MXPA99006353A - A reactor - Google Patents

Abstract

A reactor (20) and a process for upgrading solid materials, such as coal, having low thermal conductivity are disclosed. The reactor includes an outer shell (10) that defines an internal volume for retaining a packed bed of solid materials to be treated and a plurality of plates (12a to 12h) of a thermally conductive material positioned within the internal volume. Each plate includes one or more passageways (14a to 14h) through which a heat transfer fluid can flow. In use, each plate defines one or more thermally conductive bypass or bypasses between the heat transfer fluid and the solid materials in the region of the plate so that in use substantially all of the solids are heated or cooled to a desired temperature range by heat exchange between the heat transfer fluid and the solids via the plates.

Description

REACTOR The present invention relates to a reactor for use in a process, especially a high pressure process, where it is necessary to transfer heat to a low thermal conductivity load of material containing solids such as, for example, coal, or well from a load of said material. The present invention also relates to the process. Several industrial processes require that a load of material containing solids be heated or cooled in order to initiate and sustain a chemical reaction or physical changes. Typically, it is necessary to heat the charge to a high temperature for either the chemical reaction or the physical change to occur. Unfortunately, many loads of solid materials have very low thermal conductivities and it is difficult to heat such material loads by indirect heat exchange. Such charges are often heated by direct heat exchange, for example, by passing hot gases through the charge of solids. As used in this specification, "direct heat exchange" refers to heat exchange processes where a heat transfer fluid comes into direct contact with the material to be heated or cooled and "indirect heat exchange" refers to heat exchange processes in which the heat exchange fluid is separated from the material being heated or cooled by a physical barrier, such as the wall of a tube. Some processes do not lend themselves to direct heat transfer or are not suitable for direct heat transfer. The thermal capacitance ratio between solids and gases is such that large volumes of gas or fluid are required to transfer the heat. For example, the flow of large volumes of gas that is required for the transfer of heat through a filled bed is not possible unless the bed is very thick or unless there are very large heating and cooling times. . In the case of processes involving coal or other materials that contain substances that can be volatile at elevated temperatures, a direct transfer of heat can result in volatile materials expelled with the heating gas which could cause difficulties in cleaning the Exhaust gas before the emission of exhaust gas through the chimney. In other processes, direct heat exchange can cause difficulties in the handling of solids or maintenance problems caused by solids carried in gas streams. In processes of this type, it is necessary to use an indirect heat exchange to heat the charge of solids. A known process of indirect heat exchange is the improvement of coal, particularly low-range coal, by the simultaneous application of temperature and pressure in accordance with that described in U.S. Patent No. 5,290,523 to Koppelman. In this process, the heating of a coal charge under high pressure results in removal of water from the coal by a crushing reaction caused by structural realignment of the coal and also by decarboxylation reactions. In addition, some soluble ash-forming components are also removed from the coal. This results in an improvement of the coal by thermal removal of water and improvement of the calorific value of the coal. By keeping the pressure high enough during the improvement process, the vaporization of the removed water is substantially avoided, which reduces the energy requirement of the process. In addition, by-product water is produced mainly in the form of a liquid instead of being produced in the form of vapor. Thermal processing of the coal requires heat transfer to the coal, (typically 300 to 600 Btu / lb), but the effective thermal conductivity of the coal-filled bed is approximately 0.1 W / mK, which makes the carbon bed a good thermal insulator. One option that can be considered to accelerate the heating of the coal is to provide a process that achieves a reasonable heating time of a carbon bed, which includes: The increase of the thermal drive force by increasing the temperature of the thermal transfer medium. This tends to cause the devolatilization of the coal which, in the case of the low-range coal improvement, reduces the heating values of the product. In addition, this also causes the condensation of tars and other volatilized materials in other parts of the reactor system. - Use of fluid beds. This causes the need to circulate large volumes of gas (inert) which again accentuates the problem of the devolatilization of coal. This also requires the cooling and cleaning of the gas before recompression or the operation of a hot dirty compressor, which in both cases involves capital and maintenance. - Use of stirred beds such as a rotary oven. The operation of reactors of this type at high pressures, with inert atmosphere, includes difficulties and important engineering expenses. An indirect heat exchange is preferred, but this further complicates engineering difficulties and the volume of carbon in the reactor may be low.

