|Publication number||US3449211 A|
|Publication date||Jun 10, 1969|
|Filing date||Apr 28, 1967|
|Priority date||Apr 28, 1967|
|Publication number||US 3449211 A, US 3449211A, US-A-3449211, US3449211 A, US3449211A|
|Inventors||Giacomo Angelo A Di, Gorand Alfred J|
|Original Assignee||Sun Oil Co|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (7), Referenced by (3), Classifications (17)|
|External Links: USPTO, USPTO Assignment, Espacenet|
June 10, 1969 A. J. GORAND ETAL APPARATUS FOR PYROLYSIS OF SOLIDS Sheet Filed April 28, 1967 on. BEARING SAND HOT REGENERATED SAND INLET 24 TO REGENERATOR 53;}
INVENTORS ALFRED J. GORAND y ANGELO lyl GIACOMO /TTORNEY June 10, 1969 APPARATUS FOR PYROLYSIS Filed April 28, 1967 FLUE GAS OUT FROM REACTOR I FIG. IA J 6| 0 I I f I I 61 OQQ\ 49 S Q 0 O 50 AIR IN 59 TO WASTE STORAGE FIG. IB
A. J. GORAND ETAL OF SOLIDS Sheet 3 of 2 HOPPER l Iz TO HOT SAND INLET 9 0N REACTOR I FIG. IA
INVENTORS ALFRED J. GORAND BY ANGELO A. DIGIACOMO EMMA? TTORNEY United States Patent US. Cl. 196120 5 Claims ABSTRACT OF THE DISCLOSURE Fresh particulate solid material containing volatilizable constituents is physically mixed with hot particulate solid material at one end of a closed elongate vessel, the mixture then being moved to the opposite end of the vessel on a flat belt. During the travel through the vessel, the relatively cool fresh material is heated by the hot material and is pyrolyzed to drive off its volatilizable constituents. As a result of the pyrolysis, a combustible deposit is left on the pyrolyzed material. The solid material is abstracted from the far end of the vessel and the combustible deposit is burned off in a separate regenerator, this burning heating the material to a high temperature. A portion of this latter material is recycled to the vessel to serve as the hot material for the pyrolysis of the fresh incoming material.
The present invention relates to apparatus for the pyrolysis of solids containing volatilizable constituents. More particularly, the invention is concerned with an improved apparatus -for the distillation of carbonizable solids such as various oil-bearing minerals including oil sands (tar sands), oil shale, coals, lignite, cellulosic materials, and the like.
Broadly, the process carried out in the apparatus of the invention is similar to that disclosed in the prior copending Bennett application, Ser. No. 546,225, filed Apr. 29, 1966. Process-wise, the raw material such as oil sand which is to be treated or processed is heated in a retorting vessel to drive off volatilizable constituents, the evolved gases escaping from the vessel through a gas collecting system as valuable gaseous products (vapors).
The apparatus of the present invention, like that of the aforementioned copending application, utilizes, for the retorting or distillation or pyrolysis, a heat exchange between two solids which are in direct and intimate thermal contact with each other, rather than a heat exchange between a solid and a gas. That is to say, the solid raw material which is to be retorted or distilled or pyrolyzed is heated by directly contacting the same with a hot solid material.
In accordance with the present invention, the processing (i.e., the retorting or pyrolysis) of the solid material to be treated takes place in an elongate horizontally-disposed vessel which is preferably of cylindrical configuration. The material to be treated, in traveling from the first or entrance end of the vessel to the other or exit end thereof, passes through three zones in succession, first a feed zone, then a mixing zone, and finally a reaction zone. Each zone is defined by a separate horizontally-disposed moving belt which moves lengthwise of the container, these belts being arranged vertically with respect to each other such that the material, in traveling from the entrance end of the vessel toward the exit end thereof, drops downwardly off the far end of the feed belt onto the near end of the mixing belt, and then drops downwardly off the far end of the mixing belt onto the near end of the reaction belt. Each of the three belts passes over a respective pair of rollers, and each is driven by a suitable driving means. At the first or entrance end of the vessel,
means is provided for feeding a layer of hot solid material onto the feed belt, this material being laid down substantially uniformly over the width of the belt. At this same end of the vessel, means is provided for feeding a sheet-like stream of relatively cool fresh raw material to be treated (e.g., tar sand) onto the feed belt and superposed on the layer of hot solid material previously laid down.
