US805896A - Finishing-converter. - Google Patents

Description

BEST AVAILABLE COP PATENTED NOV. 28, 1905.

C. M. ALLEN. FINISHING GONVERTER. APPLICATION FILED APR.17.1905.

VINVENTQR.

WITNESSES asses B EST AVAILABLE COP I PATENTED Nov. 28, 1905.

0. M. ALLEN. FINISHING CONVERTER.

APPLICATION IILBD APR.17. 1905 2 SHEETS-SHEET 2.

INVENTOR cart-1 24. w!

BEST AVAlLABtE coP UNITED STATES PATENT OFFIOE.

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

FINISHING-CONVERTER.

Specification of Letters Patent.

Patented Nov. 28, 1905.

Application filed April 17, 1905- Serial No. 255,869.

accompanying drawings, forming part of this specification, in wh1ch- Figure 1 shows a crosssection through the center of the converter on the line I I of Fig.

2. Fi 2 shows a longitudinal cross-section 'throug the converter on the line II II of F1 1 1. The object of my invention is more especially for use in practicing the art disclosed in Letters Patent No. 7 66,654, issued on August 2, 1904, to Ralph Baggaley and Charles M. Allen; but my present invention is not limited to the practice of that process stated,

but may be advantageously uti'lizedin .con'

vrting mattes in the manner heretofore univers ally practiced.

I: the drawings, 2 is the converter-shell. 3 is a silica lining, 4 the twyers, and 5 a cradle on which the converter is rotatively su ported, or it may be supported on suitab e trunnions.

6 is a cylinder having a rack 7 meshing wizi a pinion on the converter-shell for rotating it, or other power devices may be sub stituted for this purpose.

'a'he converter has a solid-metal top or l cover 9 of sufficient thickness to withstand the'internal heat without need of a refractory lining. On this top is a heavy reversible metal ring 8 of circular section, so that its position may be changed many times in order thus to present many new wearing or cutting surfaces before the entire ring is destroyed. In order to'make this shifting of the ring possible, the screws and screw-holes are purposely made to register accurately. In this way a sin le ring may be made to outlast many rings 513,15 do not possess these features. Y 4

Those conversant with the art of converting copper mattes are aware that during the working of the converter a certain amount of molten material is thrown up more or less violently by the blast, some of which passes above the extreme limit of the opening in the converter-shell through which the gases escape and through which the slag, matte, and metal are poured. While some of this matinue to build up, one upon the other, until the opening becomes so small that it becomes necessary for the workmen to bar them off in order to again open up an outlet for the gases. l/Vhen the top is lined with a refractory material, each act of barring removes a certain amount of this lining and the concussion tends to shatter the eneral structure, so that such linings can only last a short time, because of these things alone. The dissolving action, too, that takes place through the chemical combination of the linin with the charge during the act of pourin aids its rapid destruction very materially. in the case of my solid-metal-top converter the accretions to be removed are so friable when com ared to the top itself that there is absolutely no destructive action from barring. The weight of the metal to is so proportioned to the molten materia handled that it can never reach the temperature of combination with either the acids or the bases of the charge. Thus any chemical action in-so far as the top is concerned is rendered nil. The result is a solid-metal top that is practically indestructible and which requires no repairs and that is the same in form, quality, and efficiency after months of steady operating. -It is in short the same as it was when work was beun. known top that is used for a like purpose at present.

In the new process of treating ores above referred to a large tonnage is melted and thereafter enriched through the converting process. This requires alarge vessel; but my present invention provides a small converter, preferably lined with silica, excepting the top, in which I receive and finish the molten contents of the large primary c011- verter when the bath has been enriched to the grade of white-metal or about seventy-six per cent. copper, or, in other words, when it has reached the stage where practically all of the iron contents of the matte have been separated and discharged.

This cannot be said of any other 7 The advantages that I obtain by this procedure may be briefly stated as follows:

' First. The bath at this stage is reduced to a small volume. converter which constitutes my invention is a convenient vessel for converting the bath quickly to blister-copper.

Second. By transferring the bath of whitemetal from the large primary converter into my small finishing-converter I practically increase by one-third the producing capacity of the primary converter in a given time.

Third. The walls of the primary converter are referably made either of bare metal bloc ssuch, for instance, as copper, steel, or iron-or metal water jackets or air jackets may be used in whole or in part, or I may supplement the interior wall of the converter with a lining of magnesite or of some other basic refractory material, the purpose being to employ a converter having a nonsilicious interiorthat is to say, either a neutral surface or a basic refractory surface. I have found that such walls are necessary to withstand successfully the corrosive action of the iron while it yet remains in the bath. Any of the walls above described are better conductors of heat than a wall com osed of silica. Hence if the bath be trans erred to my small silica-lined vessel after the iron has been eliminated from the bath the heat may be more successfully retained until the bath has been blown to blister-co er and poured.

Fourth. The vessel is mucii Iighter than the primary converter. Hence it requires less power to o erate it, and it is moreconvenient.