- The use of instant drying of a milled feed. This requires subsequent agglomeration to produce a marketable product. An inert gas is also required for heat exchange and the reagent volumes tend to be large due to the dispersed state of the solids. The hydrothermal removal of the coal where the coal is ground into small particles and mixed with water to form a paste and the pulp is subsequently heated to an elevated temperature under high pressure to maintain liquid conditions. This process requires the grinding of coal that must subsequently agglomerate or be used directly in a process such as an energy production station. In addition, the mass of water heated to high temperature is large and this requires large heat exchangers for heat recovery. With the simultaneous application of a high pressure (above 10 barg), each of the above mentioned options becomes more complicated. A filled bed combined with an indirect heat transfer is preferred for coal processing by heating or cooling the bed material due to the minimization of loss of volatile substances, decreased energy consumption, and the production of most byproducts in the form of liquid. A filled bed also allows a wider range of carbon sizes, and thicker carbon sizes which could be preferred for a fluid bed operation. A filled bed also provides the lowest volume in a high pressure reactor, provided that the heating rates are high. A small reactor volume causes savings in terms of pressurization time and reactor costs. The classical approach to increasing indirect heat exchange is to provide a sufficient surface area between the heating medium and the load to be heated. This brings us to groups of tubes, with a heating medium either on the inside or on the outside of the tubes. Such groups of tubes can appropriately transfer heat to liquids and gases (although they have a tendency to form scale and build up, and therefore require maintenance), but present some limitations when used to heat solids. This is particularly the case when solids comprise coal that can have a particle size of up to 19 mm (0.75 inch), or even in the case of export-sized coal having particle sizes up to 50 mm (2 inches) ) when problems of bridging and agglomeration are encountered. Any heat exchange system for materials of this type should be designed to allow a free flow of solids, either at the beginning and at the end of a cycle of a batch process, or during a continuous process. A further difficulty with the prior art hull and tube arrangements described above arises from the fact that most prior art reactors require a discharge cone positioned at the lower end of the set of tubes in the reactor with the object to discharge the coal from the reactor. It is impossible to have a group of tubes that extend into the discharge cone and consequently the appreciable volume of carbon contained in the discharge cone is not heated by the set of tubes. To overcome this difficulty, certain processes incorporate water injection or steam injection into the coal bed. These are known as fluid work. Such working fluids can be vaporized (if liquid) and superheated in the upper sections of the bed and then flowed to the outlet in the lower part of the discharge cone. Cold solids in the discharge cone are heated to form by the working fluid (by convection and possibly by condensation of the working fluid). Nevertheless, the injection of a working fluid has serious consequences for the use of energy of the process. A prior art process employs a helmet and tube type heat exchange apparatus wherein the coal is fed on the side of the tube and a heat transfer oil flows through the helmet side. The tubes typically have a diameter of 75 mm (3 inches) which means that the maximum distance for heat transfer is approximately 38 millimeters (1 inch and a half), that is, the distance from the tube wall to the center of the tube. tube. Although diameter tubes have advantages when operating at high pressures, such reactors are not ideal because it can be difficult to get solids to flow through the tubes. In addition, short circuits and channeling of helmet-side heat transfer oil can occur (resulting in incomplete processing of the coal) and the design of the reactor is complex and difficult to manage from an engineering perspective. In particular, the end plates for the group of tubes are difficult to construct and are thick and expensive components. The volume occupied by coal in reactors of this type is typically only 30-50% of the total volume of the reactor. The present inventors have now designed a reactor suitable for use in the improvement of coal, and also suitable for use in any process in which it is necessary to transfer heat to a charge of solid material having a low thermal conductivity or from of said cargo. The reactor uses the process concept of a conductive derivation. In accordance with the present invention a reactor is supplied for use in a process in which a charge of solid-containing material is supplied to the reactor and forms a bed filled with solids in the reactor and subjected to heat transfer to heat or cooling the charge, the charge has a low thermal conductivity, said reactor includes an outer shell defining an internal volume for the filled bed and a plurality of plates of thermally conductive material positioned within the internal volume, and each plate includes one or several passages through which a heat transfer fluid can flow, and each plate in use defines one or more thermally conductive shunts between the heat transfer fluid and the solids in the region of the plate such that, in use, substantially all solids are heated or cooled within a desired temperature range by the heat exchange between the transfer fluid Resistance of heat and solids through the plates. The reactor of the present invention was developed after studies by the present inventors on the improvement of coal. These studies found that there was minimal resistance to heat transfer on the heat transfer fluid side of the reactor and that the heat transfer limitation was mainly on the coal side. Then, surprisingly, it was found that by inserting an additional resistance to the heat transfer between the heat transfer fluid side and the carbon side, it was possible to operate the process with an improved reactor design. The basis of the invention is the use of a conductive shunt (i.e., a thermally conductive shunt) between the heat transfer fluid side and the carbon side which minimizes the length of the heat transfer path in the coal. As described above, according