Condenser cold trap unit with separate fraction collection feature

Abstract

A condenser cold trap unit for recovering as separate primary and secondary condensate fractions solvents contained in an effluent drawn from products being dried in a vacuum chamber includes inner and outer shell vessels, the inner shell vessel be disposed coaxially with the outer shell vessel inside said outer shell vessel with a space being present in the outer shell vessel under the bottom of the inner shell vessel and in a course surrounding the exterior of the inner shell vessel. A cover closes off the open tops of the two shell vessels and the interior space of the outer shell vessel is sealed from communication with outside atmosphere, and the interior space of the inner shell vessel is sealed from any communication with the interior space of the outer shell vessel. A common refrigeration coil encircles the exterior of the inner shell vessel and extends down therefrom to effect solvents condensing temperature levels cooling in both shell vessels. Fittings on the cover allows for connection of the outer vessel condensing chamber with outlet from the drying chamber and for passing effluent subjected to primary solvent fraction condensing in the outer vessel chamber to the inlet of the vacuum pump that evacuates the chamber. Cover fittings allow return of exhaust from the vacuum pump to be directed into the inner vessel for condensing solvent secondary fraction and for venting solvent free gas to the outside atmosphere. Drain fittings at the bottom of each vessel allow draining collected recovered solvent to disposal.