Combination filter apparatus for use with a dry cleaning machine

Combination filter apparatus for use with a dry cleaning machine using dry cleaning solvent comprising:

• steam supply means,
• condensing means having a cooling coil for condensing water and solvent vapor to convert it from vapor phase to liquid phase, said condensing means having a vapor inlet and a liquid outlet;
• solvent-water separator means for separating water from solvent, said separator means having an inlet connected with the outlet of said condensing means, a discharge for water and a separate discharge for solvent,
• absorption means comprising an absorption housing and a bed of activated carbon pellets in said housing, said housing having an air and vapor inlet, an air outlet, a steam inlet and a vapor outlet, means for passing air containing solvent vapor through said absorber means from said air inlet to said air outlet for removal of solvent vapor from the air by said activated carbon pellets, valve-controlled conduit means for supplying steam to said steam inlet to heat said activated carbon pellets to vaporize absorbed solvent, and valve-controlled conduit means for conducting steam and solvent vapor from said absorption means to said condensing means for condensation therein,
• a plurality of like filter cartridge housings each of which is of a size and shape removably to receive a filter cartridge and has a dirty solvent inlet, a clean solvent outlet, and a steam inlet and a vapor outlet;
• first valve controlled conduit means for selectively conducting dirty solvent from a dry cleaning machine to the dirty solvent inlet of one or more of said filter cartridge housings for passage through a filter cartridge in said housing and for conducting clean solvent from said clean solvent outlet to the dry cleaning machine;
• valve controlled drain means at the bottom of each of said filter cartridge housings for draining solvent therein,
• second valve controlled conduit means for conducting live steam from said steam supply means selectively to said steam inlet of one or more of said filter cartridge housings to vaporize solvent in a filter cartridge therein and for conducting steam and solvent vapor to said vapor inlet of said condensing means and discharge of the resulting solvent and water to said solvent-water separator means for separation of said solvent from said water,
• said first valve controlled conduit means and second valve controlled conduit means including separate valves for each of said cartridge housings, whereby dirty solvent from said dry cleaning machine can be passed through a filter cartridge in one of said filter cartridge housings simultaneously with steam being conducted to another of said filter cartridge housings to vaporize solvent in a filter cartridge therein, and
• third valve controlled conduit means for selectively connecting said filter cartridge housings to said air and vapor inlet of said absorption means to draw air containing solvent vapor from said cartridge housings to said absorption means, said cartridge housing having valve-controlled vent openings for admission of air to said filter cartridge housings.