US806045A - Method of converting matte. - Google Patents

Description

PATENTED NOV.'28, 1905. R. BAGGALBY & 0. M. ALLEN.

D 0F GONVRTING MA LEDIJULYls. 1904. BENBWED TTB.

METHO APPLICATION r1 10.806,045. PATENTED NOV. 2a, 1905.

R. BAGGALEY & c. M. ALLEN. METHOD of' GONVERTING MATTE.

APPLICATION FILED JULY 18, 1904. RENEWED APR. 6. 1905.

s sHEETs-si1EBT 2.

PATENTBD Nov. 28 ALLEN.

R.v BAGGALBY E o. METHOD 0T GONVBRTITM.v MATTE JULY 1a APPLICATION FILED RENEWED APR..

3 SHEETS-SHEET 3.

wn'nlssssV `IINITED STATES PATENT oEEIoE.

RALPH BAGGALEY, oE PITTSBUHG, PENNSYLVANIA, AND` CHARLES M. ALLEN, oE LoLo, MONTANA; SAID ALLEN ASSIGNoE To SAID BAGGALEY.

lvlETHoD oF ooNvEnTlNG MATTE.

- Specicaton of Letters Patent.

Patented Nov. 28, 1905.

Application led July 18, 1904. Renewed April 6, 1905. Serial No. 254.112.

To all whom it may concer-n:

Be it known `that we, RALPH BAGGALEY, ofv

the city of Pittsburg, in the county of Allegheny and State of Pennsylvania,and CHARLES M. ALLEN, of Lolo, in the county of MissoulaJ 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 had to the accomverter suitable for the practice of a modifica.-

tion of our invention wherein the ores are attached to the converter by partial fusion. Fig. 4 is a vertical cross-section on the line -IV 1V of Fig. 3. Fig. 5 is a vertical longitudinal section of a water-jacketed converter for practicing a modification of our invention. Fig. 6 is a vertical cross-section on the lines VI VI of Fig. 5.

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 into a source of profit, thus constituting a l new method of converting mattes.

In the practice of our invention th ree things are of importance: iirst, that the converter-` ,cannot be destroyed during 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-wallsmay 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 such4 .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 low-grade matte; third, that the converter may be able to withstand this exacting service without unduly abstracting and dissipating the internal heat that;is gen- Fig. 2 is a vertical erated by and that is essential to the success of the process.

The apparatus which We prefer to use in vpracticing 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 application, Serial No. 200,943, iiled March 31, 1904, and which is lined, preferably, with magnesite brick, as shown in Figs. 3 and 4. Another good form of apparatus is that shown in Figs. l and 2. The water-jacketed converter shown vin Figs. 5 and 6 can be use'd -in practicing this art; but we recommend that at the later stages of the process the iiow of water through the jackets be greatly. reduced or preferably shut ,Y olf altogether for a time in order to prevent In John Holways Patent No. 234,129, dated' November 9, 1880, a Iprocess is described wherein silicious and slag-producing materials are added to the matte. Metalliferous substances containing the necessary slag-producing materials and containing also valuable metals in such small quantities as to make them unfit for treatment by themselvesare described as preferable.

In actual work John Holway reported to the London Society of Arts that 'he used quartz-sand impregnated with about live per cent. of oxid of iron. He fed this with a shovel into the converters mouth, but without success. y

Attempts have been made to supply silica o r silicious ore in pulverized form by injecting it with the blast into the molten bath; but this process has not been successful.

It has also been proposed to utilize ore that contained not le neighty-iive per cent. of silica and whov istinctive feature was silver values, `andtoea li'ton of pulverized argentiferous quartzto add one hundred and IOO p the molten bath.

proportions of water to make a plastic lining for the converter to flux the oxidized iron of This process has also remained to the present day unused.

At Aguas Calientes a very unusual ore obtained from the St. Gertrude mine, in Pachuca, Mexico, has been utilized asa successful converter-lining and fiuxing 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 lininginto very large converter-shells, usually to a thickness of about twenty-four inches.

It has also been proposed, though without success, to feed white-hot silica into the mouth of the converter.

In the process described in a patent of Ralph Baggaley, No. 746,241, dated December 8, 1903, cold silica in solid form was fed into the converter either on top of a clean body of molten converter-matte or preferably into an empty heated converter, where it was agglutinated by auxiliary heat, and thereafter the body of molten converter matte was poured into the converter upon it.

