US2362539A - Rotary water-cooled tube cooler - Google Patents

Description

Nov. 14, 1944. R. D. CHEESMAN ROTARY WATER-COOLED TUBE COOLER 2 Sheets-Sheet 1 Filed July 21, 1942 192454726]. 6&6 s a 1944. R. D. CHEESMAN ROTARY WATER-COOLED TUBE COOLER Filed July 21, 1942 2 SheatS-Sheet 2 Patented Nov. 14, 1944 ROTARY WATER-COOLED TUBE COOLER 7 Richard D. Cheesman, Allentown, Pa assignor to Traylor Engineering and Manufacturing Company, Allentown, Pa., a corporation of Delaware Application July 21, 1942, Serial No. 451,778

M 8 Claims.

This invention relates to improvementsin rotary tube coolers of the type'disclosed in the copending patent application of-R. S, Walker, F. A. Mertz and R. R. Shafter, Serial No. 444,736. In coolers of this-type the material to be cooled is continuously passedthrough a series of'relatively thin-walled muffle tubes supported in header plates adapted to rotate about a generally horizontal axis. The tubes desirably are air-cooled throughout a portion of their length and watercooled for another portion of their length. Such coolers are efiicient in operation and are especially suitable for-thecooling of materials, such as lime, which must be maintained out of contact with the atmosphere to prevent air slaking such as would impair the quality of the product.

An important object of the invention is to pro; vide a rotary water-cooled tube cooler of he above character in which the air-cooled portion of the mufile tubes is enclosed within a housing, for example a cylindrical drum, through which a stream of cooling air is passed, and the watercooled portion of the tubes located beyond the end of the housing is exposed to awater spray to further promote the cooling of the material,

In the preferred form of the invention, air is introduced into the housing under pressure through an intake conduit opening centrally through the back header plate and removed from the housing through an o-fftake conduit opening through the front headerplate; The intake conduit is preferably extended axially through the water-cooled zone of the cooler and exposed to the water spray for lure-cooling the air prior to its introduction into the housing.

Another object of the invention is to provide in a rotary water led tube'cooler of the above character, means for water-cooling the muflle tubes in a zone located beyond the housing and op n to the atmosphere so that outside air is free to circulate into contact with the wet tubes and increase by evaporation the cooling of the tubes.

Still another. object of the invention isto provide a combined air-and-water cooled tube cooler of compact, simple and rugged construction, in which the drum forming the housing about the tubes sustains the greater part of the weight of the apparatus, while the tubes extending beyond the drum are relieved of anyappreciable stress.

Other objects and advantages will be apparent from the following detailed description of a preferred embodiment of the invention, reference being had to the-annexed drawings in which:

Figure 1 is a'view in sideelevation of a rotary tube cooler having a housing enclosing the tubes for a portion of their length and forming an aircooled section, and a water spray for cooling the tubes extending beyond the housing;

Figure 2 is a longitudinal cross-sectional view of the cooler of Fig. 1 shown on a slightly larger scale and having an intermediate portion omitter;

Figure 3 is atransverse cross-sectional view of the forward end of the cooler taken on the line 33 of Fig.2; a v Figure 4 is a transverse cross-sectional View of the cooler taken on the line 4--4 of Fig. 2;

Figure 5 is a transverse cross-sectional view of the cooler taken on the line 55 of Fig, 2;

Figure 6 is a detail view of the seal between the discharge end of a blower and the end of the in take conduit for delivering air into the housing;

and

Figure 7 is a schematic vertical cross-sectional view of a modified form of the cooler.

In the drawings is shown a form of rotary tube cooler suitable forthe cooling of lime and cement clinker. The cooler comprises a series of cire cularly-arranged laterally-spaced apart muflle tubes I supported at their forward ends in a front header plate 2, at' points. adjacent their midlength in an intermediate header plate 3, and at their rear ends in a rear header plate 4. The

tubes extend generally horizontally but at a Slight? inclination from their forward ends downwardly toward their rear ends. That portion of the tubes between the front and intermediate header plates is enclosed within a cylindrical drum 5 of relatively thick metal plate welded or otherwise secured to these header plates so as to form therewith a-closed housing serving as an air-cooling chamber.

