Annular heat exchanger

A devolatizing heat exchanger, the heat exchanger comprising a generally annular body having a first axially closed end and a second open end, the annular body having a generally annular wall and generally axially extending heat exchange fluid conduits generally uniformly axially disposed, within the body a plurality of generally radial conduits disposed in the annular wall, providing communication between an inside space defined by the annular wall and space external to the annular wall, the radial passageways having a length to diameter ratio of at least 4, the heat exchanger being disposed within a jacketed vessel having heat exchange fluid connections providing ingress and egress for a heat exchange fluid to a jacket of the jacketed vessel, the jacketed vessel having an upper end and a lower end, a volatile outlet port disposed between the upper and lower ends, the volatile outlet port providing communication between space internal to the jacketed vessel and space external thereto, a material discharge port at the lower end of the jacketed vessel, a header assembly directly affixed to the upper end of the jacketed vessel, the header assembly being of generally cylindrical configuration, the header assembly being partially disposed within and coaxial with the annular heat exchanger and partially external to the jacketed vessel, the header defining a generally cylindrical cavity within the header adjacent the heat exchanger, said cavity being generally coaxial with the heat exchanger, an annular space between the heat exchanger annular wall and header assembly defined by the heat exchanger and header assembly, a material supply passage defined by the header assembly disposed external to the jacketed vessel, the material supply passage being in communication with the header generally cylincrical cavity, the generally cylindrical cavity being in coummunication with the annular space between the heat exchanger and the header assembly at a location remote from the material supply passage and generally adjacent the first axially closed end of the generally closed body, a plurality of pins disposed within the cylindrical cavity of the header assembly, the pins extending generally radially inward, and a rotatable agitator rotatably disposed within the cylindrical cavity, the agitator having a plurality of blades adapted to interdigitate with the pins.