1.Introduction
In 1967 SHI joined in the advanced thermal reactor project . (The thermal reactor named as “FUGEN” is cooled by light water and moderated by heavy water. ) In this project SHI experienced various kinds of tritium handling technologies. The large scale R&D for this technology was carried out through cooperation with Sulzer Chemtech Ltd. of Switzerland on the tritium removal technology for fuel reprocessing plants. In this R&D the Water Distillation technology which was developed by Sulzer was applied and modified. SHI has developed a hydrogen isotope separation technology by cryogenic distillation which might be used for the fuel recovering fusion   reactors and tritium process in extraction system in heavy water reactors. In this development we obtained various kinds of design data by using cryogenic distillation system experimental apparatus. SHI originally developed a tritium (LaNi3Mn2), which was storage   material installed in the tritium storage getter. In the field of fusion technology SHI has contributed to the development of a tritium handling technology based on the above- For example, SHI mentioned technologies. participated in the construction of the Tritium Process Laboratory (TPL) by the Japan Atomic Energy Research Institute (JAERI) and delivered some experimental apparatus. Now, SHI is undertaking a feasibility study on a tritium recovery system by water distillation for ITER. This paper summarizes the tritium handling technologies possessed by SHI.
2.Hydrogen Isotope Separation
SHI has had the following experiences with hydrogen isotope separation.
2.1 Water Distillation
This technology was basically received from Sulzer and developed by SHI to be from the fuel applied to waste water The main distinctions of reprocessing plant. this technology are shown below. · The system constitution is very simple because the treated material is just water (steam) The system operation can easily be made continuous and fully automatic because it is a distillation process system established which uses technology. · Strict management is required for the environment and working area because tritium, which is the separation object, is a radioactive material.  However, the operation pressure of this system is usually about 50-200 torr, so this system can easily prevent tritium from leaking into the environment and the safety of this system is very high. The separation method must use a tower with many separation stages bec ause the separation coefficient is small.   But the tower can be made relatively small by using the packing for hydrogen isotope separation developed by Sulzer, which is fine (small HETP). The scale of the total system can thus be made comparatively small. The Sulzer packing configuration is shown in Figure 1. We have produced large-size test apparatus for a separation system for D20/H20 and obtained preliminary data for separation ability, system operation, etc.
2.2 Cryogenic distillation
In the scope of application of fusion reactors to fuel recovering systems and heavy reactor tritium extraction systems, we are attempting to apply a cryogenic distillation technique to hydrogen isotope separation. The basic design data for the device design was acquired through the experimental apparatus which was made by SHI. The specification for this apparatus and the operational conditions of this experiment are shown below [1]. Distillation Column: ~ 17mmI.D × 500 mmH Packing: "Dicson ring" Cold Box: 600/800 mm φ  × 2100 mmH Fluid: H 2 , HD, D 2 gas Operation Pressure: 900~1300 Torr Operation Temperature: 21~25°K Hydrogen isotope analysis: Gas chromatography method (Cryogenic cooled column + TCD) carrier gas: neon
2.3 Thermal difusion (by using the column
with water cooled wall)
Because of the small scale of operation and low energy efficiency, it has been considered unsuitable for the large-scale separation of hydrogen isotopes.  However, the required inventory is small and the column construction is simple, and this method may be suitable for a tritium separation process on a relatively small scale. From above point of view, a tritium separation technique was developed at SHI by the thermal diffusion method. Also a test system has been installed in TPL and we have obtained good results  which demonstrates a successful application of the method to small- scale tritium separation[2]. The configuration of this equipment is shown in Figure 2.  This equipment was installed in a globe box with a scale of 1500L × 1200W × 3000H (mm), and operated by remote control from the control panel which was outside of the globe box.
2.4 Thermal diffusion (by using the column
with cryogenic wall)
It was pointed out that the separation coefficient was made larger when using the column with the cryogenic wall as compared to using the column with water cooled wall diagram of thermal column using [3]. SHI has actually manufactured the column with cryogenic wall and confirmed the above- mentioned increase of separation factor through experiments using this column . SHI also has the basic design data for the hydrogen isotope separation system using the thermal diffusion column with cryogenic wall. experimental apparatus An was installed in TPL and research using tritium is currently underway[4]. The schematic view of this apparatus is shown in Figure 3.
