Plate heat exchanger for separating vapor and liquid phases

Claim 1

In a heat exchange system wherein a fluid is subjected to heat sufficient to cause separation of more and less volatile components of the fluid into a substantially pure vapor phase and a liquid phase and wherein the vapor phase of the fIuid is rectified; a heat exchange device, first delivery means for delivering the fluid within the system to the heat exchange device and second and third delivery means for returning the vapor and liquid phases of the fluid to the system from the heat exchange device; the heat exchange device comprising: (a) a plurality of flat heat conductive metal plates stacked as lamination in face-to-face heat conductive relationship and bonded one to another; (b) a chamber formed by superpositioning apertures within the plates, the chamber defining a zone which receives the fluid and the zone having a configuration permitting separation of the liquid and vapor phases of the fluid under the influence of gravitational forces; (c) at least one first fluid channel means formed in at least one of the plates and defining first passage means for delivering the fluid to the chamber; (d) at least one second fluid channel means formed in at least one of the plates, the second fluid channel means communicating directly with the chamber, extending upwardly from the chamber, defining second passage means for conveying the vapor phase of the fluid upwardly from the chamber and providing for rectification of the fluid therein, and the second passage means being located adjacent the first fluid channel means and being adapted to accommodate liquid condensate which results from condensation of the vapor phase during rectification and the to permit draining of the condensate back into the chamber; (e) at least one third fluid channel means formed in at least on of the plates, being located adjacent the first fluid channel means and defining third passage means for removing the liquid phase of the fluid from the chamber; and (f) a plurality of ports extending into the stack of plates for directing the fluid to the first channel means from the first delivery means and for directing the vapor and liquid phases of the fluid into the second and third delivery means from the second and third channel means respectively, the first, second and third fluid channel means being orientated in a direction parallel to one another whereby the vapor and liquid phases of the fluid in the second and third fluid channel means flow counter to the fluid in the first fluid channel means and the fluid in the first fluid channel means receives heat by counter current thermal contact with the vapor and liquid phases of the fluid in the second and third fluid channel means, and the fluid channel means in each plate being formed within the thickness of the plate by removing a portion of the metal from the plate in a manner such that some metal is left within each channel means for the full thickness of the plate and adjacent plates are bonded in face-to-face contact at points over a major portion of the surface area of the plates.