DEVICE FOR UPGRADING ORGANIC MATERIALS AND RESULTING PRODUCT FIELD OF THE INVENTION [0001] This invention relates to a device for upgrading of organic materials, and more particularly to a device for pyrolysis of low rank coals and a resulting product. BACKGROUND OF THE INVENTION [0002] Organic materials include coals, peat, biomass, garbage, etc. Large quantities of coal, including low rank coal, exist at many places in the world. Organic materials such as low rank coal have been considered as fuel and a source of energy. However, such low rank coal typically contains relatively large amounts of water - on the order of 30-60% by weight. Because of this high water content, and related low energy density, such coals have been commercially unattractive for use in industry, especially when the industry that needs the coal, such as power plants, are located remote from the source of the coal. [0003] Technologies have been developed in an effort to both dry and to pyrolyze such organic materials, upgrading their calorific content. Pyrolysis is the chemical decomposition of organic material at elevated temperatures in low levels or the absence of oxygen. However, known technologies for drying and/or pyrolyzing organic materials are either expensive 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. The physical structure of low-rank coal is understood to be determined by the effect of oxygen functional groups on hydrogen bonding and the role of moisture as a structural component. Phenolic groups provide a framework for hydrogen bonding, whereas carboxyl groups hinder such structuring. Roughly 20% of the total moisture is held tightly by hydrogen bonding and is believed to contribute to structural rigidity in low rank coals, wood and similar low-rank organic materials. The loss of this structure when coal is dried accounts for the problems of friability and dustiness. Dusty coal is difficult to work with for several reasons. These include the fact that the coal dust is prone to move with slight disturbances in the air, so during transportation and use the coal dust can easily spread in a relatively uncontrolled manner. Further, such coal dust is prone to combust too rapidly for many applications. Also coal can undergo spontaneous combustion, especially low rank coal with low water content exposed to a source of oxygen. [0004] Since low rank coals typically have a high water content, it is not economically feasible to mine 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 used to attempt to upgrade the rank of coal often involve the use of additional additives, heating oils, inert gases, diesel fuel, etc. Any and all of these additional materials must be shipped to the coal mine, greatly increasing the costs of operation. [0005] One attempt to upgrade the rank of coal is what is referred to as the briquetting process. With this technology, 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. [0006] US Patent 5,322,530 to Merriam et al discloses another technique for upgrading the rank of coal by use of fluidized beds in a three step process (dryer, pyrolyzer, cooler), A fluidized bed is formed when a quantity of a solid particulate substance (such as coal ground to a very fine particulate) is placed under appropriate conditions to cause a solid/fluid mixture to behave as a fluid. This is achieved by the introduction of a fluid (often an inert gas) through the particulate medium. In Merrriam et al, crushed coal is fed into a fluidized bed dryer and hot gas with low oxygen content is directly introduced to the coal as a drying gas. The gas is a mixture of recycled gas and flue gas from a burner. After drying the coal is sent to a pyrolyzer, another fluidized bed which uses heat from a flue gas to heat the coal to produce tar-like pitch in the vapour state to coat the coal. From the pyrolyzer, the coal is sent to a cooler. The cooler is another fluidized bed which gradually brings the temperature down to above 220°F (104°C). Merriam's fluidized beds are relatively expensive and use a direct heating agent. Such direct heating is difficult to control, and can lead to charring of some of the coal and uneven removal of volatiles. Further, many fluidized bed systems only work with a very narrow range of particle sizes. Too small and the fluid will blow the particles in an uncontrolled manner; too large and the particles will not react in a significant way. Moreover, particles produced by this process still have problems with sufficient hardness, and typically need to be briquetted, with all the attendant cost and complexity noted above. [0007] US Patent 4,668,244 to Nakamura et al discloses another process for upgrading low rank coal. A three step process (drying, carbonizing, and cooling) is disclosed. Coal is introduced into a drying apparatus along with a supplemental inert gas and heated indirectly. Excessive water vapour and tar are exhausted to outside of the system. A separate carbonizing apparatus takes dried coal and carbonizes the coal. From there, a separate cooling absorbing apparatus gradually dissipates heat in the coal from the carbonizing step. While the coal produced by Nakamura et al does have lower water content, the equipment used and the need for

