US2452362A - Apparatus for treating flowable solids - Google Patents

Description

Get 26, 19. J. L. ERISMAN 2,452,352

nrrmw us FOR TREATING mom 811E soups Filed Dec. 19, 1944 5 Sheets-Sheet 1 J. L.. ERISMAN 2,452,362

Filed D90: 19-, 1944 J. a. ERISMAN urmrus FOR TREATING momma somns Filed 1m 19, 1944 5 s eets-sheet s J. L. ERISMAN APPARATUS FOR TREATING SOLIDS s Sheets-sheet 4 Filed D90. 19, 1944 i/wil Oct. 26, 1948.

Filed Dec. 19, 1944 J. L; ERISMAN 2,452,362

APPARATUS FOR TREATING FLOWABLE SOLIDS.

5 Shee ts-Sheet 5 Patented Oct. 26,1948

AYPARATUS FOR TRE SOLID QFFICE ASTING FLOWABLE John LErisn'nan, Oak Park,'lli., assignor to Link 1 Belt Company, a corporation oi Illinois Application December 19, 1944, Serial No. 568,859

, ii a This invention relates to new and useful improveinents in apparatus for treating flowablc solids, and deals more specifically with apparatus which will screen and cool such solids and effect separation and removal oi-dust, or'other fines.

Although this apparatus ls suitable for treating' many diiie'rent materials and for use as 'a primary cooler, if the temperature'reduction desired'isnot too-great, it specificallywllibe describedin connection with its use as a'screening and auxiliary cooling unit for foundry sand being reconditioned "or reclaimed.

The patent to Hartley and Whitehead, No. 2,326,218, issued August .10, 1943,"discloses'and claims a method of and apparatus for'reclaiming foundry sand, and particularly core sand, so that it will be suitable for re-use. This patented method and apparatus includes thesteps of heating the used core sand to'withln' a temperature range of from 500to1500 Fitc drive oil the burnt 'and spent binder ma'terials -andother foreign matter adhering 'to the sand grains; then passing the hotsandthrough arotary, in-

ternal louvre cooler of the type broadly covered by the patent to Bojner and Pehrson,-'- No. l,'?09, i56, issued April" 16, 1929;= and finally screening the sand vto remove all oversizematerial and delivering the reclaimed sand grains of proper size to a belt conveyor 'which'xcarries'it to storage or tozvthezproper location "in the foundry for immediate re-use. ii g The xrotary; louvre 1 cooler :employed: sin'i the above noted patentedimethodw'of courseycan be p, providedof a' proper size to efiectianyxztemperatur {reduction that is necessary to condition the '3 so. d fors'iafeahandlingxby a belt conveyo'nrorilor storegejor immediate rez-usex slit has-been; deter-- mined; fho wevencthat a= considerablew-ssaving in the. total cost ofztthisitypeJofzxsand reclaimingiinr stallation' canxbe" effected loycemploying a rotary,

louvreacooler of a size'Which is :capabl'e ofFreducing'. "the: temperature oizithe- :sa'nd: only to-:a: value whichclwill tpermitwit ito; i bezzhandled safelyf by; 5a

vibrating screen and zby efiecting: ,theilfinalxrtems peraturevreduction awhile 'screening, out thetoversize, material 1 and: i effecting athecr'removalzi of i.the dust resulting from the screening operation. "It? is ":the: :primary; :object of suns invention to .provide-;-:an in'expen'sivei? compacts-unit lLWhldh: sis

.capablesofsscreenixigizand :-:coo1ing:"flowableisolids .andvrremoving-x the; dust: hat: ,screenin'g-mperationi: t I

15 10 provide apparatusisof ti-tlie above-mentioned type iiivhichrr'employsi aa singlertorc'ed zflowf-iofi'aic "tit 'tion will be apparent during throughoutthe same,

4 i'liaims. (Ci. 22-89) for cooling the materialboth while it" is being screened and after it has passed through the screen; for assisting in" maintaining the material in a loose or unpacked condition whilein engagement with the screening-surface to facilitate separation of dust, and forearrylngofi the separ t dust. t f f I t. 1 Insand reclamationinstallations offthe'above noted type fithe temperature reducing capacity of a given size' of irotary, louvre cooler can-be increased by spraying water onto the sand passing 'therethrough. The sand'discharged frorna rotary cooler oi this type'carries withit some moisture when it is discharged. i a I A "further primary-'objectof the invention is to utilize the forced flow of cooling and dust iremoving-air to drive ofithis moisture from the sand 'while it-is'-'beingscreened and cooled. nther obiects and 'advantages of thevinven thec'oursefiof the following'description. r

