US968485A

US968485A - Furnace.

Info

Publication number: US968485A
Application number: US46795108A
Authority: US
Inventors: James B Ladd; David Baker
Original assignee: Ladd & Baker Inc
Current assignee: Ladd & Baker Inc
Priority date: 1908-12-17
Filing date: 1908-12-17
Publication date: 1910-08-23
Anticipated expiration: 1927-08-23

Description

J. B. LADD & D. BAKER. FURNACE.

ABPLIOATION FILED .DEO 17 -1908 Patented Aug. 23, 1910.

WITNESSES: Y

ATTOR/VE 2 UNITED STATES ATENT OFFICE.

JANIES B. LAIDD AND DAVID BAKER, OF PHILADELPHIA PENNSYLVANIA, ASSIGNORS T0 LADD & BAKER, INCORPORATED, A CQBPORATION OF PENNSYLVANIA.

FURNACE.

Applicgtion fileafiaeeember 17, 1908. Serial No. 467,951.

To all whom it may concern:

Be it known that we, JAMES B. LADD and have i vented a new and useful Improvement in Furnaces, of which t he,following is a specification.

This invention has reference to the treatment of ores, and ref more pafticularly to a furnace or kiln for treating or roasting iron pyrites, for the purpose of effectually freeing the iron of sulfur, and delivering the latter in the form of a rich sulfurousacid gas.

The invention consists of a kiln or fur nace embodying a roasting chamber in which the ore is treated, and an improved arran ement of temperature controlling flues, y means of which the degree of heat to which the ore is subjected in the roasting chamber may be nicely and accurately controlled, according to the nature of the ore being treated as regards the quantity of sulfur therein, and the changing conditions which take place as the roasting operation progresses.

Referrin to the drawings: Figure 1 is a side elevation of our improved furnace. Fig. 2 is a longitudinal section through the same on the line aa of Fig. 3. 'Fig.

3 is an end elevation of the receiving end of the furnace, that into which the raw ore is delivered. Fig. 4 is a similar view of the discharge end of the furnace, that where the residue is discharged. Fig. 5 is a transverse section on the .line 6- of Fig. 2. Fig. 6 is a longitudinal section through the nozzle and its controlling valve on an enlarged scale, showingthe valve set so as to permit the heated air from the annular chamber 35 to enter the nozzle and be discharged into the heating chamben. Fig. is a similar view showing the valve setso as to deflect the heated air'from the annular chamber and discharge it to .the outside.

In the accompanylng drawings: 1 repre-Q sents a shell or cylinder constituting the.

furnace or kiln proper, which is sustained as usual at a slight inclination downward from its receiving end, and rotably sup ported by 'means' of rollers 2, or by other suitable means, so that may have imparted to it a slow rotary motion, convene iently by means of a drive pinion 3 engag1 DAVID BAKER, of Philadelphia, county of" Philadelphia, and State of Pennsylvania,

ing a rack 4 on the exterior of the cylinder, this motion of the cylinder causing the ore, which is delivered into'the up er receiving end, to travel slowly and um ormly to the lower delivery end, being subjected in. its passage through the cylinder to a tumbling or agitating action. T

At its receiving end the interior of the cylinder communicates with a chamber 5 inclosed by a fixed cylindrical casing 6, formed with an upwardly extending neck 7 Patented Aug. 23, 1910.

into which the raw ore is fed from a feed hopper 8 at the side of the neck, an inclined chute 9 being fixed within the chamber 5 and extending into the roasting chamber, to receive the ore from the neck and deliver the same tothe roasting chamber. The said neck serves also as a means for the escape of the sulfur-gases, which pass upwardly into a pipe 10 connecting with the neck, from which they may be collected for use. At its delivery end the cylinder communicates with a chamber 11,- inclosed by a fixed casing 12, -for receiving the residue-or roasted ore, which latter is discharged from the receiving chamber by means of a bell discharge valve ].3.

