US2092067A - Chilling apparatus - Google Patents

Description

P 7, 937. N. H. HILLER 2,092,067

CHILLING APPARATUS Filed'May 6. 1954 s shuts-sheet 1 ill II I

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fiiiii l Q Ill INVENTOR 5 75 WMEM'JM .aELe-W .34 4 w w aw- 5 ATTORNEYS,.

p 1937. N. HQHILLER CHILLING APPARATUS Filed May 16, 1934 3 Sheets-Sheet 2 INVENTOR Mbou'lZ/Ya'ller BY 494M JAJMQ'M ATTORNEYS Sept 7, 1937. F L 2,092,067

CHILLING APPARATUS Filed May 16, 1954 s sheets-sheet s ATTORNEYS Patented Sept. 7, 1937 UNITED STATES PATENT OFFICE CHILLING APPARATUS poration of Virginia Application May 16, 1934, Serial No. 725,889

17 Claims.

My present invention considered from its broader aspects is concerned generally with heat interchangers and particularlywith the problem of controlling the supply and distribution of a volatile refrigerant to a heat interchanger.

More specifically the invention relates to an apparatus for chilling distillates to separate out, by a process of congelation, paraffin, wax or the like, and represents an improvement over the No. 922,898 and in my Patent No. 2,039,796, filed October 31, 1933. This type of apparatus customarily includes one or moreseries of horizontally disposed pipes arranged at different levels and through which the material to be chilled is circulated. These pipes are suitably jacketed to provide evaporator chambers, and means is provided for circulating a volatile refrigerant through the jackets or evaporators.

An object of the invention is to eliminate the need for a refrigerant circulating pump with the consequent elimination of packings and stuffing boxes as well to avoid the expense of providing motive power for such a pump.

Another object of the present invention is to insure the delivery of the proper amount of refrigerant to the jackets which are located at various levels and to provide a system which is self-regulating. That is to say I provide a system which is balanced in the sense that chilling of the liquid is carried on during the entire time that the liquid is passing through the jacketed pipes. Merely suflicient refrigerant is supplied and sufllcient cooling done in any one jacket to assure uniform and complete treatment of the liquid regardless of the temperature at which the liquid enters the heat interchanger. The apparatus is efllcient in that no excess of refrigerant is circulated yet it is self-regulating to in- 40 sure the supply of an adequate amount of refrigerant in each jacket, and to automatically vary the supply when a change in the temperature of the distillate requires such variation.

45 In a preferred form of the invention the flow of liquid refrigerant to the jackets is regulated heat interchangers shown in the Hiller Patent are all freely connected so that similar liquid levels are maintained therein.

With this type of apparatus, flooding of the jackets with an excess of refrigerant will increase the liquid level in the lowermost jacket and in the accumulator and float chamber, and cut ofi further delivery of refrigerant to the upper jackets with the'result that a condition of balance will quickly be established where only the proper amount of liquid refrigerant is being delivered to effect substantially uniform chilling of all the sections of the distillate line regardless of the elevation of such sections.

In accordance with one embodiment of the invention the liquid refrigerant passes through metering orifices and through a number of the upper jackets in parallel, the residual liquid finding its way by gravity into the lowermost jackets. Whether the jackets be series-connected or parallel-connected, the lowermost jacket is still supplied by the residue of liquid which has passed through the jackets above it and the system rapidly establishes and maintains a definite balance and a definite and correct circulation of refrigerant.

The invention may be more fully understood from the following description in connection with the accompanying drawings wherein:

Fig. 1 is a broken side elevational view of a chilling apparatus embodying the invention with parts of the jackets broken away to expose the coils of the distillate line,

Fig. 2 is a vertical sectional view taken approximately on the line 2-2 of Fig. 1,

Fig. 3 is an enlarged sectional detail of one of the metering orifices,

Fig. 4 is a top plan view of a modified form of apparatus,

1 Fig. 5 is a side elevational view of the apparatus shown in Fig. 4,

Fig. 6 is a vertical sectional view on the line 66 of Fig. 5,

. Fig. '7 is a vertical sectional view on the line i--'i of Fig. 6, and

Fig. 8 is an enlarged transverse detail on the line 8--8 of Fig. "I.

