US2090523A

US2090523A - Drying and heating apparatus

Info

Publication number: US2090523A
Application number: US80347A
Authority: US
Inventors: Whipperman Frank
Original assignee: Individual
Current assignee: Individual
Priority date: 1934-08-23
Filing date: 1936-05-18
Publication date: 1937-08-17
Anticipated expiration: 1954-08-17

Description

Aug. 17, 1937. wHlPPERMAN 2,090,523

DRYING AND HEATING APPARATUS Original Filed Aug. 25, 1934 INVENTOR FRANK. WHIPPERMAN.

BY a

ATTORNEY Patented Aug. 17, 1937 UNITED STATES PATENT OFFICE Original application August 23, 1934, Serial No. 741,073. Divided and this application May 18,

1936, Serial No. 80,347

2 Claims.

This invention has to do with the art of drying and heating apparatus in general and particularly with apparatus for drying and heating granular material such as carbonaceous fuels 5 and the like in the method. of making fuel-blocks described in my application for patent therefor of August 23, 1934, Serial Number 741,073, of which this application is a division, the agitating mixer herein described being fully described 7 10 in my application therefor Serial No. 12,710 filed March 23, 1935, now matured into Patent #2,045,1'70, issued June 23, 1936, said application having also been divided out of the original application filed August 23, 1934, above referred to.

Briefly, the above mentioned method of making fuel-blocks consists in the drying and heating of granular fuel material such as coal and coke screenings and fines and the like by pocketing or smothering therein hot combustion prodr ucts from a suitable source of supply, mixing molten asphaltic binder with the dried and heated fuel material, and then blocking the hot mixed material.

To satisfactorily prepare the granular fuel material for blocking or briquetting substantially all the moisture contained therein mustbe driven therefrom andthe material heated to a suitable temperature for mixing with the molten binder.

In preparing the granular fuel material for blocking in the making of fuel-blocks, great difficulty has been experienced in drying and heating said material, particularly when the moisture content thereof is high as in certain lignites and petroleum coke wherein often as much as 3 forty or fifty per cent of moisture may be present.

Economical and eflicient carrying out of any method of making fuel-blocks requires the rapid treatment of the granular fuel material to a high temperature to quickly dry and. heat same to reduce to a minimum the consumption of fuel required for said drying and heating of said material.

It is therefore an object of my invention to provide apparatus of this character for thoroughly drying the fuel particles, heating the same sufficiently to insure the uniform coating of the particles with molten binder, and eliminating from the product water and certain volatiles and deleterious ingredients such as sulphur, gas et 50 cetera, and utilizing the heating values of such eliminated constituents to furnish a portion'of the heat required for the preparing operation and thereby effecting the drying and heating of the material with a minimum expenditure offuel.

A further object of my invention istoprovide such an apparatus wherein the heat and flames from a furnace or other suitable source of supply will be properly directed to provide a maximum of heat in the fuel-material.

A further object is to provide apparatus of this character that is relatively inexpensive to manufacture and install and that is simple in construction and operation.

Other objects of my invention will appear in the following detailed description taken in, connection with the accompanying drawing where- The figure is a vertical section through the furnace and operatively associated agitating mixer.

Referring more particularly to the drawing which shows the preferred embodiment of my invention, the drying, heating and expulsion of volatile and vaporous matter from the granular fuel material is effected in an agitating mixer having a cylindrical body Ill closed at the ends by end members or walls I I. The body I!) is provided with a central opening I2 in the top thereof through which granular fuel-material to be heated and dried is admittedfrom a supply hopper I3. Doors M are provided at the lower end of the hopper I3 and said doors may be opened to permit fuel-materialto pass from the hopper into the cylindrical body. The doors M are normally closed to retain the next batch of fuelm-aterial in said hopper until the previous batch has been treated in the mixer and discharged therefrom and the mixer is ready to receive the succeeding batch of material. An outlet I5 is provided in the lower body wall through which treated fuel material is discharged into a reoeiving hopper I6 of a blocking machine, not shown, upon the opening of a door H which normally closes said outlet I5. Agitation of materials in the cylindrical body is effected by a plurality of part-helical blades I8 mounted on supporting arms I9 secured to a square shaft 20 rotatably mounted centrally of the cylindrical body. Each blade is provided with a. flangeZI extending outwardly and slightly downwardly from the lower edge thereof.

Heat for drying and heating the batch of material in the mixer is supplied from a furnace 22 preferably positioned beneath the mixerthough it may be placed at the rear thereof or in any U other suitable position. The mixer body is provided with an inlet 23 adapted to receive hot combustion products downwardly into said body from conduit 24 of the furnace, said conduit being an integral part of the furnace andhaving its outlet 25, of reduced dimensions, in register with the inlet 23 of the mixer. The conduit 24 has a fire-brick arch 26 at the top thereof which directs the heat, gases and flames from the combustion chamber 21 of the furnace downwardly into the mixer. Said conduit is also provided with a wall or baffle 27, transversely pointed at the top 28, said pointed top extending into the archway 25, at the highest point thereof.

