US1706421A - Trent - Google Patents

Description

March 26, 1929. w E TRENT ,7o6,42

APPARATUS FOR DIS' I'ILLING MATERIALS Filed Jan. 20, 1921 2 Sheets-Sheet 1 adaf n March 26, 1929. w 5. TRENT v ,7o6,42

APPARATUS FOR' DISTILLING MATERIALS Ffied Jan. 20. 9 ?Sheets-Sheet 2 Patented Mar. 26, 1929.

* UNITED STATES WALTER I'lDWIN TRENT, OF WASHINGTON, DISTRICT OF COLUMBIA, AS SIONOR TO v TRENT PROCESS CORPORATION, OF NEW YORK, N. Y., A CORPOEATION OF DELA- WARE.

PATENT OFFICE;

AP IE'ARA'L'US FOR DISTILLING MATERIALS.

Application filed January 20, 1921. Serial No. 438,(517.

V The invention relates to an apparatus for the treatment of materials containing a volatile content, such as coals,oils, mixtures of coal and oil, ores, etc.

The invention more particularly consists in improved apparatus for subjecting finely comminuted carbonaceous material to a relatively low heat treatment to obtain a maxi- `mum yield of oils from the carbonaceous 'material with a minimum yield of fixed` gases, and to recover the residue in its finely divided state in a carbonized form.

My improved apparatus is particularly adapted for use in carrying out a process for the treatment of comminuted carbonaceous materials, such as coals, in which it is a salient feature not only to increase the total yield of oil products, but to obtain a different product in that the oils yielded carry a substantially greaten percentage of low boil-- ing point oils than would otherwise be produced by present day processeswhere larger size materials and higher temperatures, are.

employed. These improved results are obtained by treating the coal or like material having a hydrocarbon content while in an exceedingly fine state of division, in keeping the material in motion and under agitation` while undergoing a heat treatment, and in employing temperatures just suflicient 'to Volatilize the oils attheir respective boiling points from Vcoal particles which are so fine in size as to require only the minimum of heat penetration, thereby avoiding the eXcessve temperatures whch are necessary when heating coarse material, and which excessive' temperatures causes two general changes in the oil vapors, one being changing; vapors into fixed gases, 'and the other converting part of the low boiling point oil vapors into higher boiling point vapors.

The apparatus preferably consists of a plurality of alternate stationary and rotary heated hearths, over the surfaces. of which, the material progressively advances. The stationary hearths are provided With rabbles which serve to advance and assist to heat the material during its passage over the surfaces of the movable hearths, and the movable hearths are likewise provided with rabbles which serve to advance and assist to heat the material during its passage over the stationary hearths. Coal and all other materials, when treated in coarse sizes, say approxmately 4, requre relatively low temperatures to treat the exterior surfaces' tures, while volatile products come off as" the particles attain the low temperature, they are then changed in character by the higher temperature, the high temperature necessary for penetrating the coarse particles having a further detrimental effect, that of causing the particles undergoing treatment to f-use and agglomerate, which can be avoided by carrying out such treatment in the present apparatus.

To avoid these changes of the oil vapors I, reduce the coal or other material to the economic limit of fineness so that in effect the particles are practically all surface and no interior, thereby enabling the application of the minimum temperature to cause the vaporizations and' consequently avoiding Conversion of vapors to fixed gases and light boiling pointoils to higher boiling point oils, and'also preventing the fusion or agglomeration of the carbonized particles.

The material, when introduced to the retort, travels successively and alternately over the upper surfaces of the moving and stationary hearths and is subjected, throughout its travel, to heat transmitted from the interiors of both moving and stationary hearths, which interiors are heated by hot gases travelling therethrough, With this Construction, the top and bottom surfaces of each hearth and also the rabbles constitute i actual heating surfaces. When great heat economy s desired and when vapors produced at different temperatures are to be col-' lected separately, the material being treated is caused to run counter-current to the dithose ot the lowest boiling point first, and as the material reaches the hotter zones, those of higher boiling points and so on, the lastto be volatilized and taken oli being of course those of highest boiling point at the hottest heat zone in the path of travel.

