USRE12519E - Manufacture of carbid - Google Patents

Description

No. 12,519. REIS'SUED AUGJ, 190s.

H. L. HARTENSTE'IN. MANUFACTURE OF GARBID.

APPLICATION FILED MAY 10 1906.

maa/w T 4% (TM 22 *7 I ITED STATES PATENT HERMAN L. HARTENSTEIN, OF (JONSTANTINE, MICHIGAN, ASSIGNOR, BY MESNE ASSIGNMENTS, TO ELECTRO CHEMICAL & DEVELOP- MENT COMPANY, or PIERRE, OF SOUTH DAKOTA.

SOUTH DAKOTA, A CORPQRATION I MANUFACTURE OF CARB|D.-

Specification of Reissued. Letters Patent. keissued. Aug. 7,,1906i Original N0| 8 19,222, dated May 1,1906. Application for reissue filed May 10,1905. Serial No. 316,223.

To all] whom it may concern:

Be it known that I, HERMAN L. HARTEN STEIN, acitizen of the United States, residing at Constantine, in the county of St. Joseph and State of Michigan, have invented a new and useful Manufacture of Carbid, of which the following is a specification.

This invention relatesto the manufacture of carbid.

The object of the invention is to produce' carbid of a superior quality for commercial purposes and in a most simple, 'eflicient, and economical manner. i

The invention consists, substantially, in the method of operation and procedure hereinafter set forth, and as illustrated in the accoin anying drawing.

T e single view of the accompanying drawing illustrates an apparatus adapted to the carrying out of my invention.

According to the ordinary-methods such as are commonly practiced the manufactureof carbid for commercial purposes, lune is mixed with carbonaceous material, such as coke, and the mixture isfused or melted in anelectric or other furnace and at ahigh degree of temperature,'the molten "mass bein usually ermitted to cool in the furnace an the coo ed product finally removed, broken up or crushed, acked, shipped, or used for use in the manu acture of acetylene gas or for other purposes. This method of operation 'is' obj ectionable, in many respects and results in the roduction of an inferior (grade or quality of nished product or carbi It is among the purposes of my invention I to simplify and improve the method of manufacturlng carbid, toavoid the waste and crudeness of former methods, to utilize in the most economical manner the natural advantages of a direct-and continuous method of treatment and operation, and to take every possible advantage of the condition in whic the material is placed by each step of the process in the succeeding steps of operation. In carrying out my invention I propose to employ limestonerather than lime, although in this respect I do not desire to be limited,

as my invention contemplates many other advanta es, even when lime 15 used; but in v I the usua method of burning lime limestone in' lumps or m p1ec'es of various s zes is used,

being charged into kilns with alternate layers of fuel, and'if the charges are uneven or too large the combustion isnot perfect, hence resulting in imperfect burning of the stone, and consequently resulting in an inferior quality of lime, at least for the purpose. of manufacturing carbid. Moreover, limestone in large and irregular-sizedpieces causes loss oftime in addition to being imperfectly burned,

thereby necessitating a sorting of the stone and running of kiln for a time on one size and then for a time on another size, for if there is any very great variation in the size of pieces or lumps of stone being burned the time required to burn the larger-sized pieces is lost for whatever percentage of small stones or pieces that may be present, besides involving an increased cost in the burning operation, as well as a waste of time and fuel; More- ,over, lime is frequently produced crudely in imperfect or temporary ilns ,of various constructions, and consequently is not of the superior quality desired or desirable for carbid manufacture, and in some forms of kilns employed the limestone comes in contact with the fuel employed in the burning o oration, and the resulting lime is injured by the ashes, frequently causing clinkers. In some forms of kilns gas is employed as the heating medium; but such kilns are usually of small capacity, inasmuch as the flame ofthe gas penetrates only asmall distance through the mass of stone being burned. .Moreover, it usually requires many days burning to re du'ce the limestone to the proper condition, and after ,the burning operation is completed the lime is permitted to cool down without in anyway utilizing the heat'required during the burnin operation, and this is particularly true w ere the lime after being produced 'is transported to the oint of location of the ver'ized at the carbid plant previous to the operation of conversion, besides requiring handling, and owing to its caustic qualities it is very injurious to thelife and health of the workmen, as well as to near-by vegetation. Moreover, as is Well known, lime readily absorbs moisture and carbonic acid, and when unduly exposed,i as isfrequently the case in 3'0 Generally 2 'or car on dioxid,

