US1729408A - Smelting furnace and method of smelting - Google Patents

Description

Sept. 24, 1929.

R.- A. WAGSTAFF SMELTING FURNACE AND METHOD OF SMELTING Filed June 27, 1925 awuen coz MOL y;

Patented Sept. 24, 1929 UNITED STATES PATENT OFFICE RICHARD A. WAGSTAFF, F SALT LAKE CITY UTAH, ASSIGNOR T0 AMERICAN SMELT- ING AND EEFINING COMPANY, OF NEW YORK, 11'. Y., A CORPORATION OF NEW JERSEY SMELTING- FURNACE AND METHOD OF SMEL'IING Application filed June 27, 1925. Serial No. 39,894.

This invention relates especially to smelting processes and furnaces of the reverberatory type adapted for the treatment of copper, zinc or other ores, etc. and the invention relates especially to the type of smelting furnace in which the melt flows from the firing or smelting chamber away from the stack and preferably in the opposite direction to the movement of the flue gases so that the melt flows into a separate or distinct settling chamber where it may be heated or otherwise treated to the desired extent and where the settling and separation of the matte and slag can take place under ideal conditions and in a very advantageous way. It is also advantageous to provide in the smelting chamber a water jacketed or other suitable bridge wall which may more or less surround the charge except toward the burners or firing means and the charge may be advantageously supported on a shelf of refractory lump material such as chrome ore or the like which materially minimizes furnace replacements.

In the accompanying drawing showing in a somewhat diagrammatic way an illustrative embodiment of this invention,

Fig. 1 is a longitudinal section; and Fig. 2 is a top view of the illustrative furv nace.

furnace maybe formed with a roof preferably though not necessarily ofthe arched type which for high smelting heats is preferably constructed of silica brick, and this roof may be provided with a series of feed hoppers such as 18 and co-operating feed passages 20 more or less extending through the water cooled or other feed plate 19 supported so as to extend transversely across the smelting chamber. In this way the charge 10 may be continuously or intermittently fed into the smelting chamber preferably within the more or less enclosing bridge walls 14, which may be of the ordinary water jacket construction; and it is desirable in many cases to provide adjacent the bridge wall a refractory backing 12 formed ofsilica or chrome=brick which are desirable for this purpose, so as to form a more on less inclined support preventing undesirable accumula- The firing or smeltingchamber .1 of the tion of the charge. The charge may be advantageously supported on a shelf such as 9 of refractory lump material such as chrome ore or the like which may of course be fired into the furnace in connection with more or less fiuxed material. This shelf as indicated may extend between the masonry foundation 11 of the bridge wall 14 and the foot wall 7 towardthe tapping end of the furnace, the shelf being of course supported on the furnace bed 38 of any suitable material.

This smelting chamber may be heated in I any suitable way as by a series of oil or powdered coal burners 22 which mayapproach through firing openings 29 extending more or less across the suspended bridge wall of the furnace, and in this way the heat may be directed toward the inclined smelting face of the charge which may be heated to the desired degree and subjected to the desired,

flametreatment at the same time. The hot gases passing over the charge move in the direction of the arrows 36 into the stack chamber or flue 17 so that the flue dust 15 is more or less deposited against the bridge wall 14 for instance. This stack flue may have one or more waste heat boile s 32 of any desired construction on one or both sides of the longitudinal partitions such as 31, 39 shown diagrammatically in Fig. 2.

The separate settling chamber 2 of any desired shape and construction is arranged at the tapping side of the furnace so as to be if desired on the opposite side of the smelting charge from the flue or stack and to preferably have a low arch or small area connec tion withthe smelting chamber;and a suitable hearth 4 may be provided beneath this Iiettling chamber which may as indicated in Rig. 2 have a somewhat elongated shapeiso as to extend to the tappin end or wall 40 of t e furnace which may e formed with a slag hole 24 and matte tapping hole 25 having the usual tapping plugs 26. One or more 7 auxiliary burner or inspectionapertures may be formed in this settling chamber and adjacent parts of the furnace such, for example,

\. one or more burner apertures 23 in the tapjfping wall 40 and smelting burner apertures '35 in the cross wall 41 of the furnace, also tamination of the flue dust and fresh charge so as to promote settling of the matte-below the line-27 and in. this .way considerable reduction in the copper loss in the slagis possible with this furnace and smelting method. This is of course effected most advantageous- 1y when the melt is withdrawn from the smelting chamber in the opposite direction from the movement of the burner flames and flue gases so as to give in a way a countercurrent operation of the furnace; and this makes possible savings in the fuel consumption as well as giving a large recovery of waste heat inthe boilers which may be in the stack flueas indicated; By using a shelf of lump chrome ore construction to support the charge destructive action on this part of the furnace lining is considerably mmmnzed and of course the melt bybeing withdrawn from the intensely hot firing zone or chamber of-the furnace can be maintained at any desired heat, and in many cases where ial heat treatment is umiecessar relae /t1vely lower heats may be used in this part of the furnace so as to correspondingly reduce corrosive action by the slag and resultmg mamtenancechar es.

This invention has described in connection with an illustrative form of furnace and smeltin process, to the details of which disclosure the invention is of course not to belimited, since whatisclaimed as new and what is desired to be secured b Letters Patcut is set \forth' in the appende claims:

1. A smelting furnace comprising a stack flue and a communicating smelting chamber having a refractory charge shelf formed of fired lumps of chrome ore, a transverse series of burners directed: into said smelting chamr' wall adjacent said shelf and having a re-' fractoriy backing to support the charge being smelte a transverse series of feeding means adapted to continuously feed said charge to said shelf and a relatively narrow low arch settling chamber communicating with said smelting chamber and. on the opposite side thereof from said stack flue to wlthdraw the minimlm contammation by the ch'argeand flue dust. v

3. ,A reverberatory smelting furnace comprising a .stack flue and communicating smelting chamber having an arch roof and a charge shelf formed of fired lumps of "chrome ore, atransverseseries of burners edirected intosaid smelting chamber toward said stack flue, a water cooled bridge wall extending across the flue side of saidshelf and having a refractory backing to support the charge being smelted, a transverse series. of feed, hoppers and channels adapted to continuously feedsaid charge and a settlingv chamber communicating with said smelting chamber and on the opposite]. side thereof from said stack flue to withdraw the melt from the smelting charge'for settling with minimum contamination by the charge and fluedust. I M- g 4. 'A reverberatory smelting furnace comprising a stack flue and communicating smelting chamber 'havin a charge shelf formed of fired lumps of c rome ore, a trans:

verse series .of burners directed into' said smelting chamber toward said. stack flue,

a bridge Wall extending across the flue side of said-shelf to support Zthe charge being smelted, a transverse series of feed hoppers and channels adapted to feed said charge and a settling chamber communicating with said smelting chamber and on the opposite side thereof from said stack flue to withdraw the melt from the smelting charge for settling with minimum contamination by the charge and flue dust. i -5. A! smelting furnace comprising a stack flue anda communicating smelting chamber having a refractory; chrome charge shelf and a bridge wall adjacent one end of said jshelf, a series of burners directed. toward her toward saldst-ack line, a cooled bridge said shelf and bridge wall, "feeding means to feed the charge to said shelf adjacent said bridge wall and a settling chamber communieating with saidsmelting chamber and located out of the path of the flue gases from saidburners topromote settling of the melt and minimize heat losses.

g In testimony whereof I have hereunto set I my hand, a g RICHARD A. WAGSTAFF.

charge shelf, a transverse

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