US806046A - Method of converting matte. - Google Patents

Description

No. 806,046. PATENTED NOV. 28, 1905. I

' R. BAGGALEY & C. M. ALLEN.

METHOD OF CONVERTING MATTE. APPLIOATiON FILED AUG.15,1904. RENEWED APR. 6,1905.

WITNESSES v PATENTED NOV. 28, 1905. R. BAGGALEY 6: G. M. ALLEN. I METHOD OF CONVERTING MATTE. APPLIOATION 31mm AUG.15,1904.

RENEWED APR. 6,1906.

2 SHEETS-SHEET 2.

m iiilii $1! witnesses mvzu'rons UNITED STATES PATENT OFFICE.

RALPH BAGGALEY, OF PITTSBURG, PENNSYLVANIA, AND CHARLES M. ALLEN, OF LOLO, MONTANA; SAID ALLEN ASSIGNOR TO SAID BAGGALEY.

METHOD OF CONVERTING MATTE.

Specification of Letters Patent.

Patented Nov. 28, 1905.

v Original application filed J111y 18, 1904, Serial No. 217,112. Divided and this application filed August 15, 1904. Renewed April 6, 1905.

Serial No. 264,113.

the city of Pittsburg, in the county of Allegheny and State ofPennsylvania,and CHARLES ALLEN, of L010, in the county of Missoula and State of Montana, have invented a new and useful Method of Converting Matte, of

which the following is a full, clear, and exact description, reference being bad to the accompanying drawings, forming part of this specification, in which Figure 1 is a vertical longitudinal section of a converter suitable for practice of ourinvention. Fig. 2 is a vertical cross-section on the line H II of Fig. 1, and Figs. 3 and 4 are like views showing a modification.

The present specification is a division of an application, No. 217,112, filed by us on July 18, 1904. p

The object of our invention is to reduce the cost of producing blister-copper by eliminating the present heavy expenses for converterlinings and to transform this serious expense iuto'a source of profit, thus constituting a new method of converting mattes.

In the practice of our invention three things are of importance: first, that the converterwalls should be either composed of heavy metal blocks of such relative thickness that they cannot be destroyed'durin'g the process or preferably of heavy metal blocks with a light basic interior. lining which will also resist injurious action by the oxidized iron, such as must always result where silica is used in direct contact with matte that contains iron and also to the end that the converter-walls may be comparatively clean and hot after the layer of ore has been consumed and dissolved by the action of the matte and heat; second, that the converter shall be so designed and made of such materials that it may be able to withstand without injury the great heat of the process, as well as the intensely corrosive action of the fiery lowgrade matte; third, that the converter may be able to withstand this exacting service 'without unduly abstracting and dissipating practicing our invention is composed of heavy metal blocks whose thickness bears a proper relative proportion to the molten bath to be held, as fully, explained in the application, Serial N 0. 200.943, filed March 31, 1904.

The water-jacketed converter shown in Figs. 3 and 4 can be used in practicing this art; but we recommend that at the laterstages of the process the flow of water through the jackets be greatly reduced or preferably shut oif altogether for a time in order to prevent any excessive abstraction of heat from the vessel.

Many efforts have been made in the past to utilize mineral-bearing ores as the source of silica forfl'uxing the iron of copper matte after the latter has been oxidized by the converting-blast. As a rule these efforts have taken the form of the use of pulverized ores mixed with clay or some other bonding agent and Water into a plastic mass with which the converter is lined. In John Holways patent,

No. 234,129, dated November 9, 1880, a proccss is \described wherein silicious and slagproducing materials are added to the matte.

Metalliferous substances containing the nee-- essary slag-producing materials and containing also valuable metals in such small quantities as to make them unfit for treatment by themselves were described as preferable. In actual work John Holway reported to the London Society of Arts that he used quartz sand impregnated with about five per cent. of oxid of iron. He fed this with a shovel into the converters mouth, but without success.

Attempts have been made to supply silica the molten bath. This process has also're'- mained to the present day unused.

At Aguas Galientes avery unusual OI'GOb, tained from the St. Gertrude mine in Pachuca, Mexico, has been utilized as a successful converter-lining and fluxing agent. This ore contains approximately eighty per cent. of

pure quartz, twenty per cent. of almost pure alumina, and from eight dollars to fifteen dollars per ton in gold values, which latter are finely and evenly disseminated through the quartz. The ore is pulverized in Chilean mills, is then mixed with suitable proportions of water, and in this form it is rammed as a lining into very large converter-shells, usubody of molten converter-matte was poured into the converter upon it. Ralph Baggaleys Patent No. 746,260, dated December 8, 1903, described a like process to that described in No. 746,241, except that it utilized mineral-bearing silicious ores as the fluxing material.