supplemental inert gases makes the overall process relatively expensive, and the resulting coal particles produced by the process will have insufficient hardness. [0008] It would therefore be desirable to provide a device for pyrolysis of organic materials which is of low cost and which generates a resulting product having controllable and consistent properties. SUMMARY OF THE INVENTION [0009] In accordance with a first aspect, a device for upgrading solid organic material comprises a heat source for heating a heat exchange medium, a housing having an inlet, and defining a material passageway adapted to receive the organic material from the inlet, a burner box adjacent the housing and defining a heat exchange medium passageway adapted to receive the heat exchange medium. The organic material is physically separated from the heat exchange medium passageway. A quencher is operatively connected to the material passageway and adapted to apply a quenching agent directly onto the organic material and thereby form a resulting product. The resulting coal product has specific characteristics which can be preselected, including total water content, volatile matter, calorific value and HGI. [0010] 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 pyrolysis of 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 operations. Additional features and advantages of various embodiments will be better understood in view of the detailed description provided below. BRIEF DESCRIPTION OF THE DRAWINGS [001 1] Fig. 1 is a schematic view of a device for upgrading organic materials in accordance with one embodiment. [0012] Fig. 2 is a schematic view of one embodiment for generation of fuel to be used to generate heat to dry and pyrolyze the organic material. [0013] Fig. 3 is a schematic view of a device for upgrading organic materials in accordance with another embodiment, more suited to higher production volumes. [0014] Fig. 4 is a cross section view of the embodiment of Fig. 3. [0015] Fig. 5 is a cross section view taken through a drier firebox of the embodiment of Fig. 3. [0016] Fig. 6 is a cross section view taken through an optional tunnel drier of the embodiment of Fig. 3. [0017] Fig. 7 is an schematic isometric view of an alternate embodiment of device for upgrading organic materials. [0018] Fig. 8 is a side view of the device of Fig. 7. [0019] Fig. 9 is a top view of the device of Fig. 7. [0020] Fig. 10 is a block diagram of a device for upgrading organic material in accordance with another embodiment, optionally incorporating a flash drying stage and/or a flash setting stage. [0021] Fig. 1 1 is a schematic view of a device for upgrading organic material, showing one embodiment with a flash drying stage. [0022] Fig. 12 is an isometric view of a direct heating device in accordance with one embodiment. [0023] Fig. 13 is a cross section view of the direct heating device of Fig. 11 , taken through a fuel inlet. [0024] Fig. 14 is another cross section view of the direct heating device of Fig. 11 , shown facing the fuel inlet. [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 upgradingorganic materials as disclosed here, including, for example, the specific dimensions of the housing 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 features and

