Vertical oil separator
A vertical oil separator for separating oil from a refrigerant gas and oil mixture on the high side of a refrigeration/chiller system comprising, a vertical housing having an upper chamber with a cylindrical sidewall and tangentially oriented inlet for the refrigerant gas and oil mixture, said upper chamber having a refrigerant gas outlet therefrom, said housing also having a lower chamber below the upper chamber with an oil outlet therefrom, a baffle constructed and arranged in said housing to define said upper and lower chamber, at least one oil filter in said upper chamber for removing oil out of the mixture and transferring such oil downwardly from the upper chamber.
The present invention relates generally to the commercial and industrial refrigeration art. More particularly, the invention is directed to improvements in vertical oil separators for efficiently separating oil and refrigerant gas on the high side of a refrigeration system.
BACKGROUND OF THE INVENTIONThe maintenance of lubricating oil in a refrigeration system compressor is critical to its efficient operation and life span. Clearly the compressor is the principal driving force in any refrigeration or chiller system—it compresses refrigerant gas and discharges it on its high pressure side to a condenser in which the gas is condensed to a liquid phase, and thence it passes to an evaporator or like cooling coil through an expansion device reducing the refrigerant's pressure and permitting absorption of heat and expanding the liquid phase gas back to a gaseous phase on the low suction side of the compressor. All types of compressors—reciprocating, screw, scroll, centrifugal—employed in refrigeration systems use oil as a lubricant and sealant, and during operation some amount of this oil is entrained in the hot compressed refrigerant vapor discharged on the high side out to the system.
It is clear that the lubricating oil serves no useful purpose outside the compressor. Oil does not have as good heat transfer capability as the refrigerant and will reduce the efficiency of the condenser and evaporator functions. Although some amount of oil is generally present throughout the system, it is important to return most of it back to the compressor for its safe and efficient operation and to prevent oil from building up in other system components. The importance of good compressor lubrication cannot be overemphasized; and it may be noted that a typical screw compressor, for instance, may require several gallons of oil per minute.
In the past, high side oil traps or separators have been employed to separate out oil from the refrigerant gas in route from the compressor to the condenser. Such oil separators, as discussed in U.S. Pat. Nos. 4,478,050; 4,506,523; 5,133,671; and 5,271,245, are known for separating oil from the high side refrigerant gas and oil mixture, but these and other prior oil separators are deficient in performance, cost, size, system complexity and other limiting factors.
Thus it is important to provide an oil separator that provides distinctive improvements in efficient oil separation performance, simplicity of design for manufacturing cost reduction and for installation and maintenance ease.
SUMMARY OF THE INVENTIONThe invention is embodied in a vertical oil separator for separating oil from a refrigerant gas and oil mixture on the high side of a refrigeration/chiller system comprising a vertical housing having an upper oil separation chamber with a cylindrical side wall and a tangentially oriented inlet for the refrigerant gas and oil mixture, said upper chamber having a refrigerant gas outlet therefrom, the housing also having a lower oil collection chamber below the upper chamber with an oil outlet therefrom, a baffle constructed and arranged in the housing between the upper and lower chambers, and a filter device in the upper chamber for entrapping oil out of the mixture and transferring such oil downwardly from the upper chamber past the baffle into the lower chamber.
The principal object of the invention is to provide an oil separation system having a highly efficient oil-refrigerant separator section and a liquid oil reservoir section. Thus, in one aspect of the invention an oil and gas mixture inlet is tangentially arranged in an upper separation section to impart a swirling action impinging the mixture by centrifugal force against and through a screen liner to remove the oil, a refrigerant gas outlet is centrally positioned in the upper section and a transverse baffle forms a division of the upper section from a lower oil accumulation reservoir, the baffle effectively restricts centrifugal vortex action to the upper section while keeping the lower oil collection reservoir relatively static and is arranged to provide a nonrestricting passageway for oil flow from the upper section to the lower section, and an oil outlet is provided for removing oil from the lower section.