to the present invention, each plate defines one or more conductive branches between the heat transfer fluid and the solids in the region of the plate. The maximum heat transfer distance is an important parameter in the transfer of unbalanced solids state heat, and particularly in a bed filled with solids. The time to heating and the time to cooling depends critically on the maximum heat transfer distance, as experts in the field know. The design of heated or cooled plates allows a carbon bed configuration with a maximum heat transfer distance to be maintained at a carefully optimized value throughout the carbon bed. At the same time the use of a conductive bypass allows the heat transfer area of the supply side in contact with the heat transfer fluid to be kept to a minimum. The advantages that derive from a minimum volume of heat transfer fluid include optimized flow, better reactor volume occupancy by the filled bed, and optimal heat transfer on the supply side. A minimum volume of heat transfer fluid also has advantages when designed for a possible break between the heat transfer fluid and the container volume under pressure. The use of the reactor of the present invention the heat exchange is observed between the heat transfer fluid flowing through the passages in the plates and the plates by thermal conduction. This heat transfer alters the temperature of the plates. Temperature transfer occurs between the outer surfaces of the plates and the material charge. The conductive shunt, as employed in the present invention allows the heat transfer distances to be optimized on both the supply side and the side of the coal bed, and allows to minimize the maximum heat transfer distance in the bed without increasing the amount of heat transfer fluid or the heat transfer surface of the supply side in the coal bed. Throughout this specification, the term "plate" refers to encompass any three-dimensional shape that has an extension in a dimension substantially smaller than the extent of the other two dimensions, eg, a plate may include a flat plate, or an annular plate or a cylindrical plate In all this specification, the term "filled bed" is understood to mean that the particles in the bed are in contact with each other. It will be noted that the term "filled bed" does not exclude a movement of the particles in the reactor containing the filled bed - provided the particles remain in contact. It will also be noted that the term "filled bed" does not exclude localized movement of particles within a generally static bed. In the case of coal, typically the term "filled bed" means that the bulk density of the bed is 600 to 800 kg / m 3 Preferably, the reactor includes an input means for introducing the load into the reactor and a output means for removing the reactor charge Preferably, the plates are positioned in relation to each other in such a way that, in use, the solids can flow between adjacent plates during loading and unloading of the reactor. adjacent are spaced 50-500 mm (2-20 inches), more preferably 75 to 200 mm (3 to 8 inches), and more preferably 75 to 125 mm (3 to 5 inches). The present invention is especially suitable for use in processes operating at high pressure, for example, at pressures of 2 barg (29.4 psi) or more and preferably at pressures of 4 barg or more. high pressure process that require that the external case have a pressure vessel rating. The plates are made from one or more thermally conductive materials. It is preferred that the thermal conductivity of the plates be at least one order of magnitude higher than the thermal conductivity of the material charge in the reactor during operation. In many processes in which solids are processed at elevated pressures, the solids must be maintained under a pressure that is much greater than the pressure required to pump the heat transfer fluid through the passages. For example, in the removal of water from the coal, the heat transfer fluid (which is normally a heat transfer oil) circulates at approximately 150psi (1033 kPa) while the coal is maintained under a pressure of 800 psi (5510 kPa) . Accordingly, it is preferred that the plates in the reactor of the present invention comprise a passage or a small passage number through which the heat transfer fluid can flow. More preferably, the passages have a relatively small diameter or width and the thickness of the walls of the passages is quite large. Expressed slightly differently, it is preferred that the volume of the passages represent a small percentage of the total volume of the plates. This helps ensure that the walls of the passages are strong enough to withstand the pressure differential caused by the pressure difference between the pressure applied on the outside of the plates and the inner part of the passages. In comparison with thermal jackets, the plates used in the reactor of the present invention are strong and can withstand collapse or crushing at elevated temperature. Apart from the passages, it is preferred that the plates are solid. The plates can be made from any material with a suitably high thermal conductivity. It is preferred that the material of construction of the plates be substantially chemically inert to the heat transfer fluid flowing in the passages, the solid material being processed in the reactor, said solid material being in contact with the outer part of the plates, and any gas or liquid in the reactor. It will also be noted that such plates and support devices and supply devices associated with the plates will necessarily have a resistance to erosion and abrasion in relation to the inlet, flow and discharge of carbon. Thermally conductive metals or composites are suitable for use on the plates. Suitable metals include copper, aluminum, stainless steel, and mild steel. Composite materials such as stainless steel coated copper, chromium coated copper, mild steel sprayed with plasma, or cast copper in a thin mild steel coating can also be employed. It will be noted that this list of materials is not exhaustive and that several of the high thermal conductivity materials can be employed in the plates without departing from the scope of the invention. The shape of the plates can vary greatly, even if plates having a rectangular, parallelogram or tapered cross section are preferred. It is also preferred that the outer surfaces of the plates include substantially planar surfaces, although other shapes may also be employed. The plates can be cylindrical plates or annular plates positioned concentrically inside the reactor.

