US1596902A - Electric furnace - Google Patents

Description

Aug. 24 1926.

C. E. TAYLOR ELECTRIC FURNACB Filed v. 20, 1920 2 Sheets-Sheet 1 INVENTOR ATTORNEY Aug. 24, 192e, 1,595,902

C. E. TAYLOR ELECTRI C FURNACE Filed Noy. 20, 1920 2 Sheets-Sheet 2 INVENTOR ATTORNEY Patented Aug. 24, 19.26.

' i CEABLES EDWARD TAYLOR, 0F PENN YAN, NEW YORK.

ELECTRIC FURNACE.

Application led November 20, 1920. Serial No. 425,336.

This invention relates to furnaces and more particularly to improvements in large electrical furnaces yfor the production of carbon disulphide or for the treatment df other substances by heat.

It is an object of the invention to provide an improved furnace construction wherein the commercial production of carbon disulphide on a large scale can be expeditiously and economically effected.

It is a furthr 'object of the invention to provide a furnace of the character mentioned having features of structural superi'- ority and functional advantage.

Another object is to provide an improved design and construction of elect-ric furnace wherein the designed reaction'is expedited and wherewith the manual operation thereof is facilitated.

Other objects and advantages will be in part noted hereinafter in connection with the following description of the accompanying drawing which shows a typical preferred embodiment of the invention and wherein Figure 1 is a central vertical section of the improved furnace,

Fig. 2 is a top view thereof.

Fig. 3 is a transverse section on the line 3-3 of Fig. 1, and

Figs. 4 and 5 are respectively sectional views on an enlarged scale of certain of the feeding means for the material to be treated.

The invention is particularly designed to im rove the apparatus heretofore disclosed in nited States Patents 688,364 and 871,971 to E. R. Taylor.

There is provided an outer furnace cylinder 1 of sheet iron suitably constructed by welding or riveting and enclosed by a heat insulating layer 2, the latter in turn being covered by a protecting casing such as a sheet iron wall 3. The furnace also includes a second cylinder 4 of fire brick or other material preferably free from alkali and concentrically disposed within the outer cylinder 1 and spaced therefrom to provide a chamber v5 which, in the present instance, receives sulphur for treatment in the reac-l tion space. The space 5 is in communication at the bottom with a double walled casting 6 which comprises the furnace bottom and which has a central opening 7 about a lower cast 'iron electrode 8 affording communication for the sulphur to the reaction s aceat the bottom of thc furnace and above t e electrode. The furnace structure as described is supported on a foundation 9 with a lower compartment 9 to facilitate removal of the'slag or other refuse by means of a discharge valve constituting the subject matter of patent application filed by Frederick Pope, on November 20, 1920, Serial No. 425,341 to which reference is hereby made. Within the furnace wall 4, there is another cylinder 10 also of fire brick and suspended with its lower end resting on a casting 11 `which is attached to the lower end of a tube'12 in turn spaced from the inner walls of the cylinder 10 and projected at its upper end beyond the furnace where it is supported by the transverse cover 13. An upper electrode 14 is of carbon and is attached to a tubular conductor support 15 which at its upper end is suitably connected to a cable or the like 15 so that the tube 15 and the carbon electrode carried thereby may be raised or lowered as desired. The conductor tube 15, it will be noted, is also hollow and adapted for cooling by circulation of water or other medium through a central pipe 17.

The cylindrical space between the tube 12 and the inner cylinder wall 10 is also adapted to receive sulphur (in the present instance) from a pair of hoppers 16, the location of which is indicated in Fig. 2 and the particular construction of which .is more clearly shown in Fig. 4. For convenience of identification, the cylinder walls 4 and 10 are hereinafter referred to as casings, which afford reaction space therebetween.

