The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Rui Yan - One of the best experts on this subject based on the ideXlab platform.
-
Preferred core conceptual design of pebble bed advanced high Temperature Reactor
Annals of Nuclear Energy, 2021Co-Authors: Lianjie Wang, Yang Zou, Sun Wei, Bangyang Xia, Rui YanAbstract:Abstract Key parameters of Pebble Bed Advanced High Temperature Reactor (PB-AHTR) core are studied, and then the preferred core conceptual design is proposed. Both evacuating molten salt and injecting poison into coolant can be used as the auxiliary system of the second shutdown system in PB-AHTR. Compared with injecting poison into coolant, the effect of evacuating molten salt on the core is smaller and more beneficial to the engineering realization. Compared to one-time loading scheme, batch loading scheme can ensure that a small core excess reactivity in whole life-time which is easier to be controlled, but more complex to operation. In one-time loading scheme, the second shutdown system gains enough fast shutdown margins by increasing the number of second control rod, instead of reducing the stack height of core activity. The shutdown margins of both the first shutdown system and the second shutdown system meet the design requirements.
-
thorium utilization with pebble mixing system in fluoride salt cooled high Temperature Reactor
Progress in Nuclear Energy, 2019Co-Authors: Guifeng Zhu, Rui Yan, Yang Zou, Sijia Liu, Menglu Tan, Xuzong Kang, Bo Zhou, Ye DaiAbstract:Abstract Mixing system of uranium pebbles and thorium pebbles is compared with thorium blanket system to utilize thorium in Pebble Bed Fluoride Salt-cooled High Temperature Reactor (PB-FHR). A random modeling method is introduced to simulate the pebble mixing system. Cases with different volume fractions of uranium pebbles are researched to find the optimal utilization of uranium and the lower power nonuniformity. It indicates that using thorium in pebble mixing system with 80 vol% uranium pebbles can improve uranium utilization by 10%, while in thorium blanket system it can be increased by 20%. The radial power peak factor in pebble mixing system is about 1.48 while in thorium blanket system is about 1.83. In-pile residence time of thorium pebbles in pebble mixing system is only 4.7 year, while in thorium blanket system is 9 year. Thorium utilization with pebble mixing system in PB-FHR shows a little lower fuel utilization but higher safety and technical feasibility.
-
uranium utilization with thorium blanket in pebble bed fluoride salt cooled high Temperature Reactor
Progress in Nuclear Energy, 2015Co-Authors: Guifeng Zhu, Ye Dai, Yang Zou, Rui YanAbstract:Thorium blanket fuel is investigated in Pebble Bed Fluoride salt-cooled High Temperature Reactor (PB-FHR) with 19.9 at% U-235 seed fuel to improve the utilization of uranium fuel. Uranium fuel utilization is optimized with lots of parameters, such as graphite-to-thorium atom ratio (C/Th), graphite-to-uranium atom ratio (C/U), discharge burnup of thorium and uranium, and the dimension of the seed/blanket region. It is found that the equivalent discharge burnup, defined as total released energy over the mass of uranium, could be improved to around 265 MWd/kgU, which is 20% higher than discharge burnup using pure uranium fuel. In equilibrium state, the Temperature reactivity coefficients of fuel and coolant are both negative. Other properties such as radial power peak factor, life of reflector, in-pile residence time of thorium pebble and radioactive waste are analyzed. Finally, baseline design parameters are recommended for further thermal-hydraulic analysis and TRISO fuel performance. (C) 2015 Elsevier Ltd. All rights reserved.
Ye Dai - One of the best experts on this subject based on the ideXlab platform.