The passages in the plates can be manufactured by machining the passages in the plates (for example, by drilling), either by casting the plates with the formed passages, or by means of any other manufacturing method. A preferred method for the construction of the passages includes casting or rolling or machining to form a channel at the edge of a plate and subsequent welding or otherwise joining another plate with this edge to form the complete plate . The optimal design for the plates depends on the maximum thermal flow required in the reactor. The average thermal flow of the process carried out in the reactor and the variation of the cycle or residence time. It also depends on the construction material of the plates. The plates can be arranged side by side, stacked in layers or stacked end to end. An optimal spacing of the plates will generally be determined by processing requirement on the solids side of the reactor. The passages for the flow of the heat transfer fluid through the plates can be single or multiple in one unit, with flow in either direction, or with flow returning in the same plate or an adjacent plate. If stacked series of plates are employed, the plates may be connected to the source of heat transfer fluid in series or in parallel or the layers may be connected to separate sources of heat transfer fluid. By using stacked layers of plates the temperature can be controlled separately in the layers which is advantageous if zone heating of the reactor is desired. It is also possible to change the heat transfer fluids flowing through the plates. For example, if the process performed in the reactor requires the heating of the charge, followed by cooling of the charge, a hot heat transfer fluid can pass through the plates in order to heat the charge. The heat transfer fluid can then be changed in such a way that a cold heat transfer fluid passes through the plates to cool the plates and the load, due to the minimum volume of the passages in the plates, the first fluid of Heat transfer can be quickly purged from the passages, allowing a relatively rapid change of heat transfer fluid and the thermal bypass (plates) will quickly cool due to good contact between the heat transfer fluid and the high-pass material. Thermal conductivity. The space between adjacent plates effectively defines a flow passage for solids. Accordingly, the space between adjacent plates must be large enough to ensure that no undue blockage or bridging between the plates by the solids occurs. In addition, the space between the plates must be sufficiently small to ensure that adequate heat transfer rates are achieved for all solids between the plates. In the case of solid materials such as coal, which have a very low thermal conductivity, a practical maximum for the spacing between the adjacent plates is 200 mm (8 inches), with a spacing of 100 mm (4 inches) being preferred since in this way, shorter batch times or shorter residence times can be obtained. In a preferred embodiment, the reactor includes a substantially cylindrical portion with the plates arranged in such a way that when viewed in cross-section the plates extend substantially through the cords of the circular cross-section of the cylindrical portion. It is preferred that the plates extend substantially along the length of the cylindrical portion of the reactor. It is also a common practice to orient such reactors such that the longitudinal axis of the cylindrical portion is substantially vertical. Such reactors are also usually equipped with a discharge cone which can comprise up to 20% of the volume of the reactor. It is also preferred that the reactor further include one or more plates positioned within the discharge cone portion of the reactor, said plates include one or several passages for the flow of a heat transfer fluid. The plates in the discharge cone preferably have a suitable shape to avoid blockages in the flow of solids. The plates may have a suitable shape to facilitate the flow of solid or be jumped and yet provide adequate heating or cooling of the solid material in the cone. Many geometries are possible, including radial plates, flow line plates, fingers, side wall plates and bent plates. The plates can be connected to one end of the reactor. In use, the heat transfer fluid is supplied from a source of heat transfer fluid by one or more lines of heat transfer fluid that extend through the outer shell of the reactor to the passages in the plates. Preferably the plates are suspended from an upper part of the reactor. This arrangement is preferred because it minimizes the potential obstruction of the solids flow. It is also possible to connect the plates to a lower part of the reactor and this is suitable if it is desired to have a heat transfer fluid drain from the plates when a heat transfer fluid circulation pump is turned off. The use of this arrangement may be preferred if melted salts are used as a heat transfer fluid since it is helpful to ensure that such salts are drained from the passage in order to avoid potential freezing of the melted salts in the passages. In one embodiment, the plates are preferably connected relatively loose to the reactor. For example, the plates can be suspended by means of chains, or they can be connected in an articulated manner on the wall of the reactor. This arrangement allows the plates to move or they can be displaced or released if a blockage of solids occurs between the plates. The plates can include additional channels through which work fluids or reagents can be added to the bed or through which said working fluids or reagents can be removed from the bed. The outer shell of the reactor may be lined with an insulating material, such as a refractory lining, and possibly a wear protection liner. The use of an insulating lining allows the reduction of the thickness of the helmet and presents the