Referring first to Figs. 1 to 3 of the drawings I have used the reference letters A, B, C, D, E and F to designate six horizontal coils or pipe sections arranged in superposed relationship and each comprising a plurality of pipes II] which serve to conduct the liquid to be treated, typically a distillate from which parafiln or wax is to be separated out by chilling. The pipes of each set are connected together as by the horizontal bends l I,

7 as follows:

and one pipe. of each is connected to a pipe of the next lower set by vertical bends l2.

pipe sets, residual liquid and evolved gases passing into the stand pipe 22- from which the liquid The various pipe sets may, be supported by a drains into the accumulator and from which the suitable skeleton framework including a plurality of standards l3 connected by pipe supporting bolts l4. As is customary in such apparatus, means is provided for scraping the-paraflin from the walls of the pipes I 0 so that it may be washed along by the flowing liquid stream, such means 10 typically comprising spiral scrapers I5 mounted upon shafts 16 which extend longitudinally of the pipes Ill. The projecting ends ofthese shafts may have bearings in castings l1 and allof the conveyers may be driven from a motor l8 actu- 15 ating a chain l9 which is engaged with sprocket wheels l9a on the ends of the shafts l6. These scrapers or conveyors maybe of the type disclosed more fully in the Torrance Patent No. 1,796,772 issued March 17, 1931.

t The horizontal portion of each pipe 10 is encased in ajacket 20 through which the refrigerant is circulated to properly chill the contents of the pipes l0.-

-A vertically disposed header 2| from which I liquid refrigerant is supplied to the jackets: 20 is arranged atone side of the sets of pipes A, B,

C, etc. and directly opposite this header is a'vertical return pipe- 22 for refrigerant which delivers into an accumulator 23. The five uppermost pipe sets A, B, C, D and E are connected to each other, to the header 2| and to the return pipe 22 by cross pipes 20a, but the lowermost pipe set F has no djrectconnection with either the header 2| or 'the pipe 22.

' This lowermost pipe setis disposed at the same level as the accumulator 23 and similar liq uid levels are maintained in the jackets of thelowermost pipe set and in the accumulator by means of a pipe 24 connecting the-bottom of one jacket to the bottom of the accumulator, a pipe 25 connecting the top of the other jacket to the top of the accumulator and cross pipe 26 which directly connects the jackets of the lowermost pipe set F.

A conventional float. chamber 21 is also disposed at the same level as the accumulator and the liquid level in this chamber controlled by the liquid level in the accumulator and lower set of jackets, the accumulator and float chamber communicating with each other through the pipes 28 50 and 29.

65 a pipe 3| which leads to the bottom of the header 2|. Each of the pipes 20a near its inlet end is provided with a metering device such for instance as the disk 32 of Fig. 3, having a metering orifice 33 therein so that an equal amount of 60 refrigerant is delivered to each of the parallelconnected jackets or evaporators.

Beneath the accumulator 23 is a tank 34 having a valve 35 therein through which the system may be drained. The gases which are evolved 'in the jackets 20 are withdrawn from the accumulator through a pipe 36 and reliquefled, and the liquid may be redelivered through the pipe 30 at the condenser pressure of the system.

The operation of this system is substantially 7 orifices 33 into the jacket: of the five uppermost the jackets of the upper pipe sets.

gases are withdrawn through the pipe 36. As the liquid level builds up in the accumulator, liquid will fiow into the jackets of the lowermost pipe set F and will flow into the float chamber 21 and when this level reaches a suflicient height, .the valve controllingthe flow from the pipe 30 will be shut off. Particular attention is called to the manner in which the system rapidly reaches a balanced condition for any given temperature of liquid to be treated, whereby all of the jackets or evaporators aid in the cooling and solid separating operation.

