Tritium Systems Test Assembly Research Articles

Tritium Retention in Jet Cryopanel Samples

This paper discusses the possibility that tritium might exchange with water trapped in aluminum anodize cryopanels in JET which prompted a test program at the Tritium systems Test Assembly, TSTA. Los Alamos, New Mexico. JET furnished two test pieces of cryopanel which were exposed to tritium at approximately liquid nitrogen temperature and 25 torr pressure for nearly two weeks. One specimen was removed and the retained tritium was measured. The second specimen was subjected to several increasing temperature vacuum bakeouts and the effectiveness of the bakeouts were inferred from the pressure history of the chamber. When the retained tritium in the second specimen was measured, it was found that nearly 96% of the tritium, as measured in the first specimen, had been removed during the vacuum bakeouts. If the tritium retained in the cryopanel without bakeout were scaled to JET conditions according to a linear pressure-time relationship, the tritium expected to become trapped in the JET cryopanels would be approximately 0.6 gram.

Fabrication and Installation of the JAERI Fuel Cleanup System

This paper reports that the Japan Atomic Energy Research Institute (JAERI) has developed a full scale Fuel Cleanup System (JFCU) that processes a simulated plasma exhaust at the Tritium Systems Test Assembly (TSTA) in the Los Alamos National Laboratory (LANL). The JFCU was designed by the Tritium Process Laboratory (TPL) of the JAERI based on the component studies performed under previous TSTA-TPL collaboration and the pilot scale experiment using grams of tritium at the TPL. The JFCU accepts a simulated fusion reactor exhaust, a mixture of hydrogen isotopes with an impurity level of up to 15% at a throughput of 4.2 {times} 10{sup {minus}3} mol/s continuously and produces pure hydrogen isotopes while exhausting tritium-free waste gas. Some newly developed components, such as the Ceramic Electrolysis Cell and the large Zirconium-Cobalt bed, required special attention during fabrication and assembly.

Early experiments of JAERI fuel cleanup system at the tritium systems test assembly

The Tritium Process Laboratory (TPL) at the Japan Atomic Energy Research Institute (JAERI) has developed a Fuel Cleanup System (FCU) which accepts simulated fusion reactor exhaust and produces pure hydrogen isotopes and tritium-free waste. Under the collaboration program of USDOE and JAERI, an integrated process, the “JAERI Fuel Cleanup System” (JFCU) was designed and fabricated for testing at the Tritium Systems Test Assembly (TSTA) as a major subsystem of the simulated fusion fuel cycle. The JFCU has the capability to continuously process a mixture of hydrogen isotopes and impurities of 15 mol/h. The major components are: a palladium diffuser for hydrogen isotopes purification, a catalytic reactor for oxidation of tritium in impurities, cold traps for separation of tritiated water to produce exhaust containing a very low level of tritium, a ceramic electrolysis cell for decomposition of tritiated water, and zirconium-cobalt beds for hydrogen isotopes storage. In early 1990, the JFCU was installed in the TSTA and preliminary testing without tritium was initiated. Components such as the palladium diffuser, cold traps, catalytic reactor, scroll pump and electrolysis cell were tested independently as well as in the integrated process tests.

Development of the JAERI Fuel Cleanup System for Tests at the Tritium Systems Test Assembly

AbstractThe Tritium Process Laboratory (TPL) at the Japan Atomic Energy Research Institute (JAERI) has developed a Fuel Cleanup System (FCU) which accepts simulated fusion reactor exhaust and produces pure hydrogen isotopes and tritium-free waste. The major components are; a palladium diffuser, a catalytic reactor, cold traps, a ceramic electrolysis cell, and zirconium-cobalt beds. In 1988, an integrated FCU process loop was installed in the TPL. A number of “hot” runs were performed to study the system characteristics and improve performance. Under the US-Japan collaboration program, the “JAERI Fuel Cleanup System” (JFCU) was designed and fabricated by JAERI/TPL for testing at the Tritium Systems Test Assembly (TSTA) in Los Alamos National Laboratory as a major subsystem of the simulated fusion fuel cycle. The JFCU was installed in the TSTA in early 1990.

