US1704093A - Frederick deacon marshall - Google Patents

Description

March 5,1929. F. D. MARSHALL 1,704,093

APPARATUS FOR PRODUCING COKE AND GAS FROM SOLID CARBONACEOUS MATERIAL Original Filed April 10, 1926 5 Sheets-Sheet March 5, 1929.

F. D. MARSHALL ,093

APPARATUS FOR PRODUCING COKE AND GAS FROM SOLID CARBONACEOUS MATERIAL Original Filed April 10, 1926 3 Sheets-Sheet p i; /0 /0a /a f /w&

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ATTORN EY March 5, 19 .9- F. D. MARSHALL. 1,704,093

APPARATUS FOR PRODUCING COKE AND GAS FROM SOLID CARBONACEOUS MATERIAL Original Filed April 10, 1926 s Sheets-Sheet INVENTOR ATTORNEY Patent ed Mar. 5, 1929.

ater I UNITED stars-s mm? c erics.

FREDERICK BEACON MARSHALL, 'OF WEYBRIDGE, ENGLAND.

, nrPAsAr s roa rnonncme COKE AND GAS rnorrsoLrD cannormcnous MATERIAL.

Application filed April 10, 1926, Serial No. 101,072, and in Great Britain June 5, 1925. Renewed December This invention relates to' apparatus for simultaneous I manufacture of carbonaceous I gas and coke. The main object of this invention is the production of carbonaceous gas from material which also produces coke, as the result of the distillation and carbonization of the material with which the apparatus is charged. Y

In the accompanying drawings illustrating the principle ofthis invention in the best mode now known to me of applying that principle,

Fig. 1 is a vertical, central section of the retort structure at line 1-1 of Fig. 3 showing a pair of top feed screws in elevation and illustrating by arrows the direction of fuel under carloonization and by other arrows the upward ascent of gas. The view also shows coke in the process of discharge from the under end of the retort; 5

Fig. Q-is'a transverse section 'of'the upper feeding casing structure at line22 of Fig. 1 and .showsthe feed casing with a charge of carbonaceous material, such as bituminous coal. within the casing.

Fig. 3 is a transverse section through the retortcasing-proper and shows the relations of the cells for containing material to be cari bonized, to the gas tubes or ducts.

Figs. 4 and 5 illustrate another form of the invention, Fig. ibeing a verticalcentral section of-the retort structure at line 44: of Fig. 7 and ,Fig. 5 being a vertical central section at line 5 ,5 of Fig. 4. j i

Fig. 6 is a transverse section of feed casing and with charge inp'lace, at line 66 of Fig. 4; and

Fig. 7'is'atransverse section of the retort at line 7,7 of Fig. 4. a Fig. 8 illustrates another form ofcellular retort casing proper construction and wherein' material to be carbonized is shown in ducts areshown.

Fig. 9 is a crosssection at line 9-9 of Fig.

1 and shows the location of the gas outlets at the upper end portions of the gas tubes...

Fig. 10' is a vertical, central section .ofthe place in vertical cells and wherein also gas I shaft supporting glan'd'structure with a feed screw shaft partially shown. Fig. 111s'a crossssection of what is shown.

in Fig. 10 at line 11'11 of Fig.10. in

Figs.. 12,. .13. and 14 are viewsof a screw shaft reduclng gear.

the upper I In the accompanying drawings, 1 is the retort casing proper wherein the material to be gasified and coked is contained. 2 is the head casing; 2" are a pair of noncontac ting feed screws which may either overlap or receive the peripheries of the helices just clearing each other; 3 are the gas ducts-shown as connected by cross webs 00 to the inner sides of the retort casing. It will be noted that these ducts have gas escape openings at their upper end portions. Their tops are closed, but they are open at their under ends. The charge receiving cells 3' are open both at top and bot.- tom. The cell walls are indicated by 3*. All the duct or passageway walls are connected by webs a. The retort casing 1 is enclosed by a spaced apart combustion or heating chamber wall 3 I To preventcoal or other material passing down the gas ducts, the open topof each is fitted with a cover or stopper S above the gas duct escape slots 5.

