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Morgan, Gregg A.

Publications and source records attributed to Morgan, Gregg A..

Evaluation of a cleaning method for the tritium environment

Solvents can be used to clean process equipment and piping that will come in contact with tritium containing gas streams; but, the ways in which solvents interact with catalysts is also of interest. This method of cleaning does not account for impurities within the bulk of a material that could be released from catalyst or containment barriers during high temperature operation. One solvent of interest which can be used because of its ability to both degrease and be analyzed for carbon content is Vertrel™ MCA. Tests were performed to determine carbon, sulfur, and chlorine concentrations for two candidate materials which were subjected to Vertrel MCA cleaning. Comparisons with high temperature hydrogen reduction are provided. Solvent analysis, LECO carbon/low sulfur determination testing, and neutron activation testing were performed to provide comparisons. Results show potential risks of using solvent cleaning and analysis as the only method of determining impurity concentration of materials which will be exposed to high temperature testing.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

Evaluation of getters for methane and ammonia decomposition

Getters are used in many tritium purification systems for impurity removal. One getter material, SAES® ST909, can be used to decompose various impurities (methane, carbon oxides, ammonia and others), and release the hydrogen bound in these compounds for further processing. Because, ST909 absorbs eight to nine percent of its initial weight in nitrogen, alternate materials may provide greater operational flexibility to accommodate variable operating carrier gases. The gettering capability of ST909 is related to the tri-metallic alloy (zirconium, manganese, and iron) composition. However, simply using a material with the same composition may not provide similar methane and ammonia decomposition conversion efficiency. For this testing, alternative materials to ST909 are compared to track methane and ammonia decomposition performance. Bench scale tests were performed at elevated temperature using various gas mixtures. Changes in methane and ammonia decomposition performance were tracked using RGA analysis during bench scale testing. Analytical comparisons of chemically equivalent materials to ST909 were also performed and correlated to bench scale test results. Characterization testing performed to evaluate chemically equivalent materials included: X-ray fluorescence, X-ray diffraction, and inductively coupled plasma-mass spectrometry (ICP-MS). Results are expounded upon and differences in gettering capability of alternate materials are highlighted.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

Evaluation of hydrogen isotope exchange methodology on adsorbents for tritium removal

The Savannah River National Laboratory has demonstrated a potential process that can be used to remove tritium from tritiated water using Pt-catalyzed molecular sieves. The process is an elemental isotope exchange process in which H{sub 2} (when flowed through the molecular sieves) will exchange with the adsorbed water, D{sub 2}O, leaving H{sub 2}O adsorbed on the molecular sieves. Various formulations of catalyzed molecular sieve material were prepared using two different techniques, Pt-implantation and Pt-ion exchange. This technology has been demonstrated for a protium (H) and deuterium (D) system, but can also be used for the removal of tritium from contaminated water (T{sub 2}O, HTO, and DTO) using D{sub 2} (or H{sub 2}). (authors)

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

SHINE Vacuum Pump Test Verification

Normetex pumps used world-wide for tritium service are no longer available. DOE and other researchers worldwide have spent significant funds characterizing this pump. Identification of alternate pumps is required for performance and compatibility with tritium gas. Many of the pumps that could be used to meet the functional performance requirements (e.g. pressure and flow conditions) of the Normetex pump have features that include the use of polymers or oils and greases that are not directly compatible with tritium service. This study assembles a test system to determine the flow characteristics for candidate alternate pumps. These tests are critical to the movement of tritium through the SHINE Tritium Purification System (TPS).

07 ISOTOPE AND RADIATION SOURCES↗