' the product is ready to trio or other furnaces,

the transportation and handling thereof, it causes ob ectionable'irregularities in the electric or other furnace in which the conversion is effected as, for instance, the blowing resultin from the escape of carbonic-acid gas thereby wasting coke, as well as the lime, and also frequently clogging and hanging up the furnace charge. Again, in the ordinary method of manufacturing carbid the lime is'usually mixed with the carbonaceous material in the cold, thereby necessitating mixing machinery, as well as the labor and handling of the materials, and also a very heavy'electric current for effecting the fusing or melting operation, which is an expensive part of the operation; For these and other reasons which might be recited I prefer to employ limestone direct instead of ime in carrying my invention into practical operation, although, as above stated, I do not desire to be limited or restricted in this respect. I

In carrying out my invention I propose to calcine'pulverized limestone and then to heat the same to incandescence in the presence of carbonaceous material-such, for instance, and, preferably, as pulverized coke, although other carbon-containing substances ma .answer the purpose. I therefore do not esire to belimited or restricted in this res ect.

speaking, and in its roadest terms, my invention ma be said to consist in crushing or pulverizing mestone, then heating the same to the point of incandescence, and then While in its heated condition sup plying the charge to an electric or other furnace in associationwith a carbonaceous substance, Where the mass is heated to the melt' ing-point to effect the desired conversion into carbid, and finally tap ing or running off the molten mass into .mo ds or otherwise, when be broken up, crushed, packed, shipped, or used'for commercial purposes. After the charge of mixed limestone and carbonaceous substance has been sufficiently heated to expel the gases'from the materials the heated char e may be delivered into a vat, reservoir, .ta or other suitable receptacle, may be delivered to one or more electric or other furnaces to be converted into carbid. In this manner-Iutilize as much as possible the heat 'units required in the preheatingopera-tion in raising and maintaining the temperature of the mass as deliveredinto the electhereby requiring less current in case of an electric furnace to effect 'the conversion of the mass into carbid. If desired and preferably, I supply to the mass during the reheating operation a small por' 'tion of car id. dust or fines, which is not suitable or desired for other use, in order to thoroughly expel and drive off any remaining carbon monoxid and carbon dioxid. The

' compositions an lr'om which said-heated charge:

e heated mass duri or immediately preceding f)? the delivery such mass into the distributing tank or vat; I have found that a composition composed of calcium carbid sixty per cent., black oxid of manganese, twenty per cent., (20%,) bituminous chlorate of potash, two per cent, (2 aluminium, three per cent., (3 answersthe purpose of a superheating compound for my urpose'. I do not desire, however, to be 'mited to any s ecific superheating composition or compoun as (possibly other substances or otherproportions of ingredients 'might equally well serve the desired purpose. The substances mentioned and the. proportions set forth I have found to b effic ent and satisfactory. In the accompanying drawing I have illustrated an arrangement of apparatus adapted to the carrying out of the principles of my invention; but I desire it to e understoodthat IIlinvention as herein claimed does not reside in the form of mechanism employed, the

particular form shown being mere y illustrative of an operative embodiment of appa-.

ratus capable of performing my invention.

Reference-sign-A designates a suitable hopper or bin adapted to receive the limestone after being crushed and pulverized to'the desired degreeof fineness. I havefound that limestone crushed to about twenty mesh well answers my urpose;-but my invention is not to be limited or restricted in this respect, as

ect by adding'a superother degrees of fineness or coarseness might be employed. Reference-sign B designates a similar tank adapted to receive carbonaceous material in a finely-divided stateas, .for instance, crushed or pulverized coke.

though it is obvious that other carbonaceous or carbon-containing substances may equall I well.answersuch, for instance, as charcoa coal, lampblack, or the like. 1 I have also found that the bestresults are obtained when the cokeor carbonaceous substance is ground or pulverized to about fift mesh or finer, though I do not desire to be imited in this respect.

