US555951A

US555951A - Roasting

Info

Publication number: US555951A
Authority: US
Publication date: 1896-03-10
Anticipated expiration: 1913-03-10

Description

(No Model.) 3 SheetsShee 1;

H. W. HIXON. ROASTING, SMELTING, AND CONVERTING PLANT.

No. 555,951. Patented Mar. 10, 1896.

3 Sheets-Sheet 2.

(No Model.)

H. W. HIXON. ROA$TING, SMELTING, AND GUNVERTING PLANT N0. 555,951.

Patented Mar. 10, 1896 5% ,0 .0 .w P Q M a? N 3 M n v S b b I; W wk AN DREW EGRAHAM. PHUTO-UTNQWASHINGTON. DI;

llwirnn STATES ATENT FFICE...

IIIRAM \V. HIXON, OF ANACONDA, MONTANA.

ROASTING, SMELTING, AND CONVERTING PLANT.

SPECIFICATION forming part of Letters ZPatent No. 555,951, dated March 10, 1896. Application filed June 18, 1895. Serial No. 553,187. (No model.)

To all whom it may concern/. I

Be it known thatl, HIRAM \V. IIIXON, a ci tizen of theUnited States,residin g at Anaconda, in thecounty of Deer Lodge and State of Montana, have invented certain new and useful Improvements in a Combination Roasting, smelting, and Converting Plant, of which the following is a specification.

This invention relates to certain new and useful improvements in furnaces for the roasting or desulphurization of ores; and it consists substantially in such features of construction, arrangement, and combinations of parts as will hereinafter be more particularly described.

The invention has reference more particularly to that class of ore-roasting furnaces in which one or more series of shovels or plows are operated by endless chains or ropes to move the ore gradually along the surfaces of the roastinghearths until finally delivered at one end of the furnace either in a calcined or desulphurized condition. A common disadvantage with furnaces of this general character is that the draft is constantly interrupted by reason of the opening of the movable doors at the ends of the roasting-chambers, which permit the shovels or plows to pass out of one chamber and be carried around to enter the next. Another disadvantage resulting from the construction of these furnaces is that the chains and carriers for the shovels are very seriously injured or affected,

by constant exposure to the heat of the chambers, although in some instances provision is made to subject the same to the cooling action of the external air after being carried through one chamber and before entering the next.

The object of the present invention is to improve the efficiency of the furnace generally, and to overcome the disadvantages above mention ed, and this I attain by the means illustrated in the accompanying drawings, in which- Figure 1 represents a side elevation of an ore roasting furnace having my improvements embodied in connection therewith, and also showing a smelting-furnace and a converter, each being of conventional form. Fig. 2 is a horizontal sectional view, and Fig. 3 is an enlarged transverse sectional view. Fig. 4 is an enlarged sectional detail view showing ,fer the employment of a general ore-reducing plant embodying several roasting-furnaces, each of which has co-operating therewith a smelting-furnace and a converter, but I have herein represented but one of each of these, which is sufficient for the purposes of my present invention.

My improved roasting-furnace may be constructed in a variety of different waysthat is to say, the roasting-chambers and draftfiues may be constructed in a manner best understood by which to obtain the best possible results in practice-and the heating of the furnace may be effected in any suitable manner. Preferably I utilize the waste heat of the smelter to effect the roasting of the ore, and which is conducted to the roasting-chambers through suitable connecting passages or fines.

I construct my improved furnace of suitable brickwork or other fireproof material, and the size or dimensions thereof are such as may be required in use.

Preferably I construct the furnace A with an upper roasting-chamber, 1, and a lower roasting-chamber, 2, each of said chambers being provided with a roasting-hearth 3, eX-' tending usually the full length of the furnace, and in the presentinstance the lower hearth is extended at one end for a purpose to be described. At one end is a feed-hopper a for the ore, and at or near the opposite end of the furnace is an opening I), through which the ore is caused to fall as it is moved along by the plows located in the upper chamber.

In the sides of the furnace suitable air-inlets or doors 5 are provided, which may if desired be controlled by valves or dampers for regulating the quantity of air admitted to the chambers and for inspecting the plows, and

