US1176878A - Process and apparatus for charging furnaces. - Google Patents

Description

L. 0A ANDERSON. PROCESS AND APPARATUS FOR CHARGING FURNACES.

APPLICATION FILED 0015,1914.

Patented Mar. 28, 1916.

2 SHEET$SHEET I.

ooooooooooo Inverziar L. D. ANDERSON.

PROCESS AND APPARATUS FOR CHARGING FURNACES.

APPLICAIION FILED OCT-5.1914.

Patented Mar. 28, 1916.

2 SHEETS-SHEET 2- ,fiavczzfar Wraaaas constitution.

UNITED sTATEs PATENT OFFICE.

LESLIE DOUGLASS ANDERSON, OF MIDVALE, UTAH, ASSIGNOR TO UNITED STATES SMELTING,. REFINING & MINING COMPANY, CORPORATION OF MAINE.

Specification of Letters Patent.

Patented Mar. 28, 1916.

Application filed October 5, 1914. Serial No. 865,140.

residing at Midvale, in the county of Salt Lake and State of Utah, have invented certain new and useful Improvements in Processes and Apparatus for Charging Furnaces; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

' This invention relates to a process for charging the furnaces-of ore treating plants where different grades and classes of ore are to be treated, individually or together, and these various kinds of ore, together with the fluxing, reducing and treating material are separatelystored in bins preparatory for treatment.

The special treatment necessary for lead and copper ores has limited the width of the blast furnace by the :air pressure which it is practicable to apply at the twyers. The length, however, may be varied considerably and such length depends principally upon the quantity of ore which it is desired to treat. For the sake of tonnage in a furnace for lead ore the" length is usually three to four times the width, while a furnace for treating copper may be made much longer than the lead treating furnace. With such a long, narrow furnace, which for convenience will be termed an elongated furnace, it is diflicult to obtain a uniform distribution of the charge throughout the entire length of the furnace. The constitution of the components which go to make up the charge are definitely known and the proportion of each component should be accurately measured in order to obtain the best reduction of the metal and to get a slag of a def'mite In the furnace treatment of metals the reduction is better and more uniform if the components of the charge are homogeneously mixed and uniformly distributed throughout the length of the furnace. In a copper furnace and especially a lead furnace, it is very important that the components be uniformly distributed throughout the length of the furnace.

For many years the charges were shoveled into the furnace by hand, and in fact many furnaces are hand charged today, which method made it possible for the workman to judge by the eye where to place the components to get a uniform distribution. The workmen who did the furnace charging had to be highly skilled and therefore, such a system entailed an enormous expense. later development produced furnace chargmg cars whose dimensions approximated the inside dimension of the furnace and the components were brought in buggies and mixed in beds and then evenly distributed throughout the length of the car by hand and then these cars were run over the top of the furnace and their contents dropped all at j ffoltce into the furnace. This system also was e:

pendent on skilled hand labor, and was very expensive.

One object of the present invention is to provide a process for charging furnaces which will do away with skilled hand labor and enable the components of the charge to be handled in such a manner as to uniformly distribute them throughout the length of the furnace. Inaccordance with this object, one feature of the invention contemplates arranging the components of a charge in layers of substantially uniform length to form a body of material. which is approximately the length of the furnace to be charged, and subsequently depositing the body in the furnace as a unit, the compo nents being mixed throughout the length of the body either before or during the deposit in the furnace.

In practising the process in its preferred form, the components of the charge are arranged in layers to uniformly distribute each component throughout the length of a body of material which has a length substantially the same as that of the furnace to be charged, and the layers of material are then mixed, while maintaining the length of. the body, to secure a body substantially the length of the furnace to be charged, in which the components of the charge are uniformly and homogeneously distributed. This homogeneously mixed and uniformly distributed body of materials is then taken as a unit and deposited in the furnace, preferably in such a manner that an excess of material will be deposited along a central line parallel to the length of the furnace, thus insuring a uniform treatment of the charge in the furnace.

These and other features of the invention will be readily understood from the following detailed description of the apparatus illustrated in the'drawings, and'the manner in which it is utilized in practising the method above outlined.

, In the drawings, Figure 1 is a front elevation showing more or less diagrammatically a preferred form of apparatus for practising the invention, and Fig. 2 is a similar side elevation, partly in section.

