US1590798A - Drier - Google Patents

Description

June 29 1926.

w. M. BARKER DRIER Filed July 51, 1924 gwuenkw 11 M 320% Patented June 29, 1926.

UNITE STATES "aren't rein.

DRIER.

Application filed July 31,

The invention relates to drying apparatus for ren'ioring excess moisture from coal and other materials by means of heated gases; and the obiect of the improvement is to cause the wet material to flow continuously, in a uniform attenuated stream, through a current of the drying gas.

In drying apparatus of this kind it is difficult to bring every particle of coal into direct contact with drying gases; and for the purpose of bringingvevery particle of material several times into direct contact with a current of hot gas, the present invention involves the use of a series of superposed conical funnel chutes, a series of rotating disks therein for distributing the mate rial centrifugally from the periphery of the disks to annular walls at the upper ends of the chutes, so that the material is spread out and caused to fall through a current of drying gas circulated through and around the funnel chutes.

The improved apparatus is well adapted for drying lump or slack coal, as a preliminary step for a grinding or pulverizing operation, and the invention is illustrated and described with reference to such a use, without intending to limit it thereto; and in the accompanying drawings, forming part hereof, the figure is an axial elevation section of a centrifugal drier embodying the invention.

Upon a cylindrical case 1 is mounted a feed hopper 2 for feeding wet coal into the top of the case and a centrifugal fan 3 for exhausting drying gases. therefrom, there being a drying gas inlet 4: at or near the bottom of the case.

To the top wall 1 of the case is secured a depending annular wall 5, below which is secured a funnel hopper 6; and below the same, in the middle portion of the case, is secured a second depending annular wall 5? below which is secured a second funnel hop? per 6 1 The upper end 6 of the upper funnel chute is preferably secured directly to the wall of the casing. so as to leave an annular opening 7 between the top of the funnel and the bottom of the annular wall 5, leading into the annular chamber 8 between the depending wall 5 and the wall of the case 1, and the upper end 6" the lower funnel hop per is preferably secured directly to the bot-- toin of the 10 er aniiula' wall h fl whih in. nds me a ho iz nta 1. ti

tn the 1924. Serial No. 729,301.

In the bottom wall 1 of the case is mounted a discharge hopper 11, the upper funnel 11 of which surrounds the lower end of the funnel hopper 6 with an intervening annular opening 12; and the lower outlet end 11 of the discharge hopper is provided with a pendent gate 13, which is preferably counterbalanced by a weight 14 for normally holding it closed.

A vertical shaft 15 in the axis of the case is mounted'in bearings 16 and 17 at the top and bottom thereof, and upon this shaft, within each annular depending wall 5 and 5 is secured a horizontal disk table 18 or 18 having a peripheral diameter considerably less than the diameter of the wall, so as to leave an annular interval a substantial width between the periphery of the disk and the adjacent annular wall. p

The shaft 15 may be operated by a worm gearing 19 through a speed reducer 20 and chain gearing 21 by a motor 22, and the cen trifugal fan 3 may be operated through the chain gearing 21; and these parts may be arranged for turning the axial shaft some 59 R. P. M. for distributing the coal. and the centrifugal fan some 84-6 R. P. lvl. for ex" hausting some 3290 cubic feet of air per minute from an appartus having a case some six feet in diameter, for drying some ten tons of coal per hour from an eight per cent moisture to about a two per cent moisture.

The feed hopper 2 is provided with a feed gate 2for controlling the admission of wet coal into the apparatus, and the same is located so as to deliver wet coal upon the upper rotating disk 18. V In the operation of the machine, the rotation of the upper disk 18 spreads the wet coal and distributes the same by centrifugal force directly outward against the adjacent annular depending wall 5, whence it falls directly downward in a thin cylindric stream upon the conically converging wall of the upper funnel 6, by whichit is discharged on to the lower rotating disk 18 The rotation of th logii ei disk again dis-- tributes thy seal s any and throws in as Cir mushroom stream against the adjacent annular depending wall whence It drops downward 111 a thin cylindrie stream onto and along the coniea-lly converging wall of the lower hopper 6, whence it 1s delivered in a thin cylindric stream into the discharge hopper l1, and when a sufiicient'amount of coal is accumulated ther in to overbalance the outlet gate 2 the coal flows outward through the outlet.

The gas inlet 4 is connected with any suitable source of supply, which may be hot flue gas from a boiler or other furnace, and the operation of the exhaust fan 3e1rculates. the

same through the apparatus as indicated by arrows in the drawing, somewhat as fol lows: A portion of the hot gas flows througl'a the annular openings 12 between the bottom flowing outward from the rotary disk and thence converging into the rower end of the inlet opening 4; into another portion which flows, upward around the wallet the tunnel hopper and into and around the wall of the upper hopper; whence this portion of the hotgases flows inward and joins the other portion which flows upward through thelower hopper into the lower end of the upper hopper; whence the recombined hot gases flow upward and outward along the stream of coal flowing downward upon the bottom of the hopper and the attent-uated cylindric stream of coal falling down from the upper annular depending wall; and thence upward into and around the annular channel 8 around the same to the inlet 24; 0t the ez haustfan 3.

During the progress ofthe hot gases,

and out of the upper funnel, as it is thrown.

outward in a mushroom stream from the pe,

riphery of the lower rotary disk, and as it drops downward 1n a cylindric stream from the lower funnel. Furthermore the How of hot gases against the outside of the tunnel walls, and through the ports 9 or the hori- Zontal ring partition 9 heats both sides of the funnelwalls so that they in turn heat and dry the coal" sliding downward along the inside thereof.

By these means all the particles or the fed-in raw coal which may adhere or stick to each other are broken apart by the impinging centrifugal action or the mushroom streaans against the annular walls, there is no place in the apparatus where theseparated particle can accumulate or lodge in any considerable mass or quantity; so that every particle of the coal is brought into direct contact with the ascending hot gases, several times during its tortuous passage in attenuated streams; through the apparatus; and very little power is required to rotate the disks for spreading the coal and operating the fan; for circulating the hot ase T claim:

1. Material drying apparatus including a rotating disk, an annular wall spaced from the periphery of the disk, a funnel spaced from the annular wall, and means moving drying gas through the annular interval between the funnel andithe annular wall.

2. Material drying apparatus including anannular wall, a: funnel for converging a funnel and through; the annular interval between the funnel and the annular wall.

3. Material drying apparatus including a series. 0t rotating disks, one above the other,

funnels for receiving material distributed centrifugally by the d sks, an external annular wall spaced from the tunnels andthe disks, and means moving drying air around the inside and outside of the tunnels and through the intervals between the tunnels and the disks.

1 4. Material drying apparatus including a funnel, an external annular wall around the funnel, a ring partition, between the funnel and the external annular wall, and valve apertures 1n the rlng. I

In testimony that I claim the abore I have hereunto subscribed my name.

WILLIAM M. BARKER.

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