US723500A - Treating copper ores and ores of copper and nickel. - Google Patents

Description

No. 723,500. 7 I PATENTED MAR. 24, 1903. H. G. G. THOFEHRN & B. DE SAINT SEINE.

TREATING COPPER ORES AND ORES OF COPPER AND NICKEL.

APPLIOATION FILED SEPT: e, 1901.

N0 MODEL.

l ff/ 767260 3 1 THE NORRIS Psrzas 00., Pno'roumo" WASHINGTON. n. c.

U ITED STATES PATENT OFFICE.

HERMAN N GEORGES CHRISTIAN THOFEHRN OF PARIS, FRANCE, AND BERNARD DE SAINT SEINE, OF WIDNES, ENGLAND.

TREATING COPPER ORES AND ORES OF COPPER AND NICKEL.

SPECIFICATION formingpart of Letters Patent N 0. 723,500, dated March 24, 1903.

Application filed September 6, 1901. Serial No. 74,583. (No model.)

To all whom, it may concern.-

Be it known that we, HERMANN GEORGES CHRISTIAN THOFEHRN, a'former subject of the German Emperor, but in 1896 having declared my intention to become a citizen of the United States, residing at Paris, France, and BERNARD DE SAINT SEINE, a citizen of the French Republic, residing at Widnes, Lancaster county, England, have invented certain new and useful Improvements in the Treatment of Copper Ores and Ores of Oopper and Nickel, of which the following is a specification.

Ourinvention relates toimportantimprovements in the treatment of copper ores and ores of copper and nickel after theyhave been freed by a previous smelting of-their gangue, and it also relates to the treatment and refining of raw and black copper.

Our process consists, essentially, in blow; ing simultaneously and on the same spot of the surface of the metallic bath in a reverbatory furnace an oxidizing and scorifying mix ture composed of superheated steam, air,

silica,an iocc as ip n allyli nichlorin and sea--- salt. We insure thus a very rapid oxidation and a simultaneous scorification Within the zone of influence dominated by the blastpipes of the matters to be eliminated, which can then be rejected from the zone of action of the blast-pipes by the mechanical effect of their blast itself. By this'means the blast acts constantly and directly on a surface of the molten bath, which is continuously renewed.

We have illustrated in the accompanying drawings a reverbatory furnace by means of which our process may be carried out.

Figure 1 is a partial cross-section of said reverbatory furnace, and Fig. 2 is a partial side elevation of same.

The furnace is provided on each lateral side with an opening or door through which the blast-pipes a are introduced. These blastpipes are slanted withrelation to the surface of the bath, and their free ends lead to a slight distance above said surface. I The blast-pipes are mounted on a hollow support I), through which steam is fed and which is movable on bearings 0, so as to allow of parallel adjustment of said blast-pipes. The

steam iscOnVeyed through a piped, connected to the hollow support I) by means of a hose 6. From said support the steam is admitted into the molten bath through the central tubesf, surrounded by the pipes a. The silica is furnished by the sand of a sand box or tank 9, connected to the blast-pipe by a tube h, which is adapted to slide on a joint-piece 't' for the purpose of adjustment of said blastpipe. The air is admitted between the central tubefand the pipe a through small openings m. Finally, valves 01. and 0 allow of mg ulating, respectively, the quantities of steam and silica admitted into the furnace.

We will now describe the application of our process to the treatment of coppernQres mait tesf In the treatment of copper ores and mattes the ore is first melted in a cupola or blast furnace, and the matte produced is charged in a molten condition into our reverberatory furnaceT mixture of air, steam, and silica is then blown on the surface of the molten bath. The quantity of silica is regulated according to the rapidity of the reaction proand m mtra rrqpr and ligand duced and to the composition of the lining of the furnace. If said lining is acid, as usual, the quantity of silica is regulated in order to obtain an acid slag; but if the liningis basic (dolomite, &c.) the quantity of silicais kept low enough to obtain a well fluid basic slag.

The simultaneous reaction of the oxygen of the blast on the iron and of the silica on the peroxid of iron formed not only protects the walls and bottom of the furnace, but also produces enough heat in the metallic bath, so that a small quantity of fuel is sufficient to maintain the temperature of the furnace. The slag produced during this stage of the work is withdrawn by tapping or by skimming, consequently lowering the level of the bath. Instead of working on with a constantly-decreasing level we generally prefer to maintain it at the same height by feeding the bath with fresh ore or matte or preferably with already molten matte flowing from,

a cupola or blast furnace until the Whole of the bath is almost entirely deprived of iron previously contained in it and brought to the state of white metal. When the bath is thus arrived to the state of white metal, we only blow in a small quantity of silica by the blast of superheated steam and air just suflicient to scorify the small remaining quantity of iron and to maintain a thin coating of slag on the surface of the molten bath outside the active zone. We keep on blowing, so as to burn the sulfur which escapes as sulfurous acid until only metallic copper remains. If the matte contains an appreciable proportion of precious metals, such as gold, we withdraw by the ladle or by tapping the first eighth to a tenth of copper reduced from the white metal, which quantity contains almost the total quantity of the gold previously contained in the matte. \Vhile blowing on the white metal, we have noted that the antimony and arsenic contained in the matte are eliminated almost entirely, probably on account of their combination with the hydrogen of the steam. However, if the proportion. of these metals is too large, we add to the blast a little chlorin or sea-salt, which transforms them into volatile chlorids.

In the treatment and refining of raw and black copper we proceed in the same manner as described above in order to eliminate the impurities. We add, however, toward the end of the operation a little lime to the silica in order to maintain a good clear slag. When the copperis suflicien tly cleaned and oxidized, we reduce and we pole it, as usual.

In the treatment of copper and nickel ores we operate in the same manner as above, by smelting first in a cupola or blast furnace, so

as to obtain a copper-nickel matte, then by tapping said matte into a reverberatory fur- V nace, in which it is treated by the blast of superheated steam, air, and silica, carrying along with it a small proportion of lime, until the iron is eliminated. We thus obtain a sulfid of copper and nickel, which is treated as usual.

Having now particularly described and ascertained the nature of our said invention and in what manner the same is to be performed, we declare that what we claim is= 1. A treatment of copper ore, matte of copper and raw copper in a reverberatory furnace, consisting in blowing "into said furnace, on the surface of the bath, a mixture of superheated steam and air carrying along silica,

substantially as and for the purpose set forth.

2. A treatment of copper ore, matte of copper and raw copper in a reverberatory furnace, consisting in blowing into said furnace, on the surface of the bath, a mixture of-superheated steam and air carrying along silica and lime, substantially as and for the pur pose set forth.

In witness whereof we have hereunto set our hands in presenceof two witnesses.

HERMANN GEORGES CHRISTIAN THOFEIIRN. BERNARD DE SAINT SEINE. Witnesses as to H. G. C. Thofehrn:

EDWARD P. MAoLEAN, ANTOINE LAVOIX. Witnesses as to B. de St. Seine:

WM. PIERCE, H. WATSON.

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