Within the drum located at spaced intervals lengthwise thereof area series of alternately arranged baflles 6 and. 6a. The baffles 6 are each of generally disk shape and so formed as to seat upon and besupported by the circular ring of tubes; while'the baffles Ba are each of annular shape and provided with *openings for passing the tubes, the enlarged central opening 61) allowing the flow of air therepast. The function of muffle tubes.

arily supported by upright posts 2! footing on the front header plate 2 to provide a closed compartment in advance of the tubes in which is secured a generally cylindrical casting 1' having radial wings la located adjacent the inlet ends of the tubes for directing material into the tubes during rotation of the cooler. The material to be cooled is discharged into the compartment from an inclined spout 8 communicating at its upper end with a hopper 9 associated with a hood l closing the discharge end of a rotary kiln II, The forward end of the drum is closed by a ring shaped cover plate l2 welded to the drum and having a comparatively large central opening which is closed by an annular closure member l3 exteriorly overlying the cover plate and including a hollow boss I3a projecting into the opening. The closure member is supported upon the upper ends of a pair of stanchions I4 pivotally connected at their lower ends to anchor blocks l5. By removing the spout 8 and swinging the stanchions on their anchor blocks, the closure member l3 may be moved into or out of closing position with respect to the centralppening in cover I2.

The muffle tubes l between theintermediate header plate 3 and the rear header plate 4 are open to the atmosphere and extending above these tubes are two water spray pipes is arranged in parallel and connected with a source of water supply. These pipes are formed with orifices ll for directing jets of cooling Water downwardly upon the tubes, as best indicated in Fig. 5. The header plates 3 and 4 upon their circumferences are provided with guards I8 flared in opposite directions (see Figs. 1 and 2) so as to confine the jets to the water-cooled zone of the cooler. Adjacent the rear header 4 and directed rearwardly therefrom is an annular dish-shaped casting l9 having its rim |9a directed rearwardly and telescoping over the inner end of a cylindrical discharge casing to which it is fixed, this casing forming a closed compartment for receiving the material issuing from the ends of the The discharge casing is stationfoundation blocks 22. A discharge chute 23 leadingoif from the lower side of the discharge casing directs the cooled material onto a conveyor, indicated conventionally at C.. The chute is closed by a weighted flap valve V against the entrance of air into the casing but yields to permit the passage of material out through the chute.

'A cylindrical offtake conduit 24 opens centrally through the front header plate 2 and communicates with the interior of the drum, this conduit extending horizontally outwardly through a central clearance opening in the closure member 13. Similarly, an intake conduit 25 opens centrally through the intermediate header plate 3 and projects horizontally through the rear header plate 4 and rearwardly beyond the discharge casing 23.

The weight of the cooler in major part is supported for rotation upon rollers 26 mounted upon concrete blocks 21, and these rollers engage riding rings 28 encircling and secured to the circumference of the drum 5 distantly spaced apart, as shown in Fig. 1. A pinion 29, driven by a motor M through a speed reducer 30, meshes with a ring gear 3| girdling and fastened to the drum. Thus, when the motor is operated, the drum is rotated by the pinion 29 on the rollers 25.

A centrifugal blower 3 I a. mounted upon a foundation block 32 beyond the rear end of the cooler is, driven by a motor M and the discharge port of this fan is arranged in line with the intake conduit 25, to which it is connected through the intermediary of a sleeve 33. Because the intake conduit rotates with the cooler while the discharge casing 20 and sleeve 33 are stationarily mounted, a slip connection to seal the clearances between the movable and non-movable parts is provided. As best illustrated in Fig. 6, the opening in the casing through which the intake conduit extends and the opposed end of sleeve 33 are formed with radial flanges 34 and 35, respectively. Surrounding and arranged to rotate with the conduit are rings 36 and 31, these rings being biased into bearing contact with the adjacent flanges 34 and 35 respectively, by means of a series of coil springs 38 interposed between the rings. The flanges 34 and 35 and rings 36 and 3'! are faced with suitable resistant material, indicated at 39 to take the wear between these parts.

At the forward end of the cooler, the end of oiftake conduit 24 lying exteriorly of the closure member I3 is joined by a slip connection to a duct 40 which delivers the heated air leaving the cooler either to the kiln burner (not shown) to serve as the primary air of combustion or directly into the kiln to serve as the secondary air of combustion, or the duct may convey the heated air to any other part of the plant where it may be advantageously utilized. This slip connection comprises a sleeve 4| having an outwardly directed flange 42 and an extension telescoping over the forwardly projecting end of the offtake conduit 24. A pair of rings 42 and 43 encircling the offtake conduit and biased by coil springs 44 into engagement respectively with the flange 42 and closure member l3 act as a seal for the clearances between the relatively movable parts, essentially in the same manner as the slip connection at the opposite end of the cooler, illustrated in Fig- 6.