After being deposited on the feed belt, the two different types of material travel together to the far end of the feed belt, from whence they drop downwardly onto the mixing belt. The mixing belt functions to cause the two particulate solid materials tobecome intimately mixed with each other, such that the particles of one material are thoroughly and substantially completely dispersed among and between the particles of the other material.
The aforesaid mixture of the two materials drops downwardly off the far end of the mixing belt onto the reaction belt, which is considerably longer than either the mixing belt or the feed belt, and which serves as a (moving) residence platform. Since the admixed and intermixed materials are in close, direct physical contact with each other at the time they reach the reaction belt, they are in intimate thermal contact, and since there is a rather large temperature difference between the particles of the two types, a heat exchange takes place, the temperature of the fresh raw material increasing as the materials are moved by the reaction belt through the reaction zone, toward the far or exit end of the vessel. Due to the heating, volatilizable constituents are driven off from the raw material, the evolved gases escaping from the vessel through a gas collecting port as gaseous products (vapors).
By the time the (initially relatively cool) fresh raw material reaches the exit end of the vessel, it has been heated sufiiciently so that most of the gaseous constituents have been driven off therefrom, but this retorting or pyrolyzing process (the driving off, by heat, of the volatilizable constituents from the fresh raw material) results in the leaving of a combustible (carbon, or coke) deposit on the spent material. All of the solid material which has traveled through the vessel to the exit end thereof, which is to say, both the spent material (which started through the vessel as fresh raw material) and the (originally hot) solid material (which has been used in the vessel as a heat transfer medium), drops off the far end of the reaction belt, and it is then abstracted from the vessel and conveyed to a separate regenerator. In the regenerator, the combustible carbonaceous deposit on the spent material is burned, by means of air or other combustionsupporting gas supplied to the regenerator. This burning serves to heat all of the solid material in the regenerator, and a portion of this heated material is taken from the regenerator and fed to the first or entrance end of the vessel, to serve as the hot solid material which is mixed with the fresh raw material to give up heat to this latter material, for the pyrolysis, distillation, or retorting previously described. In other words, this lastmentioned hot solid material serves as the heat transfer medium.
The remainder of the heated material at the outlet of the regenerator is sent to storage (as waste).
A detailed description of the invention follows, taken in conjunction with the accompanying drawings, wherein:
FIGS. 1A and 1B together constitute FIG. 1, which is a partly diagrammatic and partly structural representation of a pyrolysis apparatus according to this invention.
The apparatus of the invention will be described below using oil-bearing sand (often termed tar sand) as an example of the solid material which can be processed by the apparatus of the invention. It is noted, however, that apparatus of this type might be used for the distillation or carbonization of other carbonizable materials, and
quite generally for the recovery of volatilizable constituents from subdivided solids containing the same.
Referring now to the drawings, and particularly to FIG. 1A, an elongate fixed vessel 1, which may be thought of as a reactor, is generally cylindrical in shape and is mounted on its side so that its longitudinal axis extends horizontally, as shown. This vessel is mounted on a fixed base or support (not shown). Vessel 1 is closed at its ends by means of suitable end closures; for convenience in illustration, the end closure at the near or left-hand end of the reactor has been removed.
At the near end of vessel 1, a transversely-extending shaft 2, whose axis is located near the top of the cylindrical vessel, is journaled for rotation at its two opposite ends in the cylindrical wall of vessel 1, as by means of bearing assemblies such as 3 (schematically illustrated) which, in addition to their function of rotatably supporting the ends of the shaft, act to seal the ends of the shaft 2 through the reactor wall. One end of shaft 2 (for example, the near end in FIG. 1A) may extend outwardly as at 211 beyond the cylindrical wall of vessel 1, for a purpose which will be explained hereinafter. A cylindrical roller 4, of rather large diameter, is fixedly secured to shaft 2 intermediate the ends thereof and within vessel 1. The roller 4 is coaxial with shaft 2 and is of rather substantial length, occupying most of the space available within vessel 1, along the chordal axis of shaft 2.