at intervals of the length of the furnace on opposite sides suitable flues 6 are built, which are in communication with the passage leading from the smelting-furnace 00 and which flues communicate with the roasting-chambers, as shown at 7 7, Fig. 3. Thus, by means of suitably-disposed dampers 7 ,the heat from the smelting to the roasting furnace may be easily controlled and regulated. As in this class of furnaces the process of roasting isnecessarily required to be conducted comparatively slow, it is usual to provide stirrers or plows for gradually spreading and working the ore along to the point where the same is discharged from the furnace. Said stirrers or plows as heretofore employed are operated by endless cords or chains passing around drums, and in order. to give the stirrers and their chains a chance to cool from the effects of the f urn ace heat the chains are generally extended and the operating-drums located some distance beyond the ends of the furnace. Also, as constructed and arranged heretofore the ends of the furnace or roasting-chambers have been provided with hinged or flap doors, which are raised by the stirrers in passing through, and very often this opening of the said doors occurs at a time when it is particularly desirable that the draft and heat of the chambers should not be changed or interrupted. Instead, therefore, of providing the ends of the furnace with movable doors I provide each end of the roasting-chambers with a door which remains closed during the operation of the furnace, and which doors are only opened whenever it may be found necessary to gain access to the interior of the charm bers for any purpose whatever. Thus the stationary doors at the ends of the upper and lower chambers are indicated at 10, while the door 11 at the exit end of the lower chamber is moved to the end of the extended hearth and the hearth covered with a suitable cover of iron plates Z Z on the sides and top. By this means all flap-doors are avoided.

As will be observed, the lower chamber is extended beyond the upper one, so as to deliver the roasted or desulphurized ore into the hopper 12, located in the upper part of the smelting-furnace. I am enabled to employ closed stationary doors in the manner shown by reason of the fact that from the construction and arrangement of my devices the shovels or plows are not carried beyond the ends of the chambers at any time-that is to say, as the plows of the upper chamber are being carried to the left those of the lower chamber are carried to the right, and vice versa, and then the plows of the chambers are reversed in their travel, and on the return of the upper ones to the right and the lower ones to the left they each remain inactive or have no effect upon the ore, as will hereinafter appear. Thus the chains or cables 20, which operate the several series of plows 21, are carried around

drums

22 and 23, located at opposite ends of the furnace, the shaft 24 of the drums 22 being provided with a gear-wheel 25,. meshing with a pinion 26, carried by an auxiliary shaft 27, the said latter shaft being also provided with a fast pulley 28 and a loose pulley 29. The shaft 30 of the drums 23 is also provided with a gear 31, meshing with a pinion 32 on another auxiliary shaft 33, and this latter shaft is also provided with a fast pulley 34 and a loose pulley 35. Connecting the pulley or auxiliary shaft 27 and a pulley 36 on an upper shaft 37 is a chain or belt 38, and said shaft 37 carries a larger pulley 39, connecting by means of a belt or chain 40 with a double driving-pulley 41. Instead of the adoption of the fast and loose pulleys it is obvious that I might employ any well-known form of clutch device for throwing the operative devices into and out of their proper working engagement. Passing around said double pulley 41 in an opposite direction to the belt or chain 40 is a similar belt or chain 42, which connects with a pulley43 at the other end of the furnace and corresponding with pulley 30, and the shaft'44 of this pulley 43 has a smaller pulley 45, which connects by means of a chain or belt 46 with the pulleys on the shaft 30 of the drums The beltshifters 50 are employed in connection with the fast and loose pulleys of the drum-shafts, and it is evident that by properly shifting the belts or chains 38 and 46 the operating-chains for the shovels will be caused to move through the roasting-chambers in opposite directions.

The driving-pulley 41 is driven from any suitable source of power to which the driving chain or belt 41 leads.

It is evident that the means herein shown and described for operating the several series of shovels in opposite directions through the two chambers is merely such as I have selected by preference, and it will be understood that I do not confine myself thereto, on account of the many different means which could be adopted instead.

In order to protect the chains or cables as well as the chain-trucks from the injurious effect of the heat of the furnace I form in the hearth of each chamber one or more conduits or passage-ways 60, which extend for the full length of the hearths and which are open at the top, where they are somewhat narrowed or contracted, as shown at 61. I preferably construct the said conduits with cast-iron linings (32, which are first laid in place, and the material of the hearths is then built up around them, and at intervals of the length of the furnace inclined oil-tubes 63 are inserted in the side walls, which tubes lead to the interior of the conduits and are for enabling the bearings of the trucks 64 to be oiled or lubricated from the outside of the furnace.