Assuming that suflicient liquid has passed through the, system to partially flll the accumulator and the jackets of the lowermostpipe set,

it will be apparent that the float valve will be.

immediately cut off and will remain cut off until such time as gas evolution in the various jackets including the jackets of the lowermost pipeset has reduced the level in the accumulator. upon more liquid refrigerant will be admitted past the float controlled valve. If there is over-refrigeration or an excess of cooling in the upper pipe sets there will be little gas evolution in the jackets of the lowermost pipe set and consequently little variation in the liquid level in the accumulator which would permit the float valve to open. Thus the heat of the liquid passing through the lowermost set of jacketed pipes is the real control factor which regulates the admission of refrigerant to the other jackets and consequent chilling of the liquid in advance of the time that it reaches the lowermost set of pipes. ature of the liquid which is admitted to the apparatus for treatment,'the apparatus soon reaches 'a state of balance where there will be a more or less steady fluttering or cracking of the float controlled valve which admits refrigerant, with the result that the liquid leaving the system after treatment will be uniformly cooled. 1

In Figs. 4 to 8 inclusive I have illustrated a somewhat similar system but in which the volatile refrigerant flows through all of the jackets in series rather than flowing in parallel through Similar reference numerals have been retained in these fig ures for similar parts and the framework struc- There- In operation, regardless of the temperture and drive means for scraper shafts have been omitted for thesake of clarity.

With this form of the invention, the float chamber 21 communicates freely with an accumulator 41 through the pipes 42 and 43 and the float valve controls the passage of liquid refrigerant from the supply pipe 30 through a riser 44 into the jacket 20 of the uppermost pipe set. The two jackets of this pipe set are connected by a pipe 45 and the evolved gases together with the residual liquid are led from the top of the last jacket of the series through a pipe 46 into a stand pipe 41 which communicates freely with the top of the accumulator, this stand pipe connecting at its top with an outlet pipe 48 throughv which the evolved gases are withdrawn.-

The residual liquid entering the stand pipe from the pipe 48 and the pipe 46 drains into a trap 49 open at its top to permit the escape of gases and communicating at its bottom with a pipe 50 which leads to the jackets 20 of the pipe set B, these jackets being connected by pipe 45 and the gases and residual liquid from the last jacket of theseries passing off through an overpipe sets, the evolved gases in each case bein drawn ofi from the top of the stand pipe 41. Again however the jackets for the lowermost pipe set communicate directly with the accumulator 4|, the jackets themselves being connected by pipe 5|, the first jacket of the set communicating with the lower portion of the accumulator through pipe 52 and the last jacket of the set communicating with the upper portion of the-accumulator through a pipe 53.

Thus the opening and the closing of the float valve is, in the final analysis, controlled by the level of the liquid in the jackets of the lowermost pipe set and again this liquid cannot build up to a position to close the float valve until such time as sufficient liquid has traversed all of the upper jackets and found its way into the accumulator. This system, like the system of Figs. 1 to 3, is quickly self-balancing or self-regulating and a condition is quickly reached where a more or less uniform flow of liquid refrigerant depending upon particular cooling requirements of the liquid being treated, will be steadily delivered past the float controlled valves. Here again a certain amount of cooling is effected by each jacket since there can be no ebullition in the lowermost jacket if the liquid being treated has been over-chilled in the upper jackets and consequently no flow of refrigerant until such time as the liquid reaches the lower jacket in a sufficiently warm condition to cause cbullition of the refrigerant therein.

It will be apparent that the particular number of pipes I0 in each pipe set is subject to a wide range of variation and that any suitable number of superimposed pipe sets with their encasing jackets or evaporators might be employed. Both systems are characterized by a freedom from gas traps which might exert undesirable back pressure on the liquid refrigerant. In each system the temperature of the liquid being treated as it passes through the last and lowermost evaporator or set of jackets, is the ultimate controlling factor for the admission of refrigerant to the other jackets.