Continued Studies of Co-Pumping of Deuterium and Helium on a Single, 4K Activated Charcoal Panel

In 1988, a prototypical vacuum system was added to the Tritium Systems Test Assembly (TSTA) at Los Alamos National Laboratory. Since then various pumping scenarios, which might be expected in a fus...

The tritium systems test assembly at Los Alamos National Laboratory

The Tritium Systems Test Assembly (TSTA) at Los Alamos National Laboratory is a facility for the integrated testing, in full scale, of the processes and safety systems required for the reprocessing and recycling of plasma exhaust gas from a tokamak reactor. The facility can reprocess and reuse tritium at the rate of 1000 g per day, with a tritium inventory of 130 g. TSTA has been operated since 1984 with increasing amounts of tritium and an increasing degree of system integration without significant releases to the environment or doses to workers. Full loop integration was achieved in 1988. Since 1987, the TSTA has been jointly funded and jointly operated by the U.S. Department of Energy and the Japan Atomic Energy Research Institute. Objectives include: the demonstration of long-term reliability and safety, the qualification of equipment for tritium service, and the verification of a facility that can be copied for future fusion machines, such as the International Tokamak Experimental Reactor (ITER). Future plans include the installation and integrated testing of a new impurity removal system of Japanese design, testing the effect on the plasma exhaust gas reprocessing systems of off-normal conditions in the torus, and the development and testing of technology for processing tritium contained in a breeding blanket product stream.

Tritium handling experience in vacuum systems at TSTA

Compound cryopumps have been added to the Tritium Systems Test Assembly (TSTA) integrated fusion fuel loop. Operations have been performed which closely simulate an actual fusion reactor pumping scenario. In addition, performance data have been taken that support the concept of using coconut charcoal as a sorbent at 4 K for pumping helium. Later tests, reported in detail in Batzer et al, Proc 13th Symp Fusion Engng, Knoxville, TN, 2–6 Oct (1989), show that coconut charcoal may be used to co-pump D, T and He mixtures on a single 4 K panel. Rotary spiral pumps have been used successfully in several applications at TSTA and have required more than 9000 h of maintenance-free operation. Metal bellows pumps have been used to back the spiral pumps and have been relatively trouble-free in loop operations. Bellows pumps also have more than 9000 h of maintenance-free operation.

Recent Results at the Tritium Systems Test Assembly

The Tritium Systems Test Assembly (TSTA) project at Los Alamos is charged with developing and demonstrating the tritium technology required for the magnetic fusion energy program. Since June 1987 the project has been operated by Los Alamos National Laboratory under the joint funding of the US Department of Energy (DOE) and the Japan Atomic Energy Research Institute (JAERI). At TSTA the technology under development includes reactor exhaust gas processing technology and safety systems. This project is not currently investigating the processing of tritium extracted from a breeding blanket. The processing of tritium extracted from a breeding blanket is a possible upgrade to TSTA. This possible upgrade is the subject of an ongoing study among Los Alamos, JAERI and the Argonne National Laboratory (ANL). This installing such on upgraded process systems at TSTA in the 1990--1992 time frame. The exhaust gas processing system at TSTA is designed to demonstrate full-scale exhaust gas processing for a fusion machine of a size currently being designed for ITER. Of course, deuterium is also a major component of the exhaust gas. Current gas processing uses a total gas stream comprised of /approximately/65% deuterium, 35% tritium, 1-2% reactive impurities (currently nitrogen and methane) with the remainingmore » gas hydrogen and helium. The tritium inventory required to process through this loop at this rate is about 110 g. The main process loop at TSTA has been operating at this flow rate since July 1987. In addition to the operation of the main process loop, a number of nonloop experiments are underway at TSTA. This paper will update the status of both loop and nonloop studies at Los Alamos.« less