The vessel 1 has both a substantial length and a substantial diameter. At a location spaced some distance along the length of vessel 1 (toward the right-hand end thereof) from shaft 2, a transversely-extending shaft 5, whose axis is located in the same horizontal plane as the axis of shaft 2, is journaled for rotation at its two opposite ends in the wall of the vessel, as by means of bearing assemblies such as 6 which are similar to assemblies 3 and which rotatably support shaft and also provide shaft seals. One end of shaft 5 may extend outwardly as at 5a beyond the cylindrical wall of vessel 1. A cylindrical roller 7, similar to roller 4, is fixedly secured to shaft 5, coaxially thereof and within vessel 1. It Will be realized, from the foregoing, that roller 7 is substantially parallel to roller 4, and the axes of both shafts 2 and 5 are substantially horizontal.
A conventional source of motive power, for example an electric motor (not shown) operating through an appropriate gear reducer (also not shown), is suitably coupled to the outer ends of one or both of the respective shafts 2 and 5, to rotate these shafts at an appropriate rate of speed. Preferably, the driving arrangement for these shafts is provided with a speed adjustment means. As will be understood, rollers 4 and 7 will rotate at the same rate when the motive power source is energized.
A rather wide flat endless metallic feed belt 8, made of stainless steel for example, whose width is approximately equal to the length of rollers 4 and 7, passes over these rollers and is driven thereby in the direction indicated by arrow 9, such that the upper side of this belt moves from roller 4 to roller 7.
The near or left-hand end of vessel 1 may be termed the entrance end of the vessel. At this end of the vessel, adjacent roller 4, a vertically-positioned short pipe or conduit 10 is sealed through the top of vessel 1, this pipe having at its upper end a flange 11 by means of which it may be coupled to a supply pipe 12 (schematically illustrated in FIG. 1B). A fan-shaped distributor member 13 (which may be likened to an upside-down or upended funnel) has its narrow upper end coupled to the inner or lower end of pipe 10, inside vessel 1, and has at its lower wide or fan end an opening which is spaced just slightly above the upper surface of belt 8. The width of the opening at the lower or fan end of member 13 (measured parallel to the width of the belt, or at 90 to the direction of travel of the belt) is substantially equal to the width of the belt, and the length dimension of the opening at the fan end of member 13 (measured parallel to the direction of travel of the belt) is rather small.
Hot particulate solid material supplied to hot sand inlet pipe 10 (by way of example, this material may be hot clean sand, as will be described subsequently) flows downwardly by gravity through member 13, and is constrained or guided by this latter member to be distributed over substantially the entire width of the upper surface of belt 8. That is to Gay, as belt 8 moves in the direction 9, the member 13 lays down continuously on the bare belt, over substantially the entire width of the upper surface thereof, a layer of hot particulate solid material (assuming, of course, that sufficient material is supplied in a continuous manner to inlet pipe 10) At a location slightly beyond (in the direction of travel 9 of belt 8) pipe 10, a vertically-extending nozzle member 14 is sealed into the top of the vessel 1. Nozzle 14, like the opening at the lower end of member 13, has an effective width substantially equal to the width of belt 8, and a rather small length dimension. The lower open end of nozzle 14 terminatesat and is sealed into a hole in the cylindrical wall of vessel 1, so it can be said that the lower end of the nozzle terminates at such wall. Thus, the lower end of nozzle 14 is cut along an arc which matches that of the cylindrical wall of vessel 1, and the lower end of this nozzle communicates with the interior of the vessel. It will be noted that the lower open end of nozzle 14 is located some distance above the upper surface of belt 8.
The upper end of nozzle 14 is flanged at 23 to provide a coupling means for this nozzle, and this flange is fastened to a similar flange 15 provided at the lower end of a vertically-extending chute 16. The cross-section of chute 16 is preferably the same as that of nozzle 14. At the upper end of chute 16, an inclined platform 17 is fastened to the chute, and a vibrating spreader 18 of known type is mounted above platform 17 to feed material into the upper end of chute 16. Platform 17 is inclined downwardly toward chute 16. Spreader 18 is of enclosed design, and is driven by a vibratory driving mechanism of conventional type in such a manner that a solid particle tending to travel downwardly as at 22 along the inclined floor 19 will actually be caused to travel in the zigzag path indicated at 20. The fresh raw material to be treated (for example, oil-bearing sand) is fed vertically into one end of the spreader 18, as indicated by arrows 21, from a controlled feed chute (not shown), and drops onto the upper end of floor 19. The lower end of the spreader floor is located substantially directly above the upper end of chute 16, and this floor is above platform 17. The subdivided particulate solid material entering the spreader 18 at 21 travels downwardly in zigzag fashion along floor 19 toward chute 16, as indicated at 20, and as it does so, is spread out or dispersed (as a result of the action of spreader 18) substantially uniformly over the entire width of floor 19. This results in the establishment of a thin sheet of fresh raw material which drops off the lower end of floor 19 into the upper end of chute 16. Of course, the aforementioned sheet of material is actually composed, collective ly, of individual particles of the subdivided solid material fed at 21 into spreader 18.