The present invention thus enables materials, such as coals, oils, shales, oil sands, or mixtures of oil and coalto be continuously treated to yield their volatile constituents at a minimum temperature and to enable the vapors which pass from the material atvarious temperatures to be separately collected. As an example of the operation of the apparatus in carrying out the process above mentioned, if finely comminuted coal is being treated, the same passes through the retort in a direction opposite to the path of incoming gases and is maintained in a state of motion and agitation during its heat treatment, so that when this material is subjected to a temperature of approximately 350 C., the vo'latiles will be quickly vaporized, While the residue will not agglomerate, but is collected in the form ot carbonized particles in substantially the same state of sub-division as the green fuel introduced to the retort, but of course freed of all of its Volatiles or such portions as may be desired. The volatiles thus recovered are in the form of valuable oils, With a minimum of fixed gases. The oils of low boiling points thus produced are exceedingly valuable, whereas if the material were subjected to a high temperature, these low boiling point oils would be converted into fixed gases and other less desirable coal products.

While I have described an apparatus as particularly applicable to the treatment of pulverized materials, it will be understood that the same is also adapted to use in the distillation ot liquid oils, in which event the oil is introduced to the retort and passes through Zones of progressively increasing temperatures, while the vapors are discharged from said zones through independent discharge conduits permitting these va pors to be. collected Without being commingled.

In the drawings, Figure 1 represents a vertical sectional view of the apparatus; and,

Figures 2 and 3 are detail views.

Referring now more particularly to the drawing's wherein like reference characters indicate corresponding parts, the nmneral l designates a distillation apparatus or retort having suitable walls composed of any desired material and mounted in any approved manner, for example upon the base 2. Supported within the retort upon an inner casing are a plurality of circular double walled hollow stationary hearths 3, which may be composed of metal, and each hearth has its upper and lower surfaces disposed at an angle so as to merge at the inner termination 'cating with the gas flues 32.

thereot in a circle, so that in section it shows as a point. The hearths are Secured to the inner casing or plates 3', by rivets, welding or the like, and both this inuer casing and the outer wall ot the heartl are formed so as to provide 'lues 3 on opposite sides of the retort, as shown in Figure i for the passage of heating gascs. Positioned within the lues are a plurality ot spaced baflies 4 serving to detlect the heating gascs and to cause said gases to pass through openings in the inncr easing or plates 3' into the hollow portions ot the stationary hearths 3. The stationary hearths 3 are made ot hollow tormation as to provide passages for heating gases, thereby heating not only the upper surfaces of said hearths over which the material being treated is travelling, but also transmitting heat through the lower surfaces of said hearths to material on the corresponding next lower rotary hearths. The heating gases are preterably introduced to the retort through a feed pipo 5, which is provided with branch communications 5' and 5 for introducing the heating gases to both the stationary hearths and the rotary hearths, which will be more i'ullv hereinafter described. l

Rotatably mounted within the retort is a hollow column 6, seated within bcarings 7 at one end, and the structure is provided with said seals 8 at each end of the column :tor preventing the escape of the heating gases introduced thereto. Carried by this column are a plurality of bafilcs 9 adapted to defiect theheating gases so as to cause said gascs always to pass into the hollow interiore of the rotary hearths, to be now described, in a circuitous path.

Mounted upon the column is a pluralitv ot rotary hearths 10, which are ot' substantihllv thesane general. arrangement as the sta tionary hearths 3. Rotary hearths are in form the reverse of the stationary hearths. the inclination of the upper and lower surfaces merging at their outer tcrninations. thus providing a passage ll for the material, between the rotary and stationary hearths. which are substantially equi-distant froni one another at all points. The rotarv hearths are hollow to provide passagcs l' for the heating gases, such gases being` also introduced to the interior of the stationary hearths 3, through openings G' communi- These gascs are conveyed to the retort at the lower end thereof and travel upwardly through said retort in a direction counter-current to the path of the material introduced thereto, .ti nally discharging through the fiuc discharge 12, thus providing in the retort heating gases which progressively decrease in temperature as they travel through the retort. The rotary hearths may be rotated in any approved manner, but in the present disretort which 'may be pulverized coal, an

amalgam of oil and coal, or oil and graphite, finely divided carbonaceous particles, shale oils and the like, is introduced through the supply pipe into the passageways 11 formed between the, various stationary and rotary hearths and progressively travels downwardly through the retort while being subjected'to'the heat of the gasesntroduced throu h the gas feed 5. The material is 'first eposited upon the inner part of the surface of the uppermost rotating hearth 10, passing between said hearth andthe upper inner surface of the retort wall, which retort wall is furnished with rabbles, then around the point of the upper rotary hearth,

"and then deposited upon the surface of the succeeding stationary hearth, travelling in this manner' throughout its passage through said retort. To prevent, 'if desred, ag-

glomeration of solid 'particles when a pulverized material is being treated, I place upon the bottom surface of each stationary hearth a plurality of hollow rabble s 1 7, which serve to keep the'moving materal n a constant state of agitation and also to transmit heat thereto while said material is passing over the surface of a' movable hearth. `These hollow -rabbles may be, f desired, in free communicatonwith the interior of the hearths and derive-heat from theheating gases flowing therei n as indicated. To prevent agglomeraton of the material while travelling over the surface of asucceeding' stationary hearth I-also provide rabbles 17' attached to the low'er surthereto.

