Patent ID: 8440056

Claim:
A heat integrated distillation apparatus comprising: a rectifying column including a trayed section or a packed bed section, which is used as a rectifying section; a stripping column located higher than the rectifying column and including a trayed section or a packed bed section used as a stripping section; a first pipe for connecting a column top of the stripping column with a column bottom of the rectifying column; a single compressor installed at a midway section of the first pipe and configured to compress vapor from the column top of the stripping column and then feed the compressed vapor to the column bottom of the rectifying column; a heat exchanger located at the trayed section or packed bed section of the rectifying column; a liquid withdrawal unit located at the trayed section or packed bed section of the stripping column and configured to remove a part of liquid from the trayed section or lacked bed section to the outside of the column; a second pipe for introducing the liquid from the liquid withdrawal unit to the heat exchanger; and a third pipe for introducing fluids introduced through the second pipe to the heat exchanger and then discharged from the heat exchanger to a stage directly below the liquid withdrawal unit.