US2046554A - Vapor condensing and liquid cooling apparatus - Google Patents

Description

July 7, 1936. N. H. GAY

VAPOR CONDENSING AND LIQUID COOLING APPARATUS Filed June 21, 1955 5 Sheets- Sheet 1 gwuentoz jl aj a H. m1, MQMMEMMW July 7, 1936. N. H. GAY

VAPOR CONDENSING AND LIQUID COOLING APPARATUS Filed June 21, 1933 3 Sheets-Sheet 2 glwuento'o -m n wm July 7; 1936. H GAY 2,046,554

VAPOR CONDENSING AND LIQUID COOLING APPARATUS Filed June 21, 1933 :5 sheets-sheet 3 gwwzntoc Patented July 7, 1936 VAPOR CONDENSING AND LIQUID COOLING APPARATUS Claims.

This invention relates to apparatus which may be employed for cooling vapors, usually with a precipitation of condensable matter therefrom.

One of the features of the present invention is the provision of a receiving tank with an associated cooling system for cooling vapors entering into the tank or arising from the contents of the tank, with a reflux of the liquid of condensation back into the tank, the tank and cooler being hermetically sealed with respect to one another so that the internal space thereof may be subjected to a pressure reduction with respect to the atmosphere, for example, for accelerating the cooling of liquid present in the tank or in a vessel in communication therewith.

Another feature of the present invention is the provision of a receiving tank in association with a vapor cooler, in which the vapor cooler is provided with a plurality of tubes for the reception of a refrigerant medium which enters the cooling system for employment as a liquid and is withdrawn therefrom as a gas, the tubes being so constructed and arranged as to provide for the separation of refrigerant liquid and gas, and the return of refrigerant liquid for re-passage through certain tubes.

Other features of the invention relate to specific manners of construction, assemblage and association of the parts as will appear in the course of the following description and claims.

Illustrative forms of practicing the invention are set out on the accompanying drawings, in which:

Figure 1 is a conventionalize'd upright section through a receiving tank and its associated vapor cooler, along with a diagrammatic showing of means for supplying refrigerant medium.

Figure 2 is a detail view of a tube sheet,'taken substantially on line 22 of Fig. 1, but on a larger scale, and showing an arrangement of the tubes within the cooler. I

Figure 3 is an upright transverse sectional view of a similar arrangement, taken substantially on line 3-3 of Fig. l, with the inclusion of a modified form of refrigerant liquid supply means.

Figure 4 is. a view corresponding 'to that of Fig. 3, but showing a modification of construction of the'cooler. '1

Figure Sis-a view corresponding to a fragment of Fig. l, and'showinga further modification in the construction of the tank and cooler.

complished through a bottom discharge pipe l3 under the control of a valve l4. In the form illustrated in Fig. 1, the tank is provided with an upper flange to which may be secured and hermetically sealed the flange of a cover dome I5. The top of this cover dome is rigidly connected in tightly sealed relationship with connecting walls It and an inverted U-shaped central piece ll of a cooler structure. It is preferred that this central piece I! shall be of heavier material, usually plate metal, than the other pieces in order to provide ample strength of the structure with a minimum weight of the assembly. Two cooler structure end pieces I8 and I9 are connected to the pieces [6 and H, for example by welding, so that a tightly sealed relationship and assemblage of the parts is produced. It is preferred that these end pieces l8 and [9 shall be cylindrical for a maximum strength against collapse or explosion under vacuum or pressure. At the ends of the pieces I8 and H! are provided the lower header or tube sheet 2!] and the upper header or tube sheet 2|, at the end faces of each of which are provided the domes 22 and 23, furnishing headerspaces for establishing connection between the corresponding ends of the cooler tubes.