The sheet of material dropping off the lower end of spreader floor 19 enters the upper end of chute 16, and moves downwardly by gravity through this chute and through nozzle 14, to the lower end of the latter. As previously mentioned, the lower end of nozzle 14 is coextensive with a portion of the cylindrical wall of hollow vessel 1, this portion being located at the top of the vessel. The sheet-like stream of fresh raw (particulate solid) material leaving the lower end of nozzle 14 drops in freefall fashion (as indicated by arrows 24) onto the upper surface of belt 8 as the latter travels in the direction 9. Since nozzle 14 is located beyond distributor member 13 (referring to the direction of travel 9 of the belt), the sheet-like stream of fresh raw material will be dropped onto feed belt 8 in superposed relation to the layer of hot solid material already deposited thereon via feed pipe 10 and distributor member 13.
In order to prevent the loss of hydrocarbon vapors (valuable product) from vessel 1 via nozzle 14, stream is supplied from a suitable source to a plurality of apertures 26 provided in nozzle 14, to provide in effect a sealing blanket of steam within the nozzle, through which blanket the stream of raw material moves downwardly into vessel 1.
Distributor member 13 is at all times maintained sufficiently filled with solid material to provide a choke for preventing the escape of vapors from vessel 1 outwardly through pipe 10, and also to ensure that this material spreads out properly at the lower end of member 12.
Below shaft 5, and approximately in the same vertical plane therewith, a transversely-extending shaft 27 is journaled for rotation at its two opposite ends in the wall of vessel 1, as by means of bearing assemblies such as 28 which rotatably support shaft 27 and also provide shaft seals. One end of shaft 27 may extend outwardly as at 27a beyond the cylindrical wall of vessel 1. A cylindrical roller 29 is fixedly secured to shaft 27, coaxially thereof and within vessel 1.
At a location spaced some distance along the length of vessel 1 (toward the right-hand end thereof) from shaft 27, a transversely-extending shaft 30, whose axis is located in the same horizontal plane as the axis of shaft 27, is journaled for rotation at its two opopsite ends in the wall of the vessel, as by means of bearing assemblies such as 31 which are similar to assemblies 28 and which rotatably support shaft 30 and also provide shaft seals. One end of shaft 30 may extend outwardly as at 30a beyond the cylindrical wall of vessel 1. A cylindrical roller 32, similar to roller 29, is fixedly secured to shaft 30, coaxially thereof and within vessel 1. It will be realized, from the foregoing, that roller 32 is substantially parallel to roller 29, and the axes of both shafts 27 and 30 are substantially horizontal.
A rather wide flat endless metallic mixing belt 33, made of stainless steel for example, whose width is approximately equal to the length of rollers 29 and 32, passes over these rollers and is driven thereby in the same direction 9 as belt 8, i.e., the upper side of belt 33 moves from roller 29 to roller 32. Mixing belt 33 is positioned sufficiently below feed belt 8 so as not to interfere with the movement of the latter, and is so aligned with feed belt 8 that the solid material mixture drops off the far or righthand end of belt 8 onto the near or left-hand end of belt 33.
A separate driving arrangement (which may be similar to the driving arrangement utilized for the feed belt 8) is provided for mixing belt 33, the driving arrangement for belt 33 having its own speed adjustment means. As will be understood, rollers 29 and 32 will both rotate at the same rate when the motive power source for the shafts 27 and 30 is energized.
In addition to its longitudinal motion in the direction 9 as previously referred to, mixing belt 33 is caused to execute a vibratory motion in a plane more or less at right angles to the longitudinal direction of travel of the belt. Thus, this belt is preferably vibrated up and down in a vertical direction, although in some instances it may be vibrated back and forth in a lateral direction, similarly to the spreader floor 19 previously described. Any suitable means may be coupled to belt 33 to cause it to vibrate in the manner aforementioned. By way of example, an eccentric cam or roller can be used for this belt, in place of the straight cylindrical rollers 29 and/or 32. Or, a vibrator of known type can be mounted under the belt.