In all former efforts to use ore for converterlinings or to utilize either ore or silica by introducing it through the twyers or into the mouth of the converter the aim has been to satisfy the iron in a high-grade convertermatte, and by this means to increase the percentage of the mineral contents, which would also have the efieet of decreasing the volume of the molten bath correspondingly through the separation of slag. All such attempts to use ores for lining have been very costly, because such ores must be first pulverized, which in itself is very expensive, then thoroughly mixed with water and, with one exception, with clay, and thereafter they must be tamped or compacted into the converter-shell with rammers, in order that they would remain firmly in position during the converting process. It has been found that the best results are obtained if only a moderate quantity of water be used; but in order to secure such comparatively dry plastic mixture in its position in the converter-shell a large amount of hand-labor has been required in the work of ramming it. This process has also required the expenditure of money for coke with which to dry out the linings before use, and inasmuch as coke is always expensive in localities where copper ores are treated'this has added materially to the cost. In actual practice it is found that only a small proportion of such lining can be used until the destructive action must cease, else the destruction of the metal converter-shell will quickly follow, inasmuch as the corrosive action of the bases is not and cannot be distributed evenly over the surface of the acid lining. On the contrary, the iron of the matte attacks the silica of the lining much more at some places than it does at others. I Hence when it has weakened it at any one point to the extent that the metal shell becomes heated to a red heat further converting action must cease or serious and permanent injury to the shell will result. hen a lining thus becomes weakened, it necessitates the removal of a large amount of the same in order to prepare the shell for relining, and the portion removed usually is so permeated with fusible material from the former charges thatit is unfit to be used again for a lining material. It must be smelted as a means of recovering its contained values, which process involves additional expense. It is estimated that each converter-lining costs at least forty dollars. If carefully prepared, it may last for from seven to twelve blows; but if carelessly applied it may be destroyed in a single blow or in two or three blows. Under the most favorable circumstances a very large proportion of the material contained in each lining is useless for effective work, because the iron of the matte usually eats holes through certain portions of it, thus rendering the balance useless for fluxing purposes. The life of such a lining will be very largely governed by the care and the uniform ramming exercised by the workmen while placing it in position. The constant aim has been to make the lining as durable as possible as ameasure of economy. This has led experimenters to avoid everything that would render the lining friable or easily dissolved by the molten bath, and it has therefore been considered necessary to avoid the use of all ores and all lining materials that carry basic elements or compounds, inasmuch as these would contribute to its rapid destruction. Every other consideration has been sacriliced in the effort to maintain the life of the lining to the utmost. By our invention this practice is entirely reversed. Inasmuch as we depend upon the destruction of the lining material as the means whereby we extract and recover mineral values contained in the ores of which we make the lining economy demands that the destruction be rapid, since in this Way a greatly-increased amount of effective work can be accomplished in a given time. Our present invention affords the first method that is adapted to the use of a lining containing ores carrying sullids of the base metals in combination with silica.

For the reasons above stated all past experimenters have been forced to compound their lining material with alumina or some equivalent bonding agent mixed with water, and where ores were used at all as lining material only such were used as contained high percentages of silica and such as contained no metals other than gold or silver, (preferably in a finely-disseminated state.) Ores which contained base metals, sullids, arsenids, antimonids, or any of the elements or compounds usually found in ores or such process-it has been found necessary either to add additional matte in the molten state from time to time or else to combine charges of matte by transferring partially-blown charges from one converter into another as a means of securing sufficient material with which to finish a charge to blister copper.

1n the Bingham Canon district in Utah many vast bodies of low-grade sulfid ores are found ordinarily containing mineral values varying from four dollars and fifty cents to five dollars and eighty cents per ton. The proportion of copper amounts to one or 1.5

.per cent. and the remaining values consist usually of gold and to a small extent of silver.- In a single instance ores of this character contained total values of seventeen dollars per ton, the copper varying from one to two per cent. and the remaining values consisting principally of gold and silver. These ores at present are smelted in'the ordinary waterjacketed blast-furnace with coke and with slow smelting as a means of enriching them as much as possible before fusion. The resulting matte after the first fusion in the blast-furnace, containing from eight to ten per cent. of material values, "is transferred to a number of silica-lined converters, and it .causes a rapid destruction of their linings,

owing to the heavy percentage of iron; *A large proportion of worthless slag is produced,- and the proportion of resultant concentrated matte is consequently extremely small. In order to conduct this tedious process on commercial lines, it has been found necessary to transfer these small amounts of concentrated matte from a number of different converters into one in order to produce one full molten bath of, say, forty to fifty per cent. convertereral values to our matte, so that we are enabled either to finish the process or, if desired,

. to bring up the grade of our matte to forty or fifty per cent. of copper, or to even a higher grade, if such is desired. This produces what matte-making elements or compounds.