The U.S. program for fusion nuclear technology development

The Fusion Nuclear Technology (FNT) research and development program in the United States is shaped by a hierarchy of documents and by the environment for nuclear energy existing in the United States. The fission nuclear industry in the United States has suffered problems with public perception of safety, waste disposal issues, and economics as influenced by safety and environmental issues. For fusion to be a viable energy alternative, it must offer significant improvements in these areas. The hierarchy of documents defining objectives, plans, and strategy of the U.S. FNT program consists of the Magnetic Fusion Program Plan (MFPP) (February 1985), The Technical Planning Activity Final Report (January 1987), the Finesse Program Report (January 1987), and the Blanket Comparison and Selection Study Final Report (September 1984). In addition, two other documents are also significant in shaping FNT policy. These are the IEA report on Material for Fusion (December 1986) and the Summary of the Report of the Senior Committee on Environmental, Safety, and Economic Aspects of Magnetic Fusion Energy (September 1987). The U.S. Magnetic Fusion Program Plan defines four key technical issues (magnetic confinement systems, properties of burning plasmas, fusion nuclear technology, and fusion materials). The goal of the plan is to establish the scientific and technological base required for economic and environmental assessment of fusion energy in the early post-2000 time period. The Technical Planning Activity (TPA) provides the program logic for accomplishing the MFPP goal. The Development and Technology Program of the Office of Fusion Energy contains the two key technical issues: Fusion Nuclear Technology and Materials. The FNT program seeks to develop safe and environmentally acceptable systems to ensure fuel (tritium) self-sufficiency, and energy conversion systems. The fuel self-sufficiency program consists of programs to breed tritium in blankets and for processing the tritium both from the blankets and the plasma exhaust. At present only a small amount of effort is devoted to the energy conversion systems, with most of the effort on tritium production and handling. The blanket program is focused on critical feasibility issues for both solid and liquid breeders, and the Tritium System Test Assembly is focused on safe handling and processing of tritium. Throughout the blanket program, emphasis is placed on low activation materials and safety. This talk will provide details of the FNT research and development program including its structure and budget for FY 1988.

Fusion Tritium Program in the United States

The fusion technology development program for tritium in the U.S. is centered around the Tritium Systems Test Assembly (TSTA) at Los Alamos National Laboratory. Objectives of this project are to develop and demonstrate the fuel cycle for processing the reactor exhaust gas (unburned deuterium and tritium plus impurities), and the necessary personnel and environmental protection systems for the next generation of fusion devices. The TSTA is a full-scale system for a machine the size of the International Tokamak Reactor (INTOR) or the International Thermonuclear Experimental Reactor (ITER). That is, TSTA has the capacity to process tritium in a closed loop mode at the rate of 1 kg per day, requiring a tritium inventory of about 100 g. The TSTA program also interacts with all other tritium-related fusion technology programs in the U.S. and all major programs abroad. This report is a summary of the results and interactions of the TSTA program since a previous summary was published1 and an overview of related tritium programs.

The Safety Record at the Tritium Systems Test Assembly

The Tritium Systems Test Assembly (TSTA) has been operating for 4 years with tritium inventories of up to a million Ci and a cumulative (circulated) throughput of over 10 billion Ci to date. During...

The Data Collection System for Failure/Maintenance at the Tritium Systems Test Assembly

A data collection system for obtaining information which can be used to help determine the reliability and vailability of future fusion power plants has been installed at the Los Alamos National Laboratory's Tritium Systems Test Assembly (TSTA). Failure and maintenance data on components of TSTA's tritium systems have been collected since 1984. The focus of the data collection has been TSTA's Tritium Waste Tratment System (TWT), which has maintained high availability since it became operation in 1982. Data collection is still in progress and a total of 291 failure reports are in the data collection system at this time, 47 of which are from the TWT. 6 refs., 2 figs., 2 tabs.

Operating Experience and Procedures at the Tritium Systems Test Assembly

Operating procedures are important for the safe and efficient operation of the Tritium Systems Test Assembly (TSTA). TSTA has been operating for four years with tritium in a safe and efficient manner. The inventory of tritium in the process loop is 100 grams and several milestone runs have been completed. This paper describes the methods used to operate TSTA. 3 refs., 1 fig.

Code Development for Analysis of TSTA Compound Cryopumps

A Monte Carlo computer code for analyzing free molecular gas flow has been developed to study the pumping characteristics of compound cryopumps for plasma chamber evacuation of fusion reactors. The code can deal with complex internal geometries of the pumps which commonly consist of cryopumping surfaces surrounded with elements like baffles, shields, and reservoirs. This code was used to study the pumping performance of a compound cryopump in the Tritium Systems Test Assembly (TSTA) at Los Alamos National Laboratory. The results show that the calculated pumping speeds are strongly effected by the geometrical models employed in the calculations, and that an analysis based on a detailed model is essential to estimate the performance of compound cryopumps.