The purpose of the vibratory motion of mixing belt 33 is to effect a thorough physical mixing together of the particulate material being moved by this belt, such that the particles of one type (to wit, the fresh raw sand entering the vessel by way of nozzle 14) become thoroughly and substantially completely dispersed among and between the particles of the other type (to wit, the hot solid material entering the vessel through distributor member 13). That is to say, a substantial admixing and intermixing of the two types of particles takes place as a result of the vibratory motion of mixing belt 33, such that the two materials are in close, direct, and intimate physical contact with each other by the time they reach the far or right-hand end of this belt (at roller 32). Thus, the raw sand particles are brought into intimate thermal contact with the particles of hot solid material by the time the mixture carried by belt 33 reaches the far end thereof.
Below shaft 30, and approximately in the same vertical plane therewith, a transversely-extending shaft 34 is journaled for rotation at its two opposite ends in the wall of vessel 1, as by means of bearing assemblies such as 35 which rotatably support shaft 34 and also provide shaft seals. One end of shaft 34 may extend outwardly as at 34a beyond the cylindrical wall of vessel 1. A cylindrical roller "36 is fixedly secured to shaft 34, coaxially thereof and within vessel 1.
At a location close to the right-hand end of vessel 1, a transversely-extending shaft 37, whose axis is located in the same horizontal plane as the axis of shaft 34, is journaled for rotation at its two opposite ends in the wall of the vessel, as by means of bearing assemblies such as 38 which are similar to assemblies 35 and which rotatably support shaft 37 and also provide shaft seals. One end of shaft 37 may extend outwardly as at 37a beyond the cylindrical wall of vessel 1. A cylindrical roller 39, similar to roller 36, is fixedly secured to shaft 37, coaxially thereof and within vessel 1. It will be realized, from the foregoing, that roller 39 is substantially parallel to roller 36, and the axes of both shafts 34 and 37 are substantially horizontal.
A rather wide flat endless metallic reaction belt 40, made of stainless steel for example, whose width is approximately equal to the length of rollers 36 and 39,. passes over these rollers and is driventhereby in the same direction 9 as belts 8 and 33, i.e., the upper side of belt 40 moves from roller 36 to roller 39. Reaction belt 40- is positioned sufficiently below mixing belt 33 so as not to interfere with movement of the latter, and is so aligned with mixing belt 33 that the solid material mixture drops off the far or right-hand end of belt 33 onto the near or left-hand end of belt 40.
The reaction belt 40 has a substantial length, such as to serve as a (moving) residence platform within vessel 1. Belt 40 is considerably longer than the feed belt 8 or the mixing belt 33, and belt 40 may, if necessary, comprise a plurality or series of vertically-disposed and longitudinally-aligned shorter belts.
A separate driving arrangement (which may be similar to the driving arrangements utilized for belts 8 and 33) is provided for reaction belt 40, the driving arrangement for belt 40' having its own speed adjustment means. As will be understood, rollers 36 and 39 will both rotate at the same rate when the motive power source for the shafts 34 and 37 is energized. The several shaft extensions 2a, Sa, 27a, 30a, 34a, and 37a permit the several driving arrangement to be coupled to the respective shafts. The several belts 8, 33, and 40 may be of different widths, due to their vertically-spaced relationship, transversely of the cylindrical vessel 1. The separate and distinct driving arrangements, each with its own speed control, provided for the respective belts, enable proper feeding of the material through the vessel despite the differences in belt widths; also, these driving arrangements permit a wide variation in feed rates during use of the apparatus.
As previously described, the two types of particulate or subdivided solid material are thoroughly intermixed with each other, and are thus in intimate thermal contact with each other, by the time they reach the near or lefthand end of belt 40. This mixture of hot solid material and raw sand is moved from left to right in vessel 1 by reaction belt 40. Since the particles of the two types of material are in such intimate thermal contact, a heat exchange takes place therebetween, in which the hot solid material gives up heat to the cooler raw sand. This serves to heat the fresh raw material (tar sand) to a retorting temperature wherein thermal cracking of the raw tar sand takes place. When the fresh raw tar sand reaches a temperature of about 800-l000 F., its kerogen content is broken down to hydrocarbon vapors. That is to say, the direct physical contact of the two types of particulate material which exists, during their residence time together on reaction belt 40, will cause gases to be evolved from the fresh raw tar sand, as a result of the retorting and thermal cracking of the latter. The evolved gases comprise product gases (hydrocarbon vapors) which are removed as at 25 from the upper portion of vessel 1, by way of a vapor exit port 41 to which a suitable pipe (not shown) is connected. By means of this last-mentioned pipe, the gaseous products are carried away from vessel 1 for further processing, such as in a condenser and scrubber (not shown).
