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Publication numberUS2808213 A
Publication typeGrant
Publication dateOct 1, 1957
Filing dateJan 13, 1954
Priority dateJan 13, 1954
Publication numberUS 2808213 A, US 2808213A, US-A-2808213, US2808213 A, US2808213A
InventorsLaurance Morrison Robert
Original AssigneeWest Canadian Collieries Ltd
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Gas entrained lump-breaking and drying equipment
US 2808213 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

R. L. MORRISON 2,808,213

GAS ENTRAINED Lum-BREAKING AND DRYING EQUIPMENT Filed Jan. 13, 1954 INVENTOR.

Robe/'f L. Morrison BY @4% jfv@ ATTORNEY \m R Q I m |||V| \V Oct. l, 1957 United States Patent 2,808,213 Patented` Oct. 1, 1957 hce 2,808,213 oA'sfnNrnAnvnD nUMP-BREAKnsG' ANDV DRYING'EQUIP-MENT Robert Lanrance-VMorrison, Blairmore,Albert, Canada,

assignor to.. West Canadian. Collieries, Limited, Blairmore, Alberta, Canada, a corporation of Canada Application January 1s, 1954, serial No. 403,829:

e claims.. (c1. 2211-40) This invention relatestoapparatus-for the rapid and continu-ous drying of finely divided materials lby the direct heat exchange with hot'gases at high velocities. The apparatus relates more particularly to improvements in uidized or gas entrained drying equipment.

Apparatus for-drying finely divided' solids in a-liigh velocity stream of hot gases is generally known. Such apparatus consists ofar combustion furnace for generating hot gases, ai drying chamber for entraining finely divided `material inan uprising stre-am` of the hot gas, and a. separator forseparating dried material from the spent gases issuing out of the drying chamber. In such apparatus the -hot gases from` the combustion furnace are passed through a rather narrow passage or neck upwardly into a drying chamber. The wet, finely divided material is introduced into the drying gases inthe neck, so as t-o suspend the material in the rising hot gases. The neck expands and connects with the bodyvof the drying-chamber above the rpoint of solidsintroduction. The sus# pended solids are maintained in a iluid-ized or-gas entrained state in the enlarged portion ofethe dryingfchamber until the particlessbecome substantially dry, when they are substantiallylighter in weight, at which point the dried solid-material is carried upandaoutof the drying chamber. A separator then recovers the dried product from the spent gases.

4The presentinvention provides an improvement over the known driers of the prior art. In the driers as known, there is a grading or other pressure or Velocity equalization constriction means across the hot gas inlet into the drying chamber. These constrictionstend to .aid the entrainment ofthe solids in the gas. With certain operations, however, very wet coal is encountered,especially wherelow rank coal has been extensively washedto remove rock-and ash impurities. The coal discharged from such a washing operation is of the character of a sludge, which cannot be dewatered within practical limits by mechanical means. The 4sludge packs or'lurnpsv into large particles which .are not readily entrained and dried in the drying chamber, and drop through the entraining constrictions, out of the drying cham-ber. Feed devices have been suggested for -breaking up the lumps, however, these have not been practical. It is an .object of the .present invention to provide an improved device for the fluidized or gas entrained heat transfer or drying of finely divided wet solids.

llt is another object of the invention to provide a simple and eflicient feed mechanism for wet coals and the like for hot gas driers.

yIt is still another object of the present invention to provide an improved method of the entraining of finely divided wet solids in a stream of hot gases.

These and other objects of the invention Will be readily apparent by referring to the following description and appended drawings in which:

Fig. l is a sectional View of the device according to the invention, including a partial view of auxiliary equipment used with the device.

`In the-device selected for illustration, a combustion furnace 10, only jpartly shown in Fig. 1 as it does not form a part of the invention, provides a stream offhot gases for drying solid material. The hot gases sweep down they furnace 10 around a bend 1-1 into a neck12 of a drying chamber 17. Swirl .producing/vanes 14 at the lower end of an entraining portion 15, violently swirl the hot gases, and baffles 16 directly above the vanes tend topstraighten thewhirling-gases-into straight line flowup the drying neck 15. The swirl vanes and .baffles aid in providing' a uniform pressure or velocity gradient across the entraining neck 15, for more eicient material spread and,` therefore, more etiicient drying. Wet coal is fed' by the feed'means 28 into the entraining chamber 15. The wet solidvis dropped generally toward the swirl andbaiiie means, and is picked up in the hot gases in the swirl means and-isentrained in the gases rising up through the chamber 15;

