US3519540A - Carbonizing oven having parallel horizontal flues and u-shaped air ducts - Google Patents

Description

July 7, i970 M. D. CURRAN 3,519,540

CARBONIZING OVEN HAVING PARALLEL HORIZONTAL FLUES AND U-SHAPED AIR DUCTS Filed May 6. 1968 6 Sheets-Sheet 2 FIG. 3

INVENTOR MAURICE D. CURRAN ATTORNEY .uy 7 E? M. D. CURRAN 3,519,549

CARBONIZING OVEN HAVING PARALLEL HORIZONTAL FLUES AND U-SHAPED AIR DUCTS N m ,v Q LL.

Q QM Y INVENTOR MAURICE D. CURRAN BY wwjd ATTO RNEY uy 7, CARBONIZING ovLN HAVING PARALLEL HORIZONTAL FLUES AND U-SHAPED AIR DUCTS 6 Sheets-.Sheet 4 Filed May 6. 1968 RlmmlWHllwMA-l t..

L MAURICE D. CURRAN BY @LA fi @im 6 9 S Juiy 7, ff M. D. RRAN 3,519,540

' CARBONZING OVEN HAVING P LLEL HORIZONTAL FLUES AND U-SHAPED AIR DUCTS Filed May 6, 1968 6 Sheets-Sheet 5 i Si; i

\ GAS LINE m j AIR LINE 52 L iig-TURN cojvEvoR 53 k`\ INVENTOR I MAURICE D. CURRAN Bv @n ATTORNEY Juy 7, 1970 M. D. CURRAN CARBONIZING OVEN HAVING PARALLEL HORIZONTAL FLUES AND U-SHAPED AIR DUCTS 6 Sheets-Sheet 6 Filed May 6. 1968 :ll- IIIIIZII' INVENTOR' MAURICE D CURRAN ATTORNEY United States Patent O CARBONIZING OVEN HAVING PARALLEL HORIZONTAL FLUES AND U-SHAPED AIR DUCTS Maurice D. Curran, 916 Davis St., Garden City, Kans. 67846 Filed May 6, 1968, Ser. No. 726,751 Int. Cl. Cb l/06 U.S. Cl. 202-117 7 Claims ABSTRACT OF THE DISCLOSURE A carbonizing oven comprising a refractory chamber and a lower chamber, the floor of said refractory chamber being fabricated of material having heat transfer properties and a conveyor for pushing waste organic material along said refractory chamber floor for direct subjection to heat passing therethrough. Heat producing means are located `between said upper and lower chambers and consist of air ducts and combustion lines arranged in paired, vertically aligned relationship for extension transversely of the oven and with said ducts being suitably connected to exterior supplies of air and gas.

BACKGROUND AND SUMMA'RY OF THE INVENTION This invention relates in general to carbonization of waste and, more particularly, to an oven adapted for effecting such carbonization. Heretofore, such procedures as have been used for reducing carbon from Waste material have been consistently of batch character, requiring the subjection of a predetermined quantity of raw material to the particular sequence of treatment steps before the next batch is charged. Consequently, the production of such carbon has been relatively expensive and has as Well required utilization of rather complex equipment.

Therefore, it is an object of the present invention to provide a carbonizing oven which is adapted for continuois operation, thus, obviating the heretofore accepted batch operation and to be productive of substantial econ` omies is operation.

=It is a further object of the present invention to provide a carbonizing oven which incorporates means for moving raw material directly across a heat transfer surface as contradistinguished from systems involving the use of receptacle-type conveyors whereby the raw material is subjected to heat directed from above rather than below.

It is another object of the present invention to provide a. carbonizing oven which is uniquely adapted to utilize as a fuel gas produced as a by-product from the distillation of the raw material thereby further conducing to economy in operation.

It is a still further object of the present invention to provide a carbonizing oven of the type stated which requires the minimum in personnel for operation.

It is an further object of the present invention to provide an oven of the type stated which may be economically constructed; which is durable and reliable in usage; and the use of which will allow for the rapid, high volume, relatively cheap production of carbon.

BRI-EF DESCRIPTION OF THE DRAWINGS FIG. l is a top plan view of a carbonizing oven constructed in accordance with and embodying the present invention.

