Heat exchanger and process for devolatilizing polymer using same

A plate heat exchanger comprising:

• at least one heating plate and a plurality of heating tubes, wherein the heating tubes are positioned such that they can heat the heating plates using a heat transfer fluid flowing through the heating tubes, and wherein the heating tube comprises a return tube nested inside of a supply tube;
• wherein the supply tube receives and then carries the heat transfer fluid, and wherein heat is conducted from the heat transfer fluid into the heating plate;
• wherein upon reaching a bottom of the heating tube the heat transfer fluid has lost at least a part of the heat it carried to the heating plate and said fluid is relatively cooler;
• and
• wherein the relatively cooler heat transfer fluid then enters the return tube and passes out of the heating tube.

A plate heat exchanger comprising at least one heating plate and a plurality of heating tubes wherein the heating tubes are positioned such that they can heat an object using a heat transfer fluid flowing through the heating tubes and wherein the heating tube comprises a supply tube nested inside of a return tube;

• wherein a heat transfer fluid passes first into the supply tube and travels down through the annulus between the interior of the supply tube and exterior of the return tube, and wherein the heated transfer fluid conductively heats any object in contact with the tube;
• wherein upon reaching a bottom of the heating tube, the heat transfer fluid has lost at least a part of the heat it carried to the heating object late and said fluid is relatively cooler;
• and
• wherein the relatively cooler heat transfer fluid then enters the return tube and passes out of the heating tube.