4 is the expansion joint shownin this 13215;

at the bottom end of the retort casin and is filledwith a suitable packing 4 5 is the coke receptacle which formsthe framework of balanced flap doors 6 shown attached to a rocker shaft 6 the ends of which are pro? vided with counter weights 7 for closing and maintaining the doors in a closed position. 8 are the twin screw shafts;'9 is the gas outlet 10 is theinlet for material under course of treatment; 11 are gas-tight supporting glands from which the screws depend.

121is the turning gear which has been specially designed for the present purpose and which is connectible with an electric m0- torM by which a motorspeed of 1000 revolutions per minute is reduced by means. of the arrangement to give the feed screws a roscrew propellers aresituated in the separate head casing .or upper section Q'which is attached to the upper end of the retort casing proper or lower section 1 which latter casing may be heated if desired by the described method of my copending application Ser. No. 101,07iiled April 10, 126, for the pur pose of carbonizing, gasitying and coking the material passing through the retort. The casing 2 containing the screws is situated outside the zone of heat. The short screws in the upper, non-heated casing 2 act as collectors of the material and propellers ot the same to force the material which is fed by these screws or propellers downwards into through vertical ducts of the heated body of the retortcasing or lower section 1, where the material undergoes carbonization or gasilication. Said lower section 1 is the heatable, coal distillation structure of the apparatus.

The experience has been gained by the in 'ventor to effect low temperature carbonization at a temperature ranging between 900 1200 Fah. that, the thickness of the material under the process of carbonization or gasification must not exceed tour and one-halt inches and that provision must be made for applying this heat to all tour sides of the material. As the density of the resultant coke from the material-is entirely due not to temperature but to the expansion of the material wliile'in a semi-carbonized or semi-plastic condition and as this expansion exerts a great force,

provision must be madethat the walls of the duct-s through which the material is forced by the pressure, and also the screws are of sufficientstrength to withstand the great pressure.

The bore of theupper, headcasing 2 and of the lower carbonizing section is practically the 'saine, and when both are seen empty they will represent a true bore from end to end of both sections when fitted together.

inches in cross-sectional dimension.

inch per hour and practically and commercially considered, it is highly desirable that the cross-section ot the ducts shouldnot be over about four and one-halt inchesalong the intermediate portions of theducts, where the active distillation of the coal takes place, adjacent and above the lower portions of the ducts where the coking progressively effected. p

These radial and transverse webs are an integral part of the retort casing itself, being cast as part of the same; and by reason of the conductivity of cast iron and by molecular ailinity ot' the iron, the heat applied to the exterior of the retort is conducted through all the tranverse and radially disposed members and is so imparted to the material which fills the retort cells or ducts during its-passage through the same.

The said cells or ducts need not necessarily be of the same cross-sectional area or shape as they may be so shaped as to produce slabs of coke, bearingalways in inindthe four and one-half inches condition or they may be disposed (Fig. 8) inhoneycomb form for the purpose otproducing a briquette like form-0t v The said members or walls t'orinin g the cells or ducts are located between the outer casing and inner hollow gas ducts tor aiding the rapid withdrawal of the evolved gases from the retort, and have nothing to do with the heating of the same.

During the evolution of the gases, the gas outlet is under the influence ot minus atmospheric pressure owing to the action of the gas exhauster, not shown, but diagrammatically indicated. v v v l The evolved gases find their way to their outlet through the centres of the char es of material as, owingto the pressure exerted on all sides by the expansion of the charges during carboni'zation, very little or no gas can find its way up between the outer sides of the charges and the inner surfaces of the containing cells or ducts. V

The coal and gas ducts being open at each end are naturallysusceptible to the eX'hauster suction on the interior of the retort generally, and as the evolved gases seek toleave, the centres of the charges by the path otl ei ing the leastresistance, it open for these gases to leave partly direct through the upper portion of the charges'or partly through the lower ends of the gasducts, andthe arrows in the drawii'ig show the approximate paths the gases take. The coal or distillation ducts are open at their upper and under ends. The gas-ducts are open at their un= der ends, and though closed at their upper end openings by members S inorder to prevent the coal vfrom being TEOl'CGtl down into them and so cloggii'ig theducts, are provided at their upper end portionsadjacent the members S with gas escape portssf Much value is attached to these ducts "as the easier and with less resistance the gasescan escape, the chances of their being cracked or split up is greatly lessened.

