Patent application title: DEVICE FOR UPGRADING SOLID ORGANIC MATERIALS
Inventors:
Harsudi Supandi (Jakarta Utara, ID)
IPC8 Class: AC10L908FI
USPC Class:
44492
Class name: Fuel and related compositions peat process including heat
Publication date: 2014-10-02
Patent application number: 20140290130
Abstract:
A device for upgrading a solid organic material into a resulting product
comprises a reactor with an organic material inlet, and a flue gas inlet
adapted to introduce flue gas into the reactor, an input driver adapted
to continuously transfer the solid organic material to the organic
material inlet, an output driver adapted to continuously transfer the
solid organic material out of the reactor, a gas flow element operatively
connected to the flue gas inlet permitting flue gas to mix with the solid
organic material but restricting flow of the solid organic material away
from the flue gas inlet, and a rapid cooling device operatively connected
to the output driver and adapted to apply a heat transfer liquid directly
onto the solid organic material and thereby form the resulting product.Claims:
1. A device for upgrading a solid organic material into a resulting
product comprising, in combination: a reactor with an organic material
inlet, a reactor wall, a solid organic material outlet, a flue gas inlet
adapted to introduce low oxygen flue gas having a temperature greater
than 600.degree. C. into the reactor, and a flue gas outlet; an input
driver adapted to continuously transfer the solid organic material to the
organic material inlet; an output driver adapted to continuously
transfers the solid organic material out of the reactor through the solid
organic material outlet, wherein gravity urges the solid organic material
from the organic material inlet to the solid organic material outlet; a
gas flow element operatively connected to the flue gas inlet permitting
flue gas to mix with the solid organic material, wherein the flue gas
inlet is positioned below the gas flow element and above the solid
organic material outlet, and the flue gas outlet is positioned above the
gas flow element and is adapted to receive flue gas from the reactor; and
a rapid cooling device operatively connected to the output driver and
adapted to apply a heat transfer liquid directly onto the solid organic
material and thereby form the resulting product.
2. The device of claim 1 wherein the reactor defines at least one dryer, and the dryer contains the gas flow element, and the reactor further comprises a first setter operatively connected to the at least one dryer and adapted to receive both solid organic material from the at least one dryer and flue gas.
3. (canceled)
4. The device of claim 2 wherein the reactor further comprises a second setter operatively connected to the at least one dryer and adapted to receive both solid organic material from the at least one dryer and flue gas.
5. The device of claim 4 wherein the first setter and second setter are connected to the dryer in series.
6. The device of claim 5 further comprising a flue gas generators operatively connected to the second setter, and a flue gas generator operatively connected to the first setter; and the first setter has a flue gas outlet connected to the flue gas inlet of the dryer.
7. The device of claim 6 wherein the second setter has a flue gas outlet operatively connected to the flue gas inlet of the dryer.
8. The device of claim 2 further comprising an air inlet into the setter, adapted to introduce air into the setter.
9. The device of claim 1 further comprising a hopper positioned within the reactor, with a hopper wall separated from the reactor wall by a gap, wherein the hopper is adapted to receive the solid organic material from the organic material inlet.
10. The device of claim 9 wherein the gas flow element comprises a plurality of gas flow elements extending through the hopper wall to the gap in one direction and a plurality of gas flow elements extending in another direction through the hopper wall to the gap.
11. The device of claim 10 wherein the hopper forms a constriction beneath the plurality of gas flow elements.
12. (canceled)
13. (canceled)
14. The device of claim 1, further comprising a cyclone adapted to receive flue gas in a flue gas outlet extending from the reactor, wherein the cyclone is adapted to remove fine particles of the solid organic material present in the flue gas.
15. The device of claim 14, further comprising a scrubber adapted to receive flue gas from the flue gas outlet.
16. The device of claim 1 further comprising a controller operatively connected to the input driver, the output driver, and the flue gas generator; wherein the controller can control flow of the solid organic material and the flue gas into the reactor.
17. A method for upgrading a solid organic material into a resulting product comprising, in combination, the steps of: introducing the solid organic material into a reactor having an organic material inlet and a solid organic material outlet; introducing a flue gas having a temperature of at least 600.degree. C. into a flue gas inlet of the reactor and into contact with the solid organic material, and thereby heating the solid organic material, wherein the flue gas flows from the flue gas inlet, past the solid organic material and to a flue gas outlet; removing heated solid organic material from the reactor through the solid organic material outlet positioned below the flue gas inlet, wherein gravity urges the solid organic material from the organic material inlet to the solid organic material outlet; and rapidly cooling the heated solid organic material by applying a liquid directly into the solid organic material and thereby form the resulting product.
18. The method of claim 17 wherein the step of introducing the solid organic material into the reactor and the step of removing the heated solid organic material from the reactor occurs continuously.
19. (canceled)
20. (canceled)
21. The method of claim 17 wherein the reactor comprises a dryer, a first setter, and a second setter, and further comprising the step of transferring the heated solid organic material from the dryer to the first setter, and then from the first setter to the second setter.
