US850039A - Ore-roasting apparatus. - Google Patents

Description

010.050,039. A y PATENTED 0130.9, 1007. R. MGKNIGHT.

ORE ROASTING APPARATUS.

APPLIGATIoN FILED 0m10.190s.

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No. 850,039. PATENTRD APR. 9, 1907. R. MGKNIGHT.

ORE ROASTING APPARATUS.

APPLICATION FILED JULYe. 1903.

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WTNESSES A IINVENT.'

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y rrEn salaires ENEENYE Enron YEoEEE'r MeNNrenT, oErH Specification of Letters Patent.

ELrnn/i, PENNSYLVANIA.

oss-acasrme appenni-Ue.

ltatented April 9, 1907.

Application filed July 6, 1903. Serial No. 164,342.

roasting apparatus embodying the hereindescribed lnvention. Fig. 2 is a full section on liney y, Fig. 1. Fig. 3 is a similar section on line z z, Fig'. 1.

This invention is an improvement in apparatus in the nature of a roasting-furnace for use more especially in carrying on processes for the volatilization of precious metals from their ores and the 'recovering of the metal values contained in the `fumes of volatilization-such, for example, as the process described in Letters Patent of the United States issued October 27, 1901, No. 685,691.

The main object of the invention is to provide such an apparatus in which balling or casking'of the ore being treated is obviated or -minimized, and also to completelyl expose the ore to the influence ofthe air in the furnace.

The invention consists in certain devices and combinations hereinafter described and Referring to the accompanying drawings, one ortion of the apparatus consists of a fixe cylindrical structure 1, preferably lined on the inner side with tire-brick 2. Concentric with this structure is a vertical shaft 3, that is journaled in suitable bearings and is adapted to be rotated vfrom a source of power. series ofv obconic cones 4, of suitable material and preferably hollow, as shown.` As a convenient means for securing'these cones to the shaft 3, so as to be rotatable therewith, I make said shaft square in cross-section, (exceptl the part within-the bearings) the holes of the cones being provided with correspondingopenings to receive the shaft, as seen. The said cones are slid upon the shaft, the lower end or hub of each resting upon the top of the next below, and the lowermost cone resting upon the bottom of the cylinder or, rather, inI this instance u on a box or bearing 5 Yof the shaft, whic bearing extends through the fire-brick lining of the bottom of the cylinder.

Fixedly mounted on this shaft is a Secured to and extending from the inner wall of the cylinder are a series of annuli 6,

preferably hollow, as shown, whose upper walls are inclined downwardly and their lower walls or bottoms are substantially horizontal. The-p ose in inclining downwardly the upper was of each of the annuli 6 is to'discharge the gravitating ore at the center of the next lower cone, and thus hold the ore uponthe cones for the greatest period of time. The dimensions of'these annuli are,

as shown in Fig, 1, such as to leave an annu lar passage-way 7 communicating between the bottom of each annulus and the top of the next conebelow and between the sides of the annulus and the side of the cone. There is no annulus below the lowerrnost cone,

which cone is provided on opposite sides near its periphery with 'Scrapers 8, two in the present instanceythat project into an annuar trough 9, that is cut away at one point to an opening 10, Fig. 3, that isabove an outlet pipe or conduit 11 (hereinafter referred to)` The bottom of the upper annulus is pro-A vided with numerous perforations 15, and,

extending through the cylinder at a point above said bottom is a pipe 16 for the escape of the fumes.

Having thus described my invention, I proceed to explain'the mode of operation thereof, as follows: The furnace having been started and the interior of cylinder 1 becoming heated to a required temperature, the shaft 3 is driven at'a suitable speed, thus rotating the cones 4. The pulverized ore orA IOC ore mixture is now fed into the hopper 14 and descending upon the inclined to of the `upper oneof'the annuli is scrape or agitated y the rotating Scrapers 13 and falls upon the top -of the upper one of the cones 4 adjacent to the shaft 3. The rotation of the cone p carries the ore outwardly in a thin layer by the centrifugal force to the periphery of the cone -and it (the ore) then falls down the inoline of the second annulus 6, upon the sec- ICS , successively from cone to cone on to the to. .of

the lowermost cone, from which it falls lnto a circular trough 9 and is carried by the Scrapers 8 to the opening 10, whence it falls into the pipe 11 and' is delivered from the cylinderv 1. During the entire course of the ore or ore mixture it is agitated and s read out and is at the same time subjecte to a roasting process by the heat of thel furnace and the air that enters the open end of the cylinder. In case the amount of this air be insufficient means may be employed for forcing a current of air up through the appar ratus. The fumes formed in the process rise up through the lapertures 15 of the bottom o the upper ann us -and pass @if by way of thei'umei elvtoasuitablecondenser. Usu ally it wil enecessary or desirable to. use a suction device to aid in drawing off the fumes.

As is well known, in roasting ores containing gold and silver and also containing metalloids-such as sulfur, phosphorus, &c.-`-a caking or hailing usually occurs, thus preventing perfect roasting and necessitating regrinding of the balled ore. Silnilar difficulty occurs when ores containing antimony, bismuth, dce., are subjected to a temperature of more than about 300 centigrade. Also ordinarily ores containing the precious metals and lead or antimony cannot be thoroughly roasted with sodium chlorid or other haloids`without balling. With my apparatus, hewever, the ore being agitated and thrown outwardly in a succession of thin layers or bodies by the centrifugal force the heat or hot air entering the vertical vessel or cylinder 1 from the pipe 11 can reach every particle of the ore, and certainmetal or'metalloids that would cause caking or balling are eliminated-that is, the gradual travel or descent of the ore from a low to a high temperature volatilizes the excess of metals and metalloids that cause the diiiiculty before mentioned.

Instead of having the lower end of cylinder 1 communicate with the furnace, and

thus allowing the products of combustion to pass through the apparatus, I may sometimes use a furnace for generating superheated air, which is allowed to enter orl ings.

The Scrapers 13 maysometimes be dispensed with, as also. the Scrapers 8, and the trough 9 andother means substituted for conducting the ore to or causing it to escape linto the pipe 11'.

. Having thus described my invention, I claim as new and desire to secure by Letters Patent- 1. In an ore-roasting ap aratus, the combination with ahollow cy inder, of a vertically-arranged rotatable shaft therein, a series of obconic cones mounted' on said shaft,

a corresponding series of annuli extendingv from the sides of' said cylinder and arranged in the spaces between said cones tov forni a,

continuous passageway between the latter and said annuli, saidcylinder having at its l-us being perforatedv for collecting the fumes rising through the cylinder, and a pi e connected to' said topmost annulus for eading the collected fumes therefrom.

2. In an ore-roasting ap aratus, the combination with a hollow cy fnder, of a vertically-arranged. rotatable shaft therein, a series of obconic cones mounted on said shaft, a corresponding series of annuli'extending from the sides of said cylinder and arranged in the spaces between said cones to form -a continuous passage-way between the latter and said annu-li, said cylinder having at its upper end an inlet for the ore and also at its lower end an exit for the ore, a trough arranged below the edges of the lower cone for receiving the ore from the latter, Scrapers carried by said lower cone for discharging the ore from said trough into the exit in the lower end of the cylinder, the topmost annulus being perforated for collectingthe fumes rising through the cylinder, a ipe lconnected tosaid topmost annulus for eading the collected fumes therefrom, and lScrapers connected to said shaft and extending adjacent to the up er side of the topmost annulus.

n testimony whereof I have hereunto af- 'fixed my signature this 13th day of June,

ROBERT MCKNIGHT. Witnesses:

L. M. SIMPSON, D. H. LANG.

TOO

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