Any suitable form of truck could be employed, but preferably I construct the same of a frame 65, substantially triangular in shape, and which is provided at each of its lower corners with a bearing for a grooved wheel 66, which wheels travel upon a rail 67 in the bottom of the conduit, as shown. The upper part of the frame of the truck projects at 68 above the parallel sides 69 of the linings 62, and the said upper part is cut out at 70 to receive the shaft 71, which carries the shovels or plows 72. A removable cap '7 3 is secured to the projecting part of each frame, and it is by removing the same that I am enabled to lift out either one of the plow series together with its shaft without having to run the trucks out of the conduits at the ends. Two conduits being preferably employed in each hearth and at suitable distances apart, a convenient means is thus afforded for supporting the plow-shaft between pairs of the trucks. The plow-shaft being thus supported, the plows 7 2 are placed thereon in sets of twos or threes, which are in opposite relation to each other, so as to insure the proper effect upon the ore. Any other preferred arrangement of said plows could be had, and usually I employ distance pieces or tubes 7 5 for maintaining them the proper relative distances apart. It is, of course, understood that the chains or cables which propel the trucks are also contained within the conduits, and from the narrow or restricted longitudinal openings in the hearths it will appear that neither the trucks nor the chains to which they are attached are subjected to any very great degree of heat. In this way the chains or cables do not pull apart, and expensive breakdowns are avoided.

It is obvious that inasmuch as the longitudinal chains or cables are first operated from one end and then the other the ore would be simply carried back and forth on the hearths, unless provision was made to insure the feeding of the same toward the delivery end of the lower hearth after having been carried down the full length of the upper hearth and forced through the opening 17 therein. Therefore to insure the proper working and results it is necessary that after the several series of plows have moved the ore along in one direction they must be tripped as they are reversed, so as to pass entirely clear of the ore on their return, and while various devices could be resorted to for this purpose I prefer the construction and arrangement thereof such as I have herein shown. Thus the propelling chain or cable for the truck passes through bearings 85, formed in the legs of the trucks, and the said chain or cable is provided with nuts or projections 87, 88, 89, and 90, the said nut or projection 87 engagin g the truck as the chain is moved in one direction, and the said nut or projection 90 engaging the truck when said chain is moved in the opposite direction. The nuts or project'ions S8 and 89 are arranged centrally of the other two and a sufficient distance apart to receive between them the free end of a leverarm 91 pendent from the shovel or plow-shaft, and inasmuch as the said shaft is a rocking one it is evident that when the draft on the operating-chain is in one direction the shovels or plows will be held down upon the hearth,

but as soon as the draft is changed to the opposite side the direction of the truck will be altered and the plows elevated in an obvious manner.

In connection with my improved roastingfurnace I employ a fume-collecting chamber 95, which communicates either directly with the roasting-chambers or else, as shown, by means of connecting-fines 96, with two of the vertical side fines. The said flues 96 are provided with hoppers 97 which empty into the lower roasting-chamber by means of connecting-pipes 98, and which hoppers are for the collection by gravity of the dust or small particles of valuable ores which may be carried off with the fumes. Also in connection with my improved roasting-furnace I employ at the opposite end an ordinary converter 100, and the metal is received from the smelting-furnace into a ladle 101, which latter is then moved bya traveling crane and the contents thereof tipped into the converter and subj ected to the ordinary converting step of the well-known metal-reducing process.

From the foregoing description it is thought the construction and operation of my invention will be thoroughly understood, and while I have herein shown certain preferred details in the general construction and arrangement of the several parts it will be understood that I am not limited thereto, owing to the great number of immaterial changes which could be resorted to in practice.

Having thus described my invention, what I claim is-- 1. An ore-roasting furnace comprising a roasting-chamber, and trucks traveling from end to end of the latter, a shaft supported by the trucks, plows carried by said shaft, an operating-chain for the trucks provided with projections, a short distance apart, and intermediate movable devices operating in connection with said projections and in movable connection with or pendent from the shaft, substantially as described.

2. An ore-roasting furnace comprising the trucks and their shafts, the plows carried by the shafts, the operating chain or cable provided with the nuts or projections, the triangular frames and the lever pendent from the shaft, the whole operating substantially as and for the purpose described.

3. An ore -roasting furnace comprising a roasting-chamber, and trucks traveling from end to end of the latter, a shaft supported transversely of said chamber upon the trucks, a lever-arm pendent from the shaft, and an operating chain or cable for the trucks in movable connection with said lever-arm, and provided with projections a short distance beyond and on opposite sides of said movable connection, substantially as shown and for the purpose described.

4. An ore-roasting furnace comprising upper and lower roasting-chambers having each of their ends closed by a stationary door, series of plows in each chamber, and movable trucks constructed of triangular frames and supporting the ends of the shafts upon which said plows are carried, and removable caps or blocks for securing the shafts in place upon the trucks, substantially as shown and for the purpose described.

5. An ore-roasting furnace, comprising the roasting-hearths constructed with the longitudinal passage-ways or conduits, the trucks moving in said conduits and constructed of triangular frames provided at their upper ends with removable or detachable caps or blocks which project above the said ways or conduits, shafts mounted in the upper ends of said trucks transversely of the hearths and