fa'ces of the rotary hear-ths, which constantly agitate the materialand' alsotransmit heat The 'rabbles 17 and 17' may be adjustably mounted upon the hearths, or spaced varying distances f rom o ne another so as always to cause the material passing over the hearth to be moved in the passageway 11 thereby preventingaccumulations` of said material between the rabbles on either hearth. These rabbles maybe set at 'varying angles, and the position and number of rabbles are dependent upon Operating con- The material when introduced is tort, over 'the alternate stationary and rotaryhearth surfaces,`through the passage- 'ways 11 and as a result of the countercurrent travel of the heating gases the material 'is subject to a progressively increasing temv perature which is highest at the point Where the material is being discharged.

lVhen treat-ing' materials for recovery of their Volatile constituents, it is desirable to remove the volatilized vapors at various points in the apparatus so that vapors of one character removed at one temperature may be separated 'and segregated from vapors removed at another temperature. With this in mind, there is disposed as communicating With the passageways 11, a plurality of independent vapor take-oti' ppes 12, each pipe preferably leading to a separate point of'collection'and storage. This permits the vapors to be discharged from the retort, as produced and prevents the various vapors volatilized at different .temperatures from commingling. Any number of these discharge pipes may be employed, and they may be 'disposed in any manner desired.

It--Will be appreciated that the heated vgases indirectly heat the material passing through the retort by conduction through the exposed surfaces of the movable and stationary hearths. The material is in a state of movement and agitation when passing'through the retort so that in the event V a material such as comminuted coal is being treated, the `residue is discharged from the retort by the elongated deflector 19 attached to the lower stationary hearth, and is collected in the receiver 20 in the form, if so desired, of finely divided carbonized particles which have not agglomerated or fused together. The recovery of the residue in finely-divided form with absence of agglomeration or fusion is made possible by means of the relatively low temperature to which the material is subjected while undergoing treatment, the fincness of the material, and the uniform and gradual application of the heat thereto, such unifor'mity of heat control being brought about ,by my improved means' for transmitting heat to the material as' well as for agtating same during' its passage through the retort.

as'these coal particles are kept in a constant state of agitationthe temperature is not sufficiently high to cause a material agglomeration thereof. The degree of fineness of the material controls to a certain extent the temperature necessary and the time required to remove the volatiles. When coal ranging 'between 100 to 200 mesh is treated, the desired result can be obtained with a gas temperature not higher than appro'ximately 450 C., with a treatment of approximately minutes. The applied heat being approximately %O C., the' temperature actually imparted to the material is approximatcly 350 C. By treating the coal While in a. Very fine state of division, under agitation and at a. low temperature, a maximum quantity of light oils is recovered from the coal With a minimum percentage of fixed gases. This is possible only because of the low temperaturetreatment and the fineness of the materials 'for reasons previously pointed out' This low temperature also enables hearth sections to be constructed of metal of a character favorable to heat conduction as the heat is not sufliciently high to attack metal hearths.

The heating gases are, as has been before stated, of a temperature approximately 450 C., so that the heat actually imparted to the pulverized material is approximately 350 C., and this has been found by me to be a temperature sufiiciently high to vaporize the Volatiles Without changing the character thereof, and to also prevent fusion of the carbon residue. r

lVhile I have disclosed the preferred embodiment of the invention, it Will be understood that the same is susceptible of change within the scope of the following claims Without d'eparting from the spirit thereof.

Having thus described the invention, What I claim is:

1; A retort for treating comminuted materials, comprising a plurality of holloW statio-nary hearths and a plurality of holloW rotary hearths, said rotary hearths being so positioned alternately With respect to said stationary hearths as to form a confined passagcway therebetween, means for causing the material passing through the retort to alternatelyfiow across the surfaces of the rotary and stationary hearths and means carricd bythe l''earths for both heating and agitating the material moving across the upper surfaces of hearths next below, means for supplying comminuted material to said retort to flow through said confined passage- Way and means for admitting a heating `mediu1n te the interiors of said holloW 'a confined, inclined, sinuous passageway therebetween for feecl ng the material to be treated thercthrough zigzag in vertical section; hollow, conical rabbles projecting downwardly from the inclincd lower surlaces of said hollow hearths to substantially the upper inclincd sui-faces of the next adiacent lower hearths; means to revolve said column and attached hearths; means to indircctly heat said material consisting solely of means to adnit heating gases to the interier of said hearths; means to feed inaterial to and through said sinuous passage Way; means for discharging and separately collecting Vapors from the retort at progressire intervals during the travel of the inaterial therethrough and means for discharging the treated material from the retort.