To increase the throughputcapacity'of the retort, the divisions or webs in the: retort may be disposed in an annular manner and, provided all divisions "are connected physi cally with the. inner wall of the retort, the

carboniza'tion of the interior columns of ma destructive consequences.

eject the charge of carbonized coke from the casing automatically andcontinuously before the pressure on the material leads to According to the present form of my invention, this is efi'ected by the installation, atthe lower end oi the lower casing or sec- .tion 1 of a coke boxor receptacle within which a pair ot-flap doors d are installed working on hinges; and which, when. in a horizontal condition, close the bottom of the superimposed casing in a practically gas.

tight manner as the edges of the flaps are bevelled to the same angle as the. tapering sides of the coke box or receptacle against .which they contact, so that the foot oft-he columns of coke in the casin rest on the flaps which are kept in position by a lever attached to each flap which levers are controlledby weights or springs. l

The desired pressure tobe exerted by the;

' 'co-acting serewson the charge of material,

totorce-the same throu hthelower casin having been ascertained, the levers are weighted accordingly so that when the pressure on the charge reaches a certain point the flaps are forced open and a portion of the chargein the form of coke is ejected into the gas-tight box or receptacle below the. flaps. When the pressure is relieved, the weight on the levers causes the flaps to return to a horizontal position. Y

At intervals the coke receptacle isopenec and the coke removed during which period therevoliition of the co-acting screws may be stopped and t he fiapsheld up to 'cnsure against the enteringfof air into the retort casing. v

The-design of the flap doors 6. may be varied and instead of hinging t 1cm on their long sides they may be. hinged on their short sidesin either case being controlled by the outside levers fitted-with either weights" or springs. The flap doors Gare merely one form of coke escape control apparatus for also offering a resistance to the downward feeding pressure and; load of the coal in its inltlal condition, in its active d1st1llat1on and gas evolving condition,and in its progressive coking .inthe lower portion of cachdis tillation .duct.

The. density of. the coke can, be"varied' by the, amount of pressure 1t 1s sub ectedto during its formation in the retorta'nd this controllable variation ot pressure is another feature of-my invention. j I I p V To take up the expansion of the retort in a vertically, longitudinal direction, it pro? outwardly ot-the receiver.

7 11 is applied. The casing has a bottom that is solid except for a central shaft opening through which a shaft 8 extends upwardly through the fixed cover plate 13 of easing 2, and upwardly through the fixed cover it of casing 11 for reception of members of the turning gear 12. I Within the gland'casing, there is'at its bottom portion a pair of discshaped ball races 15 between which anti-triction balls 16 are located, the shaft passing through the races and upwardly through a piston 17 provided with piston rings 18. The piston is pinned to the shaft by pins 19 and has a length less than the distance between the upper race 18 and the gland casing cover, leaving a clear space 20 into which the piston may ascend on elongation of the shaft due to heat. Each screw is suspended from its piston which normally rests on the upper race. Thebottom of the gland casing is provided with a packing '3 around the screw shaft and the gland as a whole is gas-tight and constitutes a gas-tight, anti-friction screw suspending mechanism that permits endwise movement of the suspended screw. 7 The turning gear or driving mechanism which .is fixed on the upper casing cover, although it may be otherwise supported, includes an addition to the gear 12 which is a spur gear, one on the upper end oteach screw shaft, an intermediate spur gear 21 in mesh with gears 12. Norm gear 22 is mounted on the upper end portion of a vertical stub shaft 23 and efl'ects rotation of the screw shafts simultaneously in the same direction. Vorm gear 22 is in mesh with worm 25 on a horizontal shaft 26 which is provided with a worm gear 27. 1 This worm gear 27 is in mesh with an intermediate worm 28 on a shaft 2 also of about 1000 revolutions per minute to a screw rotational speed of from six to ten revolutions per hour, as above stated.

