Controlled nucleation during freezing step of freeze drying cycle using pressure differential ice crystals distribution from condensed frost
US9435586B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 12, 2014 |
| Grant date | Sep 6, 2016 |
| Priority date | — |
| Expiry date | Feb 7, 2035 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF26B5/06
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A method of controlling and enhancing the nucleation of product in a freeze dryer, wherein the product is maintained at a predetermined temperature and pressure in a chamber of the freeze dryer, and a predetermined volume of condensed frost is created on an inner surface of a condenser chamber separate from the product chamber and connected thereto by a vapor port. The opening of the vapor port into the product chamber when the condenser chamber has a pressure that is greater than that of the product chamber creates gas turbulence that breaks down the condensed frost into ice crystals that rapidly enter the product chamber for even distribution therein to create uniform and rapid nucleation of the product in different areas of the product chamber.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.