is commonly called converter-matte without resorting to any of the present wasteful and expensive processes ofconcentration by water or by fire. In prior processes ores have, with the one-exception herein referred to, been unfit for use as lining, for the reason they all contain percentages of basic elements or compounds, and are hence unfit for lining converters on the lines of present practice. The reason that an ore lining for converters has been successful at Aguas 'Calientes, in Mexico, the one exception 'above referred to, is because the very unusual ore there used is' practically free from all basic elements or compounds excepting alumina. In our present invention we can successfully use ores carrying large percentagesof bases and basic sulfids, and the presence of these hitherto objectionable elements and compounds will materially contribute to the speed and to the success of the process and will augment the. mineral values contained in the bath. We

are enabled to add copper, iron, sulfids, gold, silver, and any matte-making elements or compounds by means of our lining, and any and all. copper, gold, and silver thus contributed to the bath-through the medium of our lining will add to the enrichment of our matte.

In practicing our invention we take a converter, such as shown in Figs. 1 and 2, made of thick metalblocks 2 and lined with a compact inner lining 5, of silica or silica bricks. We apply to the interior surface of this lining a body or coating 0 of copper ores containing silica and containing also sulfids of iron, copper, &c., and preferably gold, silver, and We prefer to apply this lining by distributing on the interior of the converter a coating of slag or matte in a liquid condition and then to apply the ore lining to the coated interior and to cause it to adhere thereto, after which it may, if desired, be cemented with another addition of slag or matte. The converter being in a heated condition, we run into it from a smelting-furnace, forehearth, 'or other convenient source a body of molten slag, preferably enough to equal in volume one-half the usual converter charge, or we may use for this purpose some molten matte. We then tip the converter back and forth on its axis, so as to distribute this slag or matte over the interior surface in a sticky layer 6, and we then tip the converter completely to discharge the surplus. The body of ore is then latter back and forth it is tumbled over the layerb and caused to adhere thereto in a layer 0, or, if desired, the ore may be spread over the converter with a shovel or otherwise. A

I20. added to the converter, and by rocking the this setting can be hastened by blowing air 1 the charge'as slag-making material will abthereon from the twyers 3. The ore is thus held to the converter with suflicient security to serve as a lining and to supply the flux to the charge beneath the bath; but, being open and unpacked, the lining acts more readily and causes the converting operation to proceed more quickly than is possible with linings heretofore employed.-

Instead of firstdistributing a layer of molten matte or slag over the converter before applying the lining material we may place such material in the converter and cause it to adhere thereto by pouring upon it a small volume of molten slag or matte.

The lining may be constituted by selecting such ores as contain a suflicient quantity of flux, such as oxids or sulfids, to enable the lining to be cintered in place by the application of external heat from oil-burners or the ike.

Instead of using a converter made of metal blocks, as shown in Figs. 1 and 2, we may employ the converter shown in Figs. 3 and 4, having an exterior water-jacket 4 and an interior compact lining 5,0f silica or silica bricks, within which the layer 0 of ore is applied. We show in all these figures burners 7 for supplying flame by which the ore lining may be cintered in place. These burners may be omitted when the ore-body is cemented to the interior walls by molten matte or slag.

The quantity of ore employed as lining material is selected with reference to the composition of the matte to be treated. It should contain suificient silica to flux all the ore contained in the matte that is delivered into the converter, as well as the additions thereto supplied by the fusing of the matte-making compounds introduced with the ore. The amount of ore is preferably so determined that the entire mass will be consumed in a single blow of the converter. It will be patent to those who are conversant with the art of converting that every substance added to sorb and will carry away with it an appreciable amount of copper and that the more foreign material that is introduced into the slag the greater will be the loss of copper. It then follows that any additions of silicious or of aluminous substances will aggravate such copper losses in exact proportion to the amount of such additions.

There is no known way, either by lire, by water, or by leaching, commercially speaking, whereby the silica contained in sullid ores can be removed from the ore without a corresponding loss of the sulfids themselves. Therefore any method that enables the operator to use the same kind of ore for the converter-lining that is used to produce the matte to be converted must effect an important saving in all of the values that would be stolen by substances used for lining that are derived from other sources than the matte-making ore itself.

In the converting process as conducted by us in a converter having a compact silica lining within which the body of ore is applied the bath will attack the loose lining of ore so much more rapidly than it can attack the compacted silica that the latter will not be quickly destroyed.

We claim The method herein described of converting matte. which consists in applying to a compact silicous converter-wall, a loose lining containing matte-making com pounds and silica in amount suflicient to flux the compounds of the matte to be fiuxed, charging matte into the converter and subjecting the same to a blast of air; substantially as described.

In testimony whereof we have hereunto set our hands.

RALPH BAGGALEY. CHARLES M. ALLEN. Witnesses:

WILLIAM M. KIRKPATRICK, W. D. KYLE.

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