The holding or residence time in vessel 1 for fresh raw material (i.e., the time during which the particles of fresh raw material and of hot spent recycled material are in contact on belt 40) is established by, among other things, the length of this reaction belt between rollers 36 and 39 and the speed of travel of the belt. The holding time of the solids mixture in vessel 1 can be any suitable time, depending upon the temperature of the hot spent (heating) material which is recycled. It should be sufficiently long to ensure adequate removal of vaporizable hydrocarbons from the raw material, but should be short enough to avoid excessively high equipment and process costs. The direct and intimate contact between the solid particles in vessel 1, and the consequent rapid heat transfer between the two types of particles, contribute to the overall efiiciency of the process.
When belt 40 reaches roller 39, the residence time of the solids mixture in vessel 1 is in effect ended. At this time, the raw material traveling through vessel 1 has reached a condition (during its cracking) such that it is not desirable to extract further products from it.
When reaction belt 40 passes over roller 39, all of the material carried on the upper surface of this belt drops off and falls to the bottom of the vessel. This includes both the regenerated material which is being recycled through the vessel for heating purposes (and which reaches the vessel via pipe and the fresh raw material (reaching the vessel via nozzle 14) which has been thermally cracked upon one pass through the vessel and has thus become spent.
At the right-hand end of vessel 1, at a location adjacent roller 39, the upper end of a vertically-extending nozzle member 42 is sealed into'the bottom of this vessel. By way of example, nozzle 42 may have the same crosssection as nozzle 14. The upper open end of nozzle 42 terminates at and is sealed into a (circumferentiallyextending) hole in the cylindrical wall of vessel 1, this end of the nozzle communicating with the interior of vessel 1 at a location such that the material dropping off belt 40 at roller 39' falls into the upper end of nozzle 42. This material then moves downwardly through this nozzle.
The upper end of a short chute member 43 is coupled to the lower end of nozzle 42, as by means of a flanged coupling arrangement 44. The cross-section of chute 43 is preferably the same as that of nozzle 42. The lower end of chute 43 is sealed into the side wall of a pipe or conduit 45, at one end thereof. Pipe 45 is located below vessel 1 and extends outwardly or away from vessel 1; purely by way of example (as illustrated), pipe 45 may extend in a direction at right angles to the longitudinal axis of vessel 1. The material dropping off the belt at roller 39 moves downwardly through nozzle 42 and chute 43 into pipe 45. In order to prevent the loss of hydrocarbon vapors (product) from vessel 1 via nozzle 42, steam is supplied from the steam source to a plurality of apertures 46 provided in nozzle 42, to provide in effect a sealing blanket of steam within this nozzle, through which blanket the exiting material moves downwardly out of vessel 1.
A helical screw conveyer (auguer) 47 is rotatably mounted within pipe and is driven by any conventional source of motive power, such as an electric motor. The rotating screw conveyer 47 moves the solid material through pipe 45, away from vessel 1.
The solid material exiting at 42 from vessel 1 comprises a mixture of clean sand (to wit, regenerated material which has been recycled through vessel 1 to serve as a heating medium) and spent sand (to wit, raw sand which has been retorted in vessel 1). The spent sand component or portion of this mixture of solids, though spent insofar as the removal of valuable products therefrom is concerned, nevertheless has a combustible carbonaceous (carbon or coke) deposit or coating or residue thereon, which may be burned off, in a regenerator, to provide heat. This burning heats the material in the regenerator, as well as decoking the spent sand component thereof, and a portion of this (now clean) material may be recycled through vessel 1 as the hot solid material which provides heat for heating the fresh raw material. It will be appreciated that this hot solid material is recycled through vessel 1 by way of inlet pipe 10 and member 13.
In order to decoke the dirty or coked material, a regenerator (which may be thought of as a decoking zone) is utilized.
