Patent ID: 7526925
Filing Date: 2009-05-05
Classification: B01B,B01D,C01B,C01P

Abstract:
1. A method of producing slush nitrogen comprising the steps of: providing a vessel with a nozzle inside the vessel; providing a liquid nitrogen supply external from the vessel; depressurizing the vessel substantially to a triple point pressure of nitrogen; introducing liquid nitrogen from the liquid nitrogen supply into the vessel, which is kept substantially free of liquid nitrogen, and spraying the liquid nitrogen into the vessel through the nozzle with a nozzle diameter and a spraying pressure adjusted for the liquid nitrogen to produce droplets that disperse, in the vessel; vaporizing the droplets by latent heat vaporization to solidify the droplets into fine solid nitrogen particles having a uniform particle diameter in the vessel, which is kept substantially free of liquid nitrogen other than the liquid nitrogen sprayed through the nozzle; and separately introducing the liquid nitrogen from the liquid nitrogen supply into the vessel after the solid liquid nitrogen particles have been formed and mixing the solid nitrogen particles with the liquid nitrogen.