The stoppers S at the upper ends of the tubes'are fixed in place, thus preventing entrance of the material into tne gas tubes or passageways; but the gas exits ports 8 are con tinuously open so that the. generated gas may continuously escape therethrough, into the communicating space S and then to the exit 9, while the retorting operation is active.

The rocker shaft 6 mounted in openings of the wall ot the receiver '5 for cokeor other reid'ue ofdintillation, extends at both ends Each end has a dependent arm 6* for reception of one or more removable weights 7, two of which are shown lit) s on each arm. The weights maybe increased or diminished in number according to the character of the material to be treated. "Receiver 5 is practically air-tight and is provided with an opening 5 through which the residue of? distillation may be removed from lime to time. Each opening is shown provided with a door 5.

The combustion chamber 3 is for heat applied during the rotor-ting operation which may be a 'low temperature operation for which the apparatus is especially intended.

The intake is provided, in practice, with a gas-tight charging device 1O any desired constructitui, the charging device is herein indicated diagraniniatically.

In operation, succeeding initial charging, charge arresting and carbonization, the feed screws may be driven continuously and the charge arresting doors may be continuously opened for either partial momentary interruption in escape, or, forcontinuous escape, of the coke into the coke box. with the box door closed to prevent inrush of air, all de- Evolution and removal of the gas is con-' tinuous. The cl'iarging operation maybe continuous or intermittent depending on the type of charging apparatus used. The dis harge of the coke into the coke boxis automatically intermittent.

in Fig.5. 5, the as escape 9 is shown dischar 7 5 into a diagrammatically illustrated exhauster 9. The cxhauster connection is su'tlicient in practice to ell ect the ascentof gas into the escape 9,'notwithstanding the pressure on the charge between the feed screws r and flap doors. .SOEHQ of the ascending gas and for forcing the escapes from fissures in the col-1e and some of it from material M there-above;

The coal ducts ret'crred to may be properly designated distillation ducts. The under helices or the feed scre vs are effective to force and break up said material against the upper ends 01 the uistillation duct walls n'iaterial downwardly into and through the ducts. .Vhen the coal -:l.ucts are filled andthe feed screws are in action, the coal or other material. is forced into the upper, open ends of the coal ducts. and is under 5-;UTQ- l()\\11W2l]JtllY to the echo 4 control apparatus. d hile this A crmits, by vibration of the tree yes oi the flap doors on which tie coke initially rests, continuous escape of the coke according to adjustments of the weights 7, the apparatus, nevertheless, otters such a resistance to the downward pressure that the pressure densities the coke substantially andfirmcoke is produced. It will be observed that the heatable, metal wallsot the coal and gas ducts are integral and serve to conductcxteriorly applied heat-to and through the material in the coal ducts; and that there is a plurality of coal ducts subjacent the under end of each feed screw. The integrally and metallically walled, coal ducts are raised to a temperature sufficient to render portions of the coal, as it is forced compressively downward from the upper end portion of the coal ducts, plastic; and in this condition gas is freely evolved, the plastic condition permitting the feed screw pressures to condense and solidity I the coke formed in the lower portion of the coal ducts against the flap doors or gates carried by the adjustable, weighted rocker shafts 6 When the apparatus is in operation these flap doors or gates are never closed,'butare constantly vibrating and thus permit continuous discharge of the solidified or densilicd coke which, withall the superincumbentmaterial in the coal ducts, is under continuous downward pressure by the feed screws. .The

teed screws and their operating mechanism constitute, in effect, a continuously operable means-tor feeding and also t'orcing'the coal or other gasifiable and coke producing material into and through the distillation ducts and compressing thecoke into an extremely firm, dense coke against the resistance offered by the coke control discharge means operable to form a resistance to the compressive densi fication of the coking, plastic material thereabove. The feed screws are spiral screws of the same hand and are shown of the same pitch. The cross section of each screw is that of a spiral screw. The screw helix of reach screw extends from an intermediate keeping the in-t'ed coal and the coking plastic stratum or strata under constant pressure as described, the formation of thin and fragile walled coke cells is prevented and a dense compact coke product obtained. Such a densitication is of very great importance to the coke product as it does not break up or give oii' coke dust as is the case with coarsely' cellular coke, Moreover, theconsta'ntcompression is favorable to evolution of the evolving from the coking portion of the'coal and from the coal.