advantages of flanges of operation in cold and improved security as well as a better thermal balance. The reactor may further include input means for supplying gases or liquids to the reactor. The gases or liquids may comprise pressure increasing fluids or working fluids. The reactor may also include exit means for gases or liquids. In the reactor of the present invention, it is possible to separately optimize the heat transfer of the heat transfer fluid side and also the heat transfer of the solids side. Only a relatively small surface area for heat transfer is required on the heat transfer fluid side and this is provided through the passages in the plates. In contrast, a large heat transfer surface area on the solids side is required due to the low thermal conductivity of solids, such as coal, and this large surface area for heat transfer is provided through the external surface of the plates. An optimization separates the heat transfer allows to minimize the volume of heat transfer fluid in inventory which reduces the cost of capital. The inventory reduction can also allow fluids with higher operating temperatures, or the use of less flammable materials. In addition, the heat transfer fluids currently available have a limited life and the minimization of the required volume has an apparent effect on the economy involved in the replacement of the heat transfer fluid. In another aspect, the passages in the plates can be replaced by heating devices to heat the plates. Heating devices of this type may include, for example, electric resistance heaters.

In this regard, instead of using a heat transfer fluid to heat the plates, the heating means heats the plates (and subsequently heats the charge). In another aspect, the heat transfer passages in the plates are conserved and heating means are included to heat the heat transfer fluid in the passages. The reactor of the present invention is suitable for use in high pressure processes used for the treatment of a charge of solid material having a low thermal conductivity. The reactor is especially suitable for use in the improvement of coal. In accordance with the present invention, there is also provided a process for heating or cooling solids having low thermal conductivity in the reactor having an outer shell and a plurality of plates of thermally conductive material positioned inside the outer shell, each one of said plates has one or several passages for the flow of a heat transfer fluid, and each plate defines the use of one or more thermally conductive branches between the heat transfer fluid and the solids in the region of the plate, said method includes the steps of charging the solids in the reactor to form a filled bed in the external case, passing a heat transfer fluid through said passages and heating or sending solids in the filled bed by thermal transfer between the fluid of transfer heat and solids through the plates and remove the solids from the reactor. Preferably, the method includes the step of increasing the bed pressure filled with solids. When the process operates to heat solids, preferably the process also includes the maintenance of the filled bed under conditions of elevated temperature and pressure lifted for a sufficient time to improve the solids. Preferably the solids are thick. In all this specification, the term coarse is understood to mean a particle size greater than 5 mm. Preferably, the process of the present invention is carried out in a batch process. Preferred embodiments of the present invention will be described below with reference to the accompanying drawings in which: Figure 1 shows a cross-sectional view through a mode of a reactor according to the present invention; Figure 2 shows a lateral elevation of an apparatus including the embodiment of the reactor of the present invention illustrated in Figure 1, to remove water from the coal; Figure 3 shows a side view of the discharge cone of the reactor illustrated in Figures 1 and 2, with an arrangement of plates to ensure the processing of the coal in the discharge cone; Figure 4 shows a view similar to figure 3, but with another arrangement of plates; Figure 5 shows a cross-sectional view of the discharge cone showing an arrangement of radial plates in the discharge cone to ensure an arrangement of radial plates in the discharge cone to ensure processing of the coal in the discharge cone; Figure 6 shows alternative plate configurations; and Figure 7 shows a time-temperature profile for points on a rectangular plate subjected to thermal flow associated with the improvement of the coal through the Koppelman process. In Figure 1, the reactor includes an outer hull 10 having a plurality of plates 12a to 12h. Although Figure 1 shows 8 plates in the reactor, it will be noted that a smaller or larger number of plates can be employed. Each plate 12a to 12h includes two channels 14 (a-h), 15 (a-h), through which a heat transfer oil can flow. Referring now to Figure 2, which shows a side elevation of an apparatus for removing water from the coal, the apparatus includes a reactor 20. The reactor 20 has an essentially identical cross section to that illustrated in Figure 1. The reactor 20 has an oil supply and suspension plate 22 positioned in an upper part thereof. The plates 12a-12h are suspended from chains fixed on a series of hooks positioned around the internal periphery of the plate 22. It should be noted that any suitable suspension means and support device can be used to suspend or support the plates in the reactor. The plate 12a is shown in dotted line in figure 1 and, as can be seen, the plate 12a extends along substantially the entire length of the reactor 20. An oil supply line 24 connected to the hot oil supply (not shown) supplies oil to the plates 12a-12h through of multiple arrays (not illustrated). The oil return line 25 returns the oil to the oil supply device.