3. A retort for distilling carbonaceous materials, comprising a. cylindrical casing, having a plurality of hollow, conical, annular hearths attachcd thereto, project-ing' radially inwardly thereof at spaced distances, a re- Volvable column mounted substantially centrally of said casing, haring hollow, conieal, annular hearths attached thereto projecting radial'ly outwardly in said'casing at spuccd distances into the space between said stationary hearths said revolvable and sta tionary hearths being so spaced as to form a confined, inclined, sinuous passageway therebetween for 'eeding the material to be treated therethrough zig-zag in vertical section; means to revolve said column and attachedi hearths; means to indirectly heat said material consisting solely of means to admit heating gases to the interier of said hearths; means to feed material to and through said sinuous passageway; means for discharging and separately collecting Vapors froni the re tort at progressive intervals during the travel of the material thcrethrough and means for discharging the treated material from the retort.

4. A retort for distilling carbonwcous muterials comprising a casin a plurality of' ,superposed alternately disposed stationary and rotatable hearths so spaccd as to dcfine confined sinuous passugeway thercbctwcen for material being led the'ethrough, said hearths being holloW and consisting of highly heat conductivc material, hollow rahbles uttached to the lower sides of said hearths and communicating therewith, means for rotating said rotatable hearths as a. unit, means for udmitting heating gascs to the interier of the lmvernost heurth of each of the respective sets of stationary and rotatable hearths, means for causing said gases to pass suecessivelj through each hearth and the rabbles associated thorcwith of each set, means for sealing said sinuous passagewty against ingress of heating gases or air. and means at progressire inte'vals in said retort for withdrawing and separately collecting vapors evolvcd from material passing therethrough.

5. A retort for distilling carbonaceous materials comprising a cylindrcal casing, a plurality of superposed, spaced annular hearths attached to the inner surface thereof, a hollow rotatable column disposed centrally within said casing and having a plurality of spaced, hollow annulahearths attached thereto and projecting radially outWardly into the spaces between the stationary hearths, said stationary and rotatable hearths being so spaced as to define a confinecl sinuous passageway therebetWeen for material being fed therethrough, holloW rabbles attached to the lower sides s of said hearths and communicating there- With means for rotating said column, means for admitting heating gases to the interior of the lowermost stationary hearth, means .for causing said gases to pass' successively through each hearth and the rabbles associated therewith of the set, means for admitting heating gases to the lower end of the -therespective rotatable hearths for direotng said gases through openings in the walls of said column into the interior of each of said hearths in succession, means for scaling said sinuous passageway against ingress of heating gases or air, 'and means at progressive intervals in said retort for Withdrawing and separately collecting vapors eVolVed from material passing therethrough.

6. A retort for distilling carbonaceous materials, comprising a' casing, a plurality of superposed alternately disposed, holloW stationary and rotatable hearths so spaced as to define a confineol sinuous passageway therebetween for material being fed therethrough, means for supporting and rotating said rotatable hearths as a unit, consisting (of a holloW cylindrical column having openings therein communicating With the hollow interiors of said rotatable hearths, and

means for rota'ting said column, baflles in said column opposite the respective rotatable hearths and extending through said openngs into said hearths to direct gases' passing through 'said column into the holloW interiors of said hearths in succession, means for admitting heating gases to the lower end of said column, and means for withdrawng such gases from the upper end of said column after same have traversed successively said rotatable hearths.

7. A retort for distilling carbonaceous materials, comprising a casng, a plurality .of superposed alternately disposed hollow stationary and rotatable hearths so spaced as to define a confined sinuous passageway therebetween for material being fed therethrough, hollow rabbles depending from the lower sides of said hearths to substantially the upper surface of the next adjacent lower hearths, means for rotating said rotatable hearths as a unit, means for sealing said sinuous passageway against ingress of heating gases or air, an inlet fiue leading from a source of combustion gases and communicating With the lower end of said retort, a stack fiue leading from the upper end of said retort, means for dividing heating gases introduced through said inlet flue and for directing one portion `of same into the interier of the lowermost stationary hearth and then through the remaining stationary hearths and the rabbles assoeiated therewith in series, means for directing the remaining por- A In testimony Where I affix my signature.

WALTER EDWIN TRENT.

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