embodiments will illustrate the general principles of the invention with reference to a device for upgrading low rank coal, especially low rank coal with low ash and sulfur content. 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 and method for upgrading an organic material such as low rank coal. Substitution of other organic materials, such as biological sources of carbon (trees) or waste materials, is straightforward and will be readily apparent to those skilled in the art given the benefit of this disclosure. Upgrading is understood here to at least refer to increasing the calorific value of the organic material for a given mass, and typically comprises pyrolyzing a significant portion of the organic material. The device comprises at least one heat source 90, an enclosure, a cooling device such as quencher 60, a controller 80 and related equipment. The enclosure can comprise, for example, at least one screw heat exchanger 50 and a burner box 21. The enclosure has a drying zone 20 and a setting zone 30. The heat source heats the feed material in the drying zone, and also heats the feed material in the setting zone. Optionally the heat source can be a single heat source, or a plurality of heat sources. The quencher 60 would be positioned at or after a quality control zone 40. In the embodiment shown in the Figs. 1-2, the enclosure is a single enclosure such as a single screw heat exchanger and both a drier/drying zone and the setting zone are positioned within the single screw heat exchanger. Alternatively, multiple screw heat exchangers may be used, for example, one for the drier and one for the setting zone. Also, for large volume operations, multiple screws may be used concurrently . The device may be run continuously, which is highly advantageous over batch job processing when high volume processing is desired. [0028] The screw heat exchanger comprises a housing 22, an inlet 26 into a material passageway 29, a screw 24 (which can comprise one continuous flange or a plurality of flanges), and an outlet 28. A rotary valve may be positioned at the inlet, the outlet, or both the inlet and outlet to help isolate the material passageway 29 from the outside environment. The housing 22 acts as a drier, as the feed material is dried in the material passageway inside the housing. The housing also acts as a location for setting the feed material, where vplatiles are emitted. At least partially surrounding the housing 22 is a jacket or burner box/firebox 21 which defines a heat exchange medium passageway 23 which is operatively connected to the heat source. In accordance with a highly advantageous feature, heating of the organic material occurs indirectly. This advantageously helps to ensure more even and complete heating of the feed material and avoid excessive drying, especially on the surface of smaller particles. With the screw heat exchanger, organic material is introduced as a feed material into the drier at inlet 26, and the feed material is steadily forced by flanges in response to the rotation of the screw toward the outlet along the material passageway 29. As shown in the Figs., the material passageway has at least a lower portion which is formed as a lower part of a cylindrical tube with a generally semi-circular cross section corresponding to each screw. The lower portion can extend about ½ of a circle, for example. The flanges of the screw extend from a central trunk located along an axis of rotation and extend along the material passageway. The cross section extends from the axis of rotation to an inner wall of the material passageway. The flanges have a width which, in combination with a portion of the central trunk extending from the axis of rotation, is nearly the same but somewhat less (i.e., at least 85%, more preferably, at least 95%) than a radius of the cross section of the lower portion of the material passageway. (Of course, the flange does not extend beyond the inner wall of the material passageway.) Thus, as the screw rotates the flanges push the organic material along the material passageway. The heat is supplied by a heat exchange medium produced by the heat source(s), which can be, for example, exhaust gases from one or more gasification burners 90. These exhaust gases enter the heat exchange medium passageway 23 and heat the burner box/firebox. The heat so supplied heats the burner box but the exhaust gases are physically isolated from the material passageway such that the exhaust gases do not directly contact the feed material in the material passageway. Thus, heating using this combination of elements is indirect. The effect is heating of the feed material occurs by conduction through the housing and black body radiation, and through heat transfer from steam released by the coal, but not by blowing hot gases directly onto the feed material, thereby providing better control of the heating process. Optionally one or more ambient air inlets 41 , 42 may be provided at both the drying zone and the setting zone. Ambient air may be introduced to help regulate temperatures and help ensure that large particles are properly removed of moisture. [0029] As noted above, the heat source 90 can be a gasification burner and the heat exchange medium hot exhaust gases generated by the gasification burner. The burner can use coal as a fuel source. To help reduce non-gaseous products of combustion, the coal used at the burner may be prescreened for size prior to introduction into the material passageway within the housing. Further, upgraded coal fines generated by the device 10 may be used as a source of fuel. Alternatively, as disclosed in Fig. 2, some heat from the burner (or optionally from a separate burner when the heat source is more than one burner) may be used to merely dry the coal in another drier 70, which can comprise, for example, another auger/screw heat exchanger. For drier 70, no setting would be required. Small particles or fines dried by this drier also may be used as a source of fuel in the gasification burner. Thus, where the heat source 90 is a gasification burner adapted to burn coal fines as a fuel source, such coal fines may be generated as part of the resulting product, or can be prescreened from the incoming organic material, segregated and dried using another auger. Other suitable sources of fuel will be readily apparent to those skilled in the art given the benefit of this disclosure. [0030] In accordance with another advantageous feature, the organic material entering the material passageway may be prescreened for size. Preferably the coal introduced at the inlet 26 is of a size no greater than 75 mm, more preferably no greater than 50 mm, and most preferably particles no greater than 30 mm.