-
thorium utilization with pebble mixing system in fluoride salt cooled high Temperature Reactor
Progress in Nuclear Energy, 2019Co-Authors: Guifeng Zhu, Rui Yan, Yang Zou, Sijia Liu, Menglu Tan, Xuzong Kang, Bo Zhou, Ye DaiAbstract:Abstract Mixing system of uranium pebbles and thorium pebbles is compared with thorium blanket system to utilize thorium in Pebble Bed Fluoride Salt-cooled High Temperature Reactor (PB-FHR). A random modeling method is introduced to simulate the pebble mixing system. Cases with different volume fractions of uranium pebbles are researched to find the optimal utilization of uranium and the lower power nonuniformity. It indicates that using thorium in pebble mixing system with 80 vol% uranium pebbles can improve uranium utilization by 10%, while in thorium blanket system it can be increased by 20%. The radial power peak factor in pebble mixing system is about 1.48 while in thorium blanket system is about 1.83. In-pile residence time of thorium pebbles in pebble mixing system is only 4.7 year, while in thorium blanket system is 9 year. Thorium utilization with pebble mixing system in PB-FHR shows a little lower fuel utilization but higher safety and technical feasibility.
-
uranium utilization with thorium blanket in pebble bed fluoride salt cooled high Temperature Reactor
Progress in Nuclear Energy, 2015Co-Authors: Guifeng Zhu, Ye Dai, Yang Zou, Rui YanAbstract:Thorium blanket fuel is investigated in Pebble Bed Fluoride salt-cooled High Temperature Reactor (PB-FHR) with 19.9 at% U-235 seed fuel to improve the utilization of uranium fuel. Uranium fuel utilization is optimized with lots of parameters, such as graphite-to-thorium atom ratio (C/Th), graphite-to-uranium atom ratio (C/U), discharge burnup of thorium and uranium, and the dimension of the seed/blanket region. It is found that the equivalent discharge burnup, defined as total released energy over the mass of uranium, could be improved to around 265 MWd/kgU, which is 20% higher than discharge burnup using pure uranium fuel. In equilibrium state, the Temperature reactivity coefficients of fuel and coolant are both negative. Other properties such as radial power peak factor, life of reflector, in-pile residence time of thorium pebble and radioactive waste are analyzed. Finally, baseline design parameters are recommended for further thermal-hydraulic analysis and TRISO fuel performance. (C) 2015 Elsevier Ltd. All rights reserved.
Guifeng Zhu - One of the best experts on this subject based on the ideXlab platform.
-
thorium utilization with pebble mixing system in fluoride salt cooled high Temperature Reactor
Progress in Nuclear Energy, 2019Co-Authors: Guifeng Zhu, Rui Yan, Yang Zou, Sijia Liu, Menglu Tan, Xuzong Kang, Bo Zhou, Ye DaiAbstract:Abstract Mixing system of uranium pebbles and thorium pebbles is compared with thorium blanket system to utilize thorium in Pebble Bed Fluoride Salt-cooled High Temperature Reactor (PB-FHR). A random modeling method is introduced to simulate the pebble mixing system. Cases with different volume fractions of uranium pebbles are researched to find the optimal utilization of uranium and the lower power nonuniformity. It indicates that using thorium in pebble mixing system with 80 vol% uranium pebbles can improve uranium utilization by 10%, while in thorium blanket system it can be increased by 20%. The radial power peak factor in pebble mixing system is about 1.48 while in thorium blanket system is about 1.83. In-pile residence time of thorium pebbles in pebble mixing system is only 4.7 year, while in thorium blanket system is 9 year. Thorium utilization with pebble mixing system in PB-FHR shows a little lower fuel utilization but higher safety and technical feasibility.
-
uranium utilization with thorium blanket in pebble bed fluoride salt cooled high Temperature Reactor
Progress in Nuclear Energy, 2015Co-Authors: Guifeng Zhu, Ye Dai, Yang Zou, Rui YanAbstract:Thorium blanket fuel is investigated in Pebble Bed Fluoride salt-cooled High Temperature Reactor (PB-FHR) with 19.9 at% U-235 seed fuel to improve the utilization of uranium fuel. Uranium fuel utilization is optimized with lots of parameters, such as graphite-to-thorium atom ratio (C/Th), graphite-to-uranium atom ratio (C/U), discharge burnup of thorium and uranium, and the dimension of the seed/blanket region. It is found that the equivalent discharge burnup, defined as total released energy over the mass of uranium, could be improved to around 265 MWd/kgU, which is 20% higher than discharge burnup using pure uranium fuel. In equilibrium state, the Temperature reactivity coefficients of fuel and coolant are both negative. Other properties such as radial power peak factor, life of reflector, in-pile residence time of thorium pebble and radioactive waste are analyzed. Finally, baseline design parameters are recommended for further thermal-hydraulic analysis and TRISO fuel performance. (C) 2015 Elsevier Ltd. All rights reserved.