Another object is to provide an efficient, easily serviced and economic oil system for a compressor driven refrigeration/chiller system. Thus, in another aspect of the invention the incoming high pressure oil-refrigerant gas mixture is given a high degree of centrifugal action to separate out the oil on a collection device in an upper inlet section, and such turbulent action is substantially eliminated from a lower liquid oil accumulator section by a dividing baffle
In another aspect, the oil separator invention provides an upper oil-gas mixture separation section with a tangential inlet to impart centrifugal action, an oil collection and transfer device has primary and secondary components to separate oil from the refrigerant gas and transfer it in liquid form, a centrally-disposed gas outlet removes refrigerant; a lower oil accumulator section receives liquid oil from the primary and secondary collection members; and a baffle between the upper and lower sections and restricts turbulent centrifugal action to the upper section while accommodating unrestricted oil flow to the lower section.
In another aspect of the invention the oil separation invention is embodied in an oil receiving mesh of substantial-thickness impacted against by incoming oil-laden refrigerant and being arranged to accumulate and hold oil in liquid form without re-entrainment back into the refrigerant discharge vapor.
These and other objects and advantages will become more apparent hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGSFor illustration purposes, together with the accompanying written disclosure, the invention is embodied in the parts and the combinations and arrangements of parts hereinafter described. In the drawings, wherein like numerals refer to like parts wherever they occur:
For the purposes of disclosure, a closed refrigeration or chiller system 10 includes a compressor 12 connected on its high pressure outlet side to a condenser 14 through an oil separator 16 embodying the invention to be described. Typically the compressor 10 requires a large amount of lubricating and cooling oil in operation, and such oil is entrained in the hot compressed refrigerant to form an oil-gas mixture that is discharged on the compressor high side through conduit 17 to the oil separator inlet 18. It has been reported that the oil content in the oil and refrigerant gas mixture from a chiller system compressor is over 50,000 ppm (parts per million). The compressor 12 is also in fluid communication with the oil separator 16 through an oil return conduit 19 from oil outlet 20 through which oil is returned to and maintained in the compressor at a preselected level by a conventional oil level regulator (not shown) or the like. The condenser 14 is connected in fluid communication with the oil separator 16 through a refrigerant gas conduit 21 from the gas outlet 22. The hot compressed refrigerant gas (and a minor, acceptable amount of entrained oil) passes through conduit 21 to condenser 14 in which it is cooled and condensed into a high pressure liquid phase. The condenser 14 connects through conduit 23 to an evaporator 24 or like heat exchanger through an expansion valve 26. Refrigerant liquid is caused to expand and absorb heat to provide refrigeration: in a chiller system this heat exchange takes place between the expanding liquid refrigerant and a chilled liquid whereas in a typical commercial refrigeration system the expanding refrigerant absorbs heat from a circulating airflow that cools a space or product zone. In either case the refrigerant liquid absorbs latent heat and changes to a gaseous phase, and is returned to the compressor 12 on its low side through suction conduit 27 to complete the refrigeration cycle.
Referring now to
A refrigerant vapor outlet conduit 41 is centrally disposed within the upper section 34 and connects to the outlet 22 in the refrigerant circuit to the condenser 14. As shown best in
The main housing 30 of the oil separator 16 also defines a lower oil collection section 44 forming a reservoir chamber 45 for accumulating and storing a supply of liquid oil to be returned, as needed, through oil outlet 20 to the compressor 12. Turbulence of the oil in the reservoir 45 is not desirable, and it is therefore important to render this lower chamber substantially static. To this end, a divider wall or baffle member 47 is vertically disposed in the vessel and the lower zone 35c of the upper chamber or section 34 forms a separation zone between the upper and lower sections 34 and 44. This baffle member 47, in one form, is an upwardly-domed, circular, dish-shaped wall 48 with a downwardly extending peripheral flange 49 and being constructed and arranged to form an effective barrier that restricts the turbulent circular vapor flow action to the upper section 34, and primarily the upper and intermediate zones 35a, 35b thereof, while accommodating the free downward passage of liquid oil from the upper section 34 to the lower oil collecting section 44. As shown in
From the foregoing it will be seen that the oil separator unit of the present invention is simple in design; but highly efficient. One feature of novelty resides in the oil filtration device having a screen collection member 39 constructed and arranged to enhance the passage of oil particles therethrough while having a sufficient body depth and surface structure to hold or entrap the oil particles as they are pushed through by the pressurized gas vortex, and at least one other oil filter device (e.g. final screen filter 43) for providing optimum oil removal from the refrigerant gas upstream of its outlet 42 from the upper chamber. Thus, the oil particles amass and form a liquid oil curtain flowing down the inner chamber wall surface 38 to and around the baffle 47. Another feature is the offset, asymmetrical arrangement of the baffle that accommodates free oil passages therepast into the lower oil collection reservoir 45 and keeps it static by blocking and restricting gas turbulence to the upper section 34.