A by-pass 18l passes around the swirl producing means 14-and the baiiies 16 and exhausts immediately adjacent the feedmeans .outlet 30 in'chamber 15. The inlet 20 to the by-pass V18 isared-Hto act as a scoop for the hot gases throughthe by-pass. The resistance to flow through the by-pass 131s :less than through the swirl producing means, and so apart of the gas will pass through the =bypass means. The bydpass is small enough,rhowever, that the majority ofthe gas .passes through the swirl vanes for entraining solids fed into the drier. rilhe 'outlet 22 of the ibyfpasslSis'ilattened 'to substantially increase the velocity/*ofthe by-passed gas issuing from the outlet 22.` Thefeed means 28' consists of a screw conveyor which has-an'outletl 30 `along the Wall of the drier. The wet material ybeing exhausted from the feed outlet 30 falls directly intothe jet stream issuing from outlet 22, and--is -picked up. inv the jet stream'and carried across the drying column :and -forceafbly thrown into `the wall ataibout point 24.- rIlhe lumps which hit the `wa'll are effectively broken up andas they fall` from their'conta-ct with the wallthey are -picked'inthe gas stream andare .entrained for drying.

Aspiral conveyor 32is provided directly beneathithc drying chambery inlet 15 to remove ash brought over by the hot ngases from the combustion furnace 10 :and any largelumps of the-material which may drop through the lswirl producing means 14.

In general, the `by-pass 18-provides a smooth, circular conduit for tpassing a portion of the hot combustion gases aroundthe swirl producing means into the entraining chamber at 15. Theiby-pass is attened and somewhat reducedY in area at the-outlet 22 soas'to form a gas jet stream of highv velocity directly nextto'the outlet 30 of the feed means 28. The flattened end ZZeXtends sub'- stantially across the diameterof the outlet 30,` soy that any coal dropping from the feed means will .be picked up in the jet stream and will be forced across the drying chamber onto the wall 24. This jet stream insures all material issuing from the feed means will ibe broken into small particles for entrainment in the rising stream of hot gases.

vOthers may readily adapt the invention to various conditions and various modes of operation without departing from the spirit and the scope of the invention. It will .be apparent to those skilled in the art that the invention rnay .be modified without departing from the inventive concept.

II claim:

1. In apparatus for drying subdivided materials in a gas entrained state, an upright drying column, means for introducing heated gases into the lower en-d of said column, means for introducing material in subdivided :condition into ysaid column above its ybottom adjacent the side wall thereof, la series of vanes in said column intermediate said means for introducing said gases and said material for entraining said material in said gas, and a llay-pass duct means interconnected with said column for conducting a portion of said heated gases around said vanes, said duct means having a iiared inlet forming a scoop interconnected with and adjacent the lower end of said column and a constricted outlet adjacent the material inlet to said column, said outlet being arranged to provide a high velocity stream of gas directed transversely across said column whereby material may be entrained in said gas stream therefrom and be forced against the opposite wall to break up lumps of particles to be suspended in said gases.

2. yIn apparatus for drying subdivided materials in a gas entrained state, an upright drying column, means for introducing heated gases into the lower end of said column, means for introducing material in subdivided condition into said column above its bottom adjacent the side wall thereof, swirl producing means in said column intermediate said means for introducing said gases and said material, and by-pass duct means interconnected with said column for conducting a portion of said heated gases around said swirl producing means, said duct means having a ared inlet form-ing a scoop interconnected with the lower end of said column and a restricted outlet interconnected with said Icolumn ibelow and adjacent the material inlet to said column, said outlet being arranged to provide a high velocity stream of gases directed transversely across said column whereby material may be ,forced against the opposite wall to break up lumps of particles to be suspended in said gases.

3. `In apparatus for drying subdivided materials in a lgas entrained state, an upright drying column, means for introducing heated gases into the lower end of said column, screw conveyor means for introducing material in subdivided condition into said column above its bottom :adjacent the side wall thereof, velocity equalizing means in said column intermediate said gas introducing means and said conveyor means for entraining material uniformly across said column, and a by-pass duct for conducting a portion of said heated gases around said velocity equalizing means, said duct having a ared inlet yforming a scoop communicating with the lower end of said .column and a restricted outlet communicating with said column adjacent the material inlet, said outlet being arranged to provide a high velocity stream of gases directed transversely across said column whereby material from said screw conveyor means may be entrained and forced against the opposite Wall to break up lumps of particles to be suspended in said gases.