In the accompanying 1:drawings nforming a part of this speclfication' -and in? which like numerals areLe'mpIOye'd to designate like parts rFigure-i-i is az'side elevationallvievv oi? C l'IGL' fiOW ablewsolids treatingl appa tusi'embodying this invention; 1 J-AFigura 21s aafront-elevational view oi the .apparatusdiscloseduin Figil; c a an: rig- 1 :Figure Janis ;an: enlarged iverticali sectional view taken on'linetof-Figimr Figure 4 is a vertical sectional view takemon 1ine. 'Of'mg.'73 2. (1, 5-; 1.: SI .i: t Figure :5 is .a :top' plan iewppartl brokenaway, of the;apparatusz'discloseciain:Figs;v 3 and-54', -11: 1:. Figure 6111s a, detail; :.:horizontal sectional view Figureufiwis": an elevati'ona view of th-ecfra'g; mentary portio :0 th pparatus'disclosedin Fig.=:6,-and.r -w-Figure:'=.8 1' is a stall. vertical section takeniornline; ofsliigiz 'qxIn: theztdra'wings, hereinsfor he purpose": illustration :is. showmithe.epreferrdienibodiment otthis: invention, :and firstieparticularly referring torEigswlii and 2;eth reference numeralulii designatesithe discharge end i'oita; rotaryplouvrekicooler of thezitypexdisclosd iin-i' theiiaforesa'id patent "to Bo'jner i'andzPehrsoniia Il'usaunit constitutes-t the primary cooler of the fiowable solids treating apparatusiawhenithis apparatus is employedizas apart oiiian installatiori sfor reconditioning :oit; retclaiming oundryt s'and'. 'Tlieiifsolid'sdischarged from itheiirotary icooler iii] are received hythe The discharge chute i2 is suitably connected I Figs. 1, 2 and 3 as being connected to the outlet to an extension ll that is illustrated in Figs. 3

and 5 as being connected to and extending into a stationary cover, or exhaust hood, l5. This exhaust cover or hood is properly shaped to provide an exhaust opening II for connection with an exhaust duct I! that is shown in Figs. 1 and 2 as extending to and communicating with the exhaust duct i3 of the primary cooler discharge hood ll.

Positioned beneath the exhaust cover or hood i5, and telescopically associated with the base flanges lid of the cover or hood I5, is a vibrating screen that is designated in its entirety by the reference character it. This vibrating screen may be of any desired conventional type but for the purpose of this disclosure it is illustrated as consisting of a screen box I! that is supported for vibratory movements by the leaf springs 20. A screen cloth, of appropriate mesh, 2! is properly positioned within the screen box it. A belt driven vibrator unit 22 is suitably attached to the screen box i9. Fig. 1 discloses a motor 23 for driving this vibrator unit.

Suitably attached to the screen box It, and forming therewith a composite vibrating structure, is a pan 2. This pan is of box-like construction for it includes suitable side and end walls.

Figs. 3 and 4 disclose the pan 24 as being provided with an inclined bottom wall structure 25. This bottom wall structure is intended to allow for the passage of air therethrough and to cause the solids to cascade thereover so as to be subjected to the air that passes through this wall structure. One construction that will accomplish these two functions is illustrated as consisting of a series of spaced, partially overlapping or stepped louvre plates 2!. It will be noted that this bottom wall structure bridges all of the interior of the pan with the exception of a portion that is left at the bottom of the inclined wall structure to provide a discharge opening 21'. It will be noted that this discharge opening underlies the discharge end portion of the screen cloth 2i.

Figs. 3 and 4 disclose in detail a stationary hopper 28 that is positioned beneath the pan 24. This hopper is formed with the side walls 29 and 30, see Fig. 4, the front wall 3i, the rear wall 32, and the inclined bottom wall 33, see Fig. 3. The open top of this hopper 28 corresponds in dimensions with the bottom of the pad 24 and a canvas, or other flexible material, seal 34 closes the space between the hopper and the pan to prevent the leakage of air and dust while allowing the pan to vibrate relative to the stationary hopper. This hopper is provided with a discharge opening 25 that communicates with a discharge chute 36. It will be noted by inspecting Fig. 3 that the discharge opening 35 of the hopper is vertically aligned with the discharge opening 21 formed in the bottom wall structure 25 of the pan II.

An opening 31 is formed in the front wall 3| of the hopper. The discharge end of the cold airduct 18 is suitably attached to the margins of this opening 31. This duct is illustrated in of the blower 89 that is driven by the motor "a.

