Power transmission across the sea is an important part of global energy interconnection(GEI).To support the construction of GEI and to serve the needs of future clean energy trans-sea transportation and offshore wind ...Power transmission across the sea is an important part of global energy interconnection(GEI).To support the construction of GEI and to serve the needs of future clean energy trans-sea transportation and offshore wind power development,this study a)analyzes the requirements of the GEI backbone network pertaining to direct current(DC)submarine cable technology,and b)defines the key technical and economic indices of ultrahigh-voltage direct current(UHVDC)submarine cable based on theoretical computations.The research is based on the thermoelectric coupling model and the finite element method.It is shown that the dielectric strength of the insulating materials of the±800 kV~±1100 kV/4000 MW^12000 MW UHVDC submarine cable(extrusion insulation)should be not less than 43~65 kV/mm,while the heat resistance is not less than 110°C.As the cost of submarine cable is 5~10 times higher than that of the overhead line,the project investment need to be decreased to a level within the economical carrying capacity to guarantee extensive applicability of the HVDC submarine cable technology.展开更多
According to the composition of rare earth ores and the market, several feasible separation processes of bastnasite in Baotou of Inner Mongolia and Mianning of Sichuan by solvent extraction in HEH(EHP) HCl system wer...According to the composition of rare earth ores and the market, several feasible separation processes of bastnasite in Baotou of Inner Mongolia and Mianning of Sichuan by solvent extraction in HEH(EHP) HCl system were presented. The parameters of the processes such as stage numbers, volume of mixer settler, fixed investment of extractant and rare earths, consumption of chemical reagents including HCl and NH 3 were calculated and compared. The results show that the novel scheme can save cost more than 20% compared with those of others. By the economical analysis, the optimized separation process of bastnasite was obtained, which can be applied to the treatment of monazite too.展开更多
The line pipes with large diameter,thick wall and high steel grade are preferred to meet the requirements of extremely high gas transmission rate(380×10^(8) m^(3)/a)in the Sino-Russian eastern route project.In th...The line pipes with large diameter,thick wall and high steel grade are preferred to meet the requirements of extremely high gas transmission rate(380×10^(8) m^(3)/a)in the Sino-Russian eastern route project.In this paper,the technical standards of line pipes at home and abroad were comparatively analyzed after the research and formulation process of technical specifications of X80 line pipes(OD 1422 mm)used in the above-mentioned project was introduced.The key technical indexes such as chemical components,crack-arrest-toughness values,etc.and its formulation process were discussed.In addition,the development process and product performance of the X80 line pipes(OD 1422 mm)were described.It is proved by trial production and product tests that using X80 line pipes(OD 1422 mm)in this gas project is a rational and effective solution to the following technical issues such as chemical composition control,fracture control and welding stability maintenance.This type of line pipes is proved not only to meet project requirements,but to suit for production cases.As a result,the safety of Sino-Russian eastern route gas pipeline will be guaranteed essentially.The research results in this paper provide a strong technical support for the application of X80 line pipes(OD 1422 mm)in the Sino-Russian eastern route project,and play a guiding role in drawing up the technical specifications of other gas pipeline projects.展开更多
The occupant behavior is a primary factor contributing to the gap between the designed and actual building energy performance.The current design concepts and methods of ultra-low energy housing(ULEH)in hot summer and ...The occupant behavior is a primary factor contributing to the gap between the designed and actual building energy performance.The current design concepts and methods of ultra-low energy housing(ULEH)in hot summer and cold winter climate zones of China(HSCW)still follow the continuous energy use pattern,rather than the actual“part space,part-time”environmental control behavior adopted by residents in the region.This leads to large discrepancies between the actual and expected performance,coupled with the issue of high incremental costs due to the employment of high technologies,resulting in the slow promotion of ULEH in the region.This research selects Changsha,a typical city in the region,to establish a numerical model of the actual occupant behavior.Based on the model,an improved orthogonal experimental method is employed to examine the impact from energy-saving technologies on building energy and economic performances,so as to identify the key variables.The schemes achieving ULEH are then obtained through parametric analysis.Finally,the technical index system of ultra-low energy housing is reconstructed based on a comprehensive analysis of the schemes.It is found the global cost increment(GCI)of the schemes is 169 yuan/m^(2)cheaper than that of the reference building,and 202–794 yuan/m^(2)cheaper compared with the current standard of ULEH.This study contributes to minimize the performance gap and improve the affordability of ultra-low energy housing,so as to promote its replication in the region.展开更多
