2 edition of In-pile steam oxidation of model HTGR fuel elements found in the catalog.
In-pile steam oxidation of model HTGR fuel elements
S. H. Freid
by Dept. of Energy, Oak Ridge National Laboratory, for sale by the National Technical Information Service] in Oak Ridge, Tenn, [Springfield, Va
Written in English
|Statement||S. H. Freid, Bechtel Corporation, H. J. de Nordwall, Commission of the European Communities, A. P. Malinauskas.|
|Series||ORNL/TM ; 6399, ORNL/TM -- 6399.|
|Contributions||Nordwall, H. J. de., Malinauskas, A. P., Bechtel Corporation., Commission of the European Communities., Oak Ridge National Laboratory.|
|The Physical Object|
|Pagination||iii, 59 p. :|
|Number of Pages||59|
A task to examine the most recent NRC fuel-failure model (NUREG) in light of current data from FSV and other experiments is being considered for Primary Coolant Impurities The Los Alamos research in Primary Coolant Impurities was divided between code development and study of impurity reactions with graphite and metallic components. Abstract. The fuel element matrix graphites A and A were used in High Temperature Reactor fuel pebbles for many years. However, these materials show as other graphites a limited oxidation resistance in contact to oxidising gases (air and steam), which even decreases with increasing temperatures: In HTRs, having in normal operation a non-oxidising environment, an ingress of air or steam.
The process is, typically, much faster than steam reforming and requires a smaller reactor vessel. As can be seen in chemical reactions of partial oxidation, this process initially produces less hydrogen per unit of the input fuel than is obtained by steam reforming of the same fuel. Partial oxidation of methane reaction CH 4 + ½O 2 → CO. tion products somewhat. Fuel sulfur is usually oxidized to form sulfur dioxide (), (Even though there are cases where sulfur compounds involving higher oxidation states ofsulfur or reduced sulfur compounds are produced, it is a reasonable first approxima tion to assume that all of the fuel sulfur forms ,) Upon combustion, organically.
The gasification of liquid and gaseous feedstocks, like oil and natural gas, was developed by Texaco and Shell in the lates/earlys according to Higman (). These companies have been in the market ever since with entrained-flow, refractory-lined reactors, top-mounted downflow burners and operation temperatures around 1,,°C. Presently, the most important test methods for the oxidation stability testing of petrodiesel are ISO 12 and ASTM D These methods require a hr-long aging process at 95 °C under oxygen flow. The fuel is subsequently filtered and the vessel cleaned in order to collect the entire amount of residue created during the test for weighing.
Franchising in Australia
Central Public Health Laboratory
United States government master specification for rubber-metal gasoline hose.
Efforts towards the synthesis of homochiral tin hydrides.
In the heart of the Rockies
Thames Water statistics.
In the American jungle
New York State Thruway Authority, proposed Sterling Forest interchange
State of Rhode Island and Providence Plantations. In General Assembly, July second session, 1780.
Souvenir [of the] Jubilee 1869-1919 [of the] Durham Miners Association
Operating system concepts
The visibility and comprehension of pedestrian traffic signals
Development of some travel demand models.
Get this from a library. In-pile steam oxidation of model HTGR fuel elements. [S H Freid; H J de Nordwall; A P Malinauskas; Bechtel Corporation.; Commission of the European Communities.; Oak Ridge National Laboratory.]. The fuel assemblies at the core bottom are subjected to the most severe oxidation conditions.
Description of HTGR and oxidation conditions Description of HTGR. In the studied block-type HTGR, fuel assemblies are hexagonal prismatic graphite blocks with a ‘flat-to-flat’ size of mm and a height of by: The modeling of graphite oxidation behavior for HTGR fuel coolant channels under normal operating conditions matrix of the spherical fuel elements by steam in normal operating conditions.
Since the CO and CO 2 result almost entirely from graphite corrosion, then the measured CO and CO 2 concentrations may be used to estimate the loss in graphite mass as a function of time.
For the thermodynamic conditions in the Petten reactor, the likely reaction for graphite corrosion is given by (1) C + H 2 O → C O + H The water–gas–shift reaction will convert some CO to CO 2, : M.B.
Richards, A.G. Gillespie, D.L. Hanson. From this point of view, we investigated the conceptual design of commercial HTGR for early introduction to provide steam for industrial heat utilization based on the cumulated experience of a design, construction, and operation of High Temperature engineering Test Reactor (HTTR) (Saito et al., ), whose power output is 30 MWt, and a design Cited by: 1.