Optionally smaller coal fines (e.g., less than 5 or 7 mm) also may be segregated out of the coal introduced at the inlet and either used in the burner or returned to the mine or otherwise used. Although the device and method described herein allow for a wider range of coal particles than would be possible with fluidized bed systems, coal particles that are too large will not be completely heated to a necessary temperature range, and those that are too small are difficult to work with and often not desired by end use customers. [0031] Drying of the feed material occurs in the drying zone 20. Typically low rank coals contain 40-60% water, and water vapour is typically the first component material to be emitted by coal particles in a heating process. The drying zone typically operates at a drying temperature range from ambient to about 400°C, depending on the type of feed material introduced. The exhaust air used may be several hundred degrees warmer. A motor 27 controls auger rotation speed. The length of the auger also can be varied to control the time the feed material is exposed to heat. At a minimum, the temperature of the firebox and the time in the drying zone must be sufficient to evaporate a large percentage of the water present in the feed material. However, it is not necessary to eliminate all water from the feed material. Maximum temperatures are limited by the temperatures of the incoming heat transfer medium. For gasification burners, typical exhaust gas temperatures will not exceed 1600°C, and the exhaust gas is typically mixed with ambient air so as to be introduced into the heat exchange medium passageway at temperatures around 500-800°. Such temperatures can be sufficient for drying and for setting the organic material. [0032] Most of the energy imparted to the feed material at the drying stage is used to liberate water as steam. In accordance with another highly advantageous feature, no additional inert gas in required to be pumped into the housing. Rather, steam and/or superheated steam can be retained in the material passageway of the housing such that an overpressure above atmospheric pressure is maintained. Such overpressure can be above atmospheric and is typically no more than 5 bar, and more typically less than 2 bar. Positive pressure keeps oxygen containing air out of the material passageway, allowing for at least some pyrolysis of the feed material. [0033] At the setting zone 30, further heating occurs. Setting is understood here to normally comprise heating the feed material to a setting temperature range sufficient to emit volatile matter from the feed material. Volatile matter in organic materials such as coal refer 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 steps of drying and setting and the drying and setting zones are not absolutes. Rather, initial heating of the fuel 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 evolve more with further heating, such that principal evolution of volatile matter occurs generally closer to the end of the screw heat exchanger. Thus, in the embodiment shown in Fig. 1 , the drying and setting steps occur within a single screw heat exchanger. The chimneys (25, 35, 31 ) at different locations receive primarily water vapor, primarily volatile matter, or a mixture of water vapor and volatile matter. [0034] When low rank coal is used, the processed resulting product is a coal product of higher rank with properties which can be preselected by the operator on behalf of a customer. The process is highly advantageous over known processes for upgrading the rank of coal, since no additional resin or equipment for briquetting is needed, no additional gases need to be shipped to what is often a remote coal mining site, and the process parameters (temperature range, time in each zone, quenching speed) can be controlled in a straightforward and inexpensive manner. [0035] In accordance with another highly advantageous feature of some

embodiments, at least the step of setting the feed material can occur in an enclosure with a pressurization apparatus pressurized to above atmospheric pressure. In many instances, a longer length of time is required for drying than for setting due to higher energy requirements to evaporate water from the feed material. In those embodiments where drying and setting both occur within the material passageway 29 of a screw heat exchanger 50, a pressure above atmosphere may be maintained at both zones 20, 30 during operation. Advantageously, the pressurization apparatus uses steam and/or superheated steam and volatile matter emitted from the coal feed material as the source of gases for maintaining the overpressure. The pressurization apparatus can comprise the housing 22 of the screw heat exchanger 50 working in combination and any feed material positioned in the material passageway 29, without any additional valves to cap the device, as for many types of organic materials sufficient overpressure may be maintained merely by

continuously introducing more organic materials into the material passageway 29. Thus, the enclosure need not be completely sealed off from the outside environment. Alternatively, at least one valve may be operatively connected to the material passageway to seal the material passageway from the external environment.

Examples include rotary valves at the inlet 26 and outlet 28, and exit 46. Such valves may prevent pressure from returning to atmospheric levels, and may also be adapted to allow gas to be vented from the material passageway when pressure in the material passageway exceeds a predetermined limit. [0036] In addition to the housing and any valves, exhaust ports connected to chimneys may be provided to allow excess steam and/or volatile matter to escape and relieve excessive overpressure. In the embodiment of Fig. 1 a chimney 25 is positioned at the drying zone 20 which would principally emit steam, another chimney 35 may be provided at the setting zone 30, and an additional chimney 31 may be provided closer to the end of the setting zone where a larger portion of volatile matter may be released. Alternatively such volatile matter may be captured for further processing. Optionally ID fans and/or additional valves may be positioned in any of the chimneys and can be used to help maintain overpressure (i.e., above atmospheric pressure) within the housing. The overpressure prevents introduction of significant amounts of ambient air, and thereby advantageously keeps oxygen levels within the housing low. [0037] At the temperatures of the setting temperature range volatile matter is released. Volatile matter emitted by the feed material during the setting step need not be routed away. Instead, it can remain present in the material passageway and help maintain positive or above atmospheric overpressure. Optionally volatile matter generated by the setting step may be routed from the housing through a first port 33 to a link 32 and back to the gasification burner or other heat generation device for burning. [0038] Once the feed material reaches the outlet 28, it can be quite hot, depending in part on the properties of the organic material used. From the outlet, the feed material can be transferred to a quencher 60. A quenching step in a quality control zone 40 occurs at the quencher. Thus, the step of quenching occurs after the step of setting, and the step of setting occurs after the step of drying. Quenching can comprise spraying a quenching agent such as an aqueous liquid directly onto the feed material from the setting step using a device such as a sprayer 43. This causes rapid cooling of the feed material to form a resultant coal 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.

