Liquid distillation unit with polygonal downcomer

Abstract

Abstract A liquid distillation unit is disclosed including an improved calandria formed by an outer shell and spaced tube sheets. A downtake conduit passes through the calandria and through and between the tube sheets and is surrounded by a plurality of heat exchange tubes passing between and through the tube sheets. The calandria includes an inlet and an outlet located on opposite sides so that vapor passes from the inlet across the heat exchange tubes to the outlet. The heat exchange tubes are arranged between the inlet and the outlet in multiple, parallel first rows substantially parallel with the axis passing through the inlet and outlet. Heat exchange tubes in adjacent first rows are offset with respect to each other, thus arranging the tubes in second and third multiple, parallel rows at acute angles with the first rows. The downtake conduit is located adjacent the outlet and its walls form a polygonal outline in cross-section generally symmetrical about the axis between the inlet and the outlet. Each of the walls of the downtake conduit are parallel to one of said first, second or third rows and are closely spaced to the heat exchange tube in adjacent rows. The walls of the downtake conduits are also proportioned and located with respect the outer shell to provide a flow space for the vapor around the tubes and between the downtake conduit and the outer shell which is reduced in the flow direction form the inlet toward the outlet for maintaining the vapor velocity more constant as it flows toward the outlet than would be the case if the downtake conduit were not so proportioned and located.

Inventors

• 👤 J Pottharst

Bibliographic Details