Spool and shell with pressurizing fluid activated seal

A spool and shell assembly for use in treating a material with a fluid under conditions of elevated pressure comprising:

• a pressure vessel defined by a tubular shell and a spool assembly moveable between at least a first position outside the shell and a treating position within the shell;
• said spool assembly comprising first and second cylindrical end members and a connecting rod extending therebetween;
• at least one sealing assembly carried by each of said first and second cylindrical end members for sealing said pressure vessel when said spool is in the treating position;
• each of said sealing assemblies comprising an elastically deformable sealing ring associated with the circumferential exterior of said end member and an annular compression member positioned axially adjacent said sealing ring, said compression member being arranged for reciprocating axial movement towards and away from sealing member to provide radial expansion of said sealing member for sealing and unsealing of said spool assembly.

A spool and shell assembly for use in impregnating tobacco with a tobacco expansion agent at elevated pressure comprising:

• a pressure vessel including a cylindrical tubular shell and a spool assembly;
• said spool assembly comprising first and second cylindrical end members and a connecting rod extending therebetween;
• at least one sealing assembly carried by each of said first and second cylindrical end members for sealing said pressure vessel when said spool is in the treating position;
• each of said sealing assemblies comprising at least one resiliently deformable annular sealing member associated with the circumferential exterior of at least one of said end members for sealing said spool in the treating position and an annular shaped compression member having a first axial surface of predetermined area contacting said sealing member and a second axial surface of surface area greater than said first axial surface and being arranged for fluid communication with said tobacco expansion agent.

A process for impregnating tobacco with a high pressure expansion agent comprising the steps:

• loading tobacco into an annular space of a spool body defined by first and second cylindrical end members and a connecting rod extending therebetween;
• moving said spool assembly into the interior of a tubular shell;
• applying axial pressure to an resiliently deformable sealing ring associated with the circumferential periphery of each of said end members to thereby form a sealed annular impregnation zone within said tubular shell;
• admitting expansion agent into said impregnation zone;
• and
• removing said expansion agent from said impregnation zone and releasing said axial pressure applied to said sealing members.