Preparatory to starting, the furnace is charged, andfor this purpose dried coarse carbon or lump graphite is projected within the furnace throu h the space within tube 12 and outside'o the conductor tube 15. This coarse carbon drops by gravity around the carbon electrode 14 tothe bottom of the furnace and, as will be apparent, accumulates in a substantially conical pile over the.

lower electrode 8. In this'operation, the upper carbon electrode is preferably lowered to a position more closely adjacent the cast iron electrode. Thereupon the remainder of the furnace is filled with finer or amorphous dried carbon which is discharged through hoppers 18 symmetrically disposed at the upper end of the casing and of a construction such as indicated in Fig. 5. The hopper valves, as shown in Fig. 1, are also preferably counterweighted. As described, the annular space between the fire sab brick` casing 4 and the outer cylinder 1 as Well as the space between the inner fire brick casing 10 and the tube 12 are lled with sulphur.

Thereupon current is delivered to the electrodes and the mass of coarse carbon within the high heat area is increased, by raising the electrode 14, until substantially the entire conical pile is incandescent. This heat, as will be apparent, extends -in lesser degree throughout the furnace and it effects the melting of the sulphur at the lower end of the furnace and its consequent drying so that the latter enters the reaction field through the opening 7 about the lower electrode and .through a plurality of openings 19 in the bottom of the tubular casting 11. Furthermore, the dischar e of the sulphur into the reaction field is acilitated by reason of the fact that both of the entrance spaces as described are comparatively unobstructed due to the clearances there occurring during the gravitational carbon charging. The carbon disulphide, which is the product of the reaction, rises and `is drawn off through a top outlet 20 for condensation or other treatment.

Itlis to be noted that the walls of the inner fire brick casing 10 at the lower end are of lesser thickness. This construction is provided in order to insure melting of the inner fed sulphur only in proximity to the electrode 14 whereby the carbon surrounding the electrode, as well as the electrode itself, is to a material extent cooled. The conductor tube 15 also encloses a pipe 17 leading from the exterior whereby water circulation to the electrode is permitted and the temperature range thus limited. For similar reasons the lower electrode 8 is provided with a central recess at'it-s lower end whereby lcirculation of water or other cooling medium is permitted to limit the temperature of the iron electrode. Both electrodes are thus water cooled from outside e furnace, and furthermore, the entering Sulphur from above and below serves to exert an advantageous cooling effect on the walls adjacent the reaction space.

The upper end of the inner, fire brick casing 10 is provided with a recess l21 for the reception of sand or asbestos packing to allow for differences of vertical expansion between the iron inner tube 12 and the lire rick casing 10. It will also be understood that the conductor tube 15 is suitably insulated from the outer casing at the top of the furnace and that the casing is supported by a circular plate 22 resting upon the top of the furnace with the joint under the plate made ti ht by a proper cement.

T e carbon e ectrode 14 is preferably ided in its vertical adjustment at the ower end of the lire brick casing 10 as by a plurality of refractory elements 23 attached within the casting 11. The outer cylinder 1 may be provided at several points with openings 24 to draw off the melted sulphur in case there is a surplus over the requirements to meet the operating conditions of the furnace. To facilitate controlling the operation, also; a plurality of thermometers 25 are preferably provided within the outer casing anda plurality of pyrometers are extended within the brick casing 4. Of course the spacin about the stems of the pyrometers and t e thermometers are suitably packed to prevent any leakage of the sul hur.

n operation all openings are sealed to prevent the escaping of gas. In the first, or lower position. of the carbon electrode, a small quantity of the carbon is heated very hot in the center of the furnace and as the current is increased in voltage the carbon electrode is raised and the quantity of coarse carbon heated is greatly increased so that in the extremely high sition of the carbon electrode practically t e entire cone or pyramid of coarse carbonrat the bottom of the furnace is rendered incandescent.

It will be observed that the arrangement and structure described provides for a uniform heating of the entire mass of coarse carbon in the furnace and for substantially exact regulation of the temperature. As the furnace becomes hot, the sulphur melts and feeds to the reaction field where it is vaporized by the action of the heat generated between the electrodes and, passing upwardly to the carbon in the upper part of the furnace, it combines therewith in the form of carbon disulphide. The continuous operation of the furnace is facilitated by reason of the charging arran ments described, and moreover, the bo ily removal of the electrode 8 or the tube 12 and casing 10 is permitted by raising upwardly when necessary for repair or inspection.