'Sealed with and extending between these tube sheets 20 and 2| are a plurality of evaporator tubes 25 which occupy substantially the lower two-thirds of the cross-section of area of the pieces l8 and I9. Near the bottom of these sheets is provided, in similar sealed relationship, a liquid reflux tube 26 which is of much larger diameter, whereby the ratio of peripheral area to volume is less than in the individual tubes 25. At the'top is provided a still larger tube 21 which likewise is sealed with respect to the tube sheets 20 and 2| and serves for the separation of gaseous fron 1 liquid refrigerant for the reflux of liquid refrigerant to the space within the dome 22, and for the maintenance of a level of liquid and/or mixed gaseous and liquid refrigerant above the tubes 25 flows into the receiver R. Fromthe receiver R The compressor C delivers relatively high temperature and at highpressure,

the liquid refrigerant passes by 'a pipe3lthrou I float] 3,4 in a separate float chamber35. As the a shut-off valve 32 to a valve 33 controlled by'a valve 33 opens, liquid refrigerant passes through 1 pipe 36 an d shutoli valve 31 to an inlet pip'e'38 and thus mingles with the other refrigerantpresent in the cooler tubes and headers. 'It will be =un-= derstood that as the'refrigerant enters the cooler through pipe 38,1513. portion of it passed to by which it passes to th'e'space within the dome 22 1 cally sealed with respect to one another.

flash gas at the release of pressure between that existing in receiver R and in the header 22. This gas is separated in large part in the header 22 and passes upward into the upper portion of the tube 21. The liquid level in the float chamber 35 is maintained by the balancing pipes 39 which may be shut off if desired by control valves 40. Further, it is possible to manually control the supply of liquid into the cooler regardless of the float position, by employment of the control valve 4|, possibly with closing of one of the valves 32 or 31. As liquid refrigerant is evaporated in tubes 25 and 26, a mixture of gaseous and liquid refrigerant is produced which is of lesser specific gravity than the liquid refrigerant, and hence tends to move upwardly in these tubes. It will be noted that in Fig. 1 the tubes are shown as having a slight angle upwardly toward the left from the liquid inlet header 22 toward the header 23. An active movement of the liquid'refrigerant is thus produced from the lower or right-hand header 22 of Fig. 1 to the upper or left-hand header 23 of Fig. 1. By reason of evaporation, more and more gas is produced and the movement is accelerated further. On entering the header 23 and passing to the upper tube 21, the gaseous refrigerant separates from the liquid refrigerant and enters the gas return pipe 45 and passes through control valve 46 to the return pipe 41 which leads it back to the compressor C for return in cycle. The liquid refrigerant moves toward the right in the upper tube 21 back to the header 22 and thus reenters the tubes. The large bottom tube 26 operates as a liquid balancing tube between the two headers, irrespective of the operation of the large upper tube 21, and permits a similar liquid reflux while accomplishing also a cooling efiect upon vapors arising from the contents of the tank ID or entering the tank through the conduit l l.

The liquid level is thus constantly maintained. The cooling effect is regulated irrespective of this level by controlling the suction of compressor C upon the refrigerant-evaporating spaces of the cooler,through the action of the valve 46. To establish an automatic regulation, this valve may be opened and closed as by a motor control 50 which is connected by conductors 5| with a source of electrical energy 52 and with a diagrammatically illustrated thermostat 53 exposed to the liquid discharging or ready for discharge from the tank l0. Since this liquid comes from the bottom of the tank, it is the coolest liquid in the tank.

The space surrounding the tubes 25, 26, and 21 is placed in communication through a conduit GI) and a shut-off valve 6| with a suction or vacuum pump.

The operation of this device is as follows:

'The tank and its as'sociatedcooler are hermeti- A fluid is permitted to enter the tank through conduit 1 l. Such a fluid may comprise a mixture of liquid, condensable gas, and non-condensable gas. The gases move upwardly under the suction effect through pipe 60 and come into contact with the tubes 25, 26, and 21. The heat of these gases is then absorbed through the walls of the tubes and produces the aforesaid evaporation of the liquid refrigerant. The gases are themselves cooled and the condensable portions are reduced to liquid and reflux back into the tank It). Further, the evacuating effect through the pipe 60 reduces the pressure within the tank I0 so that the liquid therein boils at a lower temperature. The liquid is thus cooled directly by such boiling, and the vapors evolved are condensed and refluxed back l6 and a U-shaped piece I! as in Fig. 1, with the arrangement of the tubes 25, 26 and 21, but. in this form a replenishing supply of liquid refrigerant is introduced through a pipe 380., past a manually adjustable expansion valve 4la, while the supply may be shut off independently of the adjustment of the valve 4 I a by closing a stop valve Mb. The operation of this structure with respect to the condensation and reflux of the contents of tank I0 is the same as before.