基金supported by the Global Energy Interconnection Group Co.,Ltd.Science and Technology Project(Project No.101662224/Title:UHV large-capacity DC submarine cable key technology and roadmap research)the National Key R&D Program of China(2016YFB0900702)
文摘Power transmission across the sea is an important part of global energy interconnection(GEI).To support the construction of GEI and to serve the needs of future clean energy trans-sea transportation and offshore wind power development,this study a)analyzes the requirements of the GEI backbone network pertaining to direct current(DC)submarine cable technology,and b)defines the key technical and economic indices of ultrahigh-voltage direct current(UHVDC)submarine cable based on theoretical computations.The research is based on the thermoelectric coupling model and the finite element method.It is shown that the dielectric strength of the insulating materials of the±800 kV~±1100 kV/4000 MW^12000 MW UHVDC submarine cable(extrusion insulation)should be not less than 43~65 kV/mm,while the heat resistance is not less than 110°C.As the cost of submarine cable is 5~10 times higher than that of the overhead line,the project investment need to be decreased to a level within the economical carrying capacity to guarantee extensive applicability of the HVDC submarine cable technology.
文摘According to the composition of rare earth ores and the market, several feasible separation processes of bastnasite in Baotou of Inner Mongolia and Mianning of Sichuan by solvent extraction in HEH(EHP) HCl system were presented. The parameters of the processes such as stage numbers, volume of mixer settler, fixed investment of extractant and rare earths, consumption of chemical reagents including HCl and NH 3 were calculated and compared. The results show that the novel scheme can save cost more than 20% compared with those of others. By the economical analysis, the optimized separation process of bastnasite was obtained, which can be applied to the treatment of monazite too.
文摘The line pipes with large diameter,thick wall and high steel grade are preferred to meet the requirements of extremely high gas transmission rate(380×10^(8) m^(3)/a)in the Sino-Russian eastern route project.In this paper,the technical standards of line pipes at home and abroad were comparatively analyzed after the research and formulation process of technical specifications of X80 line pipes(OD 1422 mm)used in the above-mentioned project was introduced.The key technical indexes such as chemical components,crack-arrest-toughness values,etc.and its formulation process were discussed.In addition,the development process and product performance of the X80 line pipes(OD 1422 mm)were described.It is proved by trial production and product tests that using X80 line pipes(OD 1422 mm)in this gas project is a rational and effective solution to the following technical issues such as chemical composition control,fracture control and welding stability maintenance.This type of line pipes is proved not only to meet project requirements,but to suit for production cases.As a result,the safety of Sino-Russian eastern route gas pipeline will be guaranteed essentially.The research results in this paper provide a strong technical support for the application of X80 line pipes(OD 1422 mm)in the Sino-Russian eastern route project,and play a guiding role in drawing up the technical specifications of other gas pipeline projects.
基金financially supported by the China Science and Technology Exchange Center(2023YFE0106700)the Department of Science and Technology of Hunan Province China(No.2022JJ30140).
文摘The occupant behavior is a primary factor contributing to the gap between the designed and actual building energy performance.The current design concepts and methods of ultra-low energy housing(ULEH)in hot summer and cold winter climate zones of China(HSCW)still follow the continuous energy use pattern,rather than the actual“part space,part-time”environmental control behavior adopted by residents in the region.This leads to large discrepancies between the actual and expected performance,coupled with the issue of high incremental costs due to the employment of high technologies,resulting in the slow promotion of ULEH in the region.This research selects Changsha,a typical city in the region,to establish a numerical model of the actual occupant behavior.Based on the model,an improved orthogonal experimental method is employed to examine the impact from energy-saving technologies on building energy and economic performances,so as to identify the key variables.The schemes achieving ULEH are then obtained through parametric analysis.Finally,the technical index system of ultra-low energy housing is reconstructed based on a comprehensive analysis of the schemes.It is found the global cost increment(GCI)of the schemes is 169 yuan/m^(2)cheaper than that of the reference building,and 202–794 yuan/m^(2)cheaper compared with the current standard of ULEH.This study contributes to minimize the performance gap and improve the affordability of ultra-low energy housing,so as to promote its replication in the region.