C designates the preheatin -furnace. This furnace may be of any suita le, convenient,

In the form illusor ordinary construction. trated this comprises arotary drum or cylinder adapted to receive rotation in any suitable or convenient manner-as, for instance, from the drive-pulley D through suitably-ar- I havefoundcoke desirable for my purposes, al-

convenient manner. ,most economical arrangement the bins A B ranged gearing. The charges of pulverized limestone and carbonaceous material are delivered into the furnace Gin any suitable or Preferably and in the are arranged over thefurnace, and the charges are delivered or fed. therefrom into the furnace C by gravity. If desired, the charges maybe weighed as, for instance, by means. of the automatic dumping-scales E or otherwiseprevious to the introduction thereof into the furnace. Where a rotary drum is employed as a preheating-furnace, said drum may be rotated within a stationary sleeve, which sleeve communicates with the interior of the heating-drum and with which sleeve connects suitable receiving and delivery spouts for the material to be treated. The preheating-furnace C may be heated in any suitable or convenient manneras, for instance, by means of a burner F, arranged to deliver into said furnace coal-dust or fine particles of coal, and anair-blast, the fuel-coal being supplied in any suitable manner from a conveniently-arranged bin (Pb-as, for instance, by a suitably arranged conveyer H- and the air-blast being supplied in any convenient manneras, for instance, from a blower J. From the preheating-furnace C the mass of material when raised to the desired degree of temperature is delivered into a distributing vat or tank K, from which such mass is delivered in a heated condition through one or more pipes L to the electric or other furnaces (indicated at M) for the 7 conversion into c'arbid, the number of electrio or other furnaces M depending upon. the capacity of the plant, and the most econom ical arrangement is shown, wherein the preheating-furnace C is located above the distributing vat or tank K, and the latter is located above the electric or other furnaces. In this manner the. heated charge from the preheating-furnace may be delivered by gravity into the distributing tank or reservoir and thence by gravity into the electric or other furnaces, thereby avoiding the handling of the material and at the same time enabling advantage to be taken at each step of the operation of the condition in which the material is left by the preceding step of the operation.- In other words, the heat required to calcine the limestone in the preheating step of the process is practically all (retained in the material, andparticularly where. a superheating substance, agent, or compound is employed in the manner above set forth, until such material is delivered into and is acted upon in the electric or other fur nace to effect the final step of conversion.

After the material has been reduced to molten condition in the'electric or other furnace M it is tapped or runoff or otherwise delivcred into molds or othersuitable receptacles,

and the process, so far as the production of carbid is concerned, 18 completed.

The operation is as follows: The preheat if desired. This charge isithen agitated in any suitable manneras, for instance, in the case of a rotary furnace, by imparting a slow rotation thereto-and the temperature within the furnace increased until the charge is raised to the temperature of incandescence or thereabout. During this heating operation the carbonic-acid gas and other gases are driven off, and by agitating the charge as, for instance, by rotating the heater orfurnaceevery particle of stone is acted upon by the heat. This operation requires a comparatively short time, and the degree of tem perature maintained' may be readily indicated by a pyrometer, and it may also be determined when the gas has been sufficiently the furnace continuedas, for instance, by-

rapidly rotating the same in case of a rotary furnace-thereby thoroughly mixing the carbon element with the heated limestone. In practice I employ limestone and: coke in about the proportion of three parts, by weight, of the stone to one part, by' weight, of the carbonaceous material. This proportion,

however, may be varied without departure I from the scope of my invention.