WhileI have illustrated two typical embodiments of the invention, various changes and alterations might be made without departing from the spirit of the invention or the scope of the appended claims.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is:-

1. A heat interchanger including a plurality' of vertically spaced horizontal pipe sections for conducting liquid to be treated, a plurality of evaporator sections arranged at different levels in heat exchange relationship with the respective pipe sections, an accumulator arranged at the level of the lowermost evaporator section, a float valve controlling chamber arranged at the level of the lowermost evaporator section, said accumulator, valve chamber and lowermost evaporator section communicating freely so that the liquid in them is maintained at a common level,

conducting liquid to be treated, a plurality ofevaporator sections arranged in heat exchange relationship with the respective pipe sections, an accumulator arranged at the level of the lower most evaporator section, a float valve controlling chamber arranged at the level of the lowermost evaporator section, said accumulator, valve controlling chamber and lowermost evaporator section communicating freely so that the liquid in them is maintained at a common level, and means controlled by the float valve for delivering a volatile liquid refrigerant to the upper evaporator sections, said lowermost evaporator section receiving only residual liquid from the upper evaporator sections through said accumulator.

3. A heat interchanger including a plurality of vertically spaced horizontal pipe sections for con ducting liquid to be treated, a plurality of evaporator sections arranged at different levels in heat exchange relationship with the respective pipe sections, an accumulator arranged at the level of the lowermost evaporator section, a float valve controlling chamber arranged at the level of the lowermost evaporator section, said accumulator, valve chamber and lowermost evaporator section communicating freely so that the liquid in them is maintained at a common level, means controlled by the float valve for delivering a volatile liquid refrigerant to the upper evaporator sections, a vertically disposed inlet header into which refrigerant passing the float controlled valve is delivered, a plurality of pipes through which liquid from the header flows in parallel to the upper evaporator sections, means for metering the flow of liquid to saidsections, and a stand pipe constituting a return header through which the evolved gases and residual liquid from the upper evaporator sections pass to the accumulator.

4. A heat interchanger including a plurality of vertically spaced horizontal pipe sections for conducting liquid to be treated, a plurality of evaporator sections arranged in heat exchange relationship with the respective pipe sections, an accumulator arranged at the level of the lowermost evaporator section, a float valve controlling chamber arranged at the level of the lowermost evaporator section, said accumulator, valve controlling chamber and lowermost evaporator section communicating freely so that the liquid in them is maintained at a common level, means controlled by the float valve for delivering a volatile liquid refrigerant to the upper evaporator sections, said lowermost evaporator section receiving only residual liquid from the upper evaporator sections, a vertically disposed inlet header into which refrigerant passing the float controlled valve is delivered, a plurality of pipes through which liquid from the header flows in parallel to the upper evaporator sections, means formetering the flow of liquid to said sections, and a stand pipe constituting a return header through which the evolved gases and residual liquid from the upper evaporator sections pass to the accumulator.

5. A heat interchanger including a plurality of vertically spaced horizontal pipe sections for conducting liquid to be treated, a plurality of evaporator sections arranged in heat exchange relationship with the respective pipe sections, an

accumulator arranged at the level of the lower-' most evaporator section, a float valve controlling chamber arranged at the level of the lowermost .maintained at a common level, and means controlled by the float valve for delivering a volatile liquid refrigerant to the upper evaporator sections, said lowermost evaporator section, accumulator and float valve controlling chamber receiving liquid only from the upper evaporator sections, a stand pipe rising from the accumulator and receiving evolved refrigerant gases from all of the upper evaporator sections, a vertically disposed inlet header into which refrigerant passing the float controlled valve is delivered, a plurality of pipes through which liquid from the header flows in parallel to the upper evaporator sections, and means for metering the flow of liquid to said sections, said stand pipe constituting a return header through which the evolved gases and residual liquid from the upper evaporator sections pass to the accumulator.

6. A heat interchanger including a plurality of vertically spaced horizontal pipe sections for conducting liquid to be treated, a plurality of evaporator sections arranged in heat exchange relationship with the respective pipe sections, an accumulator arranged at the level of the lowermostevaporator section, a float valve controlling ,chamber arranged at the level of the lowermost evaporator section, said accumulator, valve controlling chamber and lowermost evaporator section communicating freely so that the liquid in them is maintained at a common level, means controlled by the-float valve for delivering a volatile liquid refrigerant to the upper evaporator sections, said lowermost evaporator section receiving only residual liquid from the upper evaporator sections, a pipe for conducting liquid refrigerant which passes the float controlled valve into the uppermost evaporator section, and means connecting all of theevaporator sections above the lowermost ones in series, whereby residual liquid from an upper section passes into a subjacent one, said connecting means including a J plurality of open-topped liquid receiving pockets arranged at different levels in the stand pipe whereby the gases evolved at each evaporator, escape from the pockets and the residual liquid flows to a subjacent evaporator section.