In a particular embodiment, the reactor 20 is approximately 7 meters long (23 feet) and has a diameter of approximately 1 meter (3.3 feet). The reactor 20 is also equipped with a gas / liquid inlet 50 for introducing a fluid under pressure and / or a working fluid into the reactor. The reactor also has a fluid outlet 51 to remove working fluid and other reactor fluids and an additional fluid outlet 52 to release reactor pressure. In order to facilitate charging the reactor 20 with coal, the reactor 20 includes a feed hopper 25, positioned above and displaced from the top of the reactor 20. A feed hopper 25 may be displaced from the reactor 20 to allow removal of the plates 12a-12h either unitarily or as a whole, for maintenance or replacement purposes. A feed hopper 25 is connected to the reactor 20 through a displacement conduit 26 and the coal flows from the feed hopper 25 through a displaced pipe and into the reactor 20. The displaced pipe 26 includes a valve 26a for control the loading of coal. In use, the carbon flows downward through the flow passages defined by the opposing surfaces of adjacent plates 12a, 12b, etc. and it fills the reactor in the form of a filled bed. The bottom of the reactor 20 is equipped with a discharge cone 27 to allow the discharge of coal from there.

When the reactor 20 is filled with coal, the discharge cone 27 is also filled with carbon. In order to process the coal that fills the discharge cone 27, various arrangements of plates can be employed within the discharge cone. This will be discussed in more detail later. A discharge cone 27 includes a valve 27a and is connected through a discharge channel 26 to a cooling drum 29. In use, after the treatment of the coal, it passes through the discharge channel 28 in the cooling drum 29 where the hot coal is cooled to a temperature of less than about 70 ° C. The cooling drum may be equipped with plate coolers that are essentially similar to the plates illustrated in FIG. 1, with cooling water flowing through the channels in the plates. After cooling to the desired temperature, the processed charcoal is discharged through the bottom outlet 30 via a valve 30a. The cooling plates can be used to raise the steam and to recover heat. The operation of the apparatus illustrated in Figure 2 will be described below. After filling the reactor 20 with carbon, the reactor is sealed and the pressure is increased and hot heat transfer oil is supplied to the channels in the plates 12a, 12b-12h. Hot oil is typically found at a temperature between 350 and 380 ° C (662-716 ° F). It will be noted that different types of coal and other processed solids may require optimum temperatures different from those mentioned above. The hot oil can be supplied to the plates before filling the reactor with carbon, during the filling of the reactor or after filling the reactor with carbon. Due to the high thermal conductivity of the plates 12a, 12b, etc. the plates are heated rapidly to substantially the oil temperature (in subsequent cycles, the plates will already be hot). The heat is transferred after the hot plates to the charcoal. This causes the increase in the temperature of the coal and a swelling or crushing reaction begins as a structural realignment of the carbon pushes the water out of the coal. After the maintenance of the coal in the reactor for a desired period of time, the reactor is vented to lower the reactor pressure and the processed coal is discharged into the cooling drum 29, where it is cooled and subsequently discharged for sale or further processing, as for example, in small bricks. In figures 3 and 4 show side elevations of the discharge cone 27 and a lower portion of the reactor 20 of figure 2, with possible arrangements of plates 12a-12h (illustrated in dotted lines) in the cone to ensure that the carbon in the con is sufficiently heated to an elevated temperature for a sufficient time for complete processing. As shown in Figure 3, the plates 12a-12h extend downwardly in the cone differently, the central plates extending further into the cone. The arrival of Figure 3 ensures that the carbon can flow freely through the cone while ensuring an adequate heat transfer in the carbon in the cone. In figure 4, the plates 12a-12h have a box shape to adapt to the contours of the cone. Again, some of the plates extend more into the cone than other plates in order to ensure that the carbon can flow freely through the cone. Figure 5 shows a plan view of the cone 27. In Figure 5, a series of radial plates 32a to 32h are permanently installed in the cone 27. The plates 32a to 32h can be provided with their own oil supply or they can be fed from an oil line 24 illustrated in FIG. 2. The plates illustrated in FIG. 1 have a transverse cut tapering inwardly from the heating oil channels. However, other cross-sectional plates can be employed and in Figure 6 some alternative cross-sections are illustrated. Figure 6a shows a plate having a wide central section 34 with the oil channel 35 formed in the central section and tapering towards