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Title: Sensitivity Studies of Advanced Reactors Coupled to High Temperature Electrolysis (HTE) Hydrogen Production Processes

Abstract

High Temperature Electrolysis (HTE), when coupled to an advanced nuclear reactor capable of operating at reactor outlet temperatures of 800 °C to 950 °C, has the potential to efficiently produce the large quantities of hydrogen needed to meet future energy and transportation needs. To evaluate the potential benefits of nuclear-driven hydrogen production, the UniSim process analysis software was used to evaluate different reactor concepts coupled to a reference HTE process design concept. The reference HTE concept included an Intermediate Heat Exchanger and intermediate helium loop to separate the reactor primary system from the HTE process loops and additional heat exchangers to transfer reactor heat from the intermediate loop to the HTE process loops. The two process loops consisted of the water/steam loop feeding the cathode side of a HTE electrolysis stack, and the steam or air sweep loop used to remove oxygen from the anode side. The UniSim model of the process loops included pumps to circulate the working fluids and heat exchangers to recover heat from the oxygen and hydrogen product streams to improve the overall hydrogen production efficiencies. The reference HTE process loop model was coupled to separate UniSim models developed for three different advanced reactor concepts (amore » high-temperature helium cooled reactor concept and two different supercritical CO2 reactor concepts). Sensitivity studies were then performed to evaluate the affect of reactor outlet temperature on the power cycle efficiency and overall hydrogen production efficiency for each of the reactor power cycles. The results of these sensitivity studies showed that overall power cycle and hydrogen production efficiencies increased with reactor outlet temperature, but the power cycle producing the highest efficiencies varied depending on the temperature range considered.« less

Authors:
; ; ;
Publication Date:
Research Org.:
Idaho National Laboratory (INL)
Sponsoring Org.:
DOE - NE
OSTI Identifier:
911926
Report Number(s):
INL/CON-07-12065
TRN: US0800217
DOE Contract Number:
DE-AC07-99ID-13727
Resource Type:
Conference
Resource Relation:
Conference: International Conference on Nuclear Engineering 15 (ICONE15),Nagoya, Japan,04/22/2007,04/26/2007
Country of Publication:
United States
Language:
English
Subject:
08 - HYDROGEN; ANODES; CATHODES; DESIGN; EFFICIENCY; ELECTROLYSIS; FEEDING; HEAT EXCHANGERS; HELIUM; HELIUM COOLED REACTORS; HYDROGEN; HYDROGEN PRODUCTION; NUCLEAR ENGINEERING; OXYGEN; REACTORS; SENSITIVITY; STEAM; WORKING FLUIDS; advanced nuclear reactor; hydrogen; outlet temperature

Citation Formats

Edwin A. Harvego, Michael G. McKellar, James E. O'Brien, and J. Stephen Herring. Sensitivity Studies of Advanced Reactors Coupled to High Temperature Electrolysis (HTE) Hydrogen Production Processes. United States: N. p., 2007. Web.
Edwin A. Harvego, Michael G. McKellar, James E. O'Brien, & J. Stephen Herring. Sensitivity Studies of Advanced Reactors Coupled to High Temperature Electrolysis (HTE) Hydrogen Production Processes. United States.
Edwin A. Harvego, Michael G. McKellar, James E. O'Brien, and J. Stephen Herring. 2007. "Sensitivity Studies of Advanced Reactors Coupled to High Temperature Electrolysis (HTE) Hydrogen Production Processes". United States. doi:. https://www.osti.gov/servlets/purl/911926.
@article{osti_911926,
title = {Sensitivity Studies of Advanced Reactors Coupled to High Temperature Electrolysis (HTE) Hydrogen Production Processes},
author = {Edwin A. Harvego and Michael G. McKellar and James E. O'Brien and J. Stephen Herring},
abstractNote = {High Temperature Electrolysis (HTE), when coupled to an advanced nuclear reactor capable of operating at reactor outlet temperatures of 800 °C to 950 °C, has the potential to efficiently produce the large quantities of hydrogen needed to meet future energy and transportation needs. To evaluate the potential benefits of nuclear-driven hydrogen production, the UniSim process analysis software was used to evaluate different reactor concepts coupled to a reference HTE process design concept. The reference HTE concept included an Intermediate Heat Exchanger and intermediate helium loop to separate the reactor primary system from the HTE process loops and additional heat exchangers to transfer reactor heat from the intermediate loop to the HTE process loops. The two process loops consisted of the water/steam loop feeding the cathode side of a HTE electrolysis stack, and the steam or air sweep loop used to remove oxygen from the anode side. The UniSim model of the process loops included pumps to circulate the working fluids and heat exchangers to recover heat from the oxygen and hydrogen product streams to improve the overall hydrogen production efficiencies. The reference HTE process loop model was coupled to separate UniSim models developed for three different advanced reactor concepts (a high-temperature helium cooled reactor concept and two different supercritical CO2 reactor concepts). Sensitivity studies were then performed to evaluate the affect of reactor outlet temperature on the power cycle efficiency and overall hydrogen production efficiency for each of the reactor power cycles. The results of these sensitivity studies showed that overall power cycle and hydrogen production efficiencies increased with reactor outlet temperature, but the power cycle producing the highest efficiencies varied depending on the temperature range considered.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2007,
month = 4
}

Conference:
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  • An initial study was conducted on a fusion reactor and high temperature electrolyzer system for the production of synthetic fuel. The design temperatures in the fusion reactor blanket were above 1380/sup 0/C. Electrolytic hydrogen production at the high temperatures consumes a high ratio of thermal to electric energy and increases the efficiency of the plant and an overall efficiency of approximately 50% appeared possible. The concepts of the system and the design considerations of the high temperature electrolyzer will be presented.
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