In the apparatus illustrated, the bins A, A A etc., which are provided for holding the different classes of ore, flux, coke, etc, are elevated above the lorry car C so that the material in the bins will be fed by gravity. Although only three bins are shown, these bins are generally arranged in rows and suflicient in number to contain the necessary supply of charging ingredients for several days run. The general arrangement and elevation of the bins, the elongated furnace B, the lorry car C and charging car D depends upon the topography of the ground upon which the ore treating plant is located,

since material from a bin could be elevated by suitable hoisting mechanism to a lorry car as well as be fed by gravity. The cars also could be run up inclines to give them the proper position above one another and above the furnace if the bins and loading tracks were not elevated above-the furnaces.

The storage bins A are supported by a trestle work above a loading track 16 which is also supported by the trestle. The bottoms of the bins have a pair of compartments a, a at their dischar e mouths which sup )ly material from the endless conveyer feeders 1 and 2 respectively. The feeders 1 and 2 are positioned far enough above the loading track to permitthe lorrycar C to travelbelow them when moving along the bins to collect the components of the charge. The components of the charge are discharged from the feed-.

. ers 1 and 2 into a measuring hopper 12 sus pended in the lorry car C and are uniformly distributed throughout the length of the hopper as discharged. "To secure this distribution, the' combined efiective feeding width ofthe conveyer feeders 1 and 2 is substantially equal to the length of the hopper 12. The hopper 12 has a length sub-v stantially the same as the length of the elongated furnace B, so that the combined effective feeding width of the feeders is substantially equal to the length of the furin to a pairlof N as the length of the body, are substantially maintained until the body is'deposited in the furnace.

The conveyer feeders consist of a pair of endless belts which travel over a pair of guiding drums 8. The guiding drums 8 at the receiving end of the conveyer are mounted on a driving shaft 5 which is connected bya train of gearing 4 with a. connecting gearing 3. The lorry car is preferably provided with an electric motive equipment and has a feeder operating motor 11 mounted on the body of the car at the rear of the measurin hopper 12. The motor 11 has a gear 7 whic is positioned to mesh with the feeder connecting gear 3 when the hopper 12 is in mg uring hopper 12. The-bins A have a door 10 located above the feeders which give access to the feeding-compartments of the bins to make repairs, and also to place the material in a condition to feed properly.

In collecting 'a charge for the furnace each ingredient should be accurately weighed, in order to properly balance the amount of flux and reducing material to treat the ore. With the apparatus shown in the drawings, the material is measured. by weighing it as it is discharged into the hopper 12 of the lorry car. For this purpose the hopper 12 is suspended from a scale beam 14, and the beam'14 is connected with an indicating beam 15 mounted in the rear end may be desirable in some cases to measure the material with any of the well 'known and approved types of measuring and distributing feeders such as the piston feed, the shaker feeder, or the arc-type discharging gate.' When using such types of apparatus, however, they should be constructed to uniformly distribute the ingredients being handled throughout the length of the receiving hopper in which the charge is collected.

In the smelting of some metals, it may be sufiicient if the charge of a lorry car, consisting of ingredients arranged in layers uniformly distributed throughout its length, be discharged directly into the furnace, but in the treatment of copper and especially of lead, it is desirable that the ingredients be thoroughly mixed before being placed in the furnace in order to get the proper reduction. An efficient and successful type of mixer is shown at E. After the charge is deposited in layers in the hopper 12, the car C is run directly over the mixer E and by means of the bottom doors 22 and 23 of the measuring hopper 12,-the charge is dumped I portion, can be governedso as to give a homogeneous mixture.

- The mixed charge may be received in the hopper 17 of the charging car D and the mixer is so arranged that the mixed material is uniformly distributed throughout the length of the hopper 17. The length and preferably width of hopper 17 are substantially the same as those of hopper 12 and as stated above, these dimensions approximate the inside dimensions of the furnace to be charged. The body of material formed in the hopper 17 is thoroughly mixed and is in substantially the same shape as that in which it is treated in the furnace. In case it is practicable to run the lorry car over the furnace, the mixer may then be located over the furnace and the charge dumped directly through the mixer into the furnace from the lorry car.

Although a deflector mixer has been described, the invention is not" limited to the use of such a mixer since any of the approved types of mixers could be employed" which would receive the charge'and, homogeneously mix and uniformly distribute it throughout the length of the bed below;

Any of the preferred type of charging cars may be used and these generally have an electric motive equipment. employed the axles are provided with two sets of wheels. The inside set 18, which run on track 20 are larger in diameter than the set 19, on the outside of the car track, in order vto carry the weight of the car and hopper when the car is being loaded and while in transit from the furnaces to the mixer. The smaller wheels 19 run on track 21 at the side of the furnace so that the car D is supported at the-sides of the hopper 17 while it is discharging into the furnace. Thehopper 17 has the usual bottom discharging mechanism so that when it is placed over a furnace the contents may be dumped all at once.