narrow ends 36, 37. Figure 6b shows a plate having a cross-section in general parallelepiped shape. The plate shown in figure b is a relatively small plate. Figure 6c shows a plate 36 having a square oil channel 39 formed in the central part thereof and tapering towards the points 40 and 41. Figure 6d shows a plate configuration generally similar to the configuration observed in figure 1, except that the oil channels 42, 43 are of circular cross-section. Figure 6e shows a plate generally similar to the plate illustrated in Figure 6d but with the oil channels 44, 45 including projections formed inward from the channel in the plate. This is shown more clearly in Figure 6f which shows a plate wider than that shown in Figure 6e and this plate correspondingly has wider oil channels 46, 47. Figure 6g shows a rectangular plate having channels of circular cross cut oil. The reactor design and the plate configurations illustrated in Figures 1 to 6 may be subject to numerous variations. Particularly, the space between the plates 12a-12h may vary in accordance with the conductivity of the material of construction of the plates, the flowability of the solid material fed to the reactor and the residence time required for the reaction. The thickness of the plates can also vary. It has been shown that as the thickness of the plates increases, the "thermal capacitance" of the plates increases and this acts to dampen any temperature drop that may occur during the course of particular reactions. which thicker plates have a greater thermal mass or a higher thermal ballast and can current to damp the enthalpy requirements of the process.The plates 12a-12h can be arranged in such a way that they extend substantially vertically in the reactor (as shown in FIG. Figures 1 and 2, however, the plates can also be positioned in a horizontal or inclined orientation.The plates are preferably arranged in a vertical orientation so that gravity can be used to help discharge the solids from the reactor. It may also be possible to include one or more transverse extensions that extend from the surface of the plates in order to improve The thermal transfer in the solids material, any transverse extension of this type must be arranged in such a way that the obstacle to the flow of solids is minimized. The plates 12a-12h are preferably mounted loosely in the reactor and are preferably connected to only one end of the reactor. For example, the plates may be suspended in chains. Spacers may be required between the plates and the spacers allow preferably some movement of the plates. This arrangement allows the movement of the plates if one of the flow channels between the plates is blocked, such movement can help to remove the blockage. It may also be possible to include means for moving the plates, such as rods, hammers or vibrators. The plates can be removed from the reactor, either unitarily or together, in order to allow the maintenance of the plates or the replacement of the plates. The plates may also include ventilation channels or injection channels in order to allow selective ventilation of the solid material or selective injection of other agents into the bed of solid material. Since the pressure vessel comprising the outer shell of the reactor is now completely independent of the heating devices (apart from the oil inlet and outlet pipes), the container may be lined with an insulating material (such as a liner). refractory) and possibly also a wear protection lining. This makes it possible to maintain the operating temperature of the structural wall and reactor flanges below 100 ° C, which can result in considerable savings in used steel. The external hull of the reactor requires a full pressure, but can be handled in "cold" and therefore can be designed without changing the permissible metal tension by temperature. Figure 7 shows a time-temperature profile for points on a rectangular plate subjected to thermal flow associated with the Koppelman process to improve the carbon. This process is a batch process and, as can be seen from the graph of the thermal flow, the enthalpy requirements of the process vary greatly with the passage of time. The temperature-time profile plotted in the upper part of figure 7 shows that the temperature in the plates changes during the process but that the maximum temperature drop of approximately 40 ° C at time t = 20 minutes still allows a satisfactory process of coal. The temperature in the plates is substantially restored to the initial value at 70 minutes. It will be noted that the cycle time, plate mass, plate spacing and materials can be optimized. The reactor of the present invention has the following advantages compared to the prior art reactors: an increased volume occupancy by the solid material to be processed in the reactor, typically greater than 60% which either increases the production of said reactor either allows the use of a smaller reactor for a required production. - The pressure vessel can work in cold due to the capacity of placing an insulation lining in the container.

