US2151683A - Method and apparatus for casting copper anodes - Google Patents

Description

mas

March 28, 1939.

BUSCHE METHOD AND APPARATUS FOR CASTING COPPER ANO Filed MaylB, 1957 [NVENTOR v Aida/pile Burr/1e ATTORNEY 35 anode and cathode surfaces.

so suit Patented a... 28, 1939 PATENT orrlce METHOD AND APPARATUS FOR CASTING COPPER ANODES Adolphe Busche, Woodbridge, N. J., assignor to American smelting and York, N. Y., a corporation of New Jersey Refining Company, New

I Application May 12, 1937, Serial No. 142,080

6 Claims.

In the production oi electrolytically refined copper, it is customary to cast the anodes to be refined by introducing the copper. into the anode molds by meansof a ladle which receives the 5 copper directly from the anode furnace.

The anode molds are mounted customarily on some type of casting wheel which brings the molds successively under. the discharge of the ladle whereby the copper flows from the ladle 10 into each successive mold for filling the latter. The customary construction of the ladle provides for an end discharge of the copper from the ladle intothe mold beneath it, and, consequently, it is necessary to stop the rotation of the casting wheel 16 as the mold is filled thereby bringing each mold to a stop beneath the discharge end of the ladle until the mold is filled. When the mold'is filled, the wheel is actuated again until the next mold of the series is brought into filling position.

' g This intermittent operationof the. casting wheel and the end pouring of the copper from the ladle are opento decided disadvantages.

Thus, when the wheel is started after e ch mold is filled, the copper in the mold is still molten or 25 plastic so that the. inertia of the copper results in a tendency of the copper to surge against the side of the mold when the wheel is started thereby producing a rolled edge on the cast anode.

The presence of such rolled edges acts to diminish, 3 very materially, the ampere efficiency of the refining cell,

it is impossible to obtain a positioning of the cathodes with respect to the anodes so. as to have an equal distance between all portions of the Where the, rolled edges are present on the anodes, the excess cop per along such edges presents a less distance between such copper and the cathode surface than is present between the remaining portions A 40 of the electrode surfaces, so that there is a tendency to build up on the cathodes excrescences or projections of 'metal opposite to the rolled edges of the anodes, which reduce the path of current travel from the anode to the cathode, tending to short circuit the cell and to increase gold and silver losses.

The elimination of such rolled edgeson the anodes becomes, therefore, a very desirable re- A further disadvantage of the usual practice of casting copper anodeslies in the fact that when the anodes are operated so as to be stationary below the ladle, there maybe variations in the pouring time which hasan important eflecton because in the refining operations,

the application of the necessary mold dressing to the succeeding molds.

In this connection it is to be borne in mind that a mold wash is applied to each mold before the copper is poured into the mold. The mold wash I comprises usually a thin slurry of bone-ash, which slurry obviously is of a substantially constant density or specific gravity for each mold.

' The molds of course are hot, so that if there should be a substantial variation in the pouring time for the molds as they reach pouring position, the succeeding molds will have the mold dressing applied thereto for varying periods of time before the molds are filled with the copper. This may result in an insufilcient drying of the mold dressing, or an excessive drying thereof. The former condition is conducive to trouble upon the application of the copper to the mold, because of the presence of moisture in the mold dressing or an inefiicient adherence oi the mold g dressing to the mold. When there has been excessive drying of the mold dressing, there is also a tendency of the dressing to separate from the mold because of caking or spelling of the dressing.

In either case there may be excessive inclusion of the molddressing in the castings, or there may be difiiculty in discharging the castings from the molds.

Aiurther disadvantage in the usual practice of discharging the copper from the end of the ladle into the anode molds lies in the fact that the copper reaches the mold in a position which is towards what will be the bottom of the anode. Each mold is provided at what is to be the top of the anode with portions which define the contact lugs of the anodes when the latter are in operation in the refining cells. It is necessary to have these lugs well formed in order for efficient contact to be made between the anodes and the bus-bars of the cells. This means that the por- 40 tions of the mold which define the anode lugs should be well filled with copper and, accordingly, therefore, the copper should be fully liquid when it flows into the lug recesses of the mold. In ac cordanee with the usual methods of casting, the

copper flows backwardly from the point of pouring which means it has reached its lowest casting temperature when it is ready to flow into these lugs. In order to have suflicient fluidity to fill these lug portions in a satisfactory manner, it is evident the copper must be well superheated when placed in the mold.