FIG. 2 is a fragmentary vertical transverse sectional view taken along the line 2 2 of FIG. 1.

FIG. 3 is a vertical transverse sectional view taken on the line 3 3 of FIG. l2.

FIG. 4 is a horizontal transverse sectional view taken on the line 4 -4 of FIG. 2.

FIG. 5 is a vertical transverse sectional view taken on the line 5 5 of FIG. 3.

FIG. 6 is a top plan view of the upper course of the conveyor.

FIG. 7 is a side view taken on the line 7 7 of FIG. 6.

FIG. 8 is a schematic vertical transverse sectional view taken substantially on the line 3 3 of FIG. 2 for illustrating the operation of the oven.

FIG. 9 is a vertical transverse sectional view taken substantially on the line 4 4 of FIG. 2 illustrating another flue arrangement constructed in accordance with and embodying the present invention.

FIG. l0 is a vertical transverse sectional view taken substantially on the line 5 5 of FIG. 3 but illustrating the flue arrangement shown in FIG. 9.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now by reference characters to the drawings which illustrate the preferred embodiment of the present invention. A generally designates a carbonizing oven, as indicated in FIG. l, which is of substantial elongate character incorporating a framework, as at F, of I-beams and like structural components for maintaining the integrity of oven A by buttressing the side walls S, s thereof, said latter being desirably basically of brick. Oven A and framework F are supported upon a concrete foundation C; there being preferably several layers of Ventilating bricks 1 between said foundation C and base wall 2 of oven A. Supported upon the upper ends of side walls s, s is a top wall 3 which may be of concrete, brick, or combinations of the same. Extending substantially the length of oven A are lower and upper vertically spacedapart tunnel- like chambers 4, 5 respectively; the ends of said chambers terminating in immediately spaced relationship to oven end walls, as indicated at 6 (FIG. 7) and 7 (FIG. 2). Upper chamber 5 is of refractory character comprising an upper arch wall 8, parallel side walls 9, 10, which are integrated with the adjacent oven side walls s, s', respectively, and a floor 11; which components are continuous throughout their length thereby leaving chamber 5 open at its extreme ends. Floor 11 is fabricated, by choice, of silica brick for conducing to heat transfer, while side Walls 9, 10 are formed of lire brick and arch wall 8 is preferably of fire clay.

Lower chamber 4 is of generally like design as upper chamber 5 and comprises an upper arch wall 12 located spacedly downwardly of floor 11, side walls 13, 14, as constructed preferably of brick, with the iloor of said chamber being constituted of oven base Wall 2. As is evident from FIG. 3, chambers 4, 5 may be of substantially like dimensions and volume.

Mounted within oven A proximate each end 6, 7 immediately beyond the ends of chambers 4, 5 and disposed for rotation about an axis extending transversely between side walls s, s are transversely aligned paired sprocket wheels 15, 15', 16, 16', respectively. Sprocket wheels 15, 15' are mounted upon a shaft 17 projecting through suitable apertures in side walls s, s' for journaling within bearings 18, 18 provided externally of said side walls. Shaft 17 extends beyond bearing 18 for operative connection to a gear reducer 19 which is suitably connected to a prime mover 20. Sprocket wheels 16, 16 are mounted upon an idler shaft 21 which, at its ends, projects through openings in side walls s, s' for journaling within exteriorly provided bearings 22, 22'. Trained about sprocket Wheels 15, 16 and 15', 16 are the chains 23, 23', respectively, of an endless conveyor, designated generally E; there being push bars 24 extending transversely between said chains 23, 23 at spaced intervals throughout the entire extent thereof; said push bars 24 being preferably, but not necessarily, of angle shape having a vertical leg 25 and a relatively shallow horizontal leg 26, which latter, on their under surface, will travel contactingly across the upper face of floor 11 of upper chamber 5. Thus, as is indicated in FIGS. 2 and 7, the upper course `of conveyor E travels through upper charnber 5 in a direction toward end Wall 7 so that said upper course may be considered the load conveyor, while the lower course of conveyor E moves through lower chamber 4 on steel rails in a direction toward end wall 6 with such course being considered the return conveyor. Thus, push bars 24 are mutually spaced for impelling material, of the type to be described hereinbelow, through upper chamber 5 by travel across floor 11.