- 7 A heat interchanger including a plurality of vertically spaced horizontal pipe sections for conducting liquid to be treated, a plurality of evaporator sections arranged in heat exchange relationship with the' respective pipe sections, an

accumulator arranged at the level of the lowermost evaporator section, a float valve controlling chamber arranged at the level of the lowermost evaporator section, said accumulator, valve chamber and lowermost evaporator section communicating freely so that the liquid in them is maintained at a common level, means controlled by the float valve for delivering a'volatile liquid refrigerant to the upper evaporator sections, said lowermost evaporator section, accumulator and float valve controlling chamber receiving liquid only from the upper evaporator sections, a stand pipe rising from the accumulator and receiving 4 evolvedrefrigerant gases from all of the upper evaporator sections, a pipe for conducting liquid refrigerant which passes the float controlled valve into the uppermost evaporator section, -means' connecting all of the evaporator sections above the lowermost ones in series, whereby residual liquid from an upper section passes into a subjacent one, and a plurality of open-topped liquid receiving pockets arranged at different levels in the stand pipe whereby the gases evolved at each evaporator, escape from the pockets and the residual liquid flows to a subjacent evaporator section.

8. A heat interchanger including a plurality of vertically spaced horizontal pipe sections for conducting liquid to be treated, a plurality of evaporator sections arranged in heat exchange relationship with the respective pipe sections, an

accumulator arranged at the level of the lowermost evaporator section, a float valve controlling chamber arranged at the level of the lowermost evaporator section, said accumulator, valve chamber and lowermost evaporator section communicating freely so that the liquid in them is maintained at a common le'vel, means controlled by the float valve for delivering a volatile liquid refrigerant to the upper evaporator sections, said lowermost evaporator section, accumulator and float valve controlling chamber receiving liquid only from the upper evaporator sections, a stand pipe rising from the accumulator and receiving evolved refrigerant gases from all of the upper evaporator sections, and means for withdrawing gases from the top of the stand pipe.

9. A heat interchanger including a plurality of vertically spaced horizontal pipe sections for conducting liquid to be treated, a plurality of evaporator sections arranged in heat exchange relationship with the respective pipe sections, an accumulator arranged at the level of the lowermost evaporator section, a float valve controlling chamber arranged at the level of the lowermost evapo rator section, said accumulator, valve chamber and lowermost evaporator section communicating freely so that the liquid in. them is maintained at a common level, means controlled by the float valve for delivering a volatile liquid refrigerant to the upper evaporator sections, said lowermost evaporator section, accumulator and float valve controlling chamber receiving liquid only from the upper evaporator'sections, a stand pipe rising from the accumulator and receiving evolved refrigerant gases from all of the upper evaporator sections, said evaporator sections comprising jackets encircling the sections of the liquid conducting pipe line. 6

10. A heat interchanger including a plurality of vertically spaced horizontal pipe sections for conducting liquid to be treated, a plurality of evaporator sections arranged at different levels in heat exchange relationship with the respective pipe sections, a float valve controlling chamber arranged at the level of the lowermost evaporator section, said valve controlling chamber and lowermost evaporator section communicating freely so that the liquid in them is maintained at a common level, and means controlled by the float valve for delivering a volatile liquid refrigerant to the upper evaporator sections, said lowermost evaporator section receiving only residual liquid 1 from the upper evaporator sections through said accumulator.

11. In a heat interchanger including a plurality I of horizontal pipe sections for conducting liquid to be treated and arranged in vertical tiers, evaporator sections arranged in heat exchange relationship with said pipe sections, an accumulator, a stand pipe receiving liquid refrigerant from certain of said evaporator sections and'delivering it to said accumulator, the lowermost tier of said evaporator sections receiving liquid refrigerant from said accumulator, and means controlled by the level of liquid refrigerant in said lowermost tier and said accumulator for controlling delivery of liquid refrigerant to the evaporator sections of the upper tiers.