This superheat, however, tends to produce a localized burning of the mold where the stream of copper strikes the mold, the stream usually being a The invention will required to start and to stop the casting wheel for each mold.

The present invention provides an improved method and apparatus for casting copper anodesfor use in the production of electrolytic copper, which will obviate the above, and other, disadstopping of the casting wheel when each mold is to be nlled. In accordance with the present invention, the copper is poured into the molds from an improved type of ladle which enables the casting wheel to be. operated in a continuous, instead of in an intermittent, manner.

Further objects of the invention will become apparent as the description proceeds and the features of novelty in the appended claims.

In accordance with the present invention, the copper is poured into the molds froma ladle which introduces the copper preferably as a plurality of small streams, laterally of the mold, that is to'say in line with the direction of travel of the molds Pouring the copper in .this manner prevents localized burning :of the-molds and enables an eifective cushioning action to be set up by the body of copper in the mold thereby facilitating the production of anodes of uniform surface.

Furthermore, pouring the copper in this manher into the molds enables themolds to be.

without any breaki'n the operation of the wheel. so that the eifects of inertia incident'to stopping and starting the wheel during casting with the consequent productlonof the rolled edges referred to above. operation of the casting duce the proper mold for the production of anodes of standard Furthermore thecontlnuouscperation of the castingwheelpermihaclosecontmlofthetemperature of the molds, all molds being at the same temperature when the application of the mold dressing whereby .a uniform disposition and adherence of the mold dressing to the molds is obtained. and, all molds arrive at the pouring position at the same temperature.

be understood more particularly by reference to the accom nying drawing which shows a dlagrammatical perspective view of the improved ladle and tilting mechanism therefor, the ladle being shown in position ready to pour copper into the anode mold. Referring more particularly to the drawing, the ladle comprises the metal receiving, or reservoir, portion 2, which receives the metal from an anode furnace (not shown) and which communicates with an elongated discharge launder extending over the molds longitudinally there of, one of the molds being indicated at 0. The mold I is understood to be one of a series of molds mounted on any conventional type of easting wheel (not shown) so that the longitudinal distribution will be pointed out in" detail on the cast anode, the small l4 and It, and

. inder' 2|.

amoimt of copper. into each theyaresubiectedtoapproximately axis of the molds will extend radially of the casting wheel. In view lng' wheel is of any standard construction, it is not indicated on the drawing, the arrow 8 showing the. direction of travel of the molds.

The reservoir 2 of the ladle communicates through passage with the discharge launder I, the latter being provided with a plurality of laterally disposed discharge channels 36, which are distributed so as to avoid localization of impact of copper onto the mold but which are adapted to pour a plurality ofsmall streams of copper into the mold, which streams are'cushioned by the copper in the mold, splashing of the copper being minimized thereby with attendant avoidance of the. formation of fins on the edge.of the cast anodes. Furthermore, the ofv copper in the mold lssuch that of the fact that the castthe copper is fully fluid when it flows into the lug portions 38 of the mold thereby producing well defined lugs for the anode which result in effective contact with the anode bus-bars during electrolysis of the anodes. The number of channels for the discharge of-the copper is not, necessarily, a fixed number, this being determined by the particular operating conditions.

In addition to preventing the formation of fins streams of coppe flowing" from the discharge channels 38 of the ladle prevent loc overheating and burning of the mold.

The reservoir portion I of the ladle is provided with a member It for attachment of a tilting cable II, which cable passes over sheaves of a piston rod ll, operating an hydraulic cyl- The flow of hydraulic fluid to the cylinder 28, is controlled by valve 22, which is operated by a lever 24 in'the usual way, the fluid inlet and outlet lines for the valve being lndi-' tilting mechanism, so thatcopper will flow from as a plurality of fine streams into the mold 0 thereby filling the latter.