Pipe 45 extends from vessel 1 to a regenerator schematically shown and denoted generally by numeral 48 (see FIG. 1B). Pipe 45 serves as the feed pipe for the regenerator, and opens into the upper portion of the regenerator. A coke burner 49, to which air is supplied at 50, serves as the means for burning the coke deposit off the body of material in the upper part of the regenerator. The coke burner 49 is mounted at the lower end of the regenerator. In the regenerator 48, good contact of preferably preheated air with the mixture exiting from reactor 1 (which is fed to regenerator 48 by means of pipe 45, and is denoted by numeral 51) is afforded for a sufficiently long period of time to ensure efiicient combustion of the carbonaceous residue on the coked portion of this mixture, so as to produce the desired hot decoked solids.
Gases produced during burning of hydrocarbons from the spent sand component of the material in regenerator 48 can be passed into a cyclone 52, for separation of entrained fines therefrom, which fines can then be returned to regenerator 48 through a line 53. The gases flowing from the cyclone 52 through line 54 can pass into a surge chamber 55 and then can be vented from the system in the form of flue gas, as by line 56.
A portion of the spent solids from vessel 1 is disposed of as waste. This portion passes from coke burner 49 through a cooler 57 and thence out of this cooler by way of a line 58, which leads to waste storage.
The regenerator 48 may be started up by introducing liquid or gas fuel into the combustion zone, as by means of a line 59. For start-up, material would be fed through the reactor 1 and the regenerator 48 just as if the carbon or coke deposit were burning in the decoking zone or regenerator. Then, a fire would be lit in the regenerator (using the fuel supplied at 59) by a procedure similar to firing up a boiler. Once the reactor has started producing gas of its own (at 25), the outside source of fuel could be closed off and the regenerator would burn the products of the reactor, this continuing until the regenerator has come up to operating temperature. Then, the regenerator would operate on the residual carbon or coke deposits on the spent sand portion of the reactor exiting mixture, in the manner described above.
As previously described, the exiting solids mixture continuously passes out of the exit end of the reactor 1 (which end, of course, is that at which roller 39 is located) to regenerator 48, by way of pipe 45. In the regenerator or decoking zone 48, the coked or dirty portion of the exiting solids mixture is continuously decoked by burning the carbonaceous residue in contact with air (supplied at 50), the material in the regenerator being heated to 1200 F. by such burning.
A more or less conventional steam stripping arrangement, shown schematically at 60, is provided in regenerator 48, for the purpose of abstracting from the regenerator some of the hot clean solids for recycling to the reactor 1; it will be remembered that the remainder of the clean solids are disposed of as waste. The hot, entirely clean solids stripped out of the decoking zone at 60 pass downwardly through an inclined pipe 61 into the upper end of a hopper 62. From hopper 62, the hot clean material, entirely decoked, is fed by means of a supply pipe 12 (schematically illustrated in FIG. 1B) to hot sand inlet pipe of the reactor 1. Pipe 12 has at its end remote from hopper 62 a flange (not shown) which is coupled to flange 11 on inlet pipe 10. The hot clean material (hot solids) may be fed through pipe 12, using steam as the motive fluid to move this material upwardly to flange 11 and inlet pipe 10; such a steammotived arrangement is a well-known practice in fluid catalytic crackers (for moving the regenerated catalyst).
Preferably, a throttle valve (not shown) is provided in line 12, for regulating the relative amounts of raw sand and recycled hot sand fed to reactor 1.
As previously stated, the material in regenerator 48 is heated to 1200 F. by burning of the carbonaceous residue (i.e., decoking) in the regenerator. A portion of the clean hot solids is stripped out at 60, and fed as recycle (by way of pipe 61, hopper 62, and pipe 12) to the reactor 1 for use in heating the fresh raw tar sand continuously passing into the reactor by way of nozzle 14. That is to say, the coke-free hot solids which flow in the previously-mentioned path are recycled and used for heating the fresh raw material in reactor 1; the said hot solids (hot sands) are deposited as a layer on feed belt 8 by means of distributor member 13. As previously described, fresh raw material (tar sand) is deposited on belt 8 in superposed relation to the layer of hot solid (coke-free, recycled) material on this belt, followed by mixing of the two solids by belt 33, and so on.