In the light of the foregoing description, the operation of the cooler will be understood. By means of the motor M, the cooler is rotated about a generally horizontal axis but being inclined sufficiently to insure the travel of the material to be cooled through the tubes under the combined action of gravity and the agitation resulting from rotation of the cooler. Hot lime, cement clinker or other material issuing from the rotary kiln l l drops down into the hopper 9 from which it passes by way of spout 8 into the compartment defined by casting I at the forward end of the cooler. The material is there elevated by the wings 1a during rotation of the cooler and directed into the forward ends of muflle tubes I.

In passing through the portion of the tubes enclosed within the drum 5 the material is indirectly cooled by the current of air discharged by blower 3| into the drum from intake conduit 25 and which, by reason of the baffles 6 and 6a, is directed to flow back-and-forth across the tubes in an undulating path, resulting in the abstraction of heat from the material through the thin metal walls of the tubes. The air, which has been appreciably heated by its passage through the cooler, is led off through the offtake conduit 24 and delivered, for example, to the burner for injecting the fuel--pulverized coal or fuel oil-into the kiln. The material having undergone a lowering of its temperature while passing through the drum I, continues its travel through the tubes, which latter for the portion of their length between the intermediate header plate 3 and the rear header plate 4 are open to areas e9 or oxygen in the airat high temperatures, for

the reason that the material is maintainedexcluded from the atmosphere duringit passage through the cooler.

Because of the location of the intake andofftake conduits in the headers forming the end walls of the drum and the location of the blower beyond. the end of the cooler, air under pressure and at high velocity may be forced through the drum while avoiding infiltration of outside air into the drum. Serving also to increase the coolingeffect is the'exposure of the intake conduit to the water spray which chillsthe incoming air prior to its introduction into the drum, this cool,-

ing efiect also being accelerated by the rapid evaporation resulting from the free access of air to the water-sprayed tubes.

It will be apparentthat the invention provides a cooler in which an efficient cooling of the material is accomplished in two successive: stages, first by subjecting the tubes to a rapidly flowing stream of outside air, and the subsequent rapid quenching of the tubes under a water spray, as

sisted by evaporation of moisture from the tubes.

By virtue of this construction a certain amount of the heat is reeupera'ted from the cooler for use in other parts of the apparatus or elsewhere in the plant, and becauseoi therapid cooling action of the water, the distance of" travel of the mate rial within the tubes in order to lower its temperature to a point where it may be readily handied, is materially shortened;

Instead of locating the air-cooled section at the forward end of the cooler, it may if desired be located at the rear end. Such construction might be advantageous when a large supply of warm water is required, or when rapid cooling at the feed end is desirable on account of excessively high temperature of the material being cooled. Such a modification is schematically shown in Fig. '7, in which parts corresponding to those of the cooler of Figs. 1-6 are designated by like reference numerals.

It is to be understood that the invention may be embodied in forms other than that described above, which is to be regarded as exemplary rather than restrictive of the invention, without length and said tube being uncovered for another portion of their length, conduits for introducing air into and removing it from the housing through opposite ends of the housing one of said conduits extending interiorly of the path of rotation of said tubes, means for moving air ill through said-conduits and housing under pres;- surc; and means for exteriorly water cooling the tubes at their exposed portion.

2. A rotary tube cooler comprising front and rear header plates, a series of laterally spaced apart muffle tubes extending between and opening through said header plates, means for rotating said header plates and tubes about a generally horizontal axis, a housing having closed ends surrounding said tubes fora portion of their length and said tubes being uncovered for another portion of their length, conduits forin-troducing a-ir into .and removing it from the housing through opposite ends of the housing one of said conduits extending-interiorlyof the pathof rotation of said tubes, means for moving air throughsaid conduits and housing under pressure, a compartment at the forward end of the cooler for receivingmaterial to be cooled, a spout for delivering material into said chamber, a casing defining adischarge compartment at the rear end of the cooler for receivingthe cooled material issuing from the tubes, said compartments beingclosed' to the'atmosphere, andmeans for exteriorly water-cooling the tubes at their uncovered portion.