4. lIn apparatus for drying subdivided materials in a gas entrained state, an upright drying column, means for introducing heated gases into the lower end of said column, means for introducing material in subdivided condition into said column above its bottom, swirl impartcentrifugal movement to a portion of the entering gas to entrain said solids, and lay-pass duct means interconnesting the lower end of said column with a point thereabove for conducting 4the remainder of the entering gas -around said swirl means, said duct means having an outlet communicating with said column below and in proximity to the material introduction means arranged to entrain material in a stream from said duct and direct it onto Ithe column wall for breaking up lumps of material for suspending the same in said gases.

5. In apparatus for drying subdivided materials in a gas entrained state, an upright drying column, means for Y introducing heated -gases into the lower end of said column, means for introducing material in subdivided condition into said column above its bottom, swirl imparting means and baile means in the column intermediate said means for introducing said gases and material to entrain solids uniormly across said chamber, and by-pass duct means interconnecting the lower end of said column with a point above said swirl imparting and baille means for conducting the remainder of the entering gas around said swirl means, said duct means having an outlet located below and in proximity to the material introduction means arranged for breaking up lumps of material and for suspending the same in said gases.

6. In apparatus for drying subdivided materials in a gas entrained state, an upright drying column, means for introducing heated gases into the lower end of said column, screw conveyor means for introducing material into subdivided condition into said column above its bottom, said conveyor means exhausting adjacent the wall of said column, swirl imparting means in the column intermediate said points of introduction constructed and arranged yto disperse the divided material across the column, and by-pass duct means interconnecting the lower end of said column and an upper portion thereof for conducting a portion of said heated gases extending around said swirl means, the outlet of said by-pass duct means being A restricted for providing a high velocity stream of gas ing means in the column intermediate said means for Iintroducing gases and material and arranged to impart below said conveyor whereby material from the conveyor means is carried across the chamber and impacted into the opposite wall to break up lumps of material to be suspended.

References Cited in the tile of this patent UNITED STATES PATENTS 301,513 Newton July 8, 1884 2,021,171 Buck Nov. 19, 1935 2,272,564 Kuever Feb. l0, 1942 2,339,932 Kuhl Ian. 25, 1944 2,587,020 Wicker et al Feb. 26, 1952 2,607,537l Shaw Aug. 19, 1952 FOREIGN PATENTS 488,714 Germany Jan. 7, 1930

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US301513 *Dec 31, 1883Jul 8, 1884 Process of and device for ventilating and trimming grain
US2021171 *Nov 12, 1930Nov 19, 1935Charles M BuckPulverized fuel feeder
US2272564 *Jan 28, 1941Feb 10, 1942Blaine Rhoades FDry cement conveyer
US2339932 *Apr 10, 1941Jan 25, 1944Standard Oil Dev CoChemical process
US2587020 *Sep 10, 1948Feb 26, 1952American Viscose CorpAlkali cellulose temperature control
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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4496444 *Jan 5, 1981Jan 29, 1985Caunned AktiengesellschaftMethod of corrosion protection
US5946818 *Nov 25, 1994Sep 7, 1999Alcan International LimitedIn a liquid
US8245963 *Nov 20, 2007Aug 21, 2012Fives Fcb Societe AnonymeGrain size selection and/or matter drying apparatus
US20100133369 *Nov 20, 2007Jun 3, 2010Fives Fcb, Societe AnonymeGrain size selection and/or matter drying apparatus
DE1604993B *Apr 23, 1964Oct 1, 1970Mizusawa Industrial ChemMehrstufige Stromtrocknungsanlage zum Trocknen feuchten Granulats
DE2939029A1 *Sep 27, 1979Apr 16, 1981Bergwerksverband GmbhEinspeisevorrichtung fuer feinkoerniges schuettgut an einem flugstromrohr
EP0655597A1 *Nov 30, 1993May 31, 1995Alcan International LimitedProcess and apparatus for drying liquid-borne solid material
WO1995015470A1 *Nov 25, 1994Jun 8, 1995Alcan Int LtdProcess and apparatus for drying liquid-borne solid material
Classifications
U.S. Classification241/40
International ClassificationF26B17/10, F26B17/00
Cooperative ClassificationF26B17/103
European ClassificationF26B17/10B3