This cold air duct 38 is illustrated in Figs. 3 and 6 to 8 inclusive as including an elbow portion 380. To cause the flow of air to be uniform throughout the cross section of this elbow, a series of parallel partition walls 38b are arranged within the bore of the elbow. These partition walls are shown in Fig. 6 as terminating at the discharge and of the elbow 38a, or at the entrance to the air inlet opening 31 of the hopper 28.

Figs. 3, 4 and 6 disclose a series of vanes 40 as being attached to the front wall 31 of the hopper in alignment with the air inlet opening 31 formed in this wall and with the discharge and of the cold air duct elbow 38a. It will be noted by inspecting Fig. 3 that the outer edges of these vanes 20 are stepped and that these vanes lie in the path that extends between the discharge opening 21 of the pan bottom wall structure 25 and the discharge opening 35 at the bottom of the hopper 28. g

The discharge chute 36 of the hopper 28 is intended to deliver the completely cooled solids to a conveyor which will carry the solids, such as reclaimed core sand, to a storage bin or to a proper place for immediate use.

Figs. 1 to 4 inclusive disclose the discharge chute 36 as delivering the solids to the upper, or active, run ll of a belt conveyor. This belt conveyor is illustrated in Figs. 2 and 4 as being trained over an end roll 2. Suitable idler roll assemblies, not shown, will be provided for properly supporting the runs of the belt conveyor during the remainder of their paths of travel. Figs. 3 and 4 disclose in detail a supporting plate 43 which underlies the top run ll of the belt conveyor where it receives the solids from the discharge chute 36 of the hopper 28.

It is deemed advisable to enclose the reclaimed sand, or other cooled solids, while they are being conveyed away by the upper run M of the belt conveyor. For this reason, a housing overlies the active run of the conveyor. This housing includes the cover'plate N and the side skirts 15. A canvas, or other flexible material, sealing strip 46 depends from the bottom edge of each of the side skirts l5 and the hopper discharge chute 36. Seal ofi' curtains ll depend from the cover plate 44 of the casing that overlies the active run ll of the conveyor belt. These curtains may be made of canvas. or other flexible material, and function to prevent loss of cold air down the path of the conveyor.

Figs. 1, 3 and 5 illustrate a refuse chute 48 as being connected to the exhaust cover or hood l5 in a proper position to receive the oversized material discharged as tailing from the vibrating screen. A back suction closure gate 49 is provided for the chute 48. This gate is kept closed by the air suction created in the chute 48 as a result of the flow of air upwardly through the vibrating screen and the exhaust cover or hood i5. Of course, this gate opens to allow for the discharge of the oversize material when it flows through the chute 48.

By inspecting Fig. 3, it will be seen that the solids are delivered by the feed chute extension ll onto the receiving end of the screen cloth 2i. These solids will move down the screen cloth while sand grains, or other solids of proper particle size, pass through the screen cloth and the oversize material moves on into the refuse chute 48. The solids that pass through the screen cloth fallonto -"the*louvr'e plates of thebot'toin wall structure ofthe pan i k-"The solids are caused to-cascade .over'th'e louvre plates-until they reach the discharge opening 21- when' they will be delivered to theihopper 2!. In falling through the hopper. the solids will encounter the vanes 40 and will cascade over the-outer edges of thesewanes until they reach thedischarge opening 35 of the hopper. After passing through this discharge opening, the solids will be delivered onto the upper; run of the belt conveyor by the hopper discharge chute 38.

' The forced supply of cold air is discharged into the interior of the hopper Ruby the duct 38; J In Jeavingthe discharge end of the ductelbow 88a,

the cooling air will pass betweenthe vanes lfland will be directed intothe stream of solids cascoding over these vanes. The ,coolingair,-therefore, will be placed in intimate contactwith the through this cascading layer of solids, the air flows upwardly countercurrent to the falling solids from the screen cloth it. The air, also, will flow through the layer of solids moving over the screen cloth, Therefore, further intimate contact between the cooling air and thesolids is provided in the pan is and at the surface of thescreen cloth. After passing through the solids on the screen cloth, the air moves upwardly into the cover or hood l5 and then into the exhaust duct ll.

It will be appreciated that dust, or fines, will be separated from the solids during the screening operation. The passage of the cooling air through the solids moving over the screen cloth will tend to maintain the solids in a loose, unpacked condition and will consequently assist in the operation of separating dust. This dust will be carried into the cover or hood l5, and the exhaust duct W, by the upward ilow of air from the screen cloth.

In some installations water is sprayed onto the solids passing through the rotary cooler it to assist in lowering the temperature of said solids. Such an operation may result in the discharge of moist solids from the hood ii. The flow of cooling air through the solids passing over the screen cloth will drive off this moisture.