WhatI claim is i 1. In apparatus for simultaneous production of gas and coke from carbonaceous material, the combination of an upright casing having an upper and a lower section; said upper section being provided with a preliminary coal charging apparatus, and means to effect escape oi ascending gas .or gaseous vapor, and being open at its under end for dis charge of the material under feed screw pressure; and, apluralityot adjacent vertical, downwardly feeding, spiral feed screws of the same hand within said upper section of the casing; said lower section of the casing being of metal and being provided with a plurality of vertical, metal distillation duct walls having their upper ends opposed to and spaced apart from the under end of each of said feed screws, each feed screw having a cross section dimensioned to cover a plurality of the upper ends of the ducts, and the distillation ducts being open at their lower ends above the bottom wall of the lower section of the casing, for escape of gas and coke; mechanism for removing the coke;

- mechanism for rotating said feed screws; a

combustion chamber around the distillation duct wallspeach of said feed screws being efiective to force said material into the upper ends thereof and for forcing the material downwardly into and through the ducts; the duct walls conducting heat received by them to the carbonaceous material in the ducts; and gas oil -take ducts extending upwardly from the lower portion of the under section.

2. In apparatus ofthe class described, the combination of a plurality of upright, continuously revoluble, spiral feed screws of the same hand mounted within a casing and arranged to deliver and to force material continuously downwardly into the upper open ends of a series of integrally and metal walled elongated, upright ducts of small cross section relatively to that of the casing above the ducts, and through and out of said ducts; each feed screw being dimensioned to cover a plurality of the upper ends of the ducts; and upright metal structure provided with said ducts, means for eXteriorly heating said metal structure to render plastic therein descending portions of the material for evolution of gas and production of coke in lower portions of said ducts; and continuously operable, coke discharge control mechanism'efiective to ofier resistance to the pressure produced by the downward feed of the material; and means for conducting the generated gas upwardly and out of the apparatus; said feed screws having their under ends adjacent, but spaced apart from, the upper open ends of said ducts; and said integrally and metal walled ducts being arranged in parallel. groups wherein each group comprises a plurality of ducts subjaoent the under end of each :teed screw.

3. In coal gas and compressed coke making apparatus, the combination of a continuously operable, coal feeding mechanism, said mechanism including a casing and spiral teed screws mounted therein; a coke discharge control mechanism; and, interposed between said feed screws and said coke discharge control mechanism, an elongated, metal distillation structure having a plurality of sets of 0pen-ended, lengthwise extending, distillation ducts grouped in each set around and enclosing a gas escape duct, the ducts in each set of distillation ducts being opposed to one of said feed screws, each feed screw being dimensioned to cover the upper ends of a plurality of said ducts; the walls of all the ducts being integral, and each feeding mechanism being operable not only to feed into adjacent open ends of said distillation ducts, but also to force the material fed compressively into and to fill the same, to compress therein formed coke against the resistance of the coke discharge control mechanism when the same is in coke arresting position, and past the same when it is in position for discharge of coke; said coke escape control mechanism being operable to arrest and resist the escape of coke against the pressure of said coal feeding mechanisms and also permit the discharge of the coke; and means for exteriorly heating said structure; the ends of the gas escape ducts adjacent the coal feeding mechanisms being closed to prevent iii-feed of coal and adj acently provided with gas escape ports; and the ends of said gas escape ducts adjacent the coke discharge control mechanism being open for intake of gas.

Signed at New York city, in the county oi New York and State of New York, this 12th day of March A. D. 1926.

FREDERICK DEACON MARSHALL.

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