The T22 steel with ∼ wt% Cr under steam oxidation shows the formation of three oxides at high temperature. The presented results indicate the formation of thick oxide scales consisting Fe 2 O 3 (hematite), Fe 3 O 4, (magnetite), and FeO (wustite).
The formation of all three oxides is expected under steam oxidation conditions. Oxidation of SiC coating layer of TRISO fuel particles in high-temperature (– °C) flowing steam environments was examined for up to 24 h. The CVD-SiC coating layer exhibits very good steam oxidation resistance where no thickness loss beyond μm was observed up to 24 h under these conditions.
Full core behavior was studied with a 1/5-scale model of a MW(t) HTGR core (ref. The model included more than graphite elements representing fuel elements, reflector elements, and core support blocks (Fig.
These tests were limited to separate uniaxial input across the flats of the hexagonal fuel elements and across the corners. Diffusion from the fuel compact or graphite block to the coolant Fuel loading scheme Temperature maps Finite difference code description Results HTGR FUEL CYCLES Introduction An assessment of HTGR fuel cycle flexibilities A review of possible HTGR fuel cycles The oxidation model can obtain correct cumulative hydrogen production.
As we all know, the behaviors of fuel elements during reflood are extremely complicated. The analysis program cannot completely reflect the complicated physical and chemical process in details. Simulated oxidation resistant fuel elements with matrix whose Si/C mole ratio is were fabricated.
Failure fraction of CFPs in fuel elements is one of very important inspection subjects of HTGR fuel. It is essential that CFPs are extracted from fuel elements without additional failure.
Development of method for extraction of CFPs was. Steam oxidation of silicon carbide (SiC) layer in nuclear fuel particles were performed in flowing argon-water vapor mixture with a total pressure of 1 bar at K.
This work is devoted to spherical fuel elements for the high temperature pebble bed reactor, their manufacture and the conditions which they must satisfy for use in a process-heat reactor with an. Enhancement of safety and cooling performance of fuel elements are desired for a commercial High Temperature Gas-cooled Reactor (HTGR).
Applying sleeveless fuel elements and dual side directly cooling structures with oxidation resistant SiC-matrix fuel compact has a possibility of improving safety and cooling performance at the pin-in-block. Performance of the tubular fuel elements of the French natural uranium, graphite moderated gas-cooled reactors.
B Fission product retention characteristics of HTGR fuel. Burnette, carried out by BELGONUCLEAIRE and CEA on the improvement and verification of the COMETHE computer code with the aid of in-pile experimental results.
The steam generator is one of the main components in HTGR as well as in RDE. In the steam generator, the heat is transferred by high temperature helium gas in the shell side to water in the tube. These are activities plated out on metal components, dust-borne activities and particles with defect coatings.
In-pile experiments on plate-out and on dust behaviour are proposed in order to improve knowledge in these fields.
Irradiation tests of HTGR fuel under normal and accident conditions (presented by A. Chernikov, Lutch, Russia). Thermodynamic assessments of SiC in low partial pressures of steam indicate that at atm steam in a temperature range from °C the pO 2 in steam is sufficient to observe both passive and active oxidation, with the transition occurring between °C.
Additionally, at atm steam, the pO. 3 Why Hydrogen. H 2 + ½ O 2 →H 2O ∆H kcal/mole zH 2 is an energy vector, is converted to water which has minimal environmental impact. zH 2 is a non-polluting fuel for transportation vehicles and power production zCurrently road vehicles emit about the same quantity of CO 2 as power production.
zH 2 can be produced from fossil fuels with CO 2 capture and storage or from renewables. Currently, several oxidation stability test methods (eg. ENISO, Rancimat (EN), PetroOXY (EN)) are used for this purpose. It is common for these tests to have an elevated temperature and to add oxygen or air to accelerate the oxidation of the test fuel.
Abstract. Chapter 2 gives the methods for describing steady and transient temperature fields in the fuel elements. Some information is provided regarding influence of the cladding oxidation, hydrogen diffusion, and corrosion product deposition on the temperature fields.Graphite components in HTGR and VHTR may be oxidized by impurities in coolant helium-gas even at normal operation, as well as by air at air-ingress accident.
In this study, by air-oxidation test at C, oxidation characteristics of IG and IG graphites, and associated decrease in compressive strength were examined. The following.Occupational radiation exposures in high-temperature gas-cooled reactor (HTGR) plants were assessed.
The expected rate of dose accumulations for a large HTGR steam cycle (HTGR-SC) unit is man-rem/MW(e)y, while the design basis is man-rem/MW(e)y. The comparable figure for actual light water reactor (LWR) experience is man-rem/MW(e)y.