It is to be understood that the form of this invention herewith shown and described is to be taken as a preferred example of the same, and that various changes in the shape, size, and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

Having thus described the invention, I claim:

1. Apparatus for cooling, screening and removing fines from iiowable solids, comprising the combination with a rotary primary cooler having a stationary hood provided with chute for discharging the partially cooled solids and a duct for exhausting the spent cooling air, of a vibrating screen receiving the solids from the discharge chute, a pan attached to the bottom of the screen to vibrate therewith, an inclined series of louvres bridging a portion of the interior of the pan and over which screened solids casthe interior of the pan and over which screened Whittle! i bet s-rich,ins-1 m oi "the series, a stationary hopper positioned below the receive the solids discharged from the lower end of-the series oi'louvres, said hopper having a dischargejopening underlying the unbridsed portion of the'pan, a blower having a discharge duct located at .oneside of andopening through the side V hopper sothat it will pass first through the stream or'solidsdischarb ing from the series of'louvres, then through the 'solidsfcascading over the 'louvres, "and finally through the solids moving over the'screen tc'effeet final cooling of saidsolids, a stationary cover 'overthe vibrating screen. to receive the air and suspended tines rising from the solids on the screen," and gap; exhaust duct connecting the cover to the exhaust duct of the primary cooler.

2. Apparatus, for cooling, screening and removing fines from flowable solids, comprising the combination with a rotary primary cooler having a stationary hood provided with a. chute for discharging the partially cooled solids and a duct for exhausting the spent cooling air, of a vibrating screen receiving the solids from the discharge chute. a stationary hopper having a bottom dis-v charge opening positioned below the vibrating screen, a pan interposed between the vibrating screen and the hopper and attached to the bottom of said screen to vibrate with the latter, an inclined series of louvres bridging a portion of solids cascade before being discharged from the lower end of the series, means for sealing between the vibrating pan per to prevent leakage of air, a blower having a discharge duct opening through the side of the hopper for introducing a forced draft of cooling air into the hopper, a series of vanes, having stepped outer edges, positioned in the hopper in alignment with the duct opening and projecting into the vertical path lying between the discharge opening of the hopper and the lower discharge end of the series of louvres, the cooling air being introduced 50 that it will pass first through the stream of solids discharging from the lower end of the series of louvres, then through the solids cascading over the. louvres, and finally through the solids moving over the screen to effect final cooling of said solids, and means overlying the vibrating screen to exhaust the air and suspended fines therefrom,

3. Apparatus for cooling and screening hot foundry sand, comprising a vibrating screen box having a screening surface receiving the hot sand, a pan attached to the bottom of the screen box and underlying the entire screening surface, an inclined series of overlapping, spaced louvres arranged to bridge all of the bottom of the pan with the exception of that portion which unerlies the discharge end portion of the screening surface, whereby sand passed through the screening surface will fall onto the louvres and cascade thereover before being discharged from the lower end of. the series, a stationary hopper beneath the pan and having a discharge opening underlying the unbridged portion of th pan botofthe hopperfadjaceiithits. -dischar g e openingj for delivering i a forced j "draft of cooling air" into the and the stationary hop-' amazes 1 from the discharge end of the series of louvres, then between the louvres and through the sand cascading thereover, and finally through the sand moving over the screening surface, and means overlying the screen box to exhaust the air and suspended fines from said box.

4. Apparatus for cooling and screening hot foundry sand, comprising a vibrating screen receiving the hot sand, a pan attached to the screen to vibrate therewith, an inclined, stepped wall structure positioned in the pan and having a discharge opening at its lower end, said wall structure having openings for the passage of cooling air, a stationary hopper underlying the pan and having a discharge opening vertically aligned with the discharge opening of the pan wall structure, a forced air duct opening through the side wall of the hopper that is adjacent the said vertically aligned discharge openings so as to discharge the flow of cooling air at right angles to the path lying between said openings, a series of vanes having stepped outer edges, positioned in the hopper in alignment with the air duct opening and projecting into the said path lying between the discharge openings, the cooling air entering the hopper being directed to how through the air openings in the pan wall structure and through the vibrating screen, and means overlying the vibrating screen to exhaust the air.

JOHN L. ERISMAN.

' REFERENCES CITED The following references are of record in the fiie of this patent:

UNITED STATES PATENTS Number Name Date 317,094 Constant May 5, 1885 375,782 Stone Jan. 3, 1888 987,460 Heldman Mar. 21, 1911 2,326,218 Hartley et al Aug. 10, 1943 2,320,755 Smith June 1, 1943 FOREIGN PATENTS Number Country '1 Date 298,396 Great Britain Oct. 11, 1928

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