Optionally a surfactant such as Focust™ may be mixed with the water used for quenching, so that a mixture of both may be delivered to the organic material.

Application of such a surfactant is useful for resisting spontaneous combustion and for resisting ingress of water after treatment of the resulting coal product. The quencher 60 can be formed in a single housing with both the drying and setting stages. Alternatively, a separate cooling section 146 may be provided for the quencher. Advantageously, quenching may occur at ambient pressure. [0039] A large quantity of steam is generated during quenching. At least a portion of that steam can be accumulated and routed back to the drying step and/or setting step by a return connector (not shown) connecting the quencher to the screw heat exchanger to help maintain positive pressure of superheated steam. The quencher 60 shown in Fig. 1 is operatively connected to the outlet 28 so as to receive the feed material from the outlet. The quencher 60 can comprise an extension of the screw heat exchanger such that the steps of drying, setting and quenching all occur in a single screw heat exchanger. Alternatively, as shown in Fig. 1 , the step of quenching can occur in the cooling section 146 separate from the screw heat exchanger. Resulting product is forced along by use of an auger/screw 45 driven by motor 47 until it reaches exit 46, and final exit from the device can optionally be controlled by a rotary valve positioned at the exit. [0040] Optionally a controller 80 may be provided. The controller is operatively connected to the device and can control all aspects of the device. The controller can be configured to control the rate of rotation of the screws 24, 44, for example, the amount, if any, of ambient air introduced into the jacket at inlets 41 , 42, and also control the position of valves and operation of fans. Sensors may be positioned within the passageways and connectors to monitor temperature and pressure conditions. Also, the controller may control the heat source to adjust the

temperature of the incoming exhaust gases. The controller can also control flow rates at the sprays. A temperature controller is part of the controller and can control temperature so as to define a drying zone in the material passageway 29 heated to the drying temperature range, and a setting zone in the material passageway heated to the setting temperature range. As noted previously, the setting temperature range is greater than the drying temperature range. [0041] The processed resultant coal 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 can be modified in a controlled manner. HGI is a measurement of the ease with which coal can be pulverized which generally increases with the rank of coal, and ash fusion temperature gives and indication of softening and melting behavior of the ash in the coal. [0042] The resultant coal product has properties which vary depending on the size of the particles and also which vary from a centre of each particle to an exterior of each particle. For example, at least some of the processed resulting coal product, especially the resulting product of relatively large size (closer to 20-30 mm in diameter) will have significant amounts of water remaining, and the amount of water remaining increases closer to the centre. This is due to the fact that the relatively large particles do not conduct heat readily into the centre and consequently do not yield all of their water during heating. Similarly, coal particles will have a

concentration of volatile matter lower near an outermost portion or exterior than at a core portion or centre. Such properties of the resulting coal product act as a fingerprint, helping with identification of coal produced using this process, if needed. Furthermore, water content comprises free moisture and inherent moisture.

Typically it is not desirable to remove all moisture, as such resulting product will have unacceptable low density, which can be a problem with shipping. [0043] The resultant coal product can have some or all of the following properties, as desired: coal particles having an average HGI of 45-60, a particle size in a range between 5 mm and 30 mm, with some of the coal particles being of a larger particle size in the range of 20-30 mm, and some of the coal particles being of a smaller particle size in the range of 5 mm to 6.5 mm. The larger coal particles have a total moisture content which is larger closer to the centre than it is at the exterior, and a reflectance which is lower closer to the centre than it is at the exterior. The change in reflectance is a result of the heating being applied to the surface. Even further hardening can occur by even greater exposure to a heat transfer medium allowing for very rapid cooling, such as submergence in a bath of water. With this option, the HGI in the resulting coal product can be even lower than 45-60, if desired. [0044] The resultant coal particles can also have a calorific value which varies by size of the particle. The smaller particle size has a calorific value that is higher than a calorific value of the larger particle size of the resulting coal product. An amount of dry, ash-free volatile matter of the resulting coal product of the larger particle size can be larger than an amount of dry, ash-free volatile matter of the resulting coal product of the smaller particle size. An amount of oxygen and/or hydrogen of the resulting coal product of the larger particle size is larger than an amount of oxygen of the resulting coal product of the smaller particle size. [0045] The tables below provide examples of the ranges of properties of the resultant coal product that can be produced with a given organic material. The resulting product in each instance has particle diameter or size of largely 5-30 mm.