development
3.The
of
tritium
storage
material
Uranium is said to be used for tritium storage because of the following merits [5]. • larger storage capacity than other · materials · low equivalent room Figure 4 The temperature dependence of the equilibrium hydrogen pressure for the LaNi 3 Mn 2 and uranium hydrides
temperature
· high equivalent pressure at 300~400°C On the other hand, much care should be taken during the treatment and management of uranium because of its radioactivity. The development of a tritium storage material which is more suitable than uranium has been anticipated due to the treatment of a large quantity of tritium in the fuel processing of fusion reactor.  SHI studied LaNi alloy as a candidate for a tritium storage material and developed a getter which used LaNi 3 Mn, for tritium storage material[6]. Figure 4 shows the dependence of the plateau temperature pressure (van't Hof plot) for LaNi 3 Mn, and an example of  a tritium  getter using  this  material is shown in Figure 5. Although the equilibrium pressure at room temperature is slightly high for this getter material, the temperature at which it provides tritium is relatively low and the chance of tritium permeation is also low. Furthermore, as it is not radioactive like uranium, this material can be considered for use with experimental apparatus which handles small amounts of tritium.
4.The other tritium treatment technology
SHI has delivered various kinds experimental apparatus other than the above mentioned. Some of these apparatus are stated below.
· Tritium storage system
SHI assembled the apparatus using some uranium getters (manufactured by NUKEM of Germany) which was provided by JAERI, and delivered to TPL of JAERI. This system is capable of storing a large quantity (~ 30,000 Ci) of tritium at one time and provides it to other experimental apparatus as necessary. · Tritium measuring system This system is an experimental apparatus for tritium measurement of fusion fuel processing, and it was delivered to TPL of JAERI. This system is designed to the measure of high-level in tritium the fueling systems of fusion reactors. · Tritium target fabrication system This is an experimental apparatus for producing tritium targets for neutron beam sources which does not use tritium for the target material. · Tritium gas handling system for muon catalyzed fusion experiments This apparatus is a gas handling system for the purification and mixing of the target gases (duterium and tritium gas) which is the target for muon beam in this experiment. This apparatus removes impurities by a Pd filter, separates isotopes by gas chromatography, and effectively performs batch handling of a relatively small quantity of gas within a limited inventory.
5.The study  for ITER design
On the basis of above mentioned technology for hydrogen isotope separation, SHI has carried out the study of tritium recovery from the cooling water from first wall and divertor and the waste water. In this paper ,the summary of the system study at 1994 is shown as follows[8]. The tritium recovery process applied in this study is " Water distillation & VPCE (Vapor Phase Catalytic Exchange)" and the study was carried out on the following condition. • Feed condition (Cooling water) Flow rate : 100kg/h Tritium concentration : 10Ci/kg (Waste water ) Flow rate : 20kg/h Tritium concentration : 0.1 Ci/kg • Product condition (Cooling water) Flow rate : 100kg/h Tritium concentration : 0.46Ci/kg ( Waste water ) Flow rate : 20kg/h Tritium concentration : 1.0E-10 (mole fraction) The result of the study on the above design condition and the schematic flow is shown in Figure 6 and the specification of the distillation column which is the main equipment of this system is shown as follows. • Column Number : 3 • Type of Column  : Regular Packing Column : Sumitomo-Sulzer • Packing Packing CY-Type • Inside Dia. of Column Column 1-1 : 1.2m Column 1-2 ：1.2m Column 2     : 0.65m • Height of Column Column 1-1 ：29m Column 1-2 ：29m Column 2     : 48m The tritium inventory of this system was estimated as  about  2.15E+5 Ci The breakdown  is shown as follows. • Water Distillation system 1.5E+5 Ci Column 1-1&1-2 Column 2 6.4E+1 Ci Reboiler l.2E+3 Ci Other Equipments and Piping 3.6E+4 Ci • VPCE

6.The development on fusion  technology in
future
In the field of fusion technology, the development of tritium handling technology on the basis of will be continued the technology held by SHI.  Particularly, SHI will make an  effort to  develop  the following. · On the ITER design, SHI continues to study tritium recovery from cooling water and waste water on the basis of the above- mentioned isotope separation technology. • SHI aims to develop new technology for tritium  measurement-management.
7.Summary
SHI possesses various kinds of tritium handling technology. The main technologies of these developments are Hydrogen Isotope Separation and the development of tritium storage material.  Hydrogen Isotope Separation distillation, are technologies the     water cryogenic distillation and thermal diffusion methods. On the other hand, SHI developed LaNi alloy as a tritium storage material. On the basis of these technologies, SHI is undertaking research and development of a tritium recovery system for ITER design. In the field of fusion technology, the development of tritium handling technology will be continue in future.  Particularly, SHI will make an effort to study ITER design and new technology develop for  tritium measurement.