Referring to
Referring to
Referring now to
The oil separator (16, 116, 216, 316) of the present invention may be further modified to accommodate size or space limitations of the other system components or the operational volume demands for oil. For instance in another embodiment illustrated in
From the foregoing it will be evident that the oil separator of the present invention provides a greatly improved and simplified oil separation and reservoir apparatus that meets the objects set forth. The scope of the invention encompasses such changes and modifications as will be readily apparent to those skilled in the art and within the scope of the appended claims.
Claims
1. A vertical oil separator for removing oil from a refrigerant gas and oil mixture on the high side of a refrigeration/chiller system comprising:
- a housing having upper and lower sections separated by a baffle, said upper section forming an oil separation chamber above the baffle and having a sidewall with an inlet constructed and arranged to receive the refrigerant gas and oil mixture from the system and produce a circulating flow path around the sidewall of the upper chamber, and a refrigerant gas outlet spaced from the sidewall within the upper chamber,
- said lower section forming an oil receiving chamber below the baffle and having an oil outlet therefrom,
- a first oil filter device associated with the sidewall in said upper chamber for removing oil from the circulating flow of the gas and oil mixture, and at least one other filter device for removing oil from the circulating flow path upstream of the refrigerant gas outlet from the upper chamber.
2. The oil separator of claim 1, wherein said upper section has upper, intermediate and lower zones, said inlet for the refrigerant gas and oil mixture from the system being disposed in the upper zone and said refrigerant gas outlet being disposed therebelow in the intermediate zone, and said first oil filter device comprising a primary mesh liner extending around the sidewall in the upper zone of the upper section to thereby perform the primary oil separation function of said oil separator.
3. The oil separator of claim 2, wherein said other filter device comprises a secondary mesh liner constructed and arranged in the circulating flow path downstream of the primary mesh liner to supplement the removal of oil before discharging refrigerant gas from the intermediate zone through the gas outlet.
4. The oil separator of claim 3, wherein the refrigerant gas outlet comprises an outlet conduit extending into the intermediate zone of the upper section and having an outlet opening through which refrigerant gas passes into the outlet conduit and downstream to the system, and said secondary mesh liner is constructed and arranged to cover the outlet opening for final oil removal during refrigerant gas discharge therethrough to the system.
5. The oil separator of claim 3, wherein said secondary mesh liner is constructed and arranged as a downwardly tapering funnel member extending from the primary mesh liner at the upper zone through the intermediate zone and below the gas outlet opening therein.
6. The oil separator of claim 5, wherein the secondary mesh liner is formed as a continuation of the primary mesh liner and functions to accelerate the flow rate of the gas and oil mixture in the downwardly circulating flow path impinging thereagainst for secondary oil separation before discharge of refrigerant gas through the gas outlet.
7. The oil separator of claim 5, in which said tapering funnel member has a large upper end connected to the primary mesh liner adjacent to the upper zone sidewall and has an inwardly narrowed lower end spaced from the sidewall at a lower end of the intermediate zone.