The cylinderl is formed of fire-brick in Y which are arranged side by side, as shown in Fig. 5, a series of longitudinal

temperature controlling flues

14, 15, 16, 17 etc., certain of said flues, every alternate one as indicated by the odd numbers, beingfor the circulation of either air or heating gases; while the other flues are for the passage of air only, the primary purpose of this construction and arrangement being, as will be 'more fully described hereinafter, for the proper regulation of the temperature in the roasting chamber to-meet the varying conditions encountered in the operation of the furnace as regards the character of the ore being treated, etc. At its ends, the brick- :work or shell of the cylinder is thickened or 'eniarged, the

flues

14, 16, 18, etc., being defiected outwardly at the receiving end of the'cylinder, and passing through the thickened portion of the same, as at 72, whereby they will terminate in a circular line outside of and beyond the ends of the alternate fiues 15, 1?, 19, etc., which latter pass straight through the thickened portion of the shell at this point. At the opposite or delivery end of the furnace, this arrangement of the fines is reversed, the

flues

15, 17, 19, etc, being deflected, as at 0, and terminating in a circular, line beyond the ends of thealternate fiues 14:, 16, 18, etc., which latter pass straight through the thickened portion of the cylinder at this point, the purpose of which construction and relative arrangement of the fines is to enable the proper circulation of heating gases and air, as will be presently described.

25 represents a starting or auxiliary furand will escape from the opposite ends of the fines into an annular chamber 28, surrounding the cylindrical casing 6 at the receiving end of the furnace, which latter chamber is inclosed by a fixed casing, and contains openings in its rear wall, with which the ends of the lines 15, 17, etc, are adapted to register as the cylinder is rotated. The gases from this chamber 28 pass downwardly through an escape pipe 29 connected with'the chamber, from which pipe the gases pass to a stack (not shown). The purpose of this auxiliary or starting furnace is to heat the roastin chamber sufficiently to cause the ignition o the pyrites when the raw ore is fed in, and inasmuch as with the ordinary commercial pyrites the temperature of combustion, after being once started, is readily maintained and without auxiliary heat, and as it frequently becomes too high, thus fusing the mass of burning material and. seriously retarding combustion, 1 propose to provide for the introduction into the fines 15, 17, etc., of cold air instead of the gases, the efi ect oi which will be to reduce the temperature and prevent a too intense combustion. The air may-be introduced by any appropriate means, for instance, by the natural suction of the stack, a suitable ad mission opening 30 being formed in the annular chamber 27 to receive the air from the scenes chamber. This is efiected by means of a fan in its rear wall adapted to register with the deflected ends of the fines 14L, 16, 18, etc, into which fines the air will pass as the cylinder 1 rotates, and passing through the fines, will become heated by the heat of combustion in the roasting chamber, and will escape from the opposite ends of the fines into a chamber 35 inclosed by a fixed casing at the delivery end of the furnace, this chamber being formed in its front wall with openings adapted to register with the ends 01 the, fines. From the chamber 35 the heated air enters a nozzle 36 extending through and sustained by the casing of the chamber, and projecting downwardly and inwardly with its delivery end terminating within the delivery end of the roasting chamber, by which means the heated air, in the form of a blast, will be discharged into the roasting chamber, onto the ore therein. The cold air entering the fines 14, 16, 18, etc., at the receiving end of the roasting chamber, has the effect of reducing the temperature at that point, where, under certain conditions itis likely to be too high, and by becoming heated by this high temperature, and being introduced into the delivery end of the roasting chamber, raises the temperature at this point, where, under certain conditions, it is likely to be too low.

it is seen, therefore, that there are enibodied in the construction described, two means for. controlling the temperature in the roastin chamber, one the auxiliary fun nace and l ues in the shell connected with said furnace, which may be employed to heat up the roasting chamber or reduce the temperature therein at will, as by the banlring of the fire in the auxiliary furnace and the admission of cold air into said lines; and the other by means of the fan or blower connected with the alternate flues in the shell of the cylinder, he cold air passing through said fiues, acting to take the heat from the part of the furnace where it may be too great, and delivering the same to that part which may require a high. temperature.