Ralph Baggaleys Patent No. 7 46,260, 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 converter-linings 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 effect of decreasing the volume 0f 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 except-ion 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 Vhand-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 inasmuchas 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 thc 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 seme places than it does at others. 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. When 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 that it 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. Itis estimated that each converterlining 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 a measure of economy. rThis 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 sacrlficed in the effort to maintain the life of the lining to the utmost. By our invention this practice is entirely reversed, and 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 greatlyincreased amount of effective work can be accomplished in a given time.

Our present invention alfords the first method that is adapted to the use of a lining containing ores carrying suliids of the base metals in combination with silica.

For the reasons above stated all past experimenters have been forced to compound IOO 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 con tained no metals other` ythan gold or silver, (preferably in a finely-disseminatedstate.) Ores which contained-base metals-sulfide, arsenids, antimonids, or any of the elements or compounds usually found in ores-or such as Would readily be dissolved, and indeed all ores which` contained matte-making elements or compounds were avoided.

In present practice, where mattes are low grade in copper values-say below forty per cent., inasmuch as practically the entireremaining sixty per cent. constituting a much larger proportion of the total bulk of the charge, lnust be removed in the converting process-it has been foundnecessary either to addk 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.

. In the Bingham Caon district in Utah l many vast bodies of low-grade suld ore's are sisting principally of gold and silver.

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 oresl of this character contained total values of seventeen dollars per ton, the copper varying from one to -two per cent. and the remaining values conl y These ores at present are smelted in the ordinary water-jacketed blast-furnace with coke and with slow smelting as a tmeans of enriching them as much as possible before converting. The resulting matte after the first fusion in the blast-furnace, containing from eightzto ten per cent. of mineral 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 slagl'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 brought up to the grade of blister-copper in 4 a single silica-lined converter.

vBy our present invention We depart widely from prior practice, because We utilize as a` iiuxing agent ores that carry varying perduces what is commonly called convertermatte without resorting to any of the present wasteful and expensive processes of concentration by water or by tire. Inprior processes ores have with the one exception herein referred to been unfit for u se 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 thatv 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 kbasic elements or compounds excepting alumina. In our present invention we can successfully use ores carrying large percentages Vof bases and basic `suliids, and the presience of these hitherto-objectionable elements,

and com .pounds'will materially contribute to the speed and to the success of the process vandwill 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 Ato the enrichment of our matte.

Our present invention in intent and effect is t-he reverse of all prior efforts to convert mattes, as it offers the only instance wherein it is possible to operate economically with a converter wherein the lining material is entirely consumed in one converting operation and also wherein the converter itself is thereafter in a suitable condition to admit of continuous work without additional expense for renewals or for repairs.

In the metallurgy of copper a greater necessity 'exists for exact weights and exact pro- IOO IIO

tions, for instance, of silica, lime, iron, sulfur, &c., should be exact by weight and that guesswork should not be relied on for these things. It is useless to predetermine proportions by assay if such proportions are not subsequently delivered. If they be not delivered, exact work is impossible.

' Our present invention affords the only instance in themetallurgy of copper where one can calculate in 'advance the exact amount'of acid or of base that will be dissolved and that will beactually received into the molten bath to produce expected results, inasmuch as we dissolve it all. In all past processes the quantity or proportion of silica that is dissolved from the converter-lining must necessarily be an unknown quantity, for no one can tell in advance how much or how little of it will be dissolved. For this reason our present invention affords a scientific method where actual figures based on the chemical equivalents of the elements contained in the ore or silica lining can be arrived at.

In the practice of our invention we prefer-- ably take a converter-such, for example, as shown in Figs. l and 2, which is made of thick metal blocks 2 and which may be provided with a magnesite-brck interior liningand apply to its interiora body or coating of copper ores containing silica and containing also sulfids of iron, copper, &c., and preferably gold, silver, and matte-making elements or compounds. 7e prefer to apply lthis lining by distributing on the interior of the converter a coating of slag or matte in a liquid condition and then to apply the orelining 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-furnaee, 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 rmatte over the interior surface in a sticky layer as shown in Figs. l and 2, and we then ltip the converter completely to discharge the surplus. rlhe body of ore is then added to the converter, and by rocking the latter back and forth it is tumbled over the layer and caused to adhere thereto in a layer c, or, if desired, the ore may be spread over the converter with a shovel or otherwise. A small quantity of molten matte or slag is then preferably poured into the converter and being distributed in like manner over the ore or silica lining completes the bonding of the particles. The slag or matte quickly sets.l and, if desired, this setting can be hastened by blowing air thereon from the twyers 3. The ore is thus held to the converter with suiiicient security to serve as a lining and to supply the flux to the charge beneath the bath; but beingopen 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 first distributinga 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 sufiieient quantity of flux, such as oxids or sullids, to enable the lining to be cintered in place by the application of external heat from oil-burners or the like.

Instead of using a converter made of metal blocks, as shown in Figs. 1 and 2, we may em- -ploy the converter shown in Figs. 5 and 6, having an exterior v:iter-jacket et and an interior liningl 5 of magnesite, within which the lining c of ore is applied. We may also use apparatus such as shown in Figs. 3 and I, in which the converter-shell is constituted of heavy metal blocks 2, h'aving an interior lining 5 of magnesite brick, within which the ore lining c is placed, as above described. We also showin this converter burners for supplying flame by which the orc lining` may be cintered in place. These burners may be omitted when the ore body is cemented tothe interior walls by molten matte or slag.

The quantity of ore employed aslining material is selected with reference to the composition of the matte to be treated. It should contain sufficient 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 consulned 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 the charge as slag-making material will absorb 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 lossesv 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 suliids 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 thatwould be stolen by substances used for lining that are derived from other sources than the matte-making ore itself.

While in the foregoing description we have specifically described converter-walls composed of heavy metal blocks, of heavy metal blocks supplemented with an interior basic lining and water-jacketed walls supplemented with an interior basic lining, we do not limit our invention thereto, but intend in our broader claims to claim our new method when practiced 4with apparatus of any kind. 'lhus lOO IIO

' within the scope of ourbroader claims the ore lining above described may be applied to a converter having a compact silica lining providing the ore lining contains approximately suliicient iuX to satisfy the body of matte, after the latter has been supplemented by the additions resulting from the melting of the orelining itself. 4When such is used, the bath will attackl the loose ore lining so much more rapidly than it can attack the oompact silica lining, that successful practice of our invention can be attained.

Doubtless many variations in this process will suggest themselves to those skilled in the art; but,

Having devised, the only method that has ever been used that is adapted to utilize the same kind of ore for lining the converters that is smelted to produce the matte for the converter, we claim 1. The method herein described of converting matte, which consists in subjecting matte to an air-blast in a converter having an uncompacted lining, composed of the same material as the ore to produce the matte to be converted; substantially as described.

2. The method herein described of converting matte, which consists in introducing a body of matte into a converter lined with a body of value-bearing ore loosely held together, and subjecting the matte to an airblast; substantially as described.

3. The method herein described of converting matte, which consists inl introducing a body of matte into a converter lined with a body of value-bearing'ore loosely held together without aluminous bonding material, and subjecting the matte to an air-blast; substantially as described.

4. The method herein described of converting matte, which consists in introducing matte into a converter having a lining containing silica and sulfds of the base metals, as a means of increasing the Volume of -the matte yand liuxing the same, and subjecting the matte to an air-blast; substantially as described.

5. The method herein described of converting matte, which consists in applying to a converter a lining of ore containing mattemaking material, introducing mattethereinto.

and subjecting the same to an air-blast; stantially as described.

6. The method herein described of converting matte, which consists in applying to a converter a lining of ore containing silica and subthe entire body of the lining in the convert-l ing operation; substantially as described.

8. The method herein described of converting matte, which consists in applying to a converter a lining containing ore in a predetermined amount; supplying matte thereto; blowing air thereinto and consuming the entire body of. the lining in the converting operation; substantially as described.

j 9. The method herein described of converting matte, which consists in applying to a nonsilicious converter-wall, a loose body containing matte-making kcompounds and silica and introducing low-grade matte thereto, and subjecting the same to an air-blast; substantially as described.

10. TheA method herein described of converting matte, which consists in applying to a non-silicious converter-wall, a loose lining containing matte-making compounds and silica, in amount suilicient to flux the compounds 'ofthe matte to be uxed; introducinglowgrade matte thereto and consuming said -lining in a single converting operation; substantially as described. V

In testimony whereof we have hereunto set our hands.

RALPH BAGGALEY. CHARLES M. ALLEN. Witnesses: I

WILLIAM M. KIRKIATRICK, FRANK L. RILEY.

. matte-making material; adding thereto a body

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