Sometimes a small percentage or" ph'osphorus is present in limestone or lime, and which phosphorus is retained in the finished carbid. The presence of phosphorus in carbid is exceedin 1y objectionable on account of its infiamma ility and the danger of starting spontaneous combustion-therefrom. In accordance with my invention, as above ex-. plained, the aluminium constituent of the superheating flux serves to drive off or expel, any phos horus that 'may be present in the mass un er treatment. The proportion of ,superhea'ting flux employed may be varied throughout a wide. range and dependent upon the character or quality of limestone or lime bearing ore or substance employed. Under ordina conditions I have found the proportion of om fifteen to twenty pounds of superheating. flux per" ton of material treated. satisfactorily answers the desired urpose. The operation is as follows: The mestoneor' lime-containing ore or substance I (and, preferably'in a pulverized 0r granular 1 (also preferably crushed or pulverized)are ing-furnaee is placed in the receiving-bins. Y The preheatthen heated up to from 1,500 to 2,()()() ,temperature. A charge of the crushed or pulvcrized limestone is then dolivored into the heated furnace, being previously weighed, if desired, in the automatic scales. The mass in the preheating-furnace then su itably agitated-as, for instance, by slowly rotating the furnace in case a rotary furnace is thereof increased. by properly regulatingthe supply of coal and air through the burner or otherwise to an extent such as to bring the limestone to incandescence. The charge of powdered carbonaceous material, previously weighed, if desired, is then introduced into the preheating furnace and thorough 'ymixed with the incandescent lime in the presence of a very high degree of heat. The superheating compound is then added to the mass, and immediatel or delivered into the distributing tank or vat. If desired, the superheating compound may be supplied during the delivery of the heated mass into thedistri'buting-tank, or the suheat of the mass while contained in the disduced direct from limestone perheating compound'may be placed in the istributing tank or vat and the heated. mass delivered therein. This com ound or flux not only serves to retain the high degree of tributing tank or vat, so that, the mass is distributed into the electric or other furnaces at a high temperature, but also this compound or flux tends to drive off 01' expel any phosphorus that may be present. The heated mass, and while still'in a highly-heated condition, is distributed through the; distributingvat or tank to the variouselectric or other furnaces, in which the mass is subjected to the action of an electric current or otherwise heated to the fusing or melting point, and the melted mass or carbid is then run off into molds 0r sheets or otherwise and is ready to be broken up, crushed, packed, shipped, or used.

, From the foregoing description it will be seen that I provide'an exceedingly simple,

economical, and efficient process for the man-, l

ufacture of carbid wherein the carbid is prowithout the necessity of waste'of time, labor, and expense of first burning the limestone according to the usual methods to produce lime. It will also be seen that I take advantage of the condition and temperature of the material under treatment, in which such material is left by each step of the process in carrying out the next successive stepof the operation For instance, the heat developed during the ca cining and mixing operations-is 'retainedin the mass until themass is distributed tothe employcdr-and the temperature thereafterthe mass is dumped.

carbonaceous material,

electric or other fusing or melting furnaces,

' thereby requiringless current and involving less expense to effect the final step of melting or. conversion into carbid. It will also be seen that I am. enabled to produce a superior quality of'c'arb-id and a product free from the presence of phosphorus, and thecost of manufacturing the vastly reduced.

' I do not claim herein the superheating compound or composition of matter emphiyed, as the same forms the subject-matter of-a copending application executed of even, date herewith, Serial No. 116,665. Having now set forth the object and nature of my invention and the manner of carrying the same into practical operation, what I claim as new and useful and of my own invention, and desire to secure 'byLettcrs Patent, is

1.v In the manufacture of carbid from limestone and carbonaceous material, the heroindescrihei'l. process which consists in calcining the limestone to produce lime before the carbonaceousv material is added, then mixing with-such resultant lime before mospheric temperature, the proportion of and finally; while the mixture is still heated above atmospheric temperature, subjecting it to a fusing degree 'of heat, excluded from oxygen.

2. In the manufacture of-carbid from limestone and carbonaceous material, the hereindescribed process which consists in calcining )ulverized limestone to produce pulverized lime before the carbonaceous material is added ,then mixing with such resultant lime before it cools to atmospheric temperature coal, aluminium and chlorate of potash and.

finally subjecting the mass before it cools to a fusing degree of-heat.

4. In the manufacture of carbid the herein-described process which consists in calcining limestone, mixing with the resultant lime before it cools to atmoshperictemperature, a carbonaceous material, and adding a superheating flux to the mass while still heated and finally subjecting the mass. to a fusing de ree of-heat excluded from ox en. I s Yr.

5. In the manufacture of carbid from limestone'and carbonaceous material, the hereindescribed process wlnch consists in calcining the limestone to produce lime, then after the finished product or carbid is it cools to at.

excluded from oxygen.

" lime is produced, and whilethe lime is still heagedabmie atmosphelgc temperature, ini ne sses, this 5th (lay of May, 1906. tro ucin t ereinto car ,onaceous materia IN T end mixiig the same therewith, and while the t HERMAN HAR lEL STEIN 5 mixture is still heated, raising its tempera- .Witnesses:

ture to a fusing degree of heat. JAY C. UPTON,

In testimony whereof I. have hereunto BERTRAM B. BUTCHER.

signed my neme in the presence of two wit-

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