22. (canceled)
23. The method of claim 21, wherein the flue gas is supplied by flue gas generators, each operatively connected to a corresponding one of the first setter and the second setter; and further comprising the step of transferring flue gas after the flue gas has traveled through each of the first setter and second setter to a flue gas inlet on the dryer.
Description:
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority benefit of U.S. Provisional Patent application 61/705,190, filed on Sep. 25, 2012, the disclosure of which is expressly incorporated herein in its entirety by reference.
FIELD OF THE INVENTION
[0002] This invention relates to a device for upgrading of solid organic materials, and more particularly to a device for upgrading of solid organic materials suitable for high volume operations.
BACKGROUND OF THE INVENTION
[0003] Solid organic materials include peat, biomass, garbage, and coal, especially low rank coals. Such solid organic materials have been considered as fuel and a source of energy. However, many of these solid organic materials contain relatively large amounts of water--often on the order of 30-60% by weight or more. Because of this high water content, and related low energy density, such solid organic materials have been commercially unattractive for use in industry, especially when the industry that needs the fuel, such as power plants, are located remote from the source of the fuel.
[0004] Large quantities of coal, including low rank coals such as lignite and sub-bituminous coal exist at many places in the world. Technologies have been developed in an effort to dry such organic materials, upgrading their calorific content. However, known technologies for drying such organic materials are either expensive and/or introduce additional problems which have hitherto made the technologies uneconomical. For example, low rank coal can be heated and dried, and its rank increased, but the resulting product can resorb moisture. Also coal can undergo spontaneous combustion, especially low rank coal which has been dried. Further, such dried low rank coals tend to produce undesirably large amounts of dust.
[0005] In addition to these problems, low rank coals typically have a high water content, making it generally uneconomical to mine low rank coal and then ship it to a central facility for upgrading. Therefore any process for upgrading the rank of coal would typically be done where the coal is mined. Known technologies include fluidized bed systems, hot steam in pressurized vessels, and a briquetting process. To be economically attractive, the total cost of such upgrading technologies must be less than the cost of available higher rank coals. However, to date, none of the known technologies has seen any significant commercial acceptance.
[0006] Many of the known upgrading technologies have used additional additives, heating oils, inert gases, diesel fuel, relatively expensive specialized equipment, etc. Any and all of these additional materials must be shipped to the coal mine, greatly increasing the costs of operation. In addition to cost issues, many of the known technologies have other issues. For example, fluidized bed systems have difficulty with coal fines due to separation of lighter particles from heavier particles (elutriation) during operation. This means that even though fluidized bed systems have often been suggested for use in coal upgrading devices, known fluidized bed systems are not practical for high volume operations. Another technology is the so-called Fleisnner process and its variants. These processes are typically batch operations which inherently run relatively slowly, which is again not desirable for high volume coal mining operations. Another known technology is briquetting. With the briquetting technologies, low rank coal is pulverized to very fine particulates and pressed into a series of briquettes. However, the problems associated with dust have not been eliminated, and typically an additional resin or binder has to be added to the coal to help form the briquettes, and/or the coal used is limited to those types of coals with relatively high amounts of naturally occurring resin.
[0007] More recently, other technologies for upgrading organic materials have been described in PCT/ID2012/000002. The reference discusses the use of heating of organic materials by use of flue gas from a gasification burner, described in detail in PCT/ID2012/000001. The flue gas advantageously provides a controlled and uniform heating of the organic material without attendant problems of other upgrading technologies, and provides the source of heat at relatively low cost. However, with large volume operations, high throughput speed of product is greatly desired. It would therefore be desirable to provide a device for upgrading organic materials which still provides controllable and consistent properties yet which is of lower cost and suitable for high volume operations.
SUMMARY OF THE INVENTION
[0008] In accordance with a first aspect, a device for upgrading a solid organic material into a resulting product comprises a reactor with an organic material inlet, and a flue gas inlet adapted to introduce flue gas into the reactor, an input driver adapted to continuously transfer the solid organic material to the organic material inlet, an output driver adapted to continuously transfers the solid organic material out of the reactor, a gas flow element operatively connected to the flue gas inlet permitting flue gas to mix with the solid organic material but restricting flow of the solid organic material away from the flue gas inlet, and a rapid cooling device operatively connected to the output driver and adapted to apply a heat transfer liquid directly onto the solid organic material and thereby form the resulting product.
[0009] From the foregoing disclosure and the following more detailed description of various embodiments it will be apparent to those skilled in the art that the present invention provides a significant advance in the technology of upgrading organic materials. Particularly significant in this regard is the potential the invention affords for providing a low cost, economically viable device for increasing the rank of coal especially suitable for high volume continuous operations. Additional elements and advantages of various embodiments will be better understood in view of the detailed description provided below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a schematic view of a device for upgrading solid organic materials in accordance with one embodiment.