12. In a heat interchanger including a plurality of horizontal pipe'sections for conducting liquid to be treated and arranged in vertical tiers, evapo-T rator sections arranged in heat exchange relationship with said pipe sections, a stand pipe receiving liquid refrigerant from certain of said evaporator sections, the lowermost tier of said evaporator sections receiving liquid refrigerant only from said upper tiers through said stand pipe, and a float valve controlled by refrigerant liquid level in said lowermost tier for controlling delivery of liquid refrigerant to the evaporator sections of the upper tiers.

13. In a heat interchanger including a plurality of horizontal pipe sections for conducting liquid to be treated and arranged in vertical tiers, evaporator sections arranged in heat exchange relationship with said pipe sections, a stand pipe receiving liquid refrigerant from certain of said evaporator sections, the lowermost tier of said evaporator sections receiving liquid refrigerant only from said upper tiers through said stand pipe, a delivery pipe for delivering liquid refrigerant to the evaporator sections in the upper tiers, and a float valve controlled byliquid refrigerant level in the lowermost tier for controlling the delivery of liquid refrigerant through said delivery pipe.

14. In a heat interchanger including a plurality of pipe sections for conducting liquid to be treated and arranged in vertical tiers, evaporator sections arranged in heat exchange relationship with said pipe sections, an accumulator, a stand pipe receiving liquid refrigerant from the upper tiers of said evaporator sections and delivering it to said accumulator, a delivery pipe for delivering liquid refrigerant to said evaporator sections in said upper tiers, the lower most tier of said evaporator sections receiving liquid refrigerant only from said accumulator, and means controlled by the level of liquid refrigerant in said lowermost tier and said accumulator for controlling the delivery of liquid refrigerant through said delivery pipe.

15. In a heat interchanger including a plurality of pipe sections for conducting liquid to be treated and arranged in vertical tiers, evaporator sections arranged in heat exchange relationship with said pipe sections, an accumulator, a stand pipe receiving liquid refrigerant from the upper tiers of said evaporator sections and delivering it to said accumulator, a delvery pipe for delivering liquid refrigerant to said evaporator sections in said upper tiers, the lowermost tier of-said evaporator sections receiving liquid refrigerant only from said accumulator, and a float valve controlled by the level of liquid refrigerant in said accumulator for controlling the delivery of liquid refrigerant through said delivery pipe.

16. In a heat interchanger including a plurality of pipe sections for conducting liquid to be treated and arranged in vertical tiers, evaporator sections arranged in heat exchange relationship with said pipe sections, an accumulator, a stand pipe receiving liquid refrigerant from the upper tiers of said evaporator sections and delivering it to said accumulator, a delivery pipe for delivering liquid refrigerant to said evaporator sections in said upper tiers, the lowermost tier of said evaporator sections receiving liquid refrigerant only from said accumulator, and a float valve controlled by the level of liquid refrigerant in said accumulator for controlling the delivery of liquid refrigerant through said delivery pipe, said delivery pipe having through delivery connection with the evaporator sections in each of the tiers above the lowermost tier.

17. In a heat interchanger including a plurality of pipe sections for conducting liquid to be treated and arranged in vertical tiers, evaporator sections arranged in heat exchange relationship with said pipe sections, an accumulator, a stand pipe receiving liquid refrigerant from the upper tiers of said evaporator sections and delivering it to said accumulator, a delivery pipe for. delivering liquid refrigerant to said evaporator sections in said upper tiers, the lowermost tier of said evaporator sections receiving liquid refrigerant only from said accumulator, and a float valve controlled by the level of liquid refrigerant in said accumulator for controlling the delivery of liquid refrigerant through said delivery pipe, said delivery pipe having through delivery connection with the evaporator sections in each of the tiers above the lowermost tier, and means for metering the flow of liquid from said delivery pipe to said evaporator sections.

NICOLAI H. HILLER.

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