It will be observed that the copper enters the mold inline with the direction of travel of the moldas indicated by the arrow 8, and that the streams of copper are mold. Since the time of pouring is proportioned to the speed of movement or travel of the molds, the mold, which may be of standard size of approximately 36" x 36" x 1%" and holding 850 pounds of copper, may be filled without interruptlng the speed of travel of the mold, sothat the mold will be illled with copper by the time it passes out from beneath the launder 4 of the ladle; whereupon the to stop the flow of copper from the launder until the succeeding mold reaches pouring position,

casting wheel thereby being'continuously rotated throughout the operation.

This continuous rotation of the wheel avoids the production of rolled edges on the cast anodes due to the eil'ects ofinertia of the metal incident to starting and stopping the rotation of the easting wheel, thus assuring increased eilciency in which is connected to the end ladle is tilted backwardly.

well distributedover the the electrolytic refining more, the continuous operation of the casting wheel means that the pouring time so that themold dressing is applied under con reservoir portion when the launder whereby the said mold may be filled stant conditions to each empty mold prior to its reaching pouring position; and also there are pro-' duced anodes of more uniform surface than have been obtainable uniformly by the pouring pro,- cedure which has been regarded as standard practice, aspreviously outlined herein.

The tilting mechanism described above affords,

a means for proportion'ing the pouring rate to the rate of travel of the mold so as to enable each mold to be filled launder 4 without mold.

What is claimed is: v

1. A ladle for introducing copper from an anode furnace into comprising a reservoir portion, a launder portion extending from the reservoir portion over the mold and adapted to receive metal from the stopping the movement direction, mounting means for the ladle enabling the said ladle to be tilted laterally, laterally disposed discharge means and in thin streams as the mold moves, beneath with metal while continuing its movement beneath the launder, and means for tilting'the mdle to inoperative position upon completion of the I filling of the mold.

adapted to. receive molten furnace, a launder communicating with the reserhaving a multiple spout adapted to discharge metal in thin streams filling position,

2. A ladle adapted for use in casting anodes for electrolytic refining comprising a reservoir portion metal from an anode voir portion, the said launder from the ladle into an anode mold laterally thereof without interruption to the travel of the mold beneath the ladle as the mold reaches and means for tilting the ladle laterally between operative and inoperative positions relativeto the mold as the mold reachesand leaves filling position.

3. A method of casting copper anodes for use which mode in the production of electrolytic copper comprises progressively moving a series of a a aioneas of the anodes; furtheris constant, I

during its passage beneath the of the a series of traveling anode molds the ladle is tilted in one in the launder for distributing metal into the mold laterally thereof.

molds into casting position a substantially uniform speed, filling the molds with copper by leading thereto molten copper from an anode furnace through a' suitable ladle and pouring. the copper from the ladle 'lnaplurality of streams in line with the direction of travel of the mold, and adjusting the pouring rate to the speed of travel of the molds so as'to fill completely each mold with 4. Apparatus in the production of electrolytic copper comprising the combination with a molds disposed for able conveyor, of a ladle for supplying copper to the mold from a melting furnace, the said ladle 'comprising a multiple discharge spout having outlets adapted to deliver a'plurality of fine streams I of copper to'the mold in line with the direction of travel of the mold, the said outlets being arranged with;respect' to the mouldiso tribute the copper uniformly in the mold as the mould moves beneath the ladle.

for casting copper anodes for use 5. Apparatus 'in the production of electrolytic copper which comprises the combination with-a plurality of anode molds disposed for continuous travel on a suitable conveyor, of a ladle for supplying copper to the mold from a melting furnace, ally directed discharge openings adapted to deliver a plurality of fine streams of copper to the mold longitudinally of the mold and distributed uniformly over the surface of the mold, and mechanism for controlling the speed of delivery of copper from the ladle in accordance with the rate of movementof the mold so in the rate of movement of the mold; v V

6, A process for casting copper anodes which comprises introducing copper as a fine streams'into a continuously traveling 1 anode mold in mold, the said streams being he cushioned by copper already in themold for obviating splashing of the copper and formation 'of fins on the resulting cast anode.

as to disline with the direction of travel of the sufflciently fine to copper without stopping the travel of the molds.

for casting copper anodes for useplurality of anode a continuous travel onv a suitthe said 1 ,ladle comprising a. discharge spout having laterthat the mold will become iilled with copper as it passes beneath the said spout-without variation ,0 plurality of mourns suscnn.

Images