Abstract: The apparatus and method includes the heating of an inert gas stream, such as nitrogen or inert gas with a low oxygen content, to remove volatile organic compounds from an adsorption bed. The inert gas is then cooled by an evaporator to precipitate or condense the volatile organic compounds into a sump. Gas sensors sense the various volatile organic compound gas concentrations at the inlet and discharge of the evaporator and send signals representative of the concentrations to a signal processor and control logic module. The signal processor and control logic module selectively opens and closes valves which lead from the sump to various containers thereby separating various volatile organic compounds into selected containers. Further, the signal processor and control logic module can generate process control signals to vary the operation of the heating of the gas stream, the cooling of the gas stream, and the circulation of the gas stream.

Abstract: Fluid-carrying tubes for a heat exchanger are provided with internal longitudinal fins formed separately from the tube itself. One form utilizes individual elongated V-shaped strips biased radially outwardly by an annular sheet metal spring, with the tips of the fins brazed to the inner surface of the tube wall. Second and third embodiments utilize a one-piece corrugated sheet metal cylinder rather than individual strips, but with adjacent fins being almost completely severed from each other to provide sharp edge contact between the tips of the fins and the tube wall for optimum brazing. Either the fins or tube inner wall is clad with a lower-melting point material which permits furnace brazing of the fin tips to the tube wall. All three forms have longitudinally spaced holes and slots to enhance heat exchange by inducing transverse fluid flow through the fins and to allow liquid levels to equalize.

Abstract: Annular fins for a heat exchanger are fabricated in circumferential segments, arranged end to end, with each segment having inner and outer edges of identical but radially spaced contour, so that such segments can be stamped from a blank without any scrap created between the common edges of adjacent segments.