The invention claimed is:
1. Apparatus for continuously treating carbonaceous solid material such as tar sand and the like, comprising an elongate vessel, an endless paltform belt passing over a pair of rollers one of which is located near one end of said vessel and the other of which is located at the other end thereof, a feed belt mounted in said vessel for movement from said one end thereof toward said other end thereof, a vibratory mixing belt mounted in said vessel for movement from a location near said one end thereof toward said other end thereof and interposed between said platform belt and said feed belt, said mixing belt being arranged to receive, at one end thereof, solid material leaving said feed belt and to feed a mixture of solids from its other end onto said platform belt; first means at said one end of said vessel for feeding hot particulate solid material onto said feed belt, second means at said one end of said vessel for feeding relatively cool particulate solid material which is to be treated onto said feed belt in superposed relation to said hot solid material, means associated with said second feeding means for providing a sealing blanket of steam through which the material to be treated moves on its Way toward said feed belt, said mixing belt acting to bring the particles of the hot material and the particles of the relatively cool material into intimate physical and thermal contact with each other; means for removing vapors from said vessel, means at said other end of said vessel for abstracting from said vessel solid material which has been moved to such end by said platform belt, means associated with said abstracting means for providing a sealing blanket of steam through which the abstracted material moves on its Way out of said vessel, 21 regenerator coupled to said abstracting means for receiving abstracted solid material therefrom and for burning a combustible carbonaceous deposit present on such abstracted material, such burning serving to heat the abstracted solid material; and means coupled to the outlet of said regenerator for supplying the heated material to said first feeding means, to provide the hot particulate solid material for feeding into said feed belt.
2. Apparatus according to claim 1, wherein said second feeding means includes a vibrating spreader to which the solid material to be treated is supplied, and a chute receptive of material from said spreader and adapted to convey such material to said feed belt, the first-mentioned sealing blanket of steam being provided in said chute.
3. Apparatus according to claim 1, wherein said first feeding means includes an inverted funnel-shaped member receptive of said hot particulate solid material and overlying said feed belt.
4. Apparatus according to claim 1, where in said abstracting means includes an elongated nozzle member sealed into the wall of said vessel at said other end thereof and receptive of solid material dropping off of said platform belt, the second-mentioned sealing blanket of steam being provided in said nozzle member.
5. Apparatus according to claim 1, wherein the coupling between said abstracting means and said regenerator includes a screw conveyor for conveying solid material from said abstracting means to said regenerator.
References Cited UNITED STATES PATENTS 1,698,345 1/1929 Puening 202-117 1,952,363 3/1934 Bunce et al 2021l7 2,621,151 12/1952 Carlsson et a1 202117 2,905,595 9/1959 Berg 208-11 2,983,653 5/1961 Danulat et al 20133 FOREIGN PATENTS 129,758 7/1919 Great Britain.
71,711 4/1931 Sweden.
NORMAN YUDKOFF, Primary Examiner.
DAVID EDWARDS, Assistant Examiner.
US. 01. X.R.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US1698345 *||Feb 11, 1922||Jan 8, 1929||Franz Puening||Art of distilling carbonaceous materials|
|US1952363 *||Apr 29, 1931||Mar 27, 1934||New Jersey Zinc Co||Apparatus for coking agglomerates|
|US2621151 *||Mar 10, 1948||Dec 9, 1952||Ingeniorsbyran Fredca Aktiebol||Coal and the like|
|US2905595 *||Sep 16, 1955||Sep 22, 1959||Union Oil Co||Tar sand distillation process and apparatus|
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|GB129758A *||Title not available|
|SE71711A *||Title not available|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US4388174 *||Jun 10, 1982||Jun 14, 1983||Metallgesellschaft Aktiengesellschaft||Process of recovering oil from oil-containing minerals|
|US5320746 *||Nov 1, 1990||Jun 14, 1994||Exxon Research And Engineering Company||Process for recovering oil from tar sands|
|EP0049343A1 *||Aug 11, 1981||Apr 14, 1982||Uhde GmbH||Process for the desorption of loaded solid adsorbents|
|U.S. Classification||196/120, 196/124, 202/117, 196/123, 208/391, 202/111|
|International Classification||C10G1/02, C10B49/20, B01J8/16, C10G1/00, C10B49/00|
|Cooperative Classification||B01J8/16, C10G1/02, C10B49/20|
|European Classification||C10G1/02, B01J8/16, C10B49/20|