[0011] FIG. 2 is an isolated isometric view of a first reactor on the embodiment of FIG. 1.
[0012] FIG. 3 is a side view of the first reactor.
[0013] FIG. 4 is an isolated view of a hopper in the first reactor.
[0014] FIG. 5 is an isolated isometric view of a baffle in accordance with one embodiment.
[0015] FIG. 6 is an isolated isometric view of a second reactor of the embodiment of FIG. 1.
[0016] FIG. 7 is a side view of the second reactor.
[0017] FIG. 8 is an isolated schematic view of an emission control device attached to a first reactor in accordance with one embodiment.
[0018] FIG. 9 is a schematic view of a device for upgrading solid organic materials in accordance with another embodiment with a single reactor.
[0019] FIG. 10 is an isolated isometric view of a reactor of the embodiment of FIG. 9.
[0020] FIGS. 11 and 12 are cross section views through the reactor of FIG. 10.
[0021] FIG. 13 is a schematic assembly view of another embodiment with a single dryer and a pair of setters connected in series.
[0022] FIG. 14 is an isolated schematic view of an emission control device attached to the first reactor in accordance with one embodiment where a cyclone is used to capture particulate matter.
[0023] FIG. 15 is a simplified schematic of another embodiment where a single dryer is used in conjunction with setters connected in series.
[0024] FIG. 16 is a simplified schematic of another embodiment where a pair of dryers and a pair of setters are used in a sequence of dryer-setter-dryer-setter.
[0025] It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various features illustrative of the basic principles of the invention. The specific design features of the device for upgrading solid organic materials as disclosed here, including, for example, the specific dimensions of the reactors will be determined in part by the particular intended application and use environment. Certain features of the illustrated embodiments have been enlarged or distorted relative to others to help provide clear understanding. In particular, thin features may be thickened, for example, for clarity of illustration. All references to direction and position, unless otherwise indicated, refer to the orientation illustrated in the drawings.
DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS
[0026] It will be apparent to those skilled in the art, that is, to those who have knowledge or experience in this area of technology, that many uses and design variations are possible for the device for upgrading solid organic materials disclosed here. The following detailed discussion of various alternate elements and embodiments will illustrate the general principles of the invention with reference to a device for upgrading low rank coal particular suitable for high volume operations. Other embodiments suitable for other applications, such as drying or upgrading of organic waste materials, will be apparent to those skilled in the art given the benefit of this disclosure.
[0027] Turning now to the drawings, FIG. 1 shows an example of a device 10 for upgrading organic materials such as low rank coals containing relatively high amounts of water in accordance with one embodiment. Substitution or mixing of other organic materials, such as biological sources of carbon (trees, paper, paperboard, woodchips, etc.) or waste materials will be readily apparent to those skilled in the art given the benefit of this disclosure. Upgrading here is understood to both reduce the amount of water content in the organic material and to increase the calorific value of the organic material for a given mass. Typically this is done by pyrolysis, where the solid organic material is heated in a reducing or low oxygen environment.
[0028] The devices in the representative embodiments shown herein have a reactor where hot flue gas comes into direct contact with the solid organic material. Further, conductive heating occurs where the coal rests on surfaces heated by the flue gas. Combining direct and conductive heating advantageously drives off moisture and volatiles more quickly, and allows for quicker upgrading of the product. A device with direct and conductive heating advantageously reduces total residence time and therefore allows for high volume upgrading. The reactor can be a single reactor, a plurality of reactors where separate functions may be performed, or multiple reactors can perform the same function, either in series or in parallel. The reactor may be vertically mounted such that the solid organic material falls from a top of the device to a bottom of the device, or the reactor may be horizontally mounted such that solid organic material moves generally from side to side. In the embodiment of FIG. 1, device 10 has three reactors, a first reactor 30 where the solid organic material is first introduced, and a pair of second reactors 35. The reactors are vertically mounted. In this embodiment, solid organic material is routed on a conveyor belt 70 to an input driver. The input driver can be a hopper and screw connector 80, for example which continuously supplies solid organic material to the corresponding reactor at a solid organic material inlet. Alternatively the input driver can be an extension of the conveyor or another similar device for delivery of solid organic material. Typically the solid organic material is prescreened for a maximum size to help ensure uniform heating as it travels through the device. For example, a pair screening devices may be used, and the solid organic material can be screened to a range of 5 to 50 mm.
