Flashing liquid refrigerant and accumulating unvaporized portions at different levels of a single vessel

Claim 2

A refrigeration method comprising the steps of: a. flashing a liquid refrigerant into the upper portion of an enclosed chamber thereby vaporizing a portion of said refrigerant; b. accumulating unvaporized liquid refrigerant at an intermediate level in said chamber thereby establishing a first body of liquid refrigerant in said chamber; c. flowing accumulated unvaporized liquid from a level above said intermediate level to a lower level in said chamber, thereby limiting the maximum level of said first body of liquid refrigerant and establishing a second body of liquid refrigerant at said lower level; d. utilizing liquid from said first body and said second body of liquid refrigerant in separate refrigeration stages at different pressures; wherein a first vapor stream is removed from said chamber through a conduit in the upper portion thereof above said first body of liquid refrigerant and a second vapor stream is removed from said chamber through a conduit in the lower portion thereof below said first body of liquid refrigerant and above said second body of liquid refrigerant.

Claim 3

The refrigeration method of claim 1 wherein step (d) comprises: flowing liquid from said second body of liquid refrigerant into a high pressure exchange stage without further flashing; and flashing liquid from said first body of liquid refrigerant for use in a low pressure heat exchange stage.

Claim 4

The refrigeration method of claim 2 wherein said first vapor stream and said second vapor stream are combined, the combined vapor is returned to a refrigerant compressor, and said combined vapor is compressed, condensed and returned to step (a) as said liquid refrigerant.

Claim 5

The refrigeration method of claim 2 also including the step of passing a process stream being refrigerated in heat exchange first with said liquid from said second body of liquid refrigerant in said higher pressure heat exchange step and then with said flashed liquid from said first body of liquid refrigerant in said lower pressure heat exchange step.

Claim 6

Refrigeration apparatus comprising: a. a closed vessel; b. a generally horizontally disposed liquid holding tray in said chamber spaced from the bottom thereof; c. a weir connected with said tray, said vessel, said tray and said weir being associated one with another to form a first liquid holding space from which liquid is permitted to flow from said tray into a lower portion of said vessel comprising a second liquid holding space only when the height of liquid on said tray is greater than the liquid overflow height of said weir; d. a first fluid conduit communicating with said first liquid holding space and with the exterior of said vessel to remove liquid from said first liquid holding space; e. a second fluid conduit communicating with said second liquid holding space and with the exterior of said vessel to remove liquid from said second liquid holding space; f. a third fluid conduit communicating with said vessel above said tray to supply feed to said vessel; g. a fourth fluid conduit communicating with the upper portion of said vessel above said first liquid holding space and above said third fluid conduit to remove vapor from the upper portion of said vessel; and h. a fifth fluid conduit communicating with the lower portion of said vessel above said second liquid holding space and below said tray to remove vapor from the lower portion of said vessel.

Claim 7

Refrigeration apparatus comprising: a. a closed vessel; b. a generally horizontally disposed liquid holding tray in said chamber spaced from the bottom thereof; c. a weir connected with said tray, said vessel, said tray and said weir being associated one with another to form a first liquid holding space from which liquid is permitted to flow from said tray into a lower portion of said vessel comprising a second liquid holding space only when the height of liquid on said tray is greater than the liquid overflow height of said weir; d. a first fluid conduit communicating with said first liquid holding space and with the exterior of said vessel to remove liquid from said first liquid holding space; e. a second fluid conduit communicating with said second liquid holding space and with the exterior of said vessel to remove liquid from said second liquid holding space; f. a third fluid conduit communicating with said vessel above said tray to supply feed to said vessel; g. a fourth fluid conduit communicating with the upper portion of said vessel above said first liquid holding space and above said third fluid conduit to remove vapor from the upper portion of said vessel; and h. a fifth fluid conduit communicating with the lower portion of said vessel above said second liquid holding space and below said tray to remove vapor from the lower portion of said vessel.

Claim 8

The refrigeration apparatus of claim 5 also including a generally vertical baffle extending downwardly from said tray to a location intermediate the top and bottom of said second liquid holding space.

Claim 9

The refrigeration method of claim 2 wherein fluid flows from said second body of liquid refrigerant to said high pressure heat exchange stage, is partially vaporized and returned to said chamber at a level below said first body and above said second body of liquid refrigerant.

Claim 10

The refrigeration method of claim 7 wherein the liquid from said first body of liquid is flashed in a second chamber from which liquid flows to said low pressure heat exchange stage, is partially vaporized and returned to said second chamber, and vapor is removed from said second chamber and returned to a refrigerant compressor at a first pressure and vapor from said first chamber is returned to said refrigerant compressor at a second pressure higher than said first pressure.

Claim 11

The refrigeration apparatus of claim 6 also including: a second closed vessel communicating with said first fluid conduit; a first heat exchanger having first and second heat exchange passageways, the inlet of said first passageway communicating with said second fluid conduit; a second heat exchanger having third and fourth heat exchange passageways; a sixth fluid conduit communicating with the inlet of said third passageway and with the lower portion of said second closed vessel; a seventh fluid conduit communicating with the outlet of said third Passageway and with said second closed vessel at a point above said sixth fluid conduit; an eighth fluid conduit communicating with the outlet of said first passageway and with said closed vessel in the lower portion thereof.

Claim 12

The refrigeration method of claim 1 wherein said liquid refrigerant is substantially a single component refrigerant whereby the composition of refrigerant accumulated at said intermediate level is substantially the same as that accumulated at said lower level.