The examples in the tables below are for several different kinds of starting organic material including a low rank coal such as a lignite, and an intermediate rank coal such as sub-bituminous coal. The resulting products are partially a function of the organic material used as a starting feed material, but also can be tailored beyond the ranges listed, if desired. For example, if very low amounts of moisture are desired in the resulting product, the drying stage can be extended. If lower HGI levels are requested, quenching speed can be increased. Generally, the device and process disclosed herein creates a significant percentage difference between the starting organic material and the resulting product in terms of HGI, calorific value, moisture content, oxygen and hydrogen content, are available in the ranges shown in the tables. In the tables, "daf refers to dry ash free coal, and "ar" refers to as received.

Value (daf)

Calorific 4300 kcal/kg > 7200 kcal/kg > 7200 kcal/kg

Value (ar)

Volatile -48.5% 14.5% 14.5%

Matter (daf) [0046] Figs. 3-6 shows another embodiment of a device for upgrading of organic materials, especially suitable for high volume operations. The heat source comprises a plurality of gasification burners 90 used with at least one burner box/firebox 123. In the embodiment of Figs. 3-6 four gasification burners 90 are used with first burner box 123 at the drying zone, and four more gasification burners 90 are used with second burner box 223 at the setting zone. In this way relatively uniform heating air temperatures may be maintained at each zone. The heat exchange medium passageway is positioned in each burner box, and may optionally be connected together. The organic material, typically coal, would be carried on a conveyor belt 149 to an inlet 126. A pair of screws may be used inside a screw heat exchanger 150, so relatively large volumes of coal can be processed efficiently. Heating of the feed material occurs indirectly, as with the earlier embodiment. Fig. 5 shows a cross section through the drier burner box 123 showing operative connection to the heat exchange medium passageway inside the housing of the screw heat exchanger 150, and from there to the plurality of burners.

[0047] With this embodiment, the quencher is positioned in a quality control zone 140 in the same screw heat exchanger. Thus, drying, setting and quenching can all occur in a single housing. Resultant product coal can be carried away on conveyor belts 59 for shipment to a customer. Alternatively, it may be desirable to dry out the recently quenched coal prior to shipment. In that case, the resultant coal product can be routed onto vibrating screens/conveyor belts 151 , 152 and into an inlet 153 into a separate drier and to outlet 228. The heat source of one or more burners 90 may be linked by a flue connection 177, provide heat to dry the quenched product. A chimney 154 can vent vapor from this last drying stage. Fig. 6 shows a cross section of the inlet 153 to the last stage separate drier and chimney 154. [0048] Since the volume of volatile matter emitted in a large scale process can be large, additional chimneys 125, 135, 145, 155 and 231 can be used, as shown. Optionally, where emitted materials at chimney 231 are largely volatile matter, such volatile matter can be routed to the burner box 223 by a link 91 , while the solid organic material is still physically isolated from the heat exchange medium