[0029] Devices for upgrading solid organic materials such as low rank coal need a source of heat to drive off moisture. The source of heat can be supplied from one heat source or a plurality of heat sources, optionally operatively connected together, advantageously allowing for continuous operation even when one is heat source is down for maintenance. Typically the heat source is flue gas which is the product of combustion of a material such as coal, natural gas, syngas, diesel fuel, etc. One or more flue gas generators may be used. In the embodiment shown in FIG. 1, a pair of flue gas generators 40 is used. As shown, the pair of flue gas generators is operatively connected via piping 37 to respective second reactors 35 so as to deliver a continuous stream of hot flue gas, typically reaching the second reactors at temperatures of greater than 600° C., more particularly 650-1200° C., and more particularly about 900-1150° C. Generally the higher the temperature the quicker the drying and setting, and the shorter the residence times in each reactor. However, the temperature of the flue gas should be less than an ash fusion temperature to the coal (when the solid organic material is coal). Further, it may be desirable to reduce the temperature in one or the other stages. For example, the temperature of the flue gas at the drying stage may be reduced. Particularly suitable for use as flue gas generators are gasification burners such as those disclosed in PCT/ID2012/00001. Other suitable heat sources for the flue gases will be readily apparent to those skilled in the art given the benefit of this disclosure.
[0030] In accordance with a highly advantageous element, the flue gas flows in a direction counter to the movement of the solid organic material through the device. As seen in FIG. 1, the solid organic material is transferred into the first reactor 30 via input driver formed as screw conveyor 80. In the first reactor the solid organic material first comes into contact with the flue gas, at least partially drying the solid organic material. The residence time in the first reactor 30 can vary according to the nature of the solid organic material. For example typical residence time in the first reactor can be 4-30 minutes, and more particularly about 8-30 minutes for some low rank coals. The amount of residence time in the first reactor depends not only on the properties of the solid organic material introduced, but also upon the amount of drying desired. For example, low rank coals with greater original moisture content where it is desired to reduce moisture levels down to around 1% of the total by weight will typically require a longer residence time.
[0031] At the first reactor 30 the solid organic material is heated by the flue gas to temperatures sufficient to drive off moisture, but not sufficient to drive off much in the way of volatiles (defined as non-water vapour materials present in coal which would vaporize at the temperatures of operation of the device). From the first reactor, the heated solid organic material is routed via an output driver, which can comprise, for example, a screw conveyor 82, optionally shrouded. The output driver can be positioned at the bottom of first reactor, and continuously transfers heated solid organic material out of the reactor at a solid organic material outlet. From there, the solid organic material is routed along a transfer device such as conveyor 71 (partially shown in FIG. 1) up to top of the second reactors 35, where it is split evenly and delivered to the second reactors using corresponding second input drivers such as screw conveyors 83, 84 in conjunction with containers 81. The second input drivers 83, 84 in operation, also continuously supplies heated solid organic material to the second reactors 35 at the corresponding solid organic material inlets. Transfer of the heated solid organic material along the transfer device between the first reactor and second reactor occurs without additional heating to the heated solid organic material. There is no direct or indirect heating source added. Elimination of the need for additional heating at this stage allows for significant equipment cost reduction. Without additional heating is understood here to mean that no additional heat source is applied to the transfer device, either directly or indirectly, except for some minor residual heat in the transfer device from the heated solid organic material during operation.
[0032] In the embodiment of FIGS. 1-5, flue gas from the flue gas generators 40 is introduced into the second reactors 35 via piping 37. At the second reactors 35 the second stage of heating occurs, where volatile matter is emitted. Volatile matter in solid organic materials such as coal refers to the components of coal, except for moisture, which are liberated at high temperature in low levels of or absence of oxygen. This is usually a mixture of compounds with carboxyl (--COOH) and hydroxyl (--OH) groups, short and long chain hydrocarbons, aromatic hydrocarbons and some sulfur and sulfur-containing compounds. Typically the stages of drying and setting are not absolutes. Rather, initial heating releases water principally, but may also release some volatile matter. Continued heating evolves the compounds with the carboxyl and hydroxyl groups, then the short chain hydrocarbons. Such materials tend to be emitted more with further heating, such that principal emission of volatile matter occurs in the second reactor in the embodiment of FIGS. 1-5.
[0033] Residence time at each reactor will vary depending on the properties of the solid organic material. For low rank coals, a typical residence time in the second reactors can be, for example 4-40 minutes, and more particularly 15-30 minutes. Overall residence time in both reactors may be 8-80 minutes, for example. Note that the residence time in each reactor need not be identical. In fact, in the embodiment of FIGS. 1-5, since the mass of the solid organic material is reduced significantly in the first reactor 30 (since water is driven off), and there are two second reactors 35, to help ensure relatively even continuous flow the residence time in the first reactor can be different than the residence times in the second reactor. Optionally the number of reactors can be reversed, so that there are a pair of reactors where drying principally occurs and a single reactor where setting occurs. In the second reactor, typically the residence time is sufficient to make the coal at least nearly red hot.