As indicated in FIG. 7, oven A is provided with a suitable opening 27 in top wall 3 proximate end wall 6 for charging raw material to the upper course of conveyor E. Continuous with floor 11 at its end proximate end wall 7 (see FIG. 2) is a downwardly directed chutelike guide 28 for directing the now-treated material for delivery by gravity to a hopper 29 located therebelow; there being associated with said hopper a conventional screw conveyor, as broadly indicated at 30, for removal of the treated material to a suitable collection point beyond oven A. Above hopper 29 there is presented a pipe 31 connected to a suitable source of Water for directing quenching water into said hopper 29 for cooling the heated materials. In view of the foregoing, it will thus be seen that oven A is uniquely adapted for continuous operation whereby raw material charged to conveyor E at one end of oven A is suitably treated by a single pass through upper chamber 5 and with the treated material being effectively discharged as promptly as delivered. Accordingly, oven A o'bviates the heretofore time-consuming, costly batch operations as accepted in carbonizing procedures.

Provided above arch wall 12 of lower chamber 4 is a partition 32, as of fire brick, extending transversely between sides s, s'. Upon the upper surface of partition 32 is disposed a multiplicity of ducts 33 which are spacedapart longitudinally of oven A and extend transversely between sides s, s. Said ducts 33 are similarly formed of re brick or like material. Provided above ducts 32 is a series of combustion ilues 34, being similarly spaced-apart longitudinally of oven A for extension transversely thereof. Said fiues 34 are defined by structural portions formed of silica or the like and with the upper component of said ues 34 being constituted by floor 11 of upper chamber 5 for ready heat movement therethrough from the cornbustion within said llues 34. Ducts 33 are closed at one of their ends, as by wall s or s as the case may be, and at their opposite ends are in communication with air inlet pipes 35 extending through an opening 36 formed in the associated side wall s, s. Air inlet pipes 35, outwardly of the adjacent wall of oven A, are connected through a manifold 37 which, in turn, communicates through an air supply pipe 38 with a convenient air supply, as indicated at 39 in FIG. 8.

Referring now to FIG. 4, it will be observed that the air inlet pipes 35 are arranged in groups or banks, as suggested at 40 in FIG. 1, which are located upon opposite sides of oven A and, thus, are staggered or alternated throughout the length thereof. It is to be recognized that the number of air inlet pipes in any one bank may be determined by consideration of numerous, obvious factors.

Each flue 34, at One of its ends, is closed, as by wall s or s', and at its other end is continuous with a gas inlet pipe 41, which is securely received within opening 42 formed in the related side wall s, s', as the case may be. At their outer ends, gas inlet pipes 41 are connected to a manifold 43. In turn, the gas manifolds 43 are connected to a gas supply pipe 44 (FIG. 8) Which leads from a convenient gas supply, designated 45. Referring to FIG. 4, it will be seen that gas inlet pipes 41 are arranged in groups or banks which, perforce, correspond in number to the air inlet pipes 5 co-ordinating therewith. Said banks or groups of said gas inlet pipes 41 are indicated at 46 in FIG. l and, thus, said banks or groups will alternate or be staggered throughout the length of oven A. As may be apparent from FIG. 4, the number of gas inlet pipes 41 in any one bank, and the number of air inlet pipes in any one bank, are shown as being nine in number since each air duct 33 will be in paired, co-ordinated relationship with a gas flue 34. It is also apparent that gas and air pipes 41, 35 respectively, are provided with orifice control plates, as indicated generally at 47, 48, respectively, for controlling the relative amounts of gas and air in each flue 34.