Under certain conditions it may not be necessary or desirable to introduce the heated air flowing through fines 1 1, 16, 18, etc, into the roasting chamber, although it may be desirable to effect such a degree of equalization of the temperatures at the two ends of the roasting chamber as would result merely from the passage of this air through the lines. Under these circumstances, the communication between the annular chamher 35 and the nozzle may be controlled by a valve 37 of such form, that the heated air will be prevented from entering the roastin'g chamber through the nozzle, and will be allowed to escape to the outside through the outer end of the nozzle. Theconstrucr tion of the parts whereby this result may be effected, is shown articularly in Figs. 6 and 7, where it will lie seen that the annular chamber 35 communicates with the nozzle 36 by means of a number iof openings extending through the wall of the chamber, which openings are adapted to re "ster with corresponding openings in a ho low valve 37 mounted in t e outer end of the nozzle so as to rotate therein, -in order that the openings in this valve may be brought into register with the openings in the nozzle, or may be adjusted out of register, as shown in Fig. 6. The inner endof the hollow valve is conical in form, so that when the openings therein are out of register, the heated air may pass from the chamber 35 into the nozzle 36. When, however, the hollow valve 37 is turned to the position shown in Fig. 7 to bring the openings therein into register with those throu h the walls of chamber 35, tge 'heailteii1 air d t rou t e re 'sterin openings an escape outwfrdly thri ugh' the open end of the valve. i

In the construction shown, particularlyin Fig. 2, the rear walls of the two

annular chambers

33 and 28 are disposed in a single plane transverse to the axis of rotation of the cylinder which latter has its receiving end disposed in a similar plane and bearing flatly and closely a ainst the said walls, the abutting surfaces eing of cast iron, machine-ground, and being maintained in close abutting relations, as the cylinder rotates. This construction, in connection with the fact that these surfaces 'are extended and of considerable area by reason of the provision of two concentric annular chambers, and

the thickened end of the cylinder, reduces to a minimum the liability of leakage of air into the c linder from the outside, so that there will e no danger of the dilution of the outfiowing freed gases by air. It will beunderstood of course that the detailedeonstruction of our improved fursa e-may be variously changed and modified bythei skilled mechanic wlthout departin the limits of my invention, provide its functions and operations are substantially as above set forth, and it'is to 'be understood'that the invention is not limited to any specific form or arrangement of the parts, except in so' far as the limitations are sf xacified in the claims.

Having thus described our invention, what :we claim and desire to secure by Letters- Patent of the United States is as follows:

.1. In combination with a furnace having a heating chamber provided with two series of longitudinal flues surrounding the chamber, means for the independent circulation om chamber 35 will flow and discharge of different temperature controlling me' two series of flues.

2. In combination with a furnace having a heating chamber provided with two series of longitudinal flues surrounding the chamber, means. for circulating a temperature controlling medium through one series of flues in-one direction, and means for circulating a different temperature controlling medium through the other series .of flues in anopposite direction, and independently of the first controlling medium, the discha'r e of said controlling mediums being indepen ent of each other.

3. In combination with a furnace having 'a heating chamber provided with two series of longitudinal flues surrounding the chainher, the individual flues of one series alter mating with the individual flues ofthe other series, means for circulating diiferent temperature Iiontrolling mediums through said series of tions.

4. In combination with a furnace having a heating'chamber provided with two series of longitudinal flues, means for circulating ues respectively in opposite direc" iums respectively through the a heatin medium through one series of flues in one irection and means for circulating an independent cooling medium inthe op posite direction through the other series of flues, the discharge of the heating and cooling mediums being independent of each other. I v,

5. In combination with a furnace having a heating chamber provided with longitudinal flues surrounding the same, means for introducing a -cooling medium into one endof said flues and dlscharging the same at theopposite end of said flues into the interior' of the heating chamber.

6. In combination with a fujrnace'provided with a heating chamber having lon- I gitudina'l flues surrounding the chamber, means for introducing a cooling medium into said flues at the receiving end of the chamber and discharging the same into the delivery end of the heating chamber.

7 In combination with a furnace having a heating chamber provided with longitudinal flues surroundin the same, means for introducin cold air into the flues at the receiving en of the heating chamber, and a nozzle communicating with the op osite ends of the flues and arranged'to eliver the heated air into'the interior of the heating chamber at'its delivery end.

8. In combination with a furnace provided with a heating chamber to receive the raw ore at one end and discharge the residue at the'opposite end and having twoseries of longitudinal flues surrounding the chamber side by side and terminating at 'theinopposite ends respectively in two different circular planes, means for the intro- I 1888.4t8i5 duction of cold air into one series of fines at the receiving end of the furnace, means whereby the air discharged from the opposite ends of said lines may be introduced into the heating chamber, and means for in troducing heating ases into the ends of the other series of fines at the discharging end of the furnace.