It is to be understood further that .certain features of the invention are susceptible of modification, while retaininor the structural superiority and functional aldvanta es characteristic of the embodiment descri d, and within the scope of the appended claims.

Having described my invention, what l claim as new and desire to secure by Letters Patent is:

1. In a device of the character described, a vertically disposed casing having a fixed electrode at the bottom thereof, and a complementaiy electrode adjustable toward and from sai fixed electrode, and means for feeding material to a point above said fixed electrode, and means adapted tolfeed material from the topI of said casing in position normally to surround the lower end of said complementary electrode, and means for c on ning the material fed by said first mentioned feeding means to the space immediatelv surrounding said complementary electrode. 2. In a device of the character described,

in combination, a vertically disposed casing having lfire brick walls `and a bottom, a relatively small electrode fixed centrally in the bottom of said casing, a complementary electrode suspended centrally from said casing in registry with said first electrode and adjustable to and from said fixed electrode, and means for feeding material to be treated from the top of said casing in position to contact with said adjustable electrode, and means for confining the material fed by said first mentioned feeding means to the space immediately surrounding said complementary electrode.

3. In a device of the character described, in combination, a vertically disposed casing adapted to form a reaction chamber, having spaced outer walls and a double bottom communicating with the space between said walls, a centrally disposed opening affording communication between the double bottom and the interior of the casing, said space and opening affording a means of introducing material. to the casing interior.

4. In a device of the character described, in combination, a casing affording a reaction chamber, an electrode projecting within said chamber, a shell surrounding said casing and projecting into said chamber, whereby a passageway is formed around said electrode, and said material may be introduced in immediate proximity to the extremity thereof to cool the same.

5. In an electric furnace, in combination, a vertically disposed cylindrical casing supported at the bottom and having a reaction space at its lower end, an electrode extending within said casing at the bottom thereof, a complementary electrode suspended from above said casing and adjustable with respect to said first electrode, and a second casing suspended from the top of said first casing and enclosing said second electrode and s accd therefrom and means to feed material to the interior of said second casing.

6. In an electric furnace, in combination, a casing affording a reaction space and a pair of complementary opposed electrodes extending within said casin at the reaction space, andA means where y material to be treated enters said reaction space about said electrodes and in contact therewith for exerting a cooling effect on the latter. f

7. In an electric furnace, in combination, a Avertically disposed c Ylindrical casing, an electrode disposed within said casing and suspended centrally from the, top thereof, a tube enclosing said electrode and affording a passage for materiall to be treated, a second casing enclosing said tube and suspended from the top of said first casing and affording a assage for a second material to be treate 8. In an electric furnace, in combination, a vertically disposed casing having a reaction space at its lower end, an electrode extending to said reaction space and sus-v ing.

9. In an electric furnace, in combination, a casing having a reaction space at its lower end, a hollow cylindrical casingcentrally disposed within said first casing and suspended from the top of the latter, an ele'ctrode at the lower end of said second casing and means dividing the space within said second casing into separate entrances for different materials to be treated.

10. In an electric furnace, in combination, a vertically disposedvcasing having a reaction space at its lower end, separate means whereby material to be treated may enter said casing from above and be fed by grav- 4ity and separately to a position adjacent the reaction space, and means whereby another material to be treated may be fed separately to a position adjacent said reaction space and intermediate the feeds of the first mentioned materials to be treated.

11. In an electric furnace, a vertically disposed casing having a reaction space at its lower end and having an opening in its bottom wall and 'an electrode extending through said opening and having an upper end o increased transverse dimension overhanging the edge walls of said bottom about said opening.

12. In an electric furnace, in combination, a vertically disposed casing having a double bottom and an opening in said bottom communicating with the reaction space within said casing, and an electrode extending throu h said bottom and said opening but space from the edges of the latter and having an enlarged top overhanging the edges of said opening.

13. In an electric'furnace, in combination, a double wall casing adapted to receive a reaction material between-its walls, an electrode extending into the interior thereof,

a communication between the interior and` the space between the walls adjacent to said electrode, a second electrode movable to and fiom said first mentioned electrode and movable to and from the same.

In testimony whereof I affixlmy signaure.

CHARLES EDWARD TAYLOR.

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