Each air duct 33 in its end portion remote from its related inlet pipe 35 and in its upper wall, is provided with a port 49 which is located in immediate proximate relationship to the inner end of the related gas inlet pipe 41 for effecting combustion, with heat being developed throughout ue 34 for transfer through oor 11 for treatment of the raw material being conveyed therethrough by conveyor E. Flues 34, in their end portions remote from the respective gas inlet pipe 41, are in communication with a passage 50 through partition 32 for communicating with the volume between the latter and the upper surface of arch Wall 12 of lower chamber 4, such volume or compartment being indicated at 51. Provided along the side of volume 51, beneath each bank of gas inlet pipes 46, is the upper end of a plurality of ducts 52 which extend outwardly of the related Wall for communication at its other end with a waste gas flue 53 which may be incorpOrated in foundation C.

Arch wall 8 of upper chamber 5 is provided spacedly along its length, and substantially transversely thereof, with a plurality of openings 54 for receiving ttingly therein the lower ends of upstanding collector pipes 55; the upper ends of the latter project through openings 56 in top wall 3 for extension thereabove, as at 57. Said collector pipes 55, at their upper ends, are continuous with a horizontal conduit 58 for communication through the latter with an elongate gas collecting main or trap 59. Trap 59 is connected to a gas purifier or scrubber 60 (FIG. 8) wherein gas within the gaseous waste from matter being treated in chamber 5 is separated from water and other inpurities therein entrained so that the gas emitted from scrubber 60 may be directed to gas supply 45 by a gas exhauster for ultimate usage as fuel within the combustion system of oven A.

Oven A is especially designed for carbonizing organic waste matter, such as, for instance, wood, vegetable matter, and the like. Such matter may be obtained from any source of refuse, as, for instance, a city dump, but it is understood that all metallic, ceramic, glass, and rubber will be separated prior to charging of the raw material to oven A. Such raw material is thus directed upon oor 11 of chamber 5, at the proximate end wall 6, for travel therealong through operation of the push-bar conveyor E as above described. Said raw material is thus in immediate Contact with the heat transfer surface deiined by oor 11 through which, as above described, heat is passing from combustion ues 34. It is to be observed that air being directed from air supply 39 to air inlet pipes 35 is not pre-heated but is at a slight controlled pressure, such as in the order of 2 mm. of Water pressure as required to provide a balanced pressure in ilues 34. During travel of air through ducts 33 toward port 49, preheating will occur by reason of transfer from ilues 34. The temperature developed within combustion tlues 34 is appropiately controlled to be within the range of about 1000-l400 F. for effectively carbonizing the organic raw material. Obviously, oven A is adapted t0 operate at a temperature below that wherein push bars 24 of conveyor E would tend to weaken.

The products of distillation in gaseous form, from the carbonizing of the raw material, will be directed upwardly through collector pipes 55 for ultimate separation in scrubber 60. Thus, the by-products of the raw material will enhance the economy of operation of oven A by constituting a continuing source of fuel. As described above, the treated raw material, which is now carbon, will be deposited in hopper 29 for any further treatment as might be indicated, such as, for instance, for the production of activated carbon, for the manufacture of briquettes for fuel purposes etc.

Any waste fuel gas within lower chamber 4 may be dissipated to the atmosphere through a conventional chimney (not shown).

Referring now to FIGS. '9 and l0, there is illustrated another system of gas and -air provision for oven A. Immediately provided above partition 32 is a plurality of generally U-shaped air ducts 61 each having a pair of legs 62, 63 in axially parallel relationship, extending transrversely of oven A and being connected at one of their ends by -a short section 64. Each leg -62 of each duct 61, is connected at its end opposite section 64 to an air inlet pipe 65, which latter is suitably fixed within an opening 66 in wall s of oven A. Each of said pipes 65 communicate at their outer ends with a continuous air manifold 67 located immediately outwardly of wall s and extending therealong. Each leg 63 of each duct 61 is closed, as by wall s', at its end remote from section 64, but in its upper surface is provided wtih a plurality of ports 68 located spacedly lengthwise thereof. The ports 68 of each leg 63 of each duct 61 communicate with the interior of an overlying gas flue or combustion chamber 69 so that by said port 68 air is fed into the related gas flue 69 throughout substantially the length thereof as distinguished from the single air providing source 49 as described hereinabove. Each liue 69 is closed at one of its ends by wall s and at its other end communicates with gas inlet pipe 70 secured within an opening 71 in side wall s and connected at its end beyond said side wall s to a gas manifold 72 extending along oven wall s in axially parallel relationship to air manifold 67 and spacedly thereabove. With this arrangement it will thus be seen that the air and gas manifolds 67 and 72, respectively, are located on the same side of oven A thereby distinguishing from the staggered bank arrangement hereinabove described. Such arrangement is productive of obvious economies in production as well as promoting enhancing combustion within flues 34 by facilitating flame propagation.