passageway. Link 91 effectively connects the housing to the burner box such that volatile matter emitted by the feed material is burned by the heat source, and thereby advantageously use some of what might otherwise be a waste product as a combustible source of heat for operating the device. Valves may be positioned at any or all of the chimneys and at the inlet and outlet as part of the pressurization apparatus. The valves are operatively connected to the material passageway and can vent steam and/or volatile matter from the material passageway when pressure in the material passageway exceeds a predetermined limit. [0049] Fig. 4 also shows that burner boxes 123 and 223 are set at different heights. The housing may expand to different sizes at different places along the screw heat exchanger to allow air previously introduced at earlier stages or to allow for different volumes of air to enter each place of the heat exchange medium passageway. [0050] Fig. 7 shows another embodiment of a device 210 for upgrading solid organic material such as coal suitable for large volume operations. The device is scalable and modular, and so can advantageously be adjusted for different volume operations. The drying zone 220 comprises a plurality (here six) of screw heat exchangers, a setting zone 230 comprises a plurality (here six) of screw heat exchangers, and a quality control zone 240 comprises another plurality (again six) of screw heat exchangers. A separate screw is used with each screw heat exchanger. The drying zone is positioned above the setting zone, and the setting zone is positioned above the quality control zone. As the device is modular, more or less screw heat exchangers may be used at each stage. Each screw heat exchanger has a housing defining the material passageway with a single screw in the material passageway in much the same manner as in the embodiment of Fig. 1. Rotation of the screw urges the solid organic material through the material passageway, providing gradual heating in a controlled manner. Heating is typically increased at each zone. In the embodiment of Fig. 7, a top part of the housing is removed for ease of illustration to reveal the screws. Optionally solid organic material can fall from the drying zone to the setting zone and from the setting zone to the quality control zone, such that three screw heat exchangers, one at each stage or zone, combine to form a single material passageway. As before, the solid organic material is physically isolated from a heat exchange medium passageway, so as to advantageously provide indirect heating of the organic material and provide more uniform resulting upgraded product. [0051] Solid organic material such as coal can be introduced at inlets 226 by conveyor belts 300. For ease of illustration, some of the conveyor belts are not shown in Figs. 7-9. Similarly, after the solid organic material is dried and set it is collected with a collector 260, which can comprise, for example, a screw 265. From there the solid organic material can be routed away from the device via conveyor belts and/or bucket elevators 302. Optionally a screen or other filtering device (not shown) may be positioned after the collector or after the conveyor belts and/or bucket elevators to separate out small (less than 2 mm, for example) upgraded product. Such small upgraded product can advantageously be used as fuel to generate hot exhaust gases (the heat exchange medium) by the heat sources 90. As shown in this embodiment, four heat sources 90 can be used to supply all necessary heat to all screw heat exchangers. The heat sources can be gasification burners which burn fuel and emits principally hot exhaust gas with little particulate matter. When coal is used as a fuel, a pulverizer 340 may be used to ensure particle sizes no greater than a predetermined maximum such as 30 mesh (0.595 mm), for example. This will help ensure more thorough combustion. [0052] The burner box 323 operatively connects all of the burners together and defines the heat exchange medium passageway. Optionally the hot exhaust air from the burners 90 may deposit particulates in the burner box 323 which can be removed intermittently to help reduce the amount of solid products of combustion. As with the other embodiments, the burner box containing the heat exchange medium

passageway is adjacent at least one housing of a screw heat exchanger. That is, a wall of the burner box is next to or part of a wall which defines the heat exchange medium passageway. In this way heat transfer can occur from the heat exchange medium to the solid organic material indirectly, with the wall or walls physically separated the exhaust gas from the solid organic material, and therefore advantageously uniformly heating the solid organic material, generally without the exhaust gas directly contacting the feed material. [0053] In the embodiment of Figs. 7-9, the burner box effectively supplies heat to all 18 screws. The feed organic material is pushed by screws so as to travel through the several zones 220, 230, 240. The feed material may be quenched using a quencher spraying fluid directly onto the feed material to form a resulting product in a similar manner as discussed above. The burner box 323 can be operatively connected to an exhaust port or flue gas stack 290 to vent exhaust gas. The exhaust port may be operatively connected to a turbine, such that waste heat can be used to generate electricity. Alternatively, the order of the device 210 and a turbine may be reversed. Generally, exhaust gases from the burners may be used in the most efficient manner to capture a large amount of the heat from the exhaust gas. Typically, exhaust gas from the heat sources 90 transfers their heat indirectly to the organic material, liberating emissions such as steam and volatiles. Chimneys 225, 235 and 245 may be provided at each stage to vent these emissions from the solid organic material. Alternatively, emissions generated as a result of the process can be at least partially captured. For example, at the drying stage, steam is mostly emitted. Such steam can be captured, filtered and purified, and/or put to work in a steam turbine to generate electricity. Generally, such water may be collected and used as desired. Any of the aforementioned embodiments may be used in combination with a steam turbine and generator. Further, volatiles (which primarily tend to be emitted at the higher temperatures of the later setting zone 230 and quality control zone 240) may be captured and processed as well. [0054] As with the other embodiments, optionally air may be introduced into the material passageways and/or the heat exchange medium passageways at one or more locations. For example, air can be introduced at the end of the quality control zone 240, if needed. From there, the product is quenched in or after the collector 260 and then routed away on conveyor belts and/or bucket elevators 302. The quencher can comprise spraying a quenching agent such as an aqueous liquid, optionally including a surfactant. [0055] A controller 280 can be provided which, in a manner similar to the controller of the other embodiments, can control motors which rotate the screws, and pulverizers 340 as well as a rate of introduction of fuel into the burners 90. The controller may also control rate of application of the quenching agent, and rate of speed of the conveyor belts and related assemblies 300, 302, as needed, so that all elements of the device function together to ensure continuous upgrading of low rank organic materials. [0056] In certain embodiments it may be desirable to rapidly dry the incoming organic material, especially when large amounts of water are present in the fuel. Although drying can be done using the indirect heating devices discussed above, an additional, faster or flash drying stage may be provided. Fig. 10 shows an

