Robert H. Sherman

The molar polarizability of3He at low temperatures and its density dependence

Simultaneous capacitance and PVT measurements on liquid and gaseous3He under a variety of temperature and pressure conditions indicate that the molar polarizability of the classical Clausius-Mossotti equation can best be expressed as:α(mole/cm3)=0.123413−0.002376 ρ(g/cm3). Some significant, but often neglected, experimental corrections are discussed.

Experimental Results from Hydrogen/Deuterium Distillations at the Tritium Systems Test Assembly

Fundamental operating parameters and column performance have been measured on the interlinked, four-column cryogenic distillation system at the Tritium Systems Test Assembly. Using mixtures of hydrogen and deuterium, data have been gathered and are given here on liquid holdup in the column packing and liquid level in reboilers (factors important to isotope inventory), pressure drop in the column packing, and product purity. Both Raman spectroscopy and gas chromatography were used for product analysis.

Single column and two-column H-D-T distillation experiments at TSTA

Cryogenic distillation experiments were performed at TSTA with H-D-T system by using a single column and a two-column cascade. In the single column experiment, fundamental engineering data such as the liquid holdup and the HETP were measured under a variety of operational conditions. The liquid holdup in the packed section was about 10--15% of its superficial volume. The HETP values were from 4 to 6 cm, and increased slightly with the vapor velocity. The reflux ratio had no effect on the HETP under the condition that the vapor velocity was almost constant. For the two-column experiment, dynamic behavior of the cascade was observed.

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.

On-line Tritium Process Gas Analysis by Laser Raman Spectroscopy at TSTA

Laser Raman spectroscopy has been applied to the on-line analysis of the operation of the cryogenic Isotope Separation System (ISS) at the Tritium Systems Test Assembly (TSTA). A flow-through cell was employed to permit near real-time observation of the dynamic response of the 3-column ISS. Accurate analysis of hydrogen isotopic mixtures may be made in less than 2 minutes. Full response to a change in the sampling point is achieved in approximately one minute. In this paper, response measurements are shown as well as static column profiles and dynamic response to induced parameter changes. Cross check of analysis was performed with radio-gas chromatography.

Experimental Study for Separation Characteristics of Cryogenic Distillation Columns with An H-D-T System

This paper reports on cryogenic distillation experiments that have been performed with an H- D-T system (1.5 g of tritium) by using two columns with different inner diameters (1 and 2 cm) and different size packings (a 3-mm Dixon ring for the larger column and a 1.5- mm Dixon ring for the smaller column). The height equivalent to a theoretical plate (HETP) values measured during total reflux operation ranged from 4 to 6 cm for both columns and showed no apparent dependence on vapor velocities. The HETP values under total recycle operation, which varied from 3 to 6 cm, gradually decreased with increasing reflux ratios. The feed flow rates also had influenced the HETP. Consequently, the HETP values were correlated by the flow rates of the feed and vapor streams of the column and by the reflux ratio.

Cryogenic Hydrogen Isotope Distillation for the Fusion Fuel Cycle

Cryogenic distillation is an attractive method for the hydrogen isotopic separations required in fusion fuel cycles. The theoretical and practical aspects of designing and constructing such systems...

Beta-decay induced reaction studies of tritium by laser Raman spectroscopy : T2CO system

The dynamic measurement of the reaction in T{sub 2}-CO 1:1 mixed gas was carried out using laser Raman spectroscopy. A catastrophic change was observed in the Raman spectra due to appearance of fine particles floating in the quartz Raman cell at about 100 min after mixing. Assignment of the new peaks on the spectra due to appearance of the particles was not successful. An attempt to specify the solid reaction product by mass spectroscopic analysis of the gas phase constituent showed the elemental formula of the product was about C{sub 1.4}:T{sub 3.0}:O{sub 1.0}. 18 refs., 3 figs., 2 tabs.

Some tips on tritium technology

This collection of practical suggestions should prove useful to workers at tritium installations where gloveboxes and cleanup systems are used, or where upgrades to such systems are anticipated. These tips are effective approaches to meeting todays stringent containment requirements, and include many applications and extensions of accepted tritium practice, plus a few innovations of our own. The subjects covered are tritium piping systion, tritium monitoring, and contamination control. Some specific problems arising out of recent experience are also discussed, along with some tentative solutions.

Demonstration of ``regulatory`` process controls on the TSTA cryogenic distillation system

Due to the nature of its fusion reaction, most of the DT used to fuel the International Thermonuclear Experimental Reactor (ITER) will exit unreacted. This effluent will be purified by the fuel cleanup system so that the isotope separation system (ISS) will be fed only hydrogen isotopes and possibly some helium. The ISS will separate this feed into streams nominally composed of He/H2/HD, D2, DT, and T2. These products will be recycled through appropriate fueling systems back to the fusion reactor or returned to storage. The ISS will have to respond properly to feed conditions which change rapidly. Feed changes will propagate quickly through the entire cascade. It is apparent that an automatic control system will be required to respond to these changes and maintain product quality. It is convenient to divide such a distillation control system into `regulatory` controls and composition controls. The `regulatory` controls include liquid levels, flowrates, reboiler heats, and pressure. A system of regulatory controls has been devised and installed on the four-column cascade of cryogenic columns at the Tritium Systems Test Assembly (TSTA) at Los Alamos National Laboratory. This tritium-compatible ISS is designed for approximately 1/10 the ITER flowrate and is dedicated to fusion fuel studies. Details of the TSTA ISS have been published previously.