The upper point 28 of the baffle 21 is higher than the lower edge 29 of the arch so that heat, gases and flames of the furnace are directed downwardly and not directly across the top portion of the mixer and out the outlet 30 thereof.

The bottom or ash-pit doors of the furnace, not shown, are normally kept closed. A blower 3| delivers air into the ash-pit 32 through an opening 33 in the furnace wall, whereby forced draft may be applied to the furnace and the volume of air passing through said furnace effectively regulated.

In drying and heating granular fuel material in the mixer said material is thoroughly agitated, rolled and tumbled therein by the blades which carry the material upwardly in the body of the mixer and drop same down. as said blades approach the upper regions of the body. The heat and gases from the furnace are somewhat compressed as they pass through the reduced or constricted outlet 32 of the conduit and as they leave the conduit they expand in the mixer. The constriction of outlet 32 compresses the combustion products, increasing the temperature thereof and adding to the velocity. thereof into the mixer. Said combustion products are directed almost directly downwardly by the arch of the conduit, directly into the agitated mass of fuel-material in the lower portion of the mixer and the material dropped from the blades thereof cover and pocket or smother said combustion products. The blades then agitate the heat and gases and fuel material and thoroughly mix same together.

In this manner the material is dried and the Wet gases and vapors from the material escape from the mass of material and pass out the outlet 38. The blades are diametrically opposed to each other in the mixer. While the upper blade is dropping material to pocket or smother the hot combustion products and passing the inlet 23, the opposite blade is approaching said inlet.

During a brief interval, after one blade has passed the inlet 23 and the opposite blade has not reached the outlet 30, no barrier is presented to the heat and other combustion products entering the inlet and a portion thereof will pass from the inlet, into the mixer, and leave through the outlet without being mixed with the material in the machine. A draft is thereby created which clears the upper part of the mixer of all moist vapor and gases. The rising blade then passes the outlet 30 and drops material from the flange, stopping the direct passage of heat and gas from the inlet across the upper portion of the body and out through outlet 30. Due to the blades not extending the entire length of the body of the machine there is a slight draft about the inner ends of the blades at all times to aid in the expulsion from,

the machine of moist vapors and gases driven from the material being treated.

It is found inpractice that by supplying sufficient heat to the mixer by the burning of outside coal or other fuel to evaporate the moisture in the granular fuel-material in the machine and raising the temperature thereof by pocketing or smothering said heat,and flames, in the material the direct application to and generation of heat within the material itself.

Also, bythe described mode of operation, discharge of unburned volatiles and dust into the air is avoided, and there is no liability or danger of explosions by accidental ignition of dust, or unburned volatiles expelled from the granular fuel material by the heating thereof to the temperatures desirable for mixing with binder material and for the blocking of said material.

Ignition and burning of. the material itself is prevented by the constant tumbling and agitation thereof by the blades and the drying and heating is so controlled that the temperature of the material being treated may be raised in the mixer to any desired point at which said material is best suited for mixture with the binder and for blocking.

The drying and heating apparatus herein described may also be used to dry other granular material such as sand and minerals and it will dry and heat such materials much more eifec tively than can be effected with present apparatus.

My drying and heating apparatus isrelatively simple and inexpensive to manufacture and the cost of drying and heating granular material, particularly granular fuel material is very low as compared with present apparatus.

It is, of course, to be understood that the invention may be constructed in other manners and the parts associated in other relations, and therefore, I do not desire to be limited in any manner except as set forth in the claims hereunto appended.

Having thus described my invention what I claim is:

1. In drying and heating apparatus for gran ular material, the combination, an agitating mixer having a horizontal, substantially cylindrical body with an inlet for hot combustion products adjacent the top thereof and to one side of the Vertical center and an outlet for moist vapors, said inlet being adapted to admit thehot combustion products downwardly into said body, a plurality of blades extending longitudinally of the body and rotatable therein to'agitate and mix granular material therein, a furnace in close association with the mixer for supplying hot combustion products, including flames, to the mixer body, a conduit connecting the furnace with the mixer body, said conduit being short enough to permit flames from the furnace to enter themixer body and reach the lower portion of said body, and means for directing said hot combustion products, including flames, downwardly through the inlet.

2. In drying and heating apparatus for granular material, the combination, an agitating mixer having a drical body with an inlet for hot combustion products adjacent the top thereof and an outlet for vapors, said inlet being adapted to admit said hot combustion products downwardly into the horizontal, substantially cylin-- body of the mixer, a plurality of rotatably mounted longitudinally extending mixer blades adapted to agitate granular material in the mixer, a furnace in close association with the mixer, a conduit connecting the furnace and the mixer body, said conduit being short enough to permit flames to enter the body from the furnace and reach the lower portion of said body,

said conduit being arched adjacent the upper end to direct hot combustion products downwardly into the mixer body, and a transverse baffle inthe arch with the upper end of said baffle positioned above the outer edge of the arch opening to prevent said hot combustion products from passing laterally outwardly from the conduit.

FRANK WI-HPPERMAN.