be evaluated in terms of flow, heat transfer, and combustion processes. In this paper, LES was applied to simulate a 660 MW ultra-supercritical boiler under BMCR (boiler maximum continue rate), 75%THA-100, and 50%THA-100 conditions. The predicted gas velocities agree well with the thermal calculation and the temperature error is less than 130 K. The simulation results show that the operation load has significant effects on the boiler performance. It is also proved that LES can provide guidance for the design and operation of advanced coal-fired boilers.