Charles W Forsberg - One of the best experts on this subject based on the ideXlab platform.
-
the advanced high Temperature Reactor high Temperature fuel liquid salt coolant liquid metal Reactor plant
Progress in Nuclear Energy, 2005Co-Authors: Charles W ForsbergAbstract:The Advanced High-Temperature Reactor is a new Reactor concept that combines four existing technologies in a new way: (1) coated-particle graphite-matrix nuclear fuels (traditionally used for helium-cooled Reactors), (2) Brayton power cycles, (3) passive safety systems and plant designs from liquid-metal-cooled fast Reactors, and (4) low-pressure liquid-salt coolants with boiling points far above the maximum coolant Temperature. The new combination of technologies enables the design of a large [2400- to 4000-MW(t)] high-Temperature Reactor, with Reactor-coolant exit Temperatures between 700 and 1000°C (depending upon goals) and passive safety systems for economic production of electricity or hydrogen. The AHTR [2400-MW(t)] capital costs have been estimated to be 49 to 61% per kilowatt (electric) relative to modular gas-cooled [600-MW(t)] and modular liquid-metal-cooled Reactors [1000-MW(t)], assuming a single AHTR and multiple modular units with the same total electrical output. Because of the similar fuel, core design, and power cycles, about 70% of the required research is shared with that for high-Temperature gas-cooled Reactors.
-
an advanced molten salt Reactor using high Temperature Reactor technology
2004Co-Authors: Charles W Forsberg, Per F Peterson, Haihua ZhaoAbstract:Molten salt Reactors (MSRs) are liquid-fueled Reactors that can be used for burning actinides, producing electricity, producing hydrogen, and producing fissile fuels (breeding). Fissile, fertile, and fission products are dissolved in a high-Temperature, molten fluoride salt with a very high boiling Temperature (~1400oC). Two Reactors were successfully built and operated in the 1950s and 1960s. A detailed conceptual design of a 1000 MW(e) Reactor was developed. There is renewed interest in MSRs because of changing goals and new technologies. Three technologies, partly or fully developed since the 1970s, have been identified that may dramatically improve the economics and viability of MSRs: Brayton helium power cycles, compact heat exchangers, and carbonBcarbon composites. All three technologies are being developed for high-Temperature Reactors. This paper describes how each of these technologies may remove major technical challenges, improve the performance, expand the potential missions, and improve the fundamental economics of the MSR. The new technologies become the enabling technologies for an Advanced Molten Salt Reactor (AMSR).
-
molten salt cooled advanced high Temperature Reactor for production of hydrogen and electricity
Nuclear Technology, 2003Co-Authors: Charles W Forsberg, Per F Peterson, Paul S PickardAbstract:The molten-salt-cooled Advanced High-Temperature Reactor (AHTR) is a new Reactor concept designed to provide very high-Temperature (750 to 1000°C) heat to enable efficient low-cost thermochemical p...
-
hydrogen nuclear energy and the advanced high Temperature Reactor
International Journal of Hydrogen Energy, 2003Co-Authors: Charles W ForsbergAbstract:Abstract Nuclear energy has been proposed as an energy source to produce hydrogen (H2) from water. An examination of systems issues in this paper indicates that the infrastructure of H2 consumption is now compatible with the production of H2 by nuclear Reactors. Alternative H2 production processes were examined to define the requirements such processes would impose on the nuclear Reactor. These requirements include supplying heat at a near-constant high Temperature, providing a low-pressure interface with the H2 production processes, isolating the nuclear plant from the chemical plant, and avoiding tritium contamination of the H2 product. A Reactor concept—the advanced high-Temperature Reactor—was developed to match these requirements for H2 production.
