US470384A - Pierre manhes - Google Patents

Description

' UNTTED STATES ATENT Trice,

PIERRE MANI IES, OF LYONS, FRANCE.

PROCESS OF TREATING COPPER MATTE.

SPECIFICATION forming part of Letters Patent NO. 470,384, dated March 8, 1892. Application filed April 27, 1883. Serial No. 98,228. (No specimens.) Patented in France March 26, 1880, No. 124,124.

To all whom it may concern.-

Be it known that I, PIERRE MANHES, of the city of Lyons, in the Republic of France, have invented a new Process of Treating Copper Matte and other Cupreous Matters for Obtaining Metallic Copper, (for which I have re ceived Letters Patent in France, No. 124,124,, dated March 26, 1880,) of which the following is a specification.

Taken, as example, the treatment of sulphuret copper ores, an operation is as follows: Without any preparatory roasting being necessary the ore is submitted to a simple crude melting, which may be executed in a meltingfurnace of any kind, but preferably in a eupola-furnace. This melting has for its object to eliminate the earthy gangues by the formation of a slag and to concentrate the metallic portions into a matte more or less rich in copper always ferreous and highly sulphureted. The liquid matte is taken direct from the melting-furnace to the converter, which has been previously heated to a sufficient temperature. This converter is provided with lateral tuyeres at some distance above the bottom. In passing through the molten matte in the converter the air-blast quickly produces a great elevation of temperature by reason of the combustion first of the sulphur, then of the iron, and the other metals more oxidizable than copper. The sulphur is eliminated by a violent disengagement of sulphureous acid, and it is the same with the other volatile substances, arsenic, antimony, (be. The iron rapidlyburned' and oxidized is transformed into a silicate by the contact with the earthy matters, which form the lining of the converter unless silicious fluxes are introduced, and there results from it scoria, which rises to the surface of the molten metal and which is removed by the ordinary means. The operation lasts but a very short time and the product is rough copper, which only requires to be subjected to the ordinary refining process. It is ascertained when the operation is completed when the sulphurous vapors have almost entirely disappeared and when a sample taken from the converter shows that the rough copperis sufficiently purified to be refined without difficulty. After having removed the scoria the rough copper is poured either into molds or patents granted to me, as showing the pro gress of my improvements in the treatment of copper matte, and as showing features of my invention which have led to the present improvement Letters Patent of France, No. 135,792, deposited March 26, 1880, and additions to the same, deposited May 31, 1880, October 23, 1880, and February 9, 1882; Austria- I-Iungary, No. 7,005 and No. 39,787, dated No. vember 5, 1881, and No. 37,465 and No. 48,602, dated January 4, 1882; Spain, No. 1,135, dated August 31, 1880; German Empire, No. 15,562, dated October 25, 1881, and Great Britain, No. 3,181, dated August 3, 1880.

My invention relates to the treatment of copper matte to produce directly in a single operation, rapid and almost costless, the tran sformation of this matte into rough metallic copper. My process has not, then; for its object to produce the matte itself, and it should be well understood that I reserve to myself the right to employ for the production of the cuprcous matte any system of smelting actually in use for the treatment of ores.

I have said in the preceding description that the operation which is the subject of my invention may be performed in any appropriate furnace orapparatus whatever, but by preference in the Bessemer converter having lateral tuyeres above the bottom. This apparatus is in effect that in which the operation proceeds the best and in which it is made with the most facility. The scoria of the converter being always very rich in oxide of iron may be employed advantageously as dues in the fusion of ores and other material of quartzose character.

Another advantage of my process is to be enabled to obtain copper of very good quality,

too

even from material which by ordinary processes give but veryinferior copper as, for example, gray coppers or arsenious or antimonious matte. The very high heat and the very energetic oxidizing action produced in the converter are eminently favorable to the elimination of arsenicand antimony. When mattes containingalarge quantity of iron are treated, the scoria produced will have a very energetic corrosive action on the earthy lining of the converter, which would thus be so rapidly destroyed that serious accidents might result from it. It is Well, then, in this case to make the interior lining of the converter of a basic matter as lime or magnesia; but then there should be added to the matte in the converter a suitable proportion of a silicious flux which may scorify the oxides produced.

Although, as has been already stated, the operation which constitutes my process is complete when the treatment of the matte is terminated, the converter contains nothing more than rough copper suitable to be refined by ordinary processes. Experience has taught me that the operation may be continued further, and that there may be thus obtained not only rough copper, but also refined copper malleable like the product of the ordinary refinery. I may, then, bya single rapid and inexpensive operation obtain the transformation of the cupreous matte into refined copper ready to be wrought, rolled, or hammered. v

For the above purpose I operate as follows: hen the operation described arrives at its last period-that is to say, when the cupreous matte is transformed into rough copperthe converter is inclined, the supernatant scoria are poured off from the metal or removed by a rabble, and when the surface of the copper is uncovered a sample is taken by a small ladle and broken to examine by its fracture its chemical composition. If the fracture be purple-red and of large grain, indicating that the copper contains a certain portion of protoxide, one may be certain of the complete elimination of foreign matters, and itonly remains to proceed to the reduction of the protoxide, as will be hereinafter explained. If, on the contrary, the metal does not present the indications of pure copper, it must be submitted to a further oxidation to bring it to the desired degree of purity. For that the blast of air is again turned onto the converter, which is returned to the Vertical position. The progress of the oxidation is tested by taking samples, and a few minutes suffice to deprive the copper of its last impurities.

It may happen that the last foreign matters remaining to be eliminated may not be of such nature that they will feed the-intermolecular combustion, without which the copper congeals immediately on the contact of the blast. To prevent that, I introduce into the converter a small quantity of sulphur in powder, causing it to enter with the blast.

This sulphur burning in the mass of metal suffices to maintain the necessary heat. It is eliminated in the state of a sulphurous acid and does not impede, sensibly, the oxida tion of the other metallic substances, the oxygen of the air being always in great excess. I have tried, also, the employment of charcoal powder to sustain the combustion, and

that gives good results; but the sulphur is to' be preferred because of the reductive action which carbon always produces. The copper being sufficiently purified, nothing remains to be done but to give it malleability by reducing the protoxide with which it is impregnated. For that, after having again skimmed it,I throw into the mouth of the converter several shovelfuls of wood-charcoal in small pieces to cover the metal, and then introduce by the blast into the converter powdered wood charcoal in sufficient quantity. This charcoal not only exercises an energetic reductive action; but it serves, also, to elevate consid erably the temperature, which is necessary, in order that the copper may maintain sufficient heat to the end of the running out. During the course of this reduction samples are taken. \Vhen the reduction is notably advanced. and without being yet malleable, the copper commences to take a closer grain and a paler color, the converter is returned to the horizontal position, the blast is stopped, and then the refining is finished as in an ordinary furnace by means of a pole of green wood. This last operation is not long and the copper easily maintains its heat during the necessary time. When the copper is completely refined, the converter is inclined to pour it out either directly into the ingot-molds or into ladles or other receptacles, from which it is afterward distributed to the ingot-molds.

I am aware that copper ore and fuel have been introduced into a furnace similar to a blast-furnace in which it has been sought to,

melt the copper and allow it to run down upon the hearth. In this operation the ore is not submitted to the melting or preliminary preparation necessary to convert the sulphurets of copper into matte.

My improved process is adapted to the treatment of melted copper matte, because all sulphurets require to be converted into the matte before they can be treated by any process.

Iam aware that converters of various kinds have been made use of in which a blast of air, either hot or cold, has been forced up through melted iron for the purpose of burning out impurities and reducing the amount of carbon in the iron, and that in these converters the air-inlet pipes or tuyeres have been introduced vertically through the bottom and also horizontally at or near the bottom.

I am also aware that efforts have been made to separate from copper ore or matte impurities by the action of a blast of air in a converter similar to that known as the Bessemer converter, with tuyeres passing in at the bottom.

In all the efforts heretofore put forth to separate foreign substances from copper matte the mode of operation pursued has been similar to that employed in treating iron-namely,

to force the atmosphere through the entire mass, including both the matte and copper, as it is separated from the matte. In practice it was found that the copper became chilled and the desired object was defeated. Eiforts were then made to remedy this diificulty by the use of a hot blast, but without success.

I have discovered that the mode of operation required in the treatment of copper is radically different from that in the treatment of cast-iron, and that'in the treatment of copper matte for the production of metallic copper it is necessary to prevent the atmosphere acting on the metallic copper as much as possible and to confine the action of the atmosphere to the matte which contains the impurities. Thereby I able to consume and volatilize the impurities and to melt and separate the copper and prevent the atmosphere chilling or oxidizing the same. In cast-iron there is a large proportion of iron, about ninety-five per cent. or more, and a very small amount of impurities, about five per cent. and less. Throughout the entire process of converting cast-iron by forcing air through the molten mass it remains homogeneous, and the oxidation of the carbon and other impurities furnishes sufficient heat to keep the iron melted and the blast is necessarily made to penetrate every portion of the liquid metal. As the impurities amount to less than five per cent. of the original weight of the crude iron, its volume is not essentially diminished by the converting process, and the height of the melted iron in the converter remains nearly the same at the conclusion of the process that it was at its commencement. The conditions in the treatment of copper matte are entirely different. An average copper matte contains, say, fifty per cent. of copper and fifty per cent. of impurities. The object of the present invention is to remove the impurities. As the air is blown into the molten matte the sulphur passes off in the shape of gas and the iron and other metals form a slag which is easily removed from the surface, while the copper as it is set free from its impurities descends drop by drop to the bottom of the converter and below the holes through which the blastenters, so that it remains in a comparatively quiescent condition, forming a metallic bath which supports the remainder of the unconverted matte, and which is still subjected to the action of the blast. The point essential to the success of the process, and which has hitherto been entirely overlooked, is that as soon as the metallic copper is formed it must be allowed to subside below the action of the blast, and thus separate into two layers, a lower one of copper and an upper one of matte, the lower one increasing and the upper one diminishing as the process advances, until finally almost all the matte is changed into metallic copper and has subsided below the level of the blast.

I am aware that copperhas been treated in a Bessemer converter, and that illuminatinggas has been blown into the same for the reduction of any oxide of copper., I am also aware that copper matte has been treated in a double converter with aconnecting-passage having air-inlet tuyeres at various heights.

It is to be understood that the amount of the charge introduced into the converter will depend upon the proportion of copper contained in the matte and the height of the tuyeres from the bottom of the converter. For instance, if the matte contains thirty per cent. of copper and the treatment in the con verter results in copperwith five per cent. impurities, the volume of the matte introduced into the converter will be about three times the contents of such converter below the tuyeres. The workman has also to allow for the increase of size in the bottom of the converter by the lining being melted from time to time and combining with the slag.

I am aware that in Patent No. 184,988 to E. E. Sluder the ore was subjected to a melting operation and that the copper sunk intoa bath below the slag and below the tuyeres. In this case the ore is reduced and the metal separated to a certain extent, the same as in any ordinary cupola. No provision is made for the removal of impurities from the copper itself. In my process the bulk of the impurities in the ore is removed in the smelting operation, and the converter is used only for a second operation-viz., the removal of impurities from the copper in the condition of melted matte.

I am also aware that in the English Patent No. 4,549, of 1878, of Holloway, is set forth the addition of sulphides to a bath of molten sulphites to promote the heat, and these operations are proposed to be done in a converter; but in consequence of the bulk of the slag and ore and the difficulty of separating the same from the copper while exposed to the action of the blast this plan has not been practically and commercially employed. By supplying the melted matte into the converter and sub jeeting the same to the action of air -blasts blown in above the bottom on which the copper accumulates the charge can be finished by burning out the desired proportion of impurities from the copper, and the operation can be performed with the rapidity and facility necessary to make it a commercial success.

I am also aware that in English Patent to Tessie du Motay, No. 1,750, of 1870, silica is set forth as added to a charge of copper matte.

I claim as my invention- 1. The process of reducing commercial or metallic copper from copper ore, consisting in smelting the ore by the aid of extraneous fuel and producing copper matte, charging the matte in a molten condition into a converter, forcing jets of air through the molten matte and maintaining it in a molten condition and at the proper temperature by the heat generated by the combustion of the sulphur and non in the matte, continuing the operation until the sulphur and iron have been separated from the metallic copper, and allowing the latter to settle below action of the airjets, substantially as set forth.

2. The process of reducing commercial or pig-copper from copper matte, consisting in charging the matte in amolten condition into a converter, forcing jets of air through the molten matte and maintaining it in a molten state and at the proper temperature by the heat produced by the combustion of the sulphur and iron in the matte, and continuing the operation until the sulphur and iron have been separated from the metallic copper and the latter has settled below the action of the air-jets, substantially as set forth.

The process of reducing commercial or pig-copper from copper matte, consisting in charging the matte in a molten state into a converter, forcing jets of air uniformly throughout the charge of molten matte, and

causing the heat produced by the combustion of the sulphur and iron in the matte to separate the sulphur and iron from the metallic copper and allowing the latter as it is sepav ally and allowing the copper to subside into the portion of the converter below the airblasts, substantially as specified.

In testimony whereof I have signed this specification in the presence of tWo subscrib ing Witnesses.

PIERRE MANIIES.

Witnesses:

LoUIs BAOHELER, J. P. A. MARTIN.

impurities by blasts of air introduced later-