In the form shown in Fig. 4, walls IBa are carried upwardly from the upper flanges of tank l0 and join tangentially the upper closing walls Ila and Nb of two separate evaporator structures. One of these structures is illustrated as being larger than the other and having a greater number of tubes 25. This left-hand larger cooler is shown as having the accumulating and separating tube 21 and the lower liquid balancing tube 26, as in the forms of Figs. 1 and 3. The right- 1 hand smaller cooler has an upper accumulating and separating tube. 21 but no lower balancing tube 26, as this latter is unnecessary in some instances. It is, however, provided with the normal evaporating tubes 25. By this employment of a greater cross-section of structure, the overall length of the tubes between tube sheets such as 20 and 2| of Fig. 1 may be reduced, and the total length of the tubes restricted substantially to the diametrical dimension of the tank I 0. ploying a plurality of separate coolers, each individual cooler contains the parts necessary for its independent operation and hence the cooling effects may be regulated as desired by controlling the independent valves 46a and 4617. Further, the particular construction shown makes it possible to employ cylindrical end sections such as l8 and l9'of smaller diameter than would be the case were a single cylindrical unit provided, with a consequent gain in the strength of each member for the given thickness of wall. Further, the arrangement shown in Fig. 4 has the advantage of providing a suificient number of tubes in a vertical direction for the adequate cooling of the vapors and gases from the tank ill, but without requiring unnecessarily large diameters of cooler structures for attaining a sufiicient number of sets of tubes in a horizontal direction for handling the desired volume of gases and vapors.

In the particular forms shown, the cooler is sub- 5 However, these specific forms of construction are not essential to the practicing of the present invention which may also be varied in many ways without departing from the scope of the appended claims.

Having thus described the invention, what I claim as new and desire to secure by Letters Patent, is:

1. An apparatus for cooling a liquid, comprising a tank for liquid, a plurality of substantially horizontal tubes externally exposed to vapor in By emsaid tank, means for supplying liquid refrigerant to the interior of said tubes, means for separating gaseous and liquid refrigerant issuing from said tubes and for returning liquid refrigerant to said supplying means, means for withdrawing the gaseous refrigerant and reducing it to liquid refrigerant and returning the same to said supply means, means for controlling the evaporation in said tubes, said tubes being positioned for the reflux of condensed liquid condensed externally thereon to the bottom of said tank for cooling the liquid therein, a thermostat exposed to the liquid in said tank, and control means for operatively connecting said thermostat and evaporation control means.

2. An apparatus for cooling a liquid, comprising a tank for liquid, a. plurality of tubes extennally exposed to vapor in said tank, means for supplying liquid refrigerant to the interior of the tubes and including refrigerant inlet and outlet headers, some of said tubes being evaporator tubes in which the refrigerant flows from the inlet to the outlet header and is partially evaporated therein and at least one of the tubes being an accumulator tube larger than any said evaporator tube and extending between said headers for the separation of gaseous and liquid refrigerant and operating to return liquid refrigerant from the outlet to the inlet header, and means for withdrawing gaseous refrigerant.

3. An apparatus for cooling a liquid as in claim 2, in which said evaporator tubes have a slight continuous upward inclination from the inlet to the outlet header to promote movement of the refrigerant in the evaporator tubes from inlet to outlet headers and of liquid refrigerant in said large accumulator tube from outlet to inlet headers.