[0034] After heating in the reactors, the heated solid organic material is transferred out of the second reactors with output drivers such as screw conveyors 85, 86 and rapidly cooled with a quenching agent. The heat transfer agent can comprise spraying an aqueous liquid directly onto the heated solid organic material using a device such as a sprayer 99. Steam evolved from this process may be routed to exhaust pipes 97. The act of quenching causes rapid cooling of the heated solid organic material, which forms a resultant product. Typically the time to cool is relatively short. For example, it can take less than two minutes, more preferably less than one minute, to reduce the temperature to less than 100° C., and more preferably to reduce the temperature to less than 80° C. Advantageously, such rapid quenching causes the coal particles to contract, and volatile matter will condense in pores in the coal, thereby helping to hold the coal particles together and reduce the Hardgrove Grindability Index (HGI) of the resulting coal product. HGI is a measurement of the ease with which coal can be pulverized which generally increases with the rank of coal. Optionally the heat transfer agent can comprise a surfactant such as Focust® mixed with the water for rapid cooling, so that a mixture of both may be delivered to the solid organic material. Application of such a heat transfer agent is useful for resisting spontaneous combustion and for resisting ingress of water after treatment of the resulting coal product.
[0035] The resulting product is routed away from the device 10 via a conveyor assembly 73, 75. When the resulting product is upgraded coal, the processed resulting product inherently has different physical and optical properties than naturally occurring coal. Advantageously such new properties can be tailored for particular customer requirements and reduce known problems with dried coals. When used on low rank coal, the device disclosed herein advantageously produces a resulting coal product that has lower water content than the original low rank coal, a higher calorific value, an (HGI) and an ash fusion temperature (which provides an indication of softening and melting behavior of the ash in the coal) can be modified in a controlled manner.
[0036] Optionally a controller 49 may be provided. The controller 49 is operatively connected to the device 10 and can control all aspects of the device, including rate of transfer of solid organic material into the reactors by the input drivers 80, 81, 83, 43, rate of transfer out of the reactors by the output drivers 82, 85, 86, rate of flue gas introduced to the reactors, rate delivery of the solid organic material on the conveyor belts 70, 71, 73, 75, etc. The controller can also be configured to control a flow rate of any additional gases introduced into the reactors, and also control the position of any valves and operation of any fans, if present. Sensors including temperature sensors may be positioned within the reactors to monitor conditions, and the data generated by the sensors may be routed to the controller and used to help ensure high quality and consistent upgrading of the solid organic material. The controller can be programmed to turn off the heat source at specific temperatures, for example, or to introduce additional hot gases as needed, to help provide controlled production of the resulting product.
[0037] FIGS. 2-3 show the first reactor 30 of FIG. 1 in greater detail. The solid organic material inlet is 50, and the flue gas inlet is 36 via connecting pipe 33. Optionally portholes 31, 32 may be provided to allow for visual inspection into the first reactor 30. Solid organic material is introduced at the solid organic material inlet 50, passes into a hopper 93 containing one or more baffles or triangular shaped gas flow elements (referred to herein as t-air flows) 65, 67 which, during operation, advantageously increase heat transfer by allowing flue gas to mix with more of the solid organic material. In the embodiment of FIGS. 1-6, the gas flow elements are t-air flows which form alternating rows. A first row of t-air flows 65 extends in one direction and a second row of t-air flows 67 extends in another direction. Optionally all rows of the t-air flow are operatively connected to the flue gas inlet 36, either directly or indirectly. Flue gas from the flue gas inlet 36 travels through one or more t-air flows up, heating the solid organic material, and eventually exits via flue gas outlet 72 located above a drying zone. Advantageously,the flue gas inlet(s) and outlet(s) are separate from the solid organic material inlet(s) and outlet(s). Further, heat transfer from the hot flue gas to the solid organic material occurs both directly and via conduction. Heating occurs all along the reactor. Heating occurs at the solid organic material which has temporarily accumulated above constriction 59. In this embodiment, both constrictions 57 and 59 are positioned between the setting zone and the solid organic material outlet 34. Generally one or more additional constrictions may be positioned between the drying zone and the setting zone. In this embodiment, the reactor comprises a first reactor 30 and a second reactor 35 operatively connected to the first reactor, with the drying zone located in the first reactor and the setting zone located in the second reactor. The first conveyor conveys the solid organic material to the input driver, and a second conveyor conveys the dried solid organic material to a second input driver connected to the second reactor The solid organic material outlet 39 is positioned below the drying zone, and in this embodiment comprises a pair of solid organic material outlets, one at the first reactor and one at the second reactor.
[0038] The t-air flows are mounted in a hopper 93. As shown, the hopper is generally cylindrical in shape, and has a diameter less than a diameter of the reactor 30 such that a gap exists between the reactor and the hopper wall 91. Mounting elements securing the hopper to the reactor have been removed for clarity of illustration. Flue gas travels through constriction 57 up into the hopper, and flue gas travels through the gap to the t-air flows, allowing for further mixing of the flue gas and the solid organic material. Generally the solid organic material flows around and between the t-air flows, through constriction 57 and accumulates in a pile 55 above the output driver 82, where it is gradually removed via the output driver(s).