3. A rotary tube cooler comprising'front, intermediate and rear header plates, a series or laterally spaced apart mufile tubes extending between and opening through sad header plates, a drum surrounding said tubes andextending between the front and intermediateheader plates, means for unitarily rotating said tubes, header plates and drum about a generally horizontal axis, said tubes being uncovered between the intermediate and rear header plates, means for passing material through said tubes, conduitsopening through the front and intermediate header plates for passing a stream of air through the drum, one of said conduits extending interiorly of the path of rotation of said tubes, means for moving air through said conduits anddrum under pressure, and means for directing water upon the tubes extending between the intermediate and rear headerplates. v

4. A rotary tube cooler comprising front, intermediate and rear header plates, a series of laterally spaced apart muiile tubes extending between and opening through said header plates, a drum surrounding said tubes and extending between the front and intermediate header plates,means for unitarily rotating said tubes, header plates and drum about a generally horizontal axis, said tubes being uncovered between the intermediate and rear header plates, means for passing material through said tubes, conduits opening through the front and intermediate header plates for passing a stream of air through the drum, and means for directing water upon the tubes extending between the intermediate and rear header plates, said conduit opening through the intermediate header plate extending axially of the cooler and opening through the rear header plate.

5. A rotary tube cooler comprising front, intermediate and rear header plates, a series of laterally spaced apart mufile tubes extending between and opening through said header plates, a drum surrounding said tubes and extending between the front and intermediate header plates, means for unitarily rotating said tubes, header plates and drum about a generally horizontal axis, said tubes being uncovered between the intermediate and rear header plates, means for passing material through said tube, conduits openin through the front and intermediate header plates for passing a stream of air through the drum, one of said conduits extending interiorly of the path of rotation of said tubes, means for moving air through said conduits and drum under pressure, and means for directing water upon the tubes extending between the intermediate and rear header plates, said drum being interiorly provided with baflies for deflecting the air stream back-and-forth across the tubes.

6. A rotary tube cooler comprising front, intermediate and rear header plates, a series of laterally spaced apart mufile tubes extending between and opening through said header plates, a drum surrounding said tubes and extending between the front and intermediate header plates, means supporting said drum-for rotation about a generally horizontal axis, means for unitarily rotating said drum, tubes and header plates, said tubes being uncovered between the intermediate and rear header plates, means for passing material through said tubes, an intake conduit opening centrally through the intermediate header plate extending interiorly of the path of rotation of said tubes, an ofitake conduit opening centrally through the front header plate, a blower connected with the intake conduit for forcing air into the drum, baflies located within the drum for directing the air back-and-forth across the tubes, and a spray for directing water upon the tubes extending between the intermediate and rear header plates.

7. A rotary tube cooler comprising front, intermediate and rear header plates, a series of laterally spaced apart muflle tubes extending between and opening through said header plates, a drum surrounding said tubes and extending between the front and intermediate header plates, means supporting said drum for rotation about a generally horizontal axis, means for unitarily rotating said drum, tubes and header plates, said tubes being uncovered between the intermediate r and rear header plates, means for passing material through said tubes, an intake conduit opening centrally through the intermediate header plate, said intake conduit extending axially of the cooler beyond the rear header plate, and ofltake conduit opening centrally through the front header plate and extending axially and forwardly of the cooler, a blower connected with the intake conduit for forcing air into the drum, baflies located within the drum for directing the air backand-forth across the tubes and a spray for directing water upon the tubes and the intake conduit extending between the intermediate and rear header plates.

8. A rotary tube cooler comprising front, intermediate and rear header plates, a series of circularly-arranged, laterally spaced apart muffle tubes of relatively thin, heat-conductive metal extending between and opening through said header plates, a drum surrounding said tubes and extending between the front and intermediate header plates, rollers supporting said drum for rotation about a generally horizontal axis, means for unitarily rotating said drum, tubes and header plates, said tubes being uncovered and exposed to the atmosphere between the intermediate and rear header plates, an intake conduit opening centrally through the intermediate header plate and extending axially of the cooler through the rear header plate, an ofltake conduit opening centrally through the front header plate, a blower connected with the intake conduit for forcing air into the drum, a compartment at the forward end of the drum for receiving material to be cooled, a spout for delivering material into said chamber, a casing at the rear end of the cooler defining a compartment for receiving the cooled material issuing from the tubes, said compartments closing the ends of the cooler against the atmosphere, and a spray for directing water upon the tubes and intake conduit extending between the intermediate and rear header plates. RICHARD D. CHEESMAN.

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