embodiment of a device 810 for upgrading organic material where a direct heating device is used first on the organic material in a flash drying stage 820. That is, the direct heating device heats the solid organic material prior to introduction into to a material passageway of an indirect heating device. Such a direct heating device can comprise, for example, one of a fluidized bed reactor, a rotary kiln, a microwave generation device or a gasification dryer, for example. The direct heating device is particularly advantageous for organic materials such as coal with greater than 40% total moisture. The direct heating device can operate at temperatures greater than 1000°C, for example, or more preferably at temperatures of 600°C to 900°C. Wet organic material which would otherwise be difficult to work with can be retained in the direct heating device for a limited period of time, depending on the water content and related properties of the solid organic material. Generally, the time spent in the direct heating device will rapidly drive off excess water, reducing total moisture to 30- 35% by weight. Advantageously, this is done without evolution of significant portions of volatiles, since continued rapid heating at high temperatures will adversely affect the resultant properties of the final product, such as by creating excessive amounts of undesirable coal fines, for example. [0057] After the flash drying stage 820, the organic material may be routed to a drying and setting stage 830. This can comprise an indirect heating device such as those discussed above in the earlier embodiments. Organic material can be present in the indirect heating device for less than 10 minutes, for example, and can have its total moisture reduced from 30-35% down to 15-25%, for example. From there, the organic material may be routed to the collector 850 where the temperature of the organic material is rapidly reduced in a manner similar or the same as discussed above in the other embodiments. The organic material may stay at the quenching stage for one minute or less; the period of time would be less than that which would cause combustion at the higher operating temperatures. Optionally, a flash setting stage 840 may be provided, after the drying and setting stage 830 and also before the quenching stage 850. The flash drying stage can use a second direct heating device to apply heat to the organic material for a short period of time, for example, 2 minutes or less. Since the temperature of the solid organic material at this stage in the process is already relatively high, further heating causes rapid evacuation of some amount of volatile matter and additional reduction in total moisture. Such a device may be used in those embodiments where the flash drying and indirect heating are insufficient to produce the desired properties in the resulting product. One advantage of these embodiments is that overall process time is significantly reduced, allowing for higher throughput or organic material. Another advantage of these embodiments is that one or more rows of screw heat exchangers may not be required to upgrade the organic material into a resulting product with the desired preselected properties. [0058] Fig. 1 1 shows one embodiment of a device 810 for upgrading organic materials where a flash drying stage 820 is used. The direct heating device comprises a vertical gasification burner operatively connected to a vertical dryer 790. After the organic material is partially dried in the dryer, the organic material is sent to inlets of a housing via conveyors 825, 826 and from there into a material

passageway for indirect heating, optionally by use of one or more screw heat exchangers as shown above. In accordance with a highly advantageous feature of this embodiment, if sufficient drying occurs in the flash drying stage, then a single row of screw heat exchangers can be used. In the embodiment of Fig. 1 1 a flash setting stage is not present. However, one can be operatively connected between the outlet of the housing of the indirect heating device and the quenching stage 850 if required. [0059] Figs. 12-14 show one embodiment of a direct heating device suitable for use as part of the flash drying stage and/or the flash setting stage. Here, the direct heating device is a vertical dryer 790 comprising an inlet 792 for the solid organic material which can have, for example, a screw drive to urge material into the dryer, an inlet 791 for a flue gas, typically heated to temperatures above 1000°C (for either the direct heating device used at the flash drying stage or the flash setting stage), optionally one or more inlets 793, 795 for ambient air (and/or flue gas in some embodiments, if required) and an exit 794 at the bottom for the solid organic material. In operation, the hot flue gas may be exhaust gas from a burner burning coal fines, for example, and the flue gas comes into direct contact with the solid organic material, transferring heat and liberating steam. The direct heating device may be operatively connected to the inlet of an indirect heating device. [0060] When both the flash drying stage 820 and the flash setting stage 840 are present a second direct heating device can be the same as the first heating device - a second vertical dryer, for example. The second direct heating device can use the same heat source as the first direct heating device, or an alternate source of heat. Typically the second direct heating source would be operatively connected between the material passageway and the quencher. [0061] 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.