4. An apparatus for cooling a liquid as in claim 2, in which the tank has a large mouth and the tubes are enclosed in a cooler structure having a large lower opening and separable from said tank and scalable to the tank for closing said mouth.

5. An apparatus for cooling a liquid, comprising a tank for liquid, a plurality of evaporator tubes located above the liquid in the tank for refluxing thereto, a structure for establishing an hermetic seal around said tubes and closing said tank, including a semi-cylindrical top portion and laterally projecting cylindrical portions coaxial and of substantially the same diameter as said semi-cylindrical portion, inlet and outlet header means on said cylindrical portions, the evaporator tubes extending between said header means and being located insaid semi cylindrical and cylindrical portions and extending across said tank, means for evacuating said tank whereby to draw vapor from the liquid in the tank to provoke a cooling thereof by evaporation, said tubes operating to condense liquid from the vapor and reflux the same into said tank for further cooling of said liquid, and means for supplying liquid refrigerant into said tubes and withdrawing gaseous refrigerant therefrom.

6. An apparatus for cooling a liquid, comprising a, tank for liquid, refrigerant inlet and outlet headers attached to said tank, a plurality of evaporator tubes extending between said headers, an accumulator tube extending between said headers above said evaporator tubes and operating for the free movement of gas from the inlet to the outlet header and free movement of liquid from the outlet to the inlet header, means for supplying liquid refrigerant to and withdrawing gaseous refrigerant from said headers and including a liquid level control device for maintaining a liquid level in said accumulator tube, and a cover cooperating with said headers for hermetically closing said tank and enclosing said tubes. 7. An apparatus for cooling liquid comprising a tank for liquid, a plurality of juxtaposed semicylindrical casings which are connected and together close the said top opening and afford free access for vapor in the tank to pass into said casings, means included in the casings for providing pairs of independent inlet and outlet headers, said pairs being horizontally spaced from one another, pluralities of evaporator tubes extending across the tank between pairs of said headers, an accumulator tube in each pair extending between the headers of each such pair at a predetermined liquid level in said outlet and inlet headers of the pair whereby to provide for free passage of liquid refrigerant from the outlet to the inlet headers and free passage of gas from the inlet to the outlet headers independently of the evaporator tubes, and means for supplying liquid refrigerant to and withdrawing gaseous refrigerant from said headers and tubes. 8. An apparatus for cooling a liquid as in claim 7, including means for evacuating said tank and operative for drawing vapors over said tubes, and means for controlling the drawing of such vapors over the tubes of at least one pair of headers.

9. An apparatus for cooling liquids comprising a tank and closure means therefor providing a sealed chamber, aligned laterally projecting cylindrical portions sealed to and located at opposite parts of the chamber above a predetermined liquid level therein, inlet and outlet header structures mounted at the outer ends of the cylindrical portions, a plurality of evaporator tubes extending between said header structures and through said chamber, and an accumulator tube of larger diameter than the evaporator tubes and also extending between said header structures and through said chamber to afford passage for gas from the inlet toward the outlet header and for liquid from the outlet toward the inlet header.

10. Apparatus for cooling a liquid and separating non-condensable gases therefrom, comprising a tank for receiving the liquid, closure means for sealing the tank, cooling ducts and an accumulator duct located within the vapor space provided by said tank and closure means and above the liquid level in the tank for maintaining at least the upper portion of the said vapor space at a temperature below the condensation point of the liquid and so constructed and arranged that condensed liquid flows back into the body of the liquid in the tank for cooling the same, inlet and outlet headers connecting said ducts, means for delivering liquid refrigerant to said headers and withdrawing gaseous refrigerant from said outlet header, said accumulator duct being constructed and arranged for separating gaseous and liquid refrigerant and returning the liquid refrigerant to the inlet header, means for delivering hot liquid into said tank, means for drawing off non-condensable gas from said cold upper portion and therewith reducing the vapor pressure at the surface of the liquid, and means for withdrawing liquid from the bottom of said tank.

NORMAN H. GAY.

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