8. The oil separator of claim 7, including a structural support constructed and arranged for supporting the secondary mesh liner.
9. The oil separator of claim 8, in which said structural support comprises a funnel-shaped member connected at its top to the sidewall and underlying the secondary mesh liner.
10. The oil separator of claim 9, in which the funnel-shaped member comprises a framework supporting said secondary mesh liner and having openings therethrough to accommodate the passage of oil from the secondary mesh liner.
11. The oil separator of claim 3, in which said secondary mesh liner is constructed and arranged to extend around the sidewall in the upper zone between the primary mesh liner and the sidewall surface to thereby form a double mesh liner extending vertically from the level of the oil and gas mixture inlet downwardly through the upper zone.
12. The oil separator of claim 11, wherein at least one of said mesh liners extends downwardly through the lower zone of said upper section substantially to said baffle.
13. The oil separator of claim 2, wherein said baffle is constructed and arranged to extend across the oil separator between the upper and lower sections thereof, said baffle having an outer peripheral edge with at least one side portion thereof being spaced away from the sidewall to form an oil passageway to the lower section.
14. The oil separator of claim 13, wherein the baffle has an upper top wall accommodating oil flow outwardly around the peripheral edge and downwardly therefrom through the oil passageway to the lower section.
15. The oil separator of claim 14, including other oil passageways for accommodating oil flow in the lower section.
16. The oil separator of claim 15, in which the top wall of the baffle is upwardly domed and asymmetrically mounted in the oil separator with another side portion being attached to the sidewall to thereby locate the one side portion and the oil passageway opposite thereto.
17. The oil separator of claim 16, in which said other oil passageway comprises ports in the top wall adjacent to said another side portion attached to the sidewall.
18. A vertical oil separator for removing oil from a refrigerant gas and oil mixture on the high side of a refrigeration/chiller system comprising:
- a housing having an upper section forming an oil separation chamber with a cylindrical sidewall and an inlet constructed and arranged for receiving the refrigerant gas and oil mixture from the system compressor and creating a spiraling flow path around said sidewall in the upper chamber, an oil filter device in the oil separation chamber for removing oil particles from the spiraling flow path of the gas and oil mixture, and a gas outlet spaced from the sidewall within the upper chamber for delivering refrigerant gas to the system condenser,
- said housing having a lower section forming an oil receiving chamber below and separated from the upper chamber by a baffle, said lower chamber having an oil outlet therefrom,
- said oil filter device including a first filter associated with the sidewall in said upper chamber for removing oil out of the spiraling flow path of the gas and oil mixture, and other filters constructed and arranged for removing oil from the spiraling flow path upstream of the gas outlet from the upper chamber.
19. The oil separator of claim 18, wherein said upper chamber has upper, intermediate and lower zones, said inlet for the refrigerant gas and oil mixture from the system being disposed in the upper zone and said refrigerant gas outlet being disposed therebelow in the intermediate zone, and said first oil filter comprising a primary mesh liner extending around the sidewall in the upper zone of the upper chamber to thereby perform the primary oil separation function of said oil separator, said other filters comprising a secondary mesh liner constructed and arranged to extend around the sidewall in the upper zone between the primary mesh liner and the sidewall surface to thereby form a double mesh liner extending vertically from the level of the oil and gas mixture inlet downwardly through the upper.
20. The oil separator of claim 18, wherein said baffle is constructed and arranged to extend across the oil separator between the upper and lower chambers thereof, said baffle having an outer peripheral edge with at least one side portion thereof being spaced away from the sidewall to form an oil passageway to the lower chamber, the top wall of the baffle being upwardly domed and asymmetrically mounted in the oil separator with another side portion being attached to the sidewall to thereby locate the one side portion and the oil passageway opposite hereto.
Type: Application
Filed: Mar 2, 2005
Publication Date: Sep 7, 2006
Inventor: Gary Westermeyer (Bluffs, IL)
Application Number: 11/070,595
International Classification: F25B 43/02 (20060101); F25B 43/00 (20060101);