A helium isotope separation device with flow visualization unit

Abstract Distillation, adsorption, and thermal diffusion are commonly employed methods for separating He-3 and He-4 isotopes. However, due to the exceptionally low concentration of He-3 present in natural gas or natural helium, an initial enrichment of He-3 is necessary to reach the minimum concentration required for traditional separation methods. Superleak offers a straightforward and effective method for the preliminary separation of He-3 and He-4. This paper introduces a new separation device that employs a GM cryocooler as the cold source and incorporates optical windows for precise real-time flow detection. The main focus of this paper is on the rational design of the cryostat structure and the improvement of the heating method to ensure precise heating of the fluid at the superleak outlet. Additionally, a thorough analysis of heat leakage was conducted to ensure that the integration of optical windows would not affect the cryogenic separation process.