-
advanced high Temperature Reactor for production of electricity and hydrogen molten salt coolant graphite coated particle fuel
Other Information: PBD: 21 Feb 2002, 2002Co-Authors: Charles W ForsbergAbstract:The objective of the Advanced High-Temperature Reactor (AHTR) is to provide the very high Temperatures necessary to enable low-cost (1) efficient thermochemical production of hydrogen and (2) efficient production of electricity. The proposed AHTR uses coated-particle graphite fuel similar to the fuel used in modular high-Temperature gas-cooled Reactors (MHTGRs), such as the General Atomics gas turbine-modular helium Reactor (GT-MHR). However, unlike the MHTGRs, the AHTR uses a molten salt coolant with a pool configuration, similar to that of the PRISM liquid metal Reactor. A multi-reheat helium Brayton (gas-turbine) cycle, with efficiencies >50%, is used to produce electricity. This approach (1) minimizes requirements for new technology development and (2) results in an advanced Reactor concept that operates at essentially ambient pressures and at very high Temperatures. The low-pressure molten-salt coolant, with its high heat capacity and natural circulation heat transfer capability, creates the potential for (1) exceptionally robust safety (including passive decay-heat removal) and (2) allows scaling to large Reactor sizes [{approx}1000 Mw(e)] with passive safety systems to provide the potential for improved economics.
Natalia Howaniec - One of the best experts on this subject based on the ideXlab platform.
-
co gasification of coal sewage sludge blends to hydrogen rich gas with the application of simulated high Temperature Reactor excess heat
International Journal of Hydrogen Energy, 2016Co-Authors: Adam Smolinski, Natalia HowaniecAbstract:Abstract The experimental study on oxygen and steam gasification and co-gasification of hard coal and sewage sludge to hydrogen-rich gas was performed in the laboratory scale fixed bed gasifier equipped with an auxiliary gasification agents pre-heating system, simulating the utilization of an excess High Temperature Reactor (HTR) heat. The allothermal gasification and co-gasification tests were performed on fuel blends of coal and sewage sludge of the total mass of 10 g and biowaste content of 20% and 40%w/w in three system configurations. In the first one the Reactor was heated up with a resistance furnace to the Temperature of 700 °C in the inert gas (nitrogen) atmosphere. When the Temperature inside the Reactor was stable, oxygen and steam of the Temperature of approximately 100 °C were introduced into the Reactor. In the second system, after the Reactor was heated up to 700 °C, the heating of the Reactor was switched off and oxygen and steam were pre-heated to the Temperature of 700 °C and fed into the Reactor. In the third system a fuel sample in the Reactor was heated to the Temperature 700 °C and the set Temperature was maintained with the resistance furnace. The results showed that sufficient thermal energy required for an effective oxygen/steam gasification process was generated in systems with the external heating of the Reactor. The highest hydrogen contents in gas were reported in coal gasification, irrespective of the system configuration. The total hydrogen volume decreased with increasing biomass content in a fuel blend in all studied system configurations.
-
experimental study on application of high Temperature Reactor excess heat in the process of coal and biomass co gasification to hydrogen rich gas
Energy, 2015Co-Authors: Natalia Howaniec, Adam Smolinski, Magdalena CempabalewiczAbstract:The paper presents the results of the experimental study on the simulated application of HTR (High Temperature Reactor) excess heat in the process of allothermal co-gasification of coal and biomass. The laboratory scale installation with a fixed bed gasifier and auxiliary gasification agents pre-heating system, simulating the utilization of the HTR excess heat, were applied in the study. Steam and oxygen were the gasification media employed, and the process was focused on hydrogen-rich gas production. The results of the co-gasification of fuel blends of various biomass content at 800 °C and in various system configurations proved that the application of the simulated HTR excess heat in pre-heating of the gasification agents leads to the increase in the gaseous product yield. Furthermore, the HCA (Hierarchical Clustering Analysis) employed in the experimental data analysis revealed that the gasification of fuel blends of 20 and 40%w/w of biomass content results in higher volumes of the total gas, hydrogen, carbon monoxide and carbon dioxide than gasification of fuel blends of higher biomass content.