- The heating oil volume decreases. - Optimized transfer of oil heat. - Bed of substantially rectangular, semi-solid solids, located between adjacent plates, which allows a better flow of solids. - Discharge cone heating. - Pairing of the oil heat transfer rate during the reaction cycle. - The need for expansion joints in the main container is avoided. - Differential expansion problems in the helmet and heat exchange tube are avoided. - Can be retrofitted in existing hull and tube reactors. - It can be removed for maintenance or modification purposes. - Facilitates the purge of heat transfer fluid and presents the option to change fluids. - Allows additional scaling beyond what can be achieved with plate and tube. Those skilled in the art will note that the invention described herein is susceptible to modifications and variations other than those specifically described. It will be understood that the invention encompasses all variations and modifications that fall within its spirit and scope.

Claims (10)

1. CLAIMS A reactor for use in a process in which a load of material containing solids is supplied to the reactor and forms a bed filled with solids in the reactor and subjected to heat transfer to heat or cool the load, the load has a low thermal conductivity, said reactor includes an external hull that defines an internal volume for the filled bed and a plurality of plates of a thermally conductive material positioned within the internal volume, each plate includes one or several passages through which it can flow a heat transfer fluid, and each plate in use defines one or more thermally conductive shunts between the heat transfer fluid and the solids in the region of the plate such that, in use substantially all solids are heated or cooled at a desired temperature range by means of heat exchange between the heat transfer fluid and the solids through the plates.
2. The reactor defined in claim 1, wherein the outer hull is qualified as a pressure vessel.
3. The reactor defined in claim 1 or claim 2, wherein the plates are positioned in relation to one another so that, in use, the solids can flow between adjacent plates during the loading and unloading of the reactor.
4. The reactor defined in claim 3, wherein the plates are positioned in relation to each other in such a way that the spacing between adjacent plates is sufficiently large to ensure that no undue blockage or bridging occurs between the plates by the plates. solid
5. 5. The reactor defined in claim 4, wherein the space between adjacent plates is from 50 to 500mm.
6. 6. The reactor defined in claim 5, wherein the space between adjacent plates is from 75 to 200 mm.
7. The reactor defined in any of the preceding claims, wherein the thermal conductivity of the plates is at least one order of magnitude greater than the thermal conductivity of the charge in the reactor during operation.
8. The reactor defined in any of the preceding claims, wherein each plate includes a passage only or a small number of passages.
9. 9. The reactor defined in any of the preceding claims, wherein each passage has a relatively small diameter or width. The reactor defined in any of the preceding claims, wherein the total volume of the passage or the passages in each plate is a small percentage of the total volume of the plate. . The reactor defined in any of the preceding claims, wherein the plates have a rectangular, parallelogram, or tapered cross section. . The reactor defined in any of the above reactions, wherein the outer hull includes a substantially cylindrical portion where the plates are arranged in such a way that, when viewed in cross section, the plates extend substantially through the cords of the cross section of the cylindrical portion. The reactor defined in claim 12, wherein the plates extend substantially along the length of the cylindrical portion. The reactor defined in claim 12 or claim 13, wherein the longitudinal axis of the cylindrical portion is substantially vertical. The reactor defined in any of claims 12 to 14, wherein the outer hull further includes a conical discharge portion extending from one end of the cylindrical portion. The reactor defined in claim 15, wherein the discharge portion has an internal volume that is up to 20% of the total internal volume of the outer shell. . The reactor defined in claim 15 or claim 16, wherein said plates extend into the discharge portion. . A process for heating or cooling solids having a low thermal conductivity in a reactor having an outer shell and a plurality of plates of thermally conductive material positioned within the outer shellEach of said plates has one or more passages for the flow of a heat transfer fluid, and each of said plates defines, in use, one or more thermally conductive branches between the heat transfer fluid and solids in the region of the plate, said method includes the steps of charging the solids in the reactor to form a filled bed in the outer hull, the passage of a heat transfer fluid through said passages and the heating or cooling of solids in the filled bed by heat transfer between the heat transfer fluid and solids through the plates, and the removal of the solids from the reactor. The process defined in claim 18 includes the step of increasing the pressure of the bed filled with solids. The process defined in claim 18 or claim 19, when operating to heat solids includes maintaining the filled bed under conditions of elevated temperature and high pressure for a sufficient time to improve the solids. The process defined in claim 19 includes maintaining the solids at an elevated temperature and at an elevated pressure for a period of 15 minutes to one hour. The process defined in claim 20 or claim 21 includes increasing the pressure of the filled bed at a pressure of at least 4 barg. The process defined in any of claims 18 to 22 wherein the solids are coarse. The process defined in any of claims 18 to 23, which includes the operation of the batch-based process. The process defined in any of claims 18 to 24, wherein the solids include carbon.