| 摘要 |
A process and apparatus for impregnating a cellular material with liquefied gas at a predetermined pressure for subsequent expansion of the impregnated cellular material including the steps of charging the cellular material into an impregnation vessel 22, purging the impregnation vessel 22 with inert gas, pressurizing the impregnation vessel 22 with inert gas to the predetermined pressure, transferring liquefied inert gas into the impregnation vessel 22 from a process vessel 12 in which the liquefied gas is stored at the predetermined pressure, soaking the cellular material in the liquefied inert gas for a predetermined time period, transferring unabsorbed liquefied gas from the impregnation vessel 22 to the storage vessel 12, depressurizing the impregnation vessel 22 by venting the inert gas therefrom and removing the impregnated cellular material from the impregnation vessel 22, the inert gas used to purge and pressurize the impregnation vessel 22 being taken from a source 56, 62 completely independent of the liquefied inert gas contained in the process vessel 12. Pressure and temperature variation in the process vessel 12 is minimized by using an external source of inert gas for the purging and pressurization steps. <IMAGE> |
