Abstract: A dry cleaning system is disclosed which utilizes liquid carbon dioxide as the cleaning medium. Two storage tanks are employed in conjunction with a cleaning vessel. One of the storage tanks is employed for pressure equalization with the cleaning vessel, while the other storage tank is employed for bulk solvent transfer to and from the cleaning vessel. The temperature drop associated with pressure equalization is limited to residual liquid solvent in the pressure equalization tank. At the completion of substrate agitation in the cleaning vessel, liquid solvent is transferred back into the bulk transfer tank, while gaseous solvent is extracted into the pressure equalization tank. The temperature of the cleaning vessel and substrates drops during vapor recovery, while the temperature in the recovered vapor is elevated. The return line from the cleaning vessel is routed back into the cleaning vessel where it forms a heat exchange coil.

Abstract: A dry cleaning process and system for cleaning articles disposed in a cleaning chamber having a rotatable member therein, using carbon dioxide (CO2) from a storage tank. The process includes causing a pressure differential between the storage tank and the cleaning chamber, filling the cleaning chamber with a predetermined amount of liquid CO2 enabling flow of liquid CO2 from the storage tank to the cleaning chamber in response to the pressure differential, and rotating the rotatable member.

Abstract: A closure system which provides a lubricated lock ring on a hinged door assembly rather than proximate a pressure vessel is provided. The configuration of this system removes lubricants from the region immediately adjacent a pressure vessel entrance to be sealed by the door assembly. A shorter entrance tunnel for access to the pressure vessel interior is also provided by this configuration. A clamp ring having radially extending lugs is rigidly affixed proximate to and partially defining the pressure vessel entrance. The door has a continuous thread about an outer circumferential surface thereof. A lock ring having a complementary interior continuous thread is in rotational communication with the threaded circumferential surface of the door. The lock ring also has plural, inwardly projecting lugs which are capable of passing between the clamp ring lugs when the door is swung toward the clamp ring.

Abstract: A dry-cleaning process for cleaning articles disposed in a cleaning chamber having jet inflow ports, using carbon dioxide (CO2) from first and second storage tanks, the process including the steps of compressing gaseous CO2 into the first storage tank to cause a positive pressure differential between the first storage tank and the cleaning chamber, filling the cleaning chamber with liquid carbon dioxide by enabling CO2 flow from the first storage tank to the cleaning chamber in response to the positive pressure differential, alternately compressing gaseous CO2 into the first or second storage tanks to cause a pressure differential between the first and second storage tanks, and flowing liquid CO2 between the first and second storage tanks, via the jet ports and through the cleaning chamber, in response to the pressure differential between the first and second storage tanks, to provide jet agitation in the cleaning chamber and a periodically continuous flow of liquid CO2 through the cleaning chamber.