Lubricant separation system for hvac&r system

Abstract

A heating, ventilation, air conditioning, and refrigeration (HVAC&R) system includes an evaporator disposed along a working fluid circuit, where the evaporator is configured to transfer heat between a working fluid and a conditioning fluid, and a lubricant separation system. The lubricant separation system includes a lubricant separation heat exchanger configured to receive a mixture of the working fluid and a lubricant from the evaporator and to transfer heat from a flow of heated fluid to the mixture to separate the working fluid from the lubricant. The lubricant separation system is also configured to direct the working fluid separated from the lubricant to the evaporator.

1 . A heating, ventilation, air conditioning, and refrigeration (HVAC&R) system, comprising:
 an evaporator disposed along a working fluid circuit, wherein the evaporator is configured to transfer heat between a working fluid and a conditioning fluid; and   a lubricant separation system comprising a lubricant separation heat exchanger configured to receive a mixture of the working fluid and a lubricant from the evaporator and to transfer heat from a flow of heated fluid to the mixture to separate the working fluid from the lubricant, wherein the lubricant separation system is configured to direct the working fluid separated from the lubricant to the evaporator.   
     
     
         2 . The HVAC&R system of  claim 1 , wherein the lubricant separation heat exchanger comprises a housing and a heat transfer apparatus disposed within the housing, wherein the heat transfer apparatus is configured to place the mixture and the flow of heated fluid in a heat exchange relationship. 
     
     
         3 . The HVAC&R system of  claim 2 , wherein the heat transfer apparatus comprises a block structure, the block structure comprises a base portion and a plurality of extensions extending from the base portion, the plurality of extensions defines a plurality of channels that define a serpentine flow path, and the lubricant separation heat exchanger is configured to direct the mixture to flow along the serpentine flow path. 
     
     
         4 . The HVAC&R system of  claim 3 , wherein the heat transfer apparatus comprises a plurality of tubes extending within the serpentine flow path, and the plurality of tubes is configured to direct the flow of heated fluid therethrough to place the mixture and the flow of heated fluid in the heat exchange relationship. 
     
     
         5 . The HVAC&R system of  claim 1 , wherein the lubricant separation heat exchanger comprises a shell and a plurality of tubes extending within the shell, the shell comprises an inlet configured to receive the mixture from the evaporator and an outlet configured to direct the working fluid separated from the lubricant to the evaporator. 
     
     
         6 . The HVAC&R system of  claim 5 , comprising a plurality of baffles disposed within the shell, the plurality of baffles defines a serpentine flow path through the shell, and the lubricant separation heat exchanger is configured to direct the mixture to flow along the serpentine flow path. 
     
     
         7 . The HVAC&R system of  claim 6 , wherein respective distances extending between adjacent baffles of the plurality of baffles vary along a length of the shell. 
     
     
         8 . The HVAC&R system of  claim 7 , wherein the respective distances decrease along the length of the shell from a first end of the shell proximate the inlet to a second end of the shell opposite the first end. 
     
     
         9 . The HVAC&R system of  claim 1 , wherein the evaporator comprises a hybrid falling film evaporator comprising a falling film section and a flooded section, the lubricant separation heat exchanger configured to receive the mixture from the flooded section, and the lubricant separation system is configured to direct the working fluid separated from the lubricant toward the falling film section. 
     
     
         10 . The HVAC&R system of  claim 1 , wherein the lubricant separation heat exchanger is fluidly coupled to a lubricant reservoir configured to store the lubricant, and the lubricant separation heat exchanger is configured to receive a heated flow of the lubricant as the flow of heated fluid. 
     
     
         11 . The HVAC&R system of  claim 10 , wherein the lubricant separation system is configured to direct the lubricant separated from the working fluid from the lubricant separation heat exchanger and toward the lubricant reservoir. 
     
     
         12 . The HVAC&R system of  claim 11 , wherein the lubricant separation system comprises an eductor, the lubricant separation heat exchanger is configured to direct the lubricant separated from the working fluid to the eductor, and the eductor configured to direct the lubricant separated from working fluid to the lubricant reservoir. 
     
     
         13 . The HVAC&R system of  claim 12 , wherein the eductor is configured to receive a flow of pressurized working fluid as a motive fluid, and the eductor is configured to direct the motive fluid therethrough to generate a vacuum to draw the lubricant separated from the working fluid from the lubricant separation heat exchanger and into to the eductor. 
     
     
         14 . The HVAC&R system of  claim 13 , comprising a compressor system disposed along the working fluid circuit, wherein the eductor is fluidly coupled to the compressor system and is configured to receive the flow of pressurized fluid from the compressor system. 
     
     
         15 . The HVAC&R system of  claim 14 , wherein the lubricant separation system is configured to direct the heated flow of the lubricant from the lubricant separation heat exchanger to the compressor system. 
     
     
         16 . A heating, ventilation, air conditioning, and refrigeration (HVAC&R) system, comprising:
 an evaporator disposed along a working fluid circuit; and   a lubricant separation heat exchanger configured to place a mixture of working fluid and lubricant received from the evaporator in a heat exchange relationship with a flow of heated fluid received from a heated fluid source to separate the mixture into an evaporated working fluid and a separated lubricant, wherein the lubricant separation heat exchanger comprises:   a first inlet configured to receive the mixture from the evaporator;   a second inlet configured receive the flow of heated fluid from the heated fluid source;   a first outlet configured to direct the evaporated working fluid to the evaporator; and   a second outlet configured to discharge the separated lubricant from the lubricant separation heat exchanger.   
     
     
         17 . The HVAC&R system of  claim 16 , comprising an eductor fluidly coupled to the second outlet, wherein the eductor is configured to receive the separated lubricant from the lubricant separation heat exchanger and to direct the separated lubricant to a lubricant reservoir of the HVAC&R system. 
     
     
         18 . The HVAC&R system of  claim 16 , wherein the lubricant separation heat exchanger comprises a shell, a plurality of tubes extending within the shell and configured to direct the flow of heated fluid therethrough, and a plurality of baffles disposed within the shell, wherein the plurality of baffles defines a serpentine flow path through the shell, and the lubricant separation heat exchanger is configured to direct the mixture along the serpentine flow path. 
     
     
         19 . The HVAC&R system of  claim 16 , wherein the lubricant separation heat exchanger comprises:
 a block structure disposed within a shell, wherein the block structure defines a plurality of channels, and the plurality of channels cooperatively form a serpentine flow path configured to receive the mixture and direct the mixture therethrough; and   a plurality of tubes disposed within the plurality of channels and extending along the serpentine flow path, wherein the plurality of tubes is configured to receive and direct the flow of heated fluid therethrough.   
     
     
         20 . A heating, ventilation, air conditioning, and refrigeration (HVAC&R) system, comprising:
 an evaporator disposed along a working fluid circuit;   a compressor system disposed along the working fluid circuit and comprising a centrifugal compressor configured to direct a working fluid along the working fluid circuit,   a lubricant reservoir configured to supply a lubricant to the centrifugal compressor; and   a lubricant separation system comprising a lubricant separation heat exchanger configured to transfer heat from a heated flow of lubricant received from the lubricant reservoir to a mixture of working fluid and lubricant received from the evaporator to separate the mixture into an evaporated working fluid and a separated lubricant,   wherein the lubricant separation system is configured to direct the evaporated working fluid from the lubricant separation heat exchanger to the evaporator, to direct the heated flow of lubricant from the lubricant separation heat exchanger to the compressor system, and to direct the separated lubricant to the lubricant reservoir.