In a typev The physical structure of the furnace and the character of chemical action that take place in the charge during treatment cause the central portion of the charge to sink faster than the portion around the sides, so that in placing the charge in the furnace it is desirableto so locate the material that it will sink uniformly and all parts of the charge get the same treatment. By meansof the chargin mechanism described, a much more uni orm and accurate distribution can be obtained than by any other charging system known to the inventor. It

will be noted that the feeders are arranged i to feed the? material at about the center of the lorry (in so that the material will be higher at the center than at the sides when placed in the hopper. In the dumping of the charge from the measuring hopperthrough the mixer E the deflectors 24 are arranged distribute an excess of material along a vertical central plane parallel to the length-"of the receiving receptacle. If the material is deposited in the charging car before being placedin the furnace, the transfer ofthe material, from the charging car into the furnace will approximately maintain the excess of material roundedabout the vertical central plane of the furnace. By arranging successive ch arges in the furnace in this way, each charge will sink down and reach the furnace bottom. as a unit and all parts of the charge will be uniformlyfltreated. t

In carrying out the process, the lorry car is run along the rows of bins A to get the various components of the charge. At each bin the gei'gr 3 is brought to meshwith gearing on the motor 11 and the operator then setsthe scale beam and operates the aprons to get a definite amount of each component.

.These components are arranged in layers uniformly distributed throughout the length of the hopper 12. The lorry car with its weighed charge is then run over the mixer E which may be located over a charging car D or elongated furnace B, and dumps. The blades of the mixer are set at such an angle as to get a thorough mixing, which angle may vary for different characters of the components to be mixed. The charging car when used, upon receiving the intimately mixed charge from the lorry car, is run over the furnace and the charge is dumped all at one time.

By the process. outlined above, the ore along with the fluxes and reducing agents for treating it are assembled together, homogeneously mixed and uniformly distributed throughout the length of the furnace in which they are treated. Each ingredient of the charge is measured, and all of the measured ingredients are grouped together to be treated as a body. The charge is deposited in the furnace in such a shape that in sinkelongated furnaces which comprises distric buting the components of the charge nlaye.

is claimed as new is 1; The process of charging elongated furnaces which comprises distributing the components of 'a charge inu scparate portions having a substantially uniform length to form a body of material approximately the l i length of the furnace to becharged, mi xing Qthe materialto, form abody of material of -r approximately the length of the fu rna'ce in tributed and homogeneously mixed, and d e Which the ingredients are uniformlyydispositingfthe mixed; body of material unifo'rmly throughout the length of the furnace.

,2. The process of charging elongated furnaceswhich comprises'uniformly distributing the components of the charge in layers hav ing a substantially uniform'len'gth to form a body of material, mixing the body of mate rial'while maintaining its length to form a body of material in which theingredients v ofvthc charge are uniformly distributed and homogeneously. mixed, andudepositing the mixed body of material'uniform'ly throughoutthe length of the furnace.

3. That step in the process of charging a of substantially uniform length toform body of material having approximately f "the length of the furnace tobe" charged preparatory'to placing'the body into the furv-nace.

4 The process of chargingelongated furntegers 'naces which comprises" distributing components of a chargein separate portions having ;a substantially uniform length to form a material While ma'ntaining "its length to homogeneouslymix and 'uniform'ly distribute the components of saidbody, and depositing said body as a unit inthefurnace.

- naces which comprisesdistributing the comi yh'aving a substantially uniform lengthto "form a body ofmaterial approximately the length of the furnace'to'be charged, mixing the body 'ofmaterial to-form' a body of material in whichthe components are homogeneously mixed, and distributing the mixed 'body inthe furnace with an excess'of ma'te-' rial about a vertical central planeparallel" with the length of the furnace, so tliatthe charge will receive a uniform furnace treat- 'inent. 1 i 6. The process of ohargingjelongated;fur-

f having a substantially uniform; length to form a body of material approximately the length of the furnace to be charged, mixing a the body "of material whilef maintaining v its length to form a bodyof materialin which the ingredients are uniformly distributed and homogeneously mixed, I and depositing the mixed 'body of material in the furnace with an excess of material'rounded about a verticalv central plane parallel to the length of the furnace whereby the body yvill sinkas. a unit toobtain a uniform furnacetreat- A, LESLIEDOUGLASS ANDERSON.

"Witnesses: v d

s. OR N RYAN j N. THOMPSON."

V 'po'nents" ofacharge in separate portions names which comprises uniformly distributing the components of aflcharge in layers 7 body .of material approximately the length of the furnace to be charged, mixinggthe 5. i The process ofcharging 'elongatedfur-

Images