[0039] Generally drying occurs first. FIG. 3 shows areas or zones 52 in the hopper and 54 above second constriction 59 and below the hopper as drying zones where the moisture content of the solid organic material is reduced. In this embodiment, principally only drying occurs at the first reactor 30. Given that the temperature of the flue gas can be very high (e.g., greater than 800° C., greater than 850° C., greater than 900° C., and even up to 1100-1250° C.), the reactor wall may be formed of several layers, including an outer layer 41 of a steel, and an inner layer 42 of a high temperature resistant alloy such as SS317 or 253MA, for example. Optionally an air gap may be positioned between layers as well. The hopper 91 may also be formed of the high temperature alloy. The inner layer 42 can also optionally comprise a first ceramic material such as a firebrick, insulating castable or other similar high temperature stable material.
[0040] FIG. 4 is an isolated view of the hopper 93, provided with a series of openings 96 to mount the t-air flows 65 and 67. As can be seen in this Fig., the plurality of t-air flows extend through the hopper wall, allowing flue gas to flow up to the t-air flows, into and underneath them, and thereby heat the t-air flows. Thus, additional heating of the solid organic material can occur by conduction when the solid organic material comes into contact with surfaces of the hopper and of the t-air flow heated by the flue gas. In the embodiment of FIG. 4, t-air flows 65 extend in one direction and t-air flows 67 extend in another direction, shown here as a right angle with respect to t-air flows 65. FIG. 5 shows an isolated isometric view of a representative baffle or t-air flow 60. The t-air flow a pair of walls 63, 64 connected at an angle and defining a space 61 underneath the t-air flow which allows flue gas to flow. The flue gas heats the walls of the t-air flow which in turn heat the solid organic material as it passes through the zone of the reactor with the t-air flows. Optionally an additional wall 62 extending downward from the walls 63, 64 may be provided which may enhance structural stability and increase heat transfer.
[0041] FIGS. 6-7 show views of one of the second reactors 35. Solid organic material previously heated at the first reactor is introduced into the second reactor at second solid organic material inlet 51. Flue gas is routed from the flue gas generator via connecting pipe 37 to second flue gas inlet 69. As shown, second solid organic material inlet 51 is positioned above the second flue gas inlet, in a manner similar to that shown in the first reactor. Heated solid organic material is routed via pipe 94 into the reactor, where it is heated by directly by contact with the hot flue gas, and indirectly via conduction via contact with the heated reactor walls. At the second reactor, mixing of the heated organic material and the flue gas results in some additional moisture driven off, and also raises a temperature of the heated organic material sufficient to drive off volatiles.
[0042] As shown, the solid organic material forms a pile 98. A constriction 66 is shown between the second output driver 86 and the setting zone 56. The flue gas inlet is located at the setting zone, below the second organic material inlet and above the solid organic material outlet 89. As with the first reactor, the walls of the reactor may be formed as a bilayer 43, 44. The wall of the second reactor may be formed of stainless steel, with an interior layer formed of high temperature alloy such as SS317 or 253 MA, for example. Alternatively a firebrick may be used. Since the solid organic material has been previously heated and moisture has been reduced, additional heating performed at the setting zone 56 drives off most of the remaining moisture, but also drives off volatiles.
[0043] Output driver 86 is shown as a screw conveyor. In operation, second output driver continuously transfers heated solid organic material out of the reactor through a second solid organic material outlet 89. As noted above, when the solid organic material exits the constriction 66 and enters the output driver, it is quite hot. In accordance with a highly advantageous element, a rapid cooling device 99 or quencher may be provided the spray a liquid directly onto the heated solid organic material, rapidly cooling the solid organic material and forming the resulting product. Vapour generated by this quenching process may be routed to column 97. The column may be optionally routed to the other exhaust columns.
[0044] In accordance with a highly advantageous feature, flue gas from the second reactor can be routed or transferred into the first reactor via exhaust gas links or connectors 79 and 33 as shown in FIG. 1. Thus flue gas outlets of the second reactor are operatively connected to a flue gas inlet of the first reactor. The flue gas may also include moisture liberated from the heated solid organic material in the second reactors. Further, volatiles may be included. Alternatively, a small amount of air may be introduced into the reactors to flare off or consume the volatiles, such that the exhaust gas links receive flue gas, water vapour, and the products of combustion of the volatiles. As shown in FIG. 1, exhaust gas link 79 is operatively connected to the top of one second reactor 35, and another exhaust gas link 78 is operatively connected to another second reactor 35. The exhaust gas links may meet at connecting pipe 33. Alternatively, the links can extend into the first reactor separately such that the first flue gas inlet comprises a pair of first flue gas inlets. The exhaust gas contains residual heat, and this heat may be used in the first reactor, advantageously reducing the total amount of hot gas which needs to be supplied to the device 10. Thus more of the total heat supplied by the flue gas is used in the device.
[0045] In some embodiments, one of the reactors such as the second reactor may be positioned at least partially below one of the other reactors to help with the transfer of the heated solid organic material. This may allow for the use of a conveyor which can be positioned generally horizontal. This avoids the need for a connector angled upward which would be forced to compete against gravity. Optionally and as can be seen in Figs., the first reactor 30 and the second reactor 35 each have a cross sectional area which is greater than a cross sectional area of the transfer device, i.e., greater than a cross sectional area of the screw connector 82.