Fifth. en used in the manner stated, the silica-lined vessel becomes practically indestructible, ordinary wear and tear excepted. It is a well-known fact that present converter-linings are destroyed through the corrosive action of the iron in the matte, whereas in this vessel no iron is permitted to come into contact with the silica lining.

Sixth. I have found that when the top or cover of this converter is made of heavy solid metal it is capable of withstanding the internal heat of the converting process indefinitely, so that by this means I am enabled to eliminate the present expense, delay and heavy investment necessary in lining and relining such tops or covers with refractory material. I am thus enabled to accomplish a great reduction over the present cost of converting.

Seventh. By the use of the reversible top ring or lip of this converter I effect a great economy'in operation. [The molten copper is poured over this lip while casting plates, ingots, or bars, and in time this hot bath will have the effect of cutting it out or fire-cracking it on the side where the molten bath passes over it.

It is Well known to those who practice the art of converting mattes that the size of the charge of copper that is to result from the op- Hence the small finishing' eration must be proportionate to the size of the vessel in which the work is done. There must be a sufficient amount of molten matewould amount only to two tons of bath in the converter. It can, therefore, be readily understood from this illustration that it would be practically impossible to complete the'operation under these conditions and in a vessel of such large dimensions. In present practice it is found that where mattes contain. below fifty per cent. of copper (and even then when the vessel has been enlargedby the erosion of the lining through the corrosive action of repeated charges) that as the blowin progresses and as the slag is removed the c arge diminishes in weight and to such an extent 1n bulk, that additions of fresh matte must be made as a means ofv maintaining a proper proportion betweenthe size of the vessel and the contained char e under treatment, so that the work can e completed. It has been found that the best results can only be secured where the amount of material to be removed from the charge is not more than twenty-five per cent. of the original charge, and a careful and intelligent comparison of converting steel with the converting of copper matte will demonstrate that even a lower proportion of the material to be removed to that to be retained to the finish of the converting operation is very desirable. The tendency of all advanced practice in this line is in the direction of larger converters and lower grade matte. Each of these tends to increase the relative amounts of original charge and to lessen the roportionate amount of finished product. or these reasons a finishing-converter which performs the most diflicult and the most sensitive part of the entire work, and which has the chargeto handle when it contains the least heat-producing elements and at a time when the charge reasons described above, but where extremely v low-grade mattes are made, such as those contemplated in the Nprocess described in United States Patent 0. 766,654,, issued August 2, 1904, it becomes of great importance,

and I may say practicall imperative.

It will be apparent to t ose skilled in the art that this same form of converter may be used vention.

BEST AVAILABLECOP] with advantage and economy in converting copper mattes as at present practiced. While for the eculiar special purpose above described 1t is my intention to use the vessel specially as a finishing converter and in small sizes, it may be used in larger sizes without departing from the spirit of my in- I wish to call particular attention to facts that I have ascertained in my smelter work in connection with basic and silica linings. When any of the ordinary basic niaterialssuch, for instance, as magnesite, chrome, &c.are used, they constitute ideal refractories for withstanding the corrosive action of copper mattes up to the grade of white-metal, or, in other Words, up to seventysix per cent. metal, or so long as iron is present in the matte. I have found, however, in my work that these basic linings are good conductors of heat; For this reason in finishing copper mattes from the grade of whitemetal up to blister copper, or, in other words, at a time when the molten bath is extremely sensitive to any chilling action, I have found it difficult and in some cases impossible to finish the charge to blister-copper 1n a'basic-lined converter without providing an auxiliary heatsuch, for instance, as an oil or gas fiamkdu the final stages of the process. Fuel-oil is costly and involves an excessive and an unnecessary expense. I have found that so long as copper mattes are free from iron, or, in other words, when they have reached the grade of white-metal, a silica lining'in a converter becomes practically indestl'uctible, ordinary wear and tear excepted. Nearly ure silica is an excellent non-conductor 0 heat, and it is therefore an ideal lining with which to finish copper metal to blister-copper without the expense of auxiliary heat. This practiceto wit, the treatment of copper mattes up to or near the grade of White-metal in a basic-lined converter, the transfer of the matte at the grade of practically white-metal from a basic-lined converter into a converter lined with silica, in which latter the molten bath is thereafter finished to blister-copper-I claim is broadly new, is not at present practiced, and has never been practiced in the past. This constitutes practically ideal economical converter practice, because each vessel thus becomes practically indestructible. v

Doubtless many modifications will suggest themselves to those skilled in the art, since That I claim is 1. A converter having a refractory lining and a to composed of thick metal of sufficient bulk the converting process; substantially as de: scribed.

2. A converter-top, composed of unlined thick metal of suflicient bulk-to withstand the heat produced by the'converting process; substantially as described.

In testimony whereof I have hereunto set my hand;

CHARLES M. ALLEN.

l Vitnesses:

WVILLIAM M. KIRKPATRICK, AZELLE E. HOBART.

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