Design and experimental study of adsorption bed for the helium coolant purification system

Abstract

Abstract In the design of a fusion reactor, a helium cooling system (HCS) is used to extract heat from the blanket. To reduce the permeated tritium to HCS, coolant purification system (CPS) has been developed and experimental loop has been constructed. In the present paper, the main components of the CPS loop such as oxide bed and absorption bed were introduced focusing with design, fabrication and their performance calculation. Since the molecular size of tritium is too small to be captured, it is oxidized to Q2O using a copper oxide bed. Then, the adsorption bed using molecular sieve captures Q2O through physical adsorption. For the design of CPS, correlation of previous studies and general properties of molecular sieve were used. Since the concentration of Q2 in this system is estimated as 0.4 Pa, which is very low compared to the helium pressure of 8 MPa, the used correlations for design and saturation characteristics of the absorption bed under low partial pressure of Q2O should be validated. In the present study, component test was prepared to verify the designed absorption bed, which can simulate the helium flow condition with low concentration of Q2. The test was performed under various conditions such as temperature, pressure, concentration of Q2 and velocity. The results will be used for CPS loop design.