Tritium Proof-of-Principle Injector Experiment

The Tritium Proof-of-Principle (TPOP) pellet injector was designed and built by Oak Ridge National Laboratory (ORNL) to evaluate the production and acceleration of tritium pellets for fueling future fusion reactors. The injector uses the pipe-gun concept to form pellets directly in a short liquid-helium-cooled section of the barrel. Pellets are accelerated by using high-pressure hydrogen supplied from a fast solenoid valve. A versatile, tritium-compatible gas-handling system provides all of the functions needed to operate the gun, including feed gas pressure control and flow control, plus helium separation and preparation of mixtures. These systems are contained in a glovebox for secondary containment of tritium. Tritium experiments will be carried out at the Tritium Systems Test Assembly (TSTA) at Los Alamos National Laboratory (LANL).

Tips for the Fabrication of Temporary Tritium Experiments

The Tritium System Test Assembly (TSTA) is a facility built for the demonstration of tritium handling systems necessary for tritium-burning fusion reactors. The facility has been in operation handling tritium for four years. The current inventory of tritium is approximately one hundred grams with DOE approval exists for a maximum inventory of two hundred grams. Not all experiments performed at TSTA require the operation of the main process loop. During the last four years, many small scale experiments have been performed to test the compatibility and operation of tritium processing components in small self-contained experimental packages. These packages are fabricated inside secondary containment gloveboxes and can be operated for hours or months with little monitoring. Construction of these packages need to be tritium compatible, inexpensive, easy to build, and versatile. This paper discusses some of the problems and remedies encountered during the building of temporary experiments.

Experience of TSTA Milestone Runs with 100 Grams-Level of Tritium

The first loop operation tests of the Tritium Systems Test Assembly (TSTA) with 100 grams-level of tritium were performed at the Los Alamos National Laboratory (LANL) in June and July, 1987. The July run was resumption of the June run, which was halted because of a loss of cryogenic refrigerant in the hydrogen isotope separation system.

Advances in the Electrolysis of Tritiated Water

The exhaust plasma processing plant, proposed a few years ago as an alternative to the Tritium Systems Test Assembly plant in operation at Los Alamos National Laboratory, required further research in such areas as a low liquid inventory electrolytic cell and the types of separator or membrane resistant to beta radiation. Moreover, it was suggested that the value of the separation factors among H2, D2, and T2 should be checked during electrolysis at high D2O concentration in an alkaline medium by using different materials for the cathode.The results of experimental work carried out in these directions have shown the feasibility of the process, although some improvements can still be made in the optimization of the separators and in the design of the cell.The research carried out at the Joint Research Centre, Ispra, Italy, with support from other institutes, is described.

Tritium Technology Studies at the Tritium Systems Test Assembly

The Tritium Systems Test Assembly (TSTA) at the Los Alamos National Laboratory has been in operation with tritium since June 1984. Presently there are some 30 g of tritium in the main process loop. This 30 g has been sufficient to do a number of experiments involving the cryogenic distillation isotope separation systems. In January 1986, two major experiments were conducted. During these experiments the fuel cleanup system was interfaced, through the transfer pumping system with the isotope separation system, thus permitting testing on the integrated fuel processing loop. This integration of these systems means that of the TSTA subsystem only the vacuum system remains to be integrated into the TSTA fuel processing loop. In the period of June 1984 through May 1986, the TSTA system had processed approximately 10/sup 8/ Ci of tritium. Total tritium emissions to the environment over this period have been less than 3 Ci as elemental tritium and 2 Ci as tritium oxide. Personnel exposures during this period have totaled less than 100 person-mRem. To date, the development of tritium technology at TSTA has proceeded in progressive and orderly steps. In two years of operation with tritium, no major design flaws have been uncovered.

Data Base for Failure/Maintenance at the Tritium Systems Test Assembly

A data collection system for obtaining availability/reliability data on fusion technology has been installed at the Tritium Systems Test Assembly (TSTA) of Los Alamos National Laboratory. The system is fashioned after the Centralized Reliability Data Organization developed at Oak Ridge National Laboratory. The data collection system is currently being used at TSTA and is working well. The amount of data that has been collected at TSTA to date is not sufficient to indicate meaningful trends in availability analysis.