[0046] FIG. 8 shows one embodiment of a pollution control system. Several of the components of the device have been removed for clarity of illustration (such as the second reactors 35). Flue gas plus water vapour and any volatiles or products of volatile combustion are routed from flue gas outlet 72 up to a scrubber 90. Optionally the pipe 97 from the rapid cooling device may also be routed to the scrubber. The scrubber can be one of several different air pollution control devices used to remove some particulates and/or gases from industrial exhaust streams. Traditionally, the term "scrubber" has referred to pollution control devices that use liquid to wash unwanted pollutants from a gas stream. Recently, the term is also used to describe devices that inject a dry reagent or slurry into a dirty exhaust stream to wash out acid gases. Scrubbers are one of the primary devices that control gaseous emissions, especially acid gases. Scrubbers can also be used for heat recovery from hot gases by flue-gas condensation. After the exhaust flue gas is scrubbed, it may be routed to chimney 76.
[0047] FIG. 9 shows a schematic view of another embodiment. With this embodiment, device 110 uses a single reactor 130 for both drying and setting of the solid organic material. A single flue gas generator 140 introduces flue gas into the reactor 130 via connecting pipe 137. Optionally an air inlet 184 may be provided to provide a source of air to flare off volatiles generated during the setting of the solid organic material. Solid organic material may be routed along conveyor 170 to the top of the reactor 130. An input driver such as a hopper and screw conveyor 180 may introduce the solid organic material into the reactor at a solid organic material inlet. As with the first embodiment, the process of upgrading the solid organic material comprises pyrolysis with direct heating followed by quenching. The heating is done in the reactor in a reducing or low oxygen environment. Also as with the first embodiment, rapid cooling of the heated solid organic material is performed by a rapid cooling device 99 such as a quencher which sprays a liquid (typically water and a surfactant) onto the heated solid organic material to form the resulting product. Pollution control devices may be provided in a manner similar to the first embodiment. A controller 149 is operatively connected to the device 110 and in combination with sensors mounted throughout the device, can monitor flow of the solid organic material and flue gas through the reactor, the properties of the solid organic material prior to introduction into the reactor, the properties of the resulting product formed after the heated solid organic material is subject to rapid cooling, and the effectiveness of the pollution control devices.
[0048] FIG. 10 is an isometric view of the reactor 130. Solid organic material is introduced via input driver 180; hot flue gas is introduced below the input driver at flue gas inlet 136, a hopper 150 mounted to the reactor 130 is provided which holds a plurality of t-air flows 160, 161 positioned at right angles to one another, and optionally angled with respect to the ground, as shown. A gap 138 extends between the reactor and the hopper to allow for flue gas to reach the t-air flows in a manner similar to that described in the first reactor 30 of first embodiment.
[0049] Flue gas is low in oxygen and hot. Heat transfer from the flue gas to the solid organic material occurs in the hopper, first driving off water, and then, as the solid organic material heats further, driving off volatiles. Once the solid organic material has been heated for a residence time, output driver, here a screw conveyor 182 removes the solid organic material via solid organic material outlet 134. The screw conveyor continuously transfers the heated solid organic material to the rapid cooling device 99 to form the resulting product. Optionally an additional air inlet 133 may be provided to flare off or combust volatiles released during the heating process, advantageously providing an additional source of heat to the device.
[0050] FIGS. 11 and 12 show cross section views of the reactor 130. Solid organic material is introduced near the top at solid organic material inlet 132. Flue gas flows in a counter direction from flue gas inlet 136 to flue gas outlet 72. The bottom of the hopper 150 narrows along walls 158 to a constriction 157 and the solid material outlet 134 is formed as an additional constriction. Drying zones 152 and 154 are positioned in the hopper above the setting zone 156. The setting zone 156 is positioned beneath the hopper in the reactor adjacent the flue gas inlet. As with the first embodiment, a constriction is present between the drying zone and the setting zone. The drying zone is where the solid organic material initially comes into contact with the flue gas (in the particular reactor in those embodiments with more than one reactor). In the setting zone both solid organic material and hot flue gas are received and mixed, allowing for heat transfer from the flue gas to the solid organic material, usually sufficient to drive volatiles out of the solid organic material. The hopper may be formed of a high temperature steel or alternatively a firebrick or other similar high temperature resistant ceramic material. Similarly, the reactor wall may be formed as a series of layers. The wall can comprise structural steel along with a layer of insulation and a high temperature resistant inner layer such as a high temperature alloy. Suitable materials should be strong enough to withstand the high heat and abrasive conditions of the first chamber. Since the temperature of the first hot gas can exceed 1200° C., the inner layer of the reactor needs to be able to withstand such high heat. Inner layer is shown in this embodiment to comprise a first ceramic material such as a firebrick, insulating castable or other similar high temperature stable material. When the inner layer is a firebrick or nonmetal material, an additional layer of a ceramic paper may be used to help connect the firebricks together.
