US2728454A

US2728454A - Portable apparatus for reclaiming metal scrap

Info

Publication number: US2728454A
Authority: US
Inventors: Eric H Heckett
Original assignee: HECKETT ENGINEERING Inc
Current assignee: HECKETT ENGINEERING Inc
Priority date: 1952-07-22
Filing date: 1952-07-22
Publication date: 1955-12-27
Anticipated expiration: 1972-12-27
Also published as: GB737756A

Description

Dec. 27, 1955 E. H. HECKETT PORTABLE APPARATUS FOR RECLAIMING METAL SCRAP 2 Sheets-Sheet 1 Filed July 22, 1952 MT m EF- O Dec. 27, 1955 E. H. HECKETT 2,

PORTABLE APPARATUS FOR RECLAIMING METAL SCRAP Filed July 22, 1952 2 Sheets-Sheet 2 FEZ &'\L g m "N E N I cu N INVENTOR 3' ERIC H. HECKETT ATTORNEY Unite States PORTABLE APPARATUS FGR RECLAIMING METAL SCRAP Eric H. Heckett, Valencia, Pa., assignor to Heckett Engineering, Inc., Butler, Pa., a corporation of Ohio This invention relates to combined portable apparatus for separating, cleaning, and classifying bulk waste materials as derived from steel-making operations for the purpose of recovering therefrom bulk materials having an acceptable purity of metallic content for reuse in iron and steel furnaces. Such initial bulk materials, particularly as derived from the open hearth departments of steel mills and in the form of sweepings, general refuse, and granulous slag, are normally rich enough in metallic values to economically warrant the processing thereof for the purpose indicated, and methods and plants for carrying out this processing, both on existing slag and refuse dumps and in connection with current steel-making operations, have been devised and are in rather widespread use throughout the steel making industry. It is the primary object of the present invention to provide an improved portable piece of equipment whereby the processing operations indicated and particularly the conversion of the initial bulk materials into acceptable reusable form may be carried out with increased efficiency and economy, it being widely recognized that the utility of the general processing mentioned is closely allied to and dependent on the cost of handling, separating, cleaning and classifying the initial bulk materials.

In furtherance of the above general object the present invention provides a unitary, compact, and portable piece of equipment which while being capable of being moved and serviced by other essential power equipment employed in the scrap recovery operations is operative to automatically process large tonnages of initial bulk materials fed to it to simultaneously separate the initial bulk materials into two component parts one of which has acceptable metallic purity, clean the particles of such acceptable component and classify the cleaned particles according to size whereby one final component is good material for charging in a blast furnace, for example, while the other final component is valuable metal bearing scrap material for reuse in an open hearth furnace, for example. More specifically the invention provides improved apparatus of the character indicated which is extremely rugged and durable and in which the improved ability to continuously processed large tonnages of material results from an improved mechanical arrangement of the cleaning and classifying structure of the assembly in relation to the material handling and separating structure of the assembly.

A further object of the invention is the provision in portable apparatus of the kind described of an improved mechanical structure for cleaning and classifying the materials being handled and of an improved method for mounting and driving such cleaning and classifying structures. Another object of the invention is the provision in providing apparatus for the purpose indicated of improved mechanical features for guiding the materials being processed through the apparatus involved and to separate discharge points whereby the assembled apparatus may be adjusted for continuous and substantially unattended operatet ation with maximum utilization of the facilities included and with the substantial elimination of any tendency of the assembled apparatus to clog.

The above and other objects and advantages of the invention Will become apparent upon consideration of the detailed specification and the accompanying drawing wherein there is disclosed a preferred embodiment of the invention.

In the drawing:

Figure 1 is a partial side elevation of portable assembled apparatus constructed in accordance with the teachings of the present invention; and

Figures 2 and 3 are end elevation and plan views, respectively of the apparatus of Figure 1.

The assembled apparatus of the invention is carried on a heavy elongated structural-steel frame 10 which at one end is supported on a pair of longitudinally extending but transversely spaced crawler-type of supports 11 and at its other end on a fifth wheel assembly 12. Wheel assembly 12 is, in turn, supported on a tongued truck 13 which also has a pair of transversely spaced crawler-type of supports 14. To lower the center of gravity of the assembly and thereby reduce the overall height of the same to facilitate loading, etc. the frame 10 is offset vertically as shown in Figure 1 whereby the bulk of the apparatus is positioned quite close to the ground or other supporting surface while the truck 13 is free to swivel in moving from one location to another. in normal usage the apparatus remains supported on the crawlers 11 and 14 on a slag dump or other fill and is moved about as required at the scene of operations by a large crawler or caterpillar-type of tractor as used for bulldozing work, for example, in

reforming the dump from the waste materials which are rejected from the apparatus of the invention in the manner to be hereinafter more fully described.

Rigidly mounted on the frame 10 in upstanding relation is a structural steel framework which supports, among other equipage, a magnetic separating roll 15 which is arranged to be driven at variable speed by a drive motor 16. The magnetic separating roll 15 is of more or less conventional construction and as such has, in addition to the provision of variable speed drive, means, not shown, for varying the intensity of the magnetic field applied to the materials passing over it whereby the intensity or degree of separation may be accurately controlled. The bulk materials to be separated are supplied to the roll 15 by a shaker-type of conveyor 17 which is arranged to be oscillated by a magnetic type of shaker 18 which, as shown, is rigidly connected to the end of conveyor 17 opposite the discharge end thereof over the roll 15.

Supported on the said structural steel framework above the swivel truck 13 and inclined downwardly toward the adjacent end of the assembled apparatus is a heavy steel grid 19, comprised of a plurality of longitudinally disposed bars 22 and transversely disposed bars 22'; onto which the bulk materials to be fed to the apparatus of the invention are deposited by such power equipment as clam-shell buckets, for example. Inclined front and rear hopper aprons 20 and 21, respectively, are provided to deflect material toward the grid 19 and to cause the larger sized pieces which are rejected by the grid to tumble free and clear of the apparatus. It should be understood that in normal practice the greater portion of the material fed to the apparatus of the invention is granulous open hearth slag and pulverulent sweepings and other debris and as such will readily pass down through the mesh of the grid. However, the pieces of the initial bulk materials which are too large to be handled by the apparatus will be rejected by the grid and will tumble down off the apron 20 onto a pile, not shown, in which they may be removed in part by a magnetic crane and in part by the bulldozer,

for example. The-materials which pass through the grid are collected in a hopper 23 the bottom wall of which is the belt 24 of an inclined belt-type of conveyor and, as shown in Figure 1, the upper end of such belt is entrained over a pulley 25 which is positioned above-the charging end of the conveyor 17. The relative arrangement of the hopper 23 and the inclined belt conveyor is such that the rate of feed of the conveyor'is properly limited to the capacity of a separating roll 15 and the other subsequent components of the assembly,the hopper 23 serving as a-storage bin which may be drawn on intermediate the depositing of the materials on the grid. The conveyor belt 2 5 is arranged to be driven by the roll ZS-Which, in turn, is driven by a motor 26 throughaspeed reducer 27 and a chain or belt 28.

Centrally disposed and extending upwardly and-outward-1y of the end of the assembled apparatus opposite the grid 19 is a belt-type of conveyor 29, the lower'inner end of which is positioned within the frame 10, as shown, and substantially vertically below the roll 25. Conveyor 29-isforthe purpose of removing the waste tailings of the materials processed and therefore is arranged to receive material from a chute 30 which leads downwardly and outwardly from a hopper section 31 positioned below the outward portionof the magnetic separating roll 15.

Hopper section 32 which is separated from section 31 by means of a dividing wall 33 is positioned directly below rolilS to receive magnetic materials separated from the initial bulk materials by the roll 15 and discharges into an inclined shaker conveyor 34 which is actuated by a vibrating-motor 35.

Rotatably supported on the frame 10 for rotation about an inclined axis extending longitudinally of the assembled apparatus is a tumbler drum 36 having two longitudinally spaced screened

side walls

37 and 38, the first of which is of finer mesh and is located adjacent the charging end ofthe tumbler drum. Drum 36 is open at each end and as' shown in Figure l the conveyor 34 projects into the open upper charging end thereof, which is provided with an .imperforate side wall portion. As the magnetic materials fed by the conveyor 34 are deposited in the drum the same are tumbled about initially in the imperforate side wallportion to dislodge slag particles, dust, and other fines from the larger sized metal pieces and these as well as the initially separated magnetic fines will pass through the open mesh 37 into a collector 39 and thence into a hopper 40 for transfer onto the lower end of conveyor 29. Thethus cleaned and graded magnetic material then passes by gravity into that portion of the drum 36 which is enclosed by the wide mesh side wall 38 and thesmallersized component thereof passes out through the mesh 38 into a hopper 41 for discharge onto a conveyor 42 which extends upwardly and outwardly of one side of the assembled apparatus. The largest sized component of magnetic materials passes out of the lower discharge end of the drum 36 into a hopper 43 for discharge onto a conveyor 44 which extends upwardly and outward ly of the. other side of the assembled apparatus. Positioned below the conveyor 24 and longitudinally spaced from the discharge end of the drum 36 is an enclosure 45: which conveniently houses an engine-driven generator, not shown, for furnishing electrical energy to the magnetic separator 15, the vibrating motors 18 and 3S, and the various conveyor driving motors, and in actual practice I provide means for varying the strength of current furnished the magnetic separator, while the various motors are of the variablespeed type so that the complete assembled apparatus may be operated continuously in a substantially automatic manner without danger of clogging.

In accordance with preferred slag reclaiming practices the reusable reclaimed magnetic material is classifiedinto two'types, name y, that which is suitable for charging into an open hearth furnace and that which is not suitable for charging into an open hearth but which is suitable for charging into a blast furnace. Material not suitable for either-application is classified as refuse and discarded.

In the illustrated processing installation the dust, etc. and the extremely fine metallic particles which pass through the fine mesh 37 of the tumbler drum 36 are classified as refuse and are discharged onto the conveyor 29 along with the larger relatively non-magnetic particles previously discharged by the magnetic drum 15. Subsequently, this refuse material is carried away and dumped or is spread about the slag dump area by a bulldozer, not shown.

Particles of intermediate size, for example, particles too large to pass through the fine mesh 37, but small enough to pass through the coarser mesh 38 are suitable for recharging into a blast furnace and are accordingly collected and saved. Usually it is desirable to position a truck or detachable trailer, not shown, at the discharge end of conveyor 42 to receive and collect the material for subsequent transportation to a steel making plant.

Intermediate sized particles of the type mentioned above usually range in size from one half to three to four inches in principal dimension, and as will be understood it is difiicult to completely remove all slag encrustations from such particles. Therefore, these particles, commonly termed fines are generally not suitable for reuse in open hearth furnaces. Small amounts of slag are not objectionable for blast furnace use; however, the fines are accordingly used for that purpose.

in some applications, slag conditions may be such that appreciable quantities of free slag particles pass through the coarse mesh 38 along with the magnetic fines. In the event that the slag content of the mixture becomes objectionably high it may be desirable to provide additional apparatus for magnetically separating the mixture into its magnetic and non-magnetic components prior to transporting the same to the blast furnaces for charging.

iarticies which are too large to pass through the mesh 38 are discharged at and removed from the open lower end of the tumbler drum 36, and as these particles are relatively heavy and have been subjected to substantial impact treatment within the drum 36, the same are substantially free of all slag, or are at least of such a high proportion of free metal as to render this material suitable for charging directly into an open hearth furnace. Provisions for collection and removal of the open hearth material may comprise trucks or detachable trailers as will be understood.

If desired, the reclaimed material may be allowed to pile on the ground and may be subsequently loaded for transportation to the steel making plant by means of the same crane apparatus, not shown, used for initially loading the bulk slag material into the separating plant.

My apparatus is particularly valuable and advantageous in connection with the treatment of slag formed in current steel making operations in that the apparatus is portable and may be readily moved from place to place, and in that it may be accurately geared to the rate of production of slag so that maximum efiiciency may be realized in .the overall operation. Thus, in the preferred reclamation program it is usually desirable to provide several dumping pits for the molten slag whereby at any particular time one pit may used to receive molten slag, while another pit may contain slag during cooling thercof to workable temperatures, while still another pit contains cooled and solidified slag suitable for processing in apparatus of the type herein described. It is of course desirable to work these pits in rotation so that the overall operation isa substantially continuous one, and hence it is particularly important that the slag processing apparatus be portable to the extent that it may be readily moved from one pit to the other. By my present invention I provide a self-contained separating and treating plant which is adapted for. continuous operation, and which may be readily moved from place to place in accordance with the schedule of dumping, cooling and working of the current slag in the various pits provided therefor about the slag dump area.

The apparatus may be ideally integrated into heretofore accepted and approved slag reclamation programs since it may be serviced and attended by a crane and bulldozer, both of which machines are required for other purposes in the program.

Further advantages of the invention reside in improved structural arrangements of the slag treating apparatus which provide for efficiency in the flow of materials and compactness in the arrangement of components, all of which features are highly desirable in an installation of the type concerned. By positioning the cleaning and classifying drum 36 below the inclined conveyor 24 and by inclining the same in the same direction as the conveyor a compact low assembly is achieve-d which is not only adaptable for transport over rough terrain, but which when in operation performs in an automatic manner the multiple functions of separating out the metallic bearing materials, cleaning such materials, and classifying the same according to size. Thus, the improved apparatus of the invention makes possible, in a practical sense, the processing of large tonnages of granulous slag and refuse material heretofore considered waste with the desirable end result of conserving the metallic values therein.

It will be understood, however, that the apparatus described specifically herein is but a preferred embodiment of my invention. In determining the full scope of the invention, reference should be had to the claim appended below.

I claim:

Portable apparatus for recovering steel scrap and metal-bearing fines from steel-making furnace slag comprising an elongated base structure supported at one end on a transversely spaced pair of crawler tracks, the other end of said base structure being offset in a vertical direction, a crawler-type of swivel truck under said offset end portion of the base, an upright framestructure on said other end portion of said base, a grid supported on the upper portion of said frame structure vertically above said swivel truck and in inclined position sloping downward toward the adjacent end of said base, a sec ond upright frame structure on the remaining portion of said base, a continuous inclined conveyor supported at its upper end on said second upright structure and at its lower end in said first upright frame structure, a hopper below said grid to discharge material flowing therethrough onto said conveyor, said conveyor being inclined similarly to said grid, an elongated tumbler barrel the outer cylinder of which is formed with a pair of longitudinally spaced sections having different sizes of apertures therein, means rotatably supporting said tumbler barrel on said base structure underneath the upper end portion of said conveyor and inclined in the same general direction as said conveyor whereby said apparatus is compact with the upper extremity of said conveyor being of minimum elevation, a magnetic drum rotatably supported on said second upright frame structure longitudinally outward of the discharge end of said conveyor and the charging end of said drum, a continuous conveyor extending upwardly and longitudinally outward from a position below the first of said of said sections which is adjacent the charging end of said drum to receive the screenings therefrom and the non-magnetic components from said drum, and a feeding trough extending longitudinally into the charging end of said barrel to charge the magnetic components separated out by said drum.

References Cited in the file of this patent UNITED STATES PATENTS 1,250,554 Bryan Dec. 18, 1917 1,958,351 Shingshang May 8, 1934 2,264,204 Heckett NOV. 25, 194i 2,276,333 Ovestrud Mar. 17, 1942 2,352,712 Heckett July 4, 1944 2,366,222 Tocci-Guilbert Jan. 2, 1945 FOREIGN PATENTS 600,395 Germany July 21, 1934