As shown in FIG. 9 waste gas flue ducts 73 are located spacedly along wall s of oven A, that is, on the side opposite manifolds 67, l72 and thereby overcoming the difficulties required with the staggered arrangement herein above set forth.

It should be understood that changes and modifications in the formation, construction, and arrangement and combination of the several parts of the carbonizing oven lmay be made and substituted for these herein shown and described without departing from the nature land iprinciple of my invention.

Having thus described my invention, what I claim and desire to obtain by Letters Patent is:

1. A carbonizing oven comprising means defining upper and lower elongated chambers, said upper chamber having -a floor formed of material having heat transfer properties, means for charging raw material upon said upper cham- -ber floor, means for moving said raw material directly upon, and along, said floor, a source of heat provided below said floor for transfer therethrough to effect carbonizing of the said raw material, said source of heat comprising a plurality of air ducts extending transversely of said oven, means defining a plurality of combustion flues above said air ducts, la source of gas, means connecting said source of gas to said combustion flues, a source of air, means connecting said source of air with said air ducts, each air duct being of U-shaped formation having first and second axially parallel legs extending transversely of said oven, there being a short connecting section extending longitudinally of said oven, said second leg having a plurality of openings for commuication with the overlying combustion flue.

2. A carbonizing oven as defined in claim 1 and further characterized by gas purifying means located exteriorly of said oven, and means connecting the interior of said upper chamber and said gas purifying means, and gas pres sure regulating means to maintain a `balanced pressure within the carbonizing oven by regulators which control the operation of the gas exhauster.

3. A carbonizing oven as defined in claim 1 and further characterized by said combustion flues being in axially parallel relationship with said air ducts and the number of said combustion flues corresponding in number to said air ducts.

4. A carbonizing oven as defined in claim 3 and further characterized by said means connecting said source of gas to said combustion flues comprising means defining a gas inlet opening into each of said combustion ues at one end thereof, means defining 'a gas manifold connected to a pre-determined number of said gas inlets, and means connecting said manifold to said source of gas, said means connecting said source of air t0 said air ducts comprising means defining an air inlet opening into each air duct at one end thereof, air manifold means in connection with a pre-determined number of said air inlets and means connecting said manifold with said source of air.

5. A carbonizing oven as defined in claim 4 and further characterized by said air inlets and said gas inlets being located on the same side of said oven, and said means for moving said raw material comprising an endless conveyor for travel through said upper and lower chambers, rotating means provided at opposite ends of said oven about which said endless conveyor is trained, whereby the upper course of said conveyor will pass through said upper chamber and the lower course of said conveyor will pass readily through the lower chamber, means ifor driving said conveyor, said conveyor having a plurality of bar members presented for extension transversely of said chambers and being spaced apart longitudinally of said conveyor, said bar members being disposed for contactive engagement with the floor of said upper chamber during its travel therethrough for maintenance of the raw material in heat transfer relationship with respect to said chamber floor.

`6. A carbonizing oven as defined in claim 4 and further characterized by said air inlets and said gas inlets being located on the same side of said oven, and exhaust ducts located on the other side of said oven being in communication with said combustion fiues for exhausting expended gases.

7. A carbonizing oven as defined in claim 1 and further characterized by said second leg openings being axially aligned and disposed spacedly lengthwise within said combustion flue for supplying air to said combustion flue substantially throughout its length.

References Cited UNITED STATES PATENTS 1,591,023 7/1926 Ditto et al. 202-117 XR 1,493,758 5/1924 Lamie 202-117 XR 2,598,931 6/1952 Narsted 34-236 XR 2,812,291 11/1957 Hughes 202-101 WILBUR L. BASCOMB, JR., Primary Examiner D. EDWARDS, Assistant Examiner U.S. Cl. X.R.

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