Nuclear Technology · 2003 · 263 citations · 11 references
Hydrogen Energy TechnologyHydrogen ProductionEngineeringLiquid Metal CoolingReactor DesignMolten Fluoride SaltsThermal Energy StorageNuclear Reactor DesignEngineering ThermodynamicsHydrogen GenerationChemical EngineeringThermodynamicsFusion Reactor MaterialNuclear ReactorsNuclear Reactor OperationMaterials ScienceElectrical EngineeringNuclear FuelHydrogen UtilizationHydrogen Production TechnologyHydrogenHeat TransferAdvanced Nuclear ReactorsHigh Temperature MaterialsThermal HydraulicsNuclear Reactor EngineeringPool ConfigurationMolten-salt Coolant
The molten‑salt‑cooled Advanced High‑Temperature Reactor (AHTR) is a new concept that delivers 750–1000 °C heat for efficient, low‑cost thermochemical hydrogen production or electricity generation. This paper presents an initial description and technical analysis of the AHTR’s key features. The AHTR combines coated‑particle graphite‑matrix fuel with a molten‑salt coolant in a pool configuration, enabling operation near 1400 °C at atmospheric pressure and supplying near‑constant high‑temperature, low‑pressure heat for hydrogen chemistry or a >50 % efficient multireheat helium Brayton cycle for electricity. The low‑pressure molten‑salt coolant’s high heat capacity and natural circulation provide robust, fully passive decay‑heat removal, improved economics, and the potential for high power densities and scaling to reactors >1000 MW(e).
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 production of hydrogen (H2) or production of electricity. This paper provides an initial description and technical analysis of its key features. The proposed AHTR uses coated-particle graphite-matrix fuel similar to that used in high-temperature gas-cooled reactors (HTGRs), such as the General Atomics gas turbine-modular helium reactor. However, unlike the HTGRs, the AHTR uses a molten-salt coolant and a pool configuration, similar to that of the General Electric Super Power Reactor Inherently Safe Module (S-PRISM) liquid-metal reactor. Because the boiling points for molten fluoride salts are near ~1400°C, the reactor can operate at very high temperatures and atmospheric pressure. For thermochemical H2 production, the heat is delivered at the required near-constant high temperature and low pressure. For electricity production, a multireheat helium Brayton (gas-turbine) cycle, with efficiencies >50%, is used. The low-pressure molten-salt coolant, with its high heat capacity and natural circulation heat transfer capability, creates the potential for robust safety (including fully passive decay-heat removal) and improved economics with passive safety systems that allow higher power densities and scaling to large reactor sizes [>1000 MW(electric)].
11