9. In combination with a furnace provided with a heating chamber to receive the raw ore at one end. and discharge the resi due at the other end, and having two series of longitudinal surrounding fiues, means for the introduction of cold air into one series of fines at the receiving end of the furnace, means whereby the air discharged from the opposite ends of said fiues may be introduced into the heating chamber, and means for introducing heating gases into the ends of the other series of fiues atthe discharging end of the furnace. I

10. In combination with a furnace having a heating chamber provided with surrounding longitudinal fines, means for the int-roduction of air into said fiues at the receiving end of the furnace, means whereby the air issuing from the opposite end of the said fines may be discharged into the heating chamber, and means for deflecting the air in its passage to the heating chamber and dis charging the same to the outside.

11. In combination with a furnace having a cylindrical rotating heating chamber 'provided with surrounding fines, means for the introduction of cold air into the ends of the lines at the receiving end of the furnace, a nozzle connected with the opposite ends of said fines and arranged to direct the air into the heating chamber, and a valve for con trolling the flow of the 'air through the nozzle.

12. It furnace having a cylindrical. rotary heating chamber provided with two series of lines having their ends at one end of the furnace termimitingrespectively in difi'erent circular concentric lines.

13. A. furnace having a cylindrical rotary heating chamber provided with longitudinal surrounding fiues disposed in a circular field at a point between the ends of the furnace".

and terminating at the ends of the furnace respectively in different circular concentric lines. v

M. A furnace having a cylindrical rotary heating chamber provided with two series of longitudinal fiues surrounding the cham her, with the fiues of one series alternating with those of the other, the fines of one series terminating at theend of the furnace in 'one circular line and the fines of the other series terminating at the same end of the furnace in a difierent circular line concentric with the first.

15. A furnace provided with a rotary cylindrical heating chamber having longitudinal fines surrounding the chamber side by side and terminating at opposite ends in medium into the same fiues to retard combustion.

18. In combination with a furnace provided with a heating chamber having sur rounding longitudinally extending fines, means for circulating either air or heating gases in one direction through certain of said lines, and means for circulating cold air in the opposite direction through the other fines.

19. In combination with a furnace provided with a heating chamber having surrounding heating fiues, an auxiliary furnace and connections between the auxiliary furnace and heating lines to deliver the prodnets of combustion to said fiues.

20. In combination with a furnace pro vided with a rotary cylindrical heating chamber having two series of surrounding longitudinal fines arranged side by side with the opposite ends of the fiues of one series terminating respectively in lines concentric with but different from the lines in which the opposite ends of the other series of fines respectively terminate, the said furnace having two fixed chambers at one end with which the two series of lines respectively communicate at that end, and having at the opposite end. two fixed chambers with which the two series of fines respectively communicate at that end.

i :21. A furnace provided with a cylindrical rota y heating chamber having two series of surrounding longitudinal lines, the said furnace being further provided at each end with two chambers communicating respectively with said series of fines.

22. In combination with furnace having a rotary cylindrical heating chamber formed with two series of longitudinal fines extending side by side and surrounding said chamher, an air blower connected w1th,the ends;

of the fiues of one series at the receiving end of the furnace, means at the opposite ends of said fines for directing the air from the blower into the interior of theheating chamher at its delivery end, and an auxiliary furnace connected with the ends of the other series of flues at the delivery end of the furnaces, the o posite ends of said. last named series of ues being arranged to discharge the products of combustion passing through them from the auxiliary furnace.

23. In a furnace the combination with a fixed casing at the receiving end formed with an annular chamber having its rear wall disposed in a plane transverse to the axis of the chamber, of a horizontal rotary cylinder constituting a heating chamber and formed with longitudinal surrounding flues adapted to communicate with the annular Y chamber, the end of said cylinder being formed to abut flatly and closely-against the 15 wall of the annular. chamber; whereby the leakage of air-into the heating chamber will be prevented. i y

In testimony whereof we hereunto set our hands this twentyrfifth day of November, 20 1908, in the presence of two attesting witnesses.

JAMES B. LADD. DAVID BAKER.

Witnesses:

Lomsn B. Momus, S. HORACE MYERS.