[0051] FIGS. 13-14 show another embodiment of a device 210 for upgrading solid organic materials. Instead of the embodiment of FIG. 1 where the reactor comprises a dryer and a pair of setters in parallel, here the reactor comprises a dryer 230 and a pair of setters 235, 335 in series. The solid organic material is continuously introduced via conveyor 70 to input driver 280 into the dryer 230, as indicated by the arrow between 70 and 280. The dryer contains gas flow elements (65, 67, either or both or more). The gas flow elements 65, 67 operate in a manner analogous to those shown in the embodiment of FIG. 2, and such controlled mixing of the flue gas and the solid organic material serve to enhance heat transfer from the hot flue gas to the solid organic material while shunting the solid organic material away from entering the flue gas inlet(s) supplying the hot flue gas. When the solid organic material is introduced to both the dryers and the setters via the top, the t-air flows shaped like a upside down "V", for example, or roof shaped work to ensure that the solid organic material flows around the t-air flow and not into it as the solid organic material works it way down through the corresponding dryer or setter. After the solid organic material is heated in the dryer 230 for a predetermined period of time (for example, 5-20 minutes) the solid organic material is continuously removed via dryer solid organic material outlet 234 only to first setter 235 (and not to both setters in parallel). After the solid organic material is heated in the first setter 235 for a predetermined period of time (for example, 10-40 minutes), the solid organic material is routed via first setter solid organic material outlet 289 to the second setter 335. After the solid organic material is heated in the second setter 335 for a predetermined period of time (for example, 10-40 minutes), the solid organic material is routed via second setter solid organic material outlet 389 to be cooled at second setter output driver 286 and continuously routed away from the device 210 via the conveyor assembly 73, 75 in a manner similar to the embodiment of FIG. 1. Total time in the reactor (dryer, first setter, second setter) can comprise 10-60 minutes, for example, depending on how much upgrading of the solid organic material is desired. Input drivers 280, 283 and 284, working in combination with output drivers 282, 285 and 286, continuously move the solid organic material to and from the dryer and setters. The drivers may comprise screw drives and conveyor belts in a manner similar to the drivers in the previous embodiments.
[0052] The flue gas is routed in a flow counter the solid organic material, from flue gas generators 40 through the setters 335 and 235, via connective piping 279 and 233 to the dryer 230, and from there to flue gas outlet 272 (as shown by arrows). In this embodiment, a pair of flue gas generators are used at the second setter 335, and a single flue gas generator is used at the first setter 235. Controller 249 is operatively connected to the device 210 and can control all aspects of the device in a manner similar to the embodiment of FIG. 1, including rate of transfer of solid organic material into the reactors by the input drivers, rate of transfer out of the reactors by the output drivers, rate of flue gas introduced to the reactors, rate delivery of the solid organic material on the conveyor belts, etc. Sensors including temperature sensors may be positioned within the reactors to monitor conditions, and the data generated by the sensors may be routed to the controller and used to help ensure high quality and consistent upgrading of the solid organic material. The controller can be programmed to turn off the heat source at specific temperatures, for example, or to introduce additional hot gases as needed, to help provide controlled production of the resulting product.
[0053] FIG. 14 shows treatment of the exhaust flue gas from flue gas outlet 272 to chimney 276. Since the exhaust flue gas contains some dried and/or upgraded organic material in the form of dust, a cyclone 298 is provided to capture some of the fine particles of dried and/or upgraded solid organic material present in the exhaust flue gas. Such material can be used as a fuel source for the flue gas generators 40, for example. From there, the exhaust flue gas may be routed via connecting pipe 274 to a scrubber 290 in a manner similar to the embodiment of FIG. 1.
[0054] FIGS. 15 and 16 show additional optional embodiments. In FIG. 15, the device 310 comprises a dryer 330, and three setters 345, 355, and 365 all connected in series. This design may allow for the process to be split up into more stages, potentially allowing for better control of the process in some instances. Four flue gas generators 40 are used. Two at third setter 365, and one each at first setter 345 and second setter 365. FIG. 16 shows another embodiment where the device 410 routes solid organic material through a first dryer 430, followed by a first setter 435, followed by a second dryer 530 and lastly a second setter 535. Four flue gas generators 40 are used, two at each of the setters 435, 535. For each of these two embodiments, the other components would be similar to the earlier described embodiments. For example, the dryer or dryers contain gas flow elements such as t-air flows, allowing for enhanced and more diffused heat transfer to the solid organic material. Other embodiments of the device can comprise, for example, more than one dryer (with corresponding gas flow elements) may be used exclusively, or may be used in conjunction with one or more setters (which do not have the gas flow elements).
[0055] From the foregoing disclosure and detailed description of certain embodiments, it will be apparent that various modifications, additions and other alternative embodiments are possible without departing from the true scope and spirit of the invention. The embodiments discussed were chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to use the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled.
User Contributions:
Comment about this patent or add new information about this topic: