RU2663425C1 - Method of electrothermal processing of particulates in fluidized bed and device for its implementation - Google Patents

Abstract

FIELD: technological processes.SUBSTANCE: invention relates to a method for the electrothermal processing of a particulate material in a fluidized bed and an apparatus for carrying it out. Method includes feeding gas through the bed of particulate material in an upflow stream, providing fluidization of the bed, and passing an electric current therethrough, while further mixing the particulate material in a fluidized bed by separating the feed gas stream into jets, which are directed at an angle to each other, or by changing the spatial distribution of the electric current density. Device comprises a lined vessel with a gas distribution and supply system and electrodes, one of which is mounted vertically in the vessel, immersed in a fluidized bed, and is provided with an axial channel. Gas distribution and supply system is made in the form of branches, one of which is connected to the axial channel of said electrode. Lining of the vessel in the lower part is made in the form of a bowl, in which there are channels connected to the system of distribution and supply of the gas flow.EFFECT: invention provides an increase in the uniformity of the distribution of particulate material in the fluidized bed, as well as an increase in the technological and energy efficiency of the processing of dispersed materials.30 cl, 6 dwg

Description

The claimed technical solution relates to electrical technology, in particular to technology and equipment for the processing of dispersed materials.

A known method of processing dispersed material, in which the starting components are mixed (quartz sand and petroleum coke fines), is fed into an electrothermal fluidized bed furnace, an electric current is passed through the mixed components and subjected to (high-energy) heat treatment in the solid phase at a temperature of 1800-2000 ° C providing heat and mass transfer and chemical reactions in a fluidized bed, dispersed silicon-containing material is obtained (1).

The disadvantage of this method is that it does not provide effective fluidization of the dispersed material and the uniformity of its heat treatment under the action of an electric current flowing through it. As the dispersed material is heated, for example, to an operating temperature of 1800-2000 ° C, the gas flow rate in the electrothermal fluidized bed increases several times. This is due to both an increase in the volume of the gas and the formation of gaseous substances (CO, SiO) under the indicated heating. The fluidized bed has instability associated with the formation of gas bubbles and their rise to an open surface, accompanied by an increase in the volume of bubbles and their opening on the surface. When the bubbles open, particles of dispersed material are ejected upward, which can be carried out of the furnace by an outgoing gas stream. When a fluidized bed is heated, the instability of its fluidization increases.

Dispersed particles, displaced from the volume of rising bubbles, form seals and clumps in the fluidized bed, which create higher hydraulic resistance to the upward flow of gas and increase the unevenness of fluidization. The unevenness is further enhanced by the flow of current, the density of which increases in the seals, which leads to uneven release of power throughout the furnace. As a result of a combination of these factors, conditions arise for the coalescence of bubbles and the formation of gas jets, the hydraulic resistance of which is lower than in neighboring denser zones of the layer, which leads to disruption of the fluidization process. These shortcomings reduce the yield, increase the consumption of electricity and materials, worsen the quality of the resulting product due to deviation of the temperature of individual zones from the optimal heat treatment temperature and worsen the flow of chemical reactions between the components loaded into the furnace.

There is a method of firing fine-grained material, which is loaded into a fluidized bed furnace, air is supplied through a gas distribution grid, and torches of fuel burners are directed into the furnace tangentially to the cylindrical wall of the furnace at different angles of the fuel spray nozzles (2).

The supply of the fuel mixture into the furnace tangentially to the cylindrical wall of the furnace causes gas flow turbulence in the zone of installation of the burners, which somewhat improves the uniformity of the processes occurring in the working volume of the furnace compared to the previous solution. But, in relation to the electrothermal processing of dispersed material, this solution is ineffective. Firstly, the use of fuel burners leads to the fact that the atmosphere in the furnace becomes oxidizing, which will lead to the rapid destruction of the electrodes used for the electrothermal processing of dispersed material. Secondly, an additional (to the gas distribution grid) gas supply system through the side cylindrical wall complicates the design and does not provide gas flow turbulization in the furnace levels located below the burners. Thirdly, in the intervals between the burners, intensification of mixing of the gas flow does not occur. Therefore, the disadvantages of the previous method in this solution are partially reduced, but not eliminated. New problems have appeared that impede the introduction of electric power into the fluidized bed.

A known method of processing in a vessel with an electrothermal fluidized bed of a dispersed material consisting of two components - volatile and highly volatile, in which the said components are fed into a vessel with two coaxially mounted hollow electrodes. The heavy volatile component is fed through the cavity of the internal electrode into the space under the gas distribution grid, where it is mixed with the volatile component, from there the mixture of components is fed into the working space of the vessel through the distribution grid, and the reaction products are removed from the upper part of the vessel (3).

In this solution, through an opening in the central electrode, one of the components of the dispersed material is fed into the sublattice space. The volatile component is also fed into the sublattice space, which in this case is part of the distribution system for the flow of volatile reagents. There, this component is mixed with another component. In the working part of the reactor is fed a total stream of a mixture of components. Since the finished mixture is fed into the workspace through the grill, in this solution all the above-mentioned disadvantages of the first method are preserved.

A known method of electroslag remelting, in which through the electrodes, as well as between the materials passing electric current of low frequency. The power that is released near different electrodes is redistributed, changes the modulation depth and / or frequency of the current flowing between the various electrodes (4).

This method provides mixing of the liquid metal bath due to the electromagnetic interaction of the low frequency current components (less than 50 Hz) having different directions in the working space. The required intensity and nature of electromagnetic mixing is achieved by adjusting the frequency of the current and / or the depth of its modulation. Despite the difference between the operations and processes implemented in this method compared to the proposed solution, one can see some analogy of the electrohydrodynamic processes in the bath of a liquid electrically conductive melt and the electrodynamic effect on the fluidized bed of an electric current flowing through it. In analogue, a positive effect is expressed in the redistribution of power on the electrodes immersed in the melt by adjusting the frequency of the current and / or the shape of its curve, which leads to a change in the characteristics of the spatial distribution of current density. In relation to the electrothermal fluidized bed, this method does not create the desired beneficial effect, which is expressed in increasing the uniformity of the layer.

There is a method in which the rotation of the electric arc, burning in the gap between two heated and melted ends of the pipes, is ensured in a magnetic field created by the current flowing through the coils that enclose the ends of the pipes, thereby achieving the fusion of the protruding sections at the ends of the pipes and increasing the uniformity of their heating (5). The electric arc moves around the circumference as a result of the electrodynamic interaction of intersecting vectors of the arc current density with the vectors of the magnetic field created by the coils. In the electrothermal fluidized bed there is no electric arc and this method does not create a positive effect.

Closest to the claimed is a method for producing finely dispersed silicon carbide, comprising introducing into the sealed vessel a mixture of the initial dispersed carbon-containing and silicon-containing components, supplying an inert gas to the vessel, providing fluidization of the dispersed materials and passing electric current through them. In accordance with this method, it is required to provide the ratio of particle sizes of each component specified by the equation, taking into account their density and Archimedes number (6).

This solution, in comparison with method (3), the processing of dispersed material is improved in that the components of the dispersed material are pre-selected according to grain size and mixed, which allows to increase the uniformity of distribution of the ratio of components in the working volume of the vessel. To ensure the effective flow of the interaction of the components, this is not enough. It is also required to ensure uniform distribution over the volume of the mixture, preventing the formation of zones with a reduced and increased concentration of dispersed particles. This problem is not solved in this method, as well as in method (1).

A device is known that contains a cylindrical vessel with a distribution system for the gas supplied to the vessel, made in the form of a gas distribution grill and a source of sound vibrations located under it, a bulk material loading unit and a pipe for removing the finished product (7).

The source of sound vibrations located under the gas distribution grill is not effective enough to introduce disturbances into the volume of the fluidized bed since the channel cross-section is a small part of the gas distribution grid area. Sound vibrations that have passed through the gas distribution grill (which acts as a filter in this case) are partially reflected from the fluidized bed, and the rest of the sound vibrations are damped in areas of the fluidized bed adjacent to the gas distribution grill. The sound source does not affect the bulk of the fluidized bed.

A device is known, which is a vessel, inside the body of which, containing nozzles for introducing volatile components, a gas distribution grid and two coaxially mounted hollow electrodes are placed (3). The inner electrode is mounted on the gas distribution grid, and its cavity communicates with the sublattice space. In this device, the distribution system of volatile components is divided into branches. The disadvantage of this device is that the volatile component supply system, made in the form of a gas distribution grid, is common to the mixture of components, which keeps uneven distribution of dispersed particles over the volume of the fluidized bed, the same as in the solutions described above.

Installation for producing silicon carbide (6), including a cylindrical vessel with a sealed casing, a gas distribution cone grate with vertical holes between the cone part of the grate and its horizontal plane bordering the gas distribution chamber, as well as an unloading hole and a locking pusher placed therein, made with the possibility of blocking the discharge opening. One electrode located along the axis of the vessel is passed through its cover, and the other electrode is made in the form of a cylindrical lining of the vessel.

This device, in addition to the disadvantages indicated previously for the method (6), has another significant drawback. The length of the vertical holes between the conical part of the grate and its horizontal plane bordering the gas distribution chamber is different. Closer to the axis of the vessel, the length of the holes decreases, due to which the gas flow in the central zone is more intense than at the periphery. This unevenness of the gas flow is further enhanced by the increased concentration of power released near the electrode, which increases the gas flow near the axis of the vessel. As a result, the instability of the fluidization regime increases. In addition, this solution (as well as other devices with a gas distribution grid) does not provide operational reliability, since when supplying gas from the bottom up through the gas distribution grid, the gas supply cannot be turned off to prevent dispersed material from entering the openings of the lattice and into the sublattice space.

A device for burning combustible waste in a vessel with a fluidized bed, in which the gas distribution system is located in the lower part and is made in the form of gaps between the plates, inclined from the periphery to the center. The location of the plates provides air supply under pressure in the direction from the periphery to the center and down the vessel (8).

The disadvantage of this device, as well as the previous one, is that the gas flow is directed from the periphery to the center, which, as indicated above, reduces the stability of the fluidization regime and leads to uneven density of the fluidized bed.

A known system for the distribution of gas supplied to a fluidized bed vessel, made in the form of a pyramidal lattice structure, tapering from the periphery to the center, formed by stepped plate rows separated from each other by spacers with the formation of gas-conducting channels connected with the sublattice space, also divided by annular partitions on separate channels for tiered sectioning of the gas mixture inlet along the height of the inlet conical part of the vessel. There is also a solution in which the channels supplying gas are formed by the gaps between the cones inserted into each other. The angle at the top of the cones is equal to the angle of repose (internal friction) of the processed material (9).

This solution does not eliminate the drawback of the previous one, associated with the direction of the gas flow from the periphery to the cent. Partially, this drawback can be compensated by the fact that, in the slots located closer to the periphery, a more intense flow can be directed than in the slots that are closer to the axis of the vessel.

A disadvantage of the device is that when the angle of the cone is equal to the angle of repose (internal friction) of the processed material, the processed material will remain on the cone when it is unloaded.

In addition, for high-temperature processes, the practical applicability of this device is problematic due to the complexity of manufacturing a gas distribution system. Conical refractory shaped products included in the gas distribution system are difficult to manufacture. In addition, the openwork design of refractory products does not meet the requirements of operational reliability.

Closest to the claimed device is a gas distribution grill for apparatuses with a fluidized bed, in which a set of adjacent plates adjacent to each other, having the form of sectors installed at an angle of 15-23 ° to the horizontal. Grooves are made in the plates at an angle of 25-30 °, which form channels for gas exit with the surface of the underlying plates, the channels narrowing along the gas [10].

In this solution, the disadvantage of the previous one, related to the direction of the gas flow from the periphery to the center, is reduced, but not eliminated due to the fact that the grooves in the plates forming the gas outlet channels are made at an angle of 25-30 °. This solution also contributes to some improvement in mixing by twisting the fluidized bed about a vertical axis. However, there remain disadvantages associated with the predominant direction of gas flow from the periphery of the vessel to its axis. The stationary regime of gas supply contributes to the formation of stable flows in the vessel, which increases the instability of the fluidization of dispersed particles.

In the known methods and devices, due to the uneven distribution of the dispersed material in the horizontal sections of the working volume of the vessel arising from their implementation, local overheating and power overruns occur. Deviations from the optimal fluidization regime reduce the yield and overall efficiency of the process. To maintain the fluidization regime, a significant margin in the performance of the gas supply system is required, which increases the cost of installation. Regulation of gas flow, as the only channel for controlling the fluidization regime, is not effective enough, since gas flow affects the energy balance and temperature of the process and, therefore, can vary within narrow limits determined by the need to maintain the required temperature of the layer.

The objective of the proposed technical solution is to increase the technological and energy efficiency of processing dispersed materials in an electrothermal fluidized (boiling) bed, namely, increasing the yield and reducing energy consumption. The technical result that can be obtained by implementing the proposed method and device also consists in increasing the uniformity of the distribution of the dispersed material and the ratio of its components, as well as the released electric power in horizontal sections of the electrothermal fluidized bed by intensifying its mixing by enhancing turbulence in the fluidized bed.

The problem is solved by creating a method (options) for the electrothermal processing of dispersed material in a fluidized bed and devices (options) for its implementation.

The single general inventive concept of the proposed solution is to force the fluidized bed directed at an angle to the gas motion vector, as well as to change the magnitude and / or direction of the specified force during processing of the dispersed material, which enhances the turbulence of the gas flow and intensifies the mixing of the fluidized bed. The technical problem can be formulated as a change in the functional composition of the process of boiling of dispersed material. When the liquid boils, gas bubbles form in it, their size increases as it rises to the surface and the liquid is intensively mixed. The objectives of the proposed solution are different. As in the known solutions, it is necessary, first of all, to ensure the mobility of the dispersed particles, that is, to achieve their fluidization in an upward gas flow. In contrast to the known solutions, the task is to suppress the process of formation and increase in the size of gas bubbles during the intensification of the mixing process by increasing the turbulence of the gas flow carrying dispersed particles.

The gas flow turbulization module, enhancing the fluidization of dispersed particles, has various technical options: in the form of a special design of a gas distribution and gas supply system and / or a system that creates a certain spatial distribution of electric current density. By their nature, the forces acting on the fluidized bed are either gas-dynamic in nature or electromagnetic (electrodynamic) in nature and perform the same function - turbulizing the movement of particles and gas in the fluidized bed. This reduces the effect of boiling the layer, that is, the effect of enlargement of gas bubbles and their opening on the surface of the layer, accompanied by the ejection and entrainment of particles by a gas stream. The effect of the formation of seals in the layer is also reduced. As a result, the concentration of particles is equalized in the layer.

In accordance with the nature of the forces that are used to enhance turbulence in the fluidized bed, two variants of the proposed method for processing dispersed material are determined. In one embodiment, increased turbulence of the fluidized bed is achieved due to the collision of the gas flows supplied to the fluidized bed. In the second variant of the method, electromagnetic forces are used to force the fluidized bed.

To ensure effective mixing of the fluidized bed in the first embodiment of the device with the gas flow supplied by the gas distribution system, the flow of gas supplied through the channel in the electrode, immersed from above in the fluidized bed, is encountered. According to the second embodiment, the design of the device provides a collision of flows due to the intersection of the axes of the channels along which gas is supplied to the fluidized bed. In the third embodiment of the device for force acting on the flow at an angle to the vector of its movement, a redistribution of the current density in the space between the electrodes is provided. Changing the current density in the sections of the split electrode by regulating the current of the sections leads to a change in the field of electromagnetic forces acting in the fluidized bed, and also intensifies its mixing. In accordance with the fourth variants of the device, the electromagnetic force on the flow at an angle to the direction of its movement is due to the interaction of the intrinsic magnetic field of the working current flowing between the electrodes through the fluidized bed and the external magnetic field, which is created by a solenoid covering the vessel in the area of the electrodes.

The force disturbing effect on the flow of the medium deflects the flow of gas and suspended particles from the direction that they would have had without disturbing force. The deviation of the gas flow and the collision of the flows leads to increased turbulence, as a result of which the jets of gas and compacted accumulations of dispersed particles formed in the fluidized bed are destroyed - the required technical result is achieved: the uniform distribution of particles in the fluidized bed is increased. The boundary layer on the surface of the lining of the vessel also decreases. In addition, gas bubbles formed in the fluidized bed and compacted clusters of dispersed particles are crushed. Particle entrainment associated with the opening of large gas bubbles on the surface of the fluidized bed is reduced. Breakthroughs of gas jets and the formation of large blocks of compacted particles are excluded. The stability and efficiency of the fluidized bed increases: the amount of unreacted component decreases, the yield is increased, and the energy consumption is reduced.

The use of additional channels for controlling the fluidization regime: the horizontal components of the vector field of the gas flow velocities, as well as the electromagnetic interaction determined by the spatial distribution of current density, makes it possible to optimize the parameters determining the energy and technological efficiency of the process. These parameters include total gas flow, operating current and operating voltage.

The essential features characterizing the invention.

The first variant of the method of electrothermal processing of dispersed material in a fluidized bed is that gas is supplied through a layer of dispersed material, in the upward flow of which the fluidized bed is provided and electric current is passed through it. During processing, the dispersed material is additionally mixed in the fluidized bed by dividing the feed gas stream into at least two jets, which are directed at an angle to each other.

A variation of the first variant of the method is that in the zone located below the average level of the fluidized bed, at least one of the jets is directed vertically downward.

Another variation of the first variant of the method is that the processing process is conducted with a change in the flow rate of the jet directed vertically downward.

Another variation of the first variant of the method is that the jets are directed along intersecting paths oriented along the tangents to the surface covering the fluidized bed, or at an acute angle to the said tangents.

A variation of the first variant of the method also consists in the fact that the jets of the supplied gas are directed along intersecting trajectories oriented along the tangents to the surface covering the fluidized bed, or at an acute angle to the said tangents, some jets being directed clockwise relative to the direction of the upward flow, and others - counterclock-wise.

A variation of the first variant of the method also consists in the fact that the jets of the supplied gas are directed along intersecting paths oriented along the tangents to the surface covering the fluidized bed, or at an acute angle to the said tangents, some jets are directed clockwise relative to the direction of the upward flow, while others are directed counterclockwise, moreover, the ratio of the flow rate of the jets supplied clockwise and counterclockwise during the processing is changed.

The second variant of the method of electrothermal processing of dispersed material in a fluidized bed is that gas is supplied through a layer of dispersed material, in the upward flow of which the fluidized bed is provided, and an electric current is passed. During processing, the dispersed material is additionally mixed in the fluidized bed by changing the spatial distribution of the electric current density.

A variation of the second variant of the method is that during processing, the electric current density is redistributed between different sections of the fluidized bed with a frequency of from 0.01 to 1000 Hz.

Another variation of the second variant of the method also consists in the fact that during processing, the electric current passed through the fluidized bed is rectified and modulated with a frequency from 0.01 to 1000 Hz.

Another variation of the second variant of the method is that the electric current passed through the fluidized bed is rectified and modulated at a frequency of from 0.01 to 1000 Hz, and the modulation depth is changed during processing.

Another variation of the second variant of the method also lies in the fact that the processing process is carried out by reversing an electric current passing through a fluidized bed with a frequency of from 0.01 to 1000 Hz.

Another variation of the second variant of the method is also that the processing process is carried out by changing the frequency of the current reverse in the range from 0.01 to 1000 Hz.

Another variation of the second variant of the method is also that the processing process is carried out by changing the duty cycle of pulses of positive and negative current polarity.

A variation of the second variant of the method also lies in the fact that during processing, a rectified current is additionally passed along a circuit covering the fluidized bed.

A variation of the second variant of the method lies in the fact that during processing, the rectified current passed through the circuit covering the fluidized bed is modulated with a frequency of from 0.01 to 1000 Hz.

A variation of the second variant of the method also lies in the fact that the rectified current passed through the circuit covering the fluidized bed is modulated with a frequency from 0.01 to 1000 Hz, and the depth or frequency of the modulation is changed during processing.

A variation of the second variant of the method also lies in the fact that, additionally, a current is passed through the circuit covering the fluidized bed, which is reversed at a frequency of from 0.01 to 1000 Hz.

A variation of the second variant of the method also lies in the fact that during processing, the frequency of reverse current passing through the circuit covering the fluidized bed is changed in the range from 0.01 to 1000 Hz.

A variation of the second variant of the method also consists in the fact that during processing, a polarity of the current passing through the circuit covering the fluidized bed is reversed with a frequency from 0.01 to 1000 Hz, changing the duty cycle of pulses of positive and negative polarity.

The first variant of the device for implementing the first variant of the method comprises a lined vessel with a system for distributing and supplying a gas stream to a vessel for fluidizing the dispersed material in an upward gas flow, electrodes of at least one of which is installed vertically in the vessel and immersed in the fluidized bed. The gas flow distribution and supply system is made in the form of branches, and the at least one electrode is made with an axial channel to which at least one of the branches of the gas flow distribution system is connected.

When executing the first embodiment of the device, a modulation unit for the ratio of the flow rate of the gas stream supplied to the vessel through different branches was introduced into a branch brought to the electrode with an axial channel.

The second variant of the device for implementing the first variant of the method comprises a lined vessel, a gas distribution and supply system for fluidizing the dispersed material in an upward gas stream. The lining of the vessel in the lower part is made in the form of a bowl, in which there are channels connected to the gas distribution and supply system, whose axes intersect in a vertical projection.

In the execution of the second embodiment of the device, the vessel bowl is made of horizontal plates mounted with gaps forming channels for supplying gas.

In another embodiment of the second embodiment of the device, the vessel bowl is made of plates arranged pyramidally with the plates inclined to the axis of the vessel at an angle of five degrees to an angle fifteen degrees greater than the angle of repose of the dispersed material.

In another embodiment of the second embodiment of the device, the channels are located parallel or at an acute angle relative to the faces or tangent to the inner surface of the bowl.

In another embodiment of the second embodiment of the device, the channels are made at different levels with alternating clockwise and counterclockwise directions relative to the axis of the vessel.

In another embodiment of the second embodiment of the device, the channels are located tangent to the inner surface of the bowl, made at different levels with alternating clockwise and counterclockwise directions relative to the axis of the vessel. The channels of each direction are combined, in their own group, with a gas supply separate from the other group, and a modulation unit for the ratio of the gas flow rate through the channel groups is introduced into the gas flow distribution system.

The third variant of the device for implementing the second variant of the method comprises a lined vessel, a gas distribution and supply system, electrodes connected to the terminals of the power source. One of the electrodes is made of sections isolated from each other, the power source is made with an output split into sections according to the number of electrode sections and a current control system in sections, and each of the electrode sections is separately connected to the corresponding output section of the power source.

The fourth variant of the device for implementing the second variant of the method comprises a lined vessel, a gas distribution and supply system, electrodes connected to a direct current power source. The device is equipped with an additional power source and a solenoid connected to an additional power source, covering the electrode location area.

In another embodiment of the fourth embodiment of the device, an additional power source is configured to modulate the rectified current with a frequency of from 0.01 to 1000 Hz and / or reverse the current with a frequency of from 0.01 to 1000 Hz.

In FIG. 1 schematically shows a device for the electrothermal processing of dispersed material in a fluidized bed.

In FIG. 2 shows a horizontal section of a lined vessel with a tangential flow of gas jets into the fluidized bed in a clockwise direction.

In FIG. 3 shows a horizontal section of a lined vessel with a tangential flow of gas jets into the fluidized bed counterclockwise.

In FIG. 4 shows a vertical section through a vessel for electrothermal processing of dispersed material in a fluidized bed surrounded by a solenoid.

In FIG. 5 shows a horizontal section in which the network of channels of the gas distribution system is made in plates inclined to the axis of the vessel.

In FIG. 6 shows a vertical section in which the network of channels of the gas distribution system is made in plates inclined to the axis of the vessel. .

According to the first variant of the method, gas 2 is supplied through the bed of dispersed material 1 (Fig. 1). In the upward gas stream 3, 4, fluidization of the bed 1 is provided and electric current 5, 6 is passed through the fluidized bed 1. The difference from the known methods is that during the processing, the dispersed material is additionally mixed in the fluidized bed 1 by dividing the feed gas stream 2 into at least two jets that are directed at an angle to each other.

For example, stream 2 is first divided into two parts 7 and 8, each of which is further divided into two jets 3 and two jets 4, as well as four jets 9, respectively. Jets 3 and 4, in this case, are directed at an angle of 180 ° to the jets 9, which ensures their collision in the fluidized bed. As a result of the collision, the paths of the jets change into vertically directed ones, which ensures fluidization of the dispersed particles, and the flow acquires a turbulent character. The turbulization of the gas flow carrying dispersed particles provides mixing of the fluidized bed and prevents the formation of large gas bubbles in it.

This option can be implemented by feeding jets of various gases at an angle to the other and mixing them inside the vessel. In the case of the supply of gases between which an exothermic reaction is possible, this solution eliminates the so-called slip, which increases the safety of the process. The increase in efficiency is ensured by good mixing of the colliding jets of gases.

In the implementation of the proposed first variant of the method, as a result of the collision of jets directed at different angles to each other, turbulences are formed and the gas flow is directed upward. An upward flow of gas is formed, which causes fluidization of the dispersed material. The increased turbulence of the flow due to the collision of the jets provides a more uniform distribution of dispersed particles in the volume of the fluidized bed 1.

According to a variation of this method, at least one of the jets 10 in FIG. 1 is directed vertically downward, preferably in an area located below the average level 11 of the fluidized bed 1. This jet 10 is directed at right angles to the directions of gas jets 3 , 4, 9. The jet 10 spreads along the lower boundary of the fluidized bed and collides with the jets 3, 4 and 9. This effect is enhanced if the distance from the zone into which the jet 10 is introduced to the upper level of the fluidized bed exceeds the distance to its lower level. In this case, the turbulence of the flow is also enhanced and the homogenization of the fluidized bed is ensured.

In development of this method, to further improve mixing, the processing process is carried out with a change in the flow rate of the jet 10 directed vertically downward. For example, the gas consumption of one of the jets is reduced by half. The time interval during which a new flow structure is formed in the fluidized bed is measured. Next, set the period of change of gas flow in this jet equal to half the measured time interval, and the depth of change in the flow rate equal to, for example, half of the initial gas flow of the downstream jet 10. The total gas flow can be kept constant by changing the flow of other gas jets 3, 4, 9 in antiphase with a change in the gas flow rate in the jet 10. A change in the flow ratio of the colliding jets 3, 4, 9 with the jet 10 prevents the formation of stable flows or vortices, which could lead to a stable distribution Jelenia density, that is, to the heterogeneity of the fluidized bed. The change in the effect of the interaction of counter-directed gas flows is also carried out by moving the electrode vertically. When the electrode rises above the average level 11, the deceleration of the jet 10 by the upward gas flow is more pronounced and the flow rate ratio of the colliding gas jets changes due to a change in the flow rate of the part of the jet 10 reaching the lower boundary of the fluidized bed.

In another variation of the first of the proposed methods, the feed gas jets are directed along intersecting paths oriented along tangents to the surface covering the fluidized bed, or at an acute angle to the tangents mentioned. For example, jet 12 in FIG. 2 is fed along a path whose axis 13 is parallel to the tangent to the surface 14 spanning the fluidized bed 1. A jet 15 is fed along a path whose axis 16 is tangent to the surface 14 spanning the fluidized bed 1. In the solution shown in FIG. 2, the boundary 17 of the jet 12 external to the fluidized bed 1 coincides with the tangent drawn in the horizontal plane to the circle 18 formed by the section of the surface of the fluidized bed by this plane. The axes of the paths 13 and 16 of the jets 12 and 15 intersect (at point 19), and therefore the jets deviate from their original paths and collide. Similarly, the formation and collision of other jets - shown in FIG. 2.

One embodiment of this method is illustrated in FIG. 3, according to which the jet 20 is fed along a path whose axis 21 is at an acute angle 22 to the tangent 23 to the circle 24, which is a horizontal section of the surface that covers the fluidized bed 1. The tangent is drawn at the intersection of the axis 23 of the path with the above circle . In other words, the jets are fed tangentially with respect to the fluidized bed. The outer boundary 25 of the jet 20, in this case, is directed at an angle different from 180 ° to the surface of the fluidized bed, which provides deeper penetration of the jet from the surface to the axis of the fluidized bed. The axes 21 and 26 of the jets 20 and 27 intersect at point 28, in connection with which the jets 20 and 27 deviate from their original trajectories and the collision of the gas jets. The value of angle 22 is selected from the condition of ensuring uniformity of gas flow over the cross section of the fluidized bed, trajectories 25 and 26

As a result, a rotational movement of the fluidized bed around the vertical axis is created, which enhances the turbulence in the fluidized bed and provides an additional effect of mixing it.

In the development of this method, some jets are directed clockwise relative to the direction of the upward flow (as shown in Fig. 2), and other jets are counterclockwise (as shown in Fig. 3). A special case of the proposed method is the direction of the supplied gas along trajectories that are located at an acute angle relative to the tangents to the surface of the fluidized bed, as described above. In this case, the sections of the fluidized bed, located closer to its axis, are more involved in circular motion, which to some extent compensates for the centrifugal forces arising from the circular motion of particles in the outer region of the fluidized bed.

To enhance turbulence in the entire volume of the fluidized bed at different heights, not only change the direction clockwise and counterclockwise, but also change the angle of entry of the gas jets. For example, in section AA (FIG. 2), the jets are fed clockwise tangentially to surface 14, and in section BB (FIG. 3), jets are fed counterclockwise at an angle of 22 relative to tangent 23 to the layer surface. Since sections A-A and B-B of surface 14 and 24 have different radii 29 and 30 (in Fig. 1, sections A-A and B-B are shown, shown in Fig. 2 and Fig. 3), various sections of the cross section of the fluidized bed.

To prevent the formation of regular vortices during processing, the ratio of the flow rate of the jets supplied clockwise 12, 15 (Fig. 2) and counterclockwise 20, 27 (Fig. 3) is changed. The depth of change in the ratio of the flow rate of the jets fed with different directions of swirl vary in a wide range, which does not reach 100%. For example, set the flow rate of gas jets clockwise equal to 95% of the total gas flow, and 5% through jets directed counterclockwise. Then, the gas flow ratio is changed to the opposite: the flow rate of gas jets directed counterclockwise is set equal to 95% of the total gas flow rate, and 5% through the jets clockwise. Next, the variation in gas flow in the jets is repeated. The gas flow rate in any jets is not reduced to zero, in order to avoid reverse purging of dispersed particles.

In the second variant of the method of electrothermal processing of dispersed material in a fluidized bed 1 (Fig. 1), gas 2 is supplied through a layer of dispersed material, upstream 3, 4, 9 of which provide fluidization of the bed, and an electric current is passed, for example, 5, 6. In contrast from known methods in the processing process, the dispersed material is additionally mixed in the fluidized bed 1 by changing the spatial distribution of the electric current density. The change in the spatial distribution of the current density can be performed in the fluidized bed itself, or provided by the formation of additional current outside the fluidized bed. For example, increase the current 5 (and, accordingly, the current density) and decrease the current 6. Accordingly, the electrodynamic forces 31 are strengthened and the forces 32 are weakened, by analogy with the pinch effect. A change in the ratio of electromagnetic forces 31 and 32 acting on the fluidized bed 1 at an angle to the upward gas flow 3, 4, causes a change in the direction of motion of the fluidized bed, which provides additional mixing and equalization of the concentration of dispersed particles.

The second variant of the proposed method operates as follows. When a gas stream is passed through a dispersed material, due to the random nature of the process of interaction of an upward gas stream with particles, local accumulations of dispersed particles are formed, and in the neighboring regions, respectively, the volume concentration of particles decreases. The upward gas flow is amplified in an area with a lower concentration of particles, since the hydraulic resistance of these zones is less than that of local clusters of particles. The heterogeneity that has arisen by chance tends to increase, since particles from zones with a more intense gas flow are carried to the surface of the layer, and a downward movement is formed in the compaction zone. The destruction of such structural inhomogeneities is carried out by changing the spatial distribution of the electric current density. For example, as shown in FIG. 1, increase the current density 5 in one zone and decrease the current density 6 in another zone. The electrodynamic forces 31 in the zone with current 5 become greater than the forces 32 acting in the zone with current 6, as a result of which a change in the balance of forces exerts a dynamic effect on the zones, which contributes to the destruction of structural inhomogeneities in the layer.

The gas flow rate increases sharply in the zones of the fluidized bed in which chemical reactions take place, in which gaseous products are formed. The temperature of the zones and the rate of chemical reactions are determined by the density of the electric current. Therefore, the redistribution of the density of electric current, its modulation, reverse polarity of the current lead to a corresponding change in gas flow. Fluctuations in the gas flow in different zones prevent the formation of large gas bubbles and seals in the fluidized bed, which improves the uniformity of the fluidization of the dispersed material. The advantage of this solution over the well-known analogue (7), in which a sound vibration source is installed under the gas distribution grill, as well as over other solutions in which acoustic vibrations of the gas flow are formed outside the working space of the vessel, lies in higher dynamic characteristics of the mechanism of formation of effects directly inside the fluidized layer. The frequency range in the proposed solution is wider, since the acoustic effects are formed directly in the working space of the vessel 1 and there is no acoustic filter in the form of a gas distribution system between the source of acoustic vibrations and the working space of the vessel 1. In addition, the level of mechanical vibrations of structural elements is reduced, which increases the reliability of their work.

A variation of the second embodiment is a method in which the electric current density 5 and 6 in FIG. 1 redistribute between different sections of the fluidized bed with a frequency of from 0.01 to 1000 Hz. A larger value of the current density, in this case, is on the site indicated by the longer arrows 5, and a lower value by the short arrows 6. The indicated frequency range here and below is determined by the nature of the inertial processes occurring in the electrothermal fluidized bed. The lower boundary of the frequency range is associated with the mobility of the dispersed particles and is determined by the time interval over which the particles are displaced by a distance commensurate with the size of the fluidized bed under the influence of the above imbalance of electrodynamic forces. The upper boundary of the frequency range of the frequency is associated with the mobility of gas ions generated in the electrothermal fluidized bed, and is determined by the time interval during which the ions are displaced by a distance commensurate with the size of the fluidized bed under the influence of the above imbalance of electrodynamic forces. This takes into account the current flowing through the dispersed particles, as well as the current flowing through the partially ionized gas generated in the electrothermal fluidized bed.

Varieties of the second option are also methods in which the current passed through the fluidized bed is rectified and / or modulated with a frequency of from 0.01 to 1000 Hz, and the modulation depth is kept constant during the processing or is changed. Modulation is carried out by superimposing the variable component on the rectified current, and the amplitude of the variable component, in this case, does not exceed half of the rectified current (otherwise the current would become reversible). Modulation of the current and a change in its depth increase the efficiency of mixing the fluidized bed by introducing irregularities in the force electrodynamic effect on the layer and enhances turbulence in the layer.

Varieties of the second option are also methods in which reverse the current passed through the fluidized bed, with a frequency of from 0.01 to 1000 Hz. Additional effects on the layer during processing are due to a change in the frequency of reverse current or its duty cycle (that is, the ratio of the duration) of pulses of positive and negative polarity. Here we use a method of introducing irregularities in the force electrodynamic effect on the layer, taking into account the differences in the nature of power release in the region of cathode and anode spots formed when electrical discharges occur between dispersed particles in an electrothermal fluidized bed. The anode and cathode spots have different mobility and are characterized by different current densities, and therefore, current reversal causes a volume redistribution of power and a change in the nature of the force displacement of ionized gas flows and an increase in turbulence in the layer. The frequency range is also determined by the inertial characteristics of dispersed particles and plasma in an electrothermal fluidized bed.

For example, they begin the process with a reverse frequency of 0.01 Hz, given that initially, at a low temperature in the fluidized bed, conductivity predominates due to dynamically aligned chains of electrically conductive dispersed particles directly in contact. The low value of the current reversal frequency allows, thanks to fluctuations in the magnitude and spatial distribution of electric power during current reversal, to exert an oscillatory hydraulic effect on the bed, which improves the fluidization mode. After heating the fluidized bed and increasing the volume of gases formed as a result of chemical reactions, the distance between the dispersed particles increases and the conductivity acquires a spark character. Since the mobility of ionized particles, which determine the conductivity in the discharge gaps, significantly exceeds the mobility of dispersed particles, an effective effect on the fluidized bed is provided at a higher frequency of current reversal, for example, 200 Hz.

Additionally, in the layer heated to the operating temperature, the duty cycle of pulses of positive and negative current polarity is changed, which introduces irregularity. The electrodynamic effect on the fluidized bed.

In addition, the second variant of the method is performed by changing the spatial distribution of the electric current density so that a rectified or reverse current 33 in FIG. 4 along the contour surrounding the fluidized bed 1 shown in FIG. 4 in the form of a solenoid 34. The current 33 passed through the solenoid 34 creates a magnetic field, the lines of force 35 of which are coplanar with the lines of current density 5, 6 and are located with respect to the lines of current density at angles 36. Interaction of the magnetic field created by current 33 of solenoid 34, s the current 5, 6 flowing from the bed 1, creates volume forces that cause the circular motion 37 of the fluidized bed 1. The vector field of the velocities of the particles and gas in the bed changes. The circular motion intensifies the mixing of the material in the layer and increases the uniformity of the distribution density of dispersed particles in it and the averaging of the chemical and dispersion composition in the layer (equalization of the ratio of various components). The efficiency of leveling the composition of the layer is increased by modulating the current in the solenoid with a frequency of from 0.01 to 1000 Hz. To obtain an additional mixing effect, the frequency of the current 33 in the solenoid 34 is changed in the specified range and / or the depth of modulation of the current is changed. An additional effect of mixing is also obtained by changing the polarity of the current 33 in the solenoid 34, which leads to a change in the opposite direction of the circular motion 37 of layer 1. The choice of the frequency range of the current of the solenoid, as before (current in the layer), determines the efficiency of mixing of the layer, which further increases by changing the frequency and / or duty cycle of the pulses of positive and negative polarity of the current 33 in the solenoid 34. Changing the duty cycle of the pulses leads to a change in the intensity and average direction circular motion 37 of the fluidized bed 1, which allows to achieve a desired degree of averaging composition layer 1. The above-described effect on the vector gas and particle velocity has a pulsating character, thereby unsteady flow in the fluidized bed and its homogenization.

To implement the above-mentioned control of the parameters of the electric mode, a controlled rectifier or inverter is used, made according to known schemes, for example, a thyristor bridge rectifier and an inverter with a DC link, respectively.

The device (option 1) for implementing the first variant of the method comprises a sealed vessel 38 in FIG. 1, made for example of steel, with a lining 39 of refractory material. It also contains a distribution system 40, 41, 42 of gas flow 2 and its supply 52, 53, 54 to the vessel 38 for fluidization of the dispersed material 1 in the upward gas flow 3, 4. There are also electrodes, at least one of which 43 is installed in the vessel 38 is vertically and immersed in the fluidized bed 1. In contrast to the known solutions, the gas flow distribution and supply system is made in the form of branches, and said electrode 43 is made with an axial channel 44 to which one of the branches 45 of the gas flow distribution system 2 is connected. If in a vessel but several vertical electrodes immersed in the fluidized bed with axial channels, a branch of the gas distribution and supply system is connected to each of them.

In FIG. 1 shows an example implementation of the claimed device. The vessel 45, made in the form of a steel sealed casing with a lid, lining 39, electrodes 43, 52, channels 54 of the gas distribution and supply system, are symmetrical about the vertical axis. The shape of the vessel and the lining in horizontal section can be round or multifaceted. By the number of electrodes passed through the lid of the vessel and immersed in the fluidized bed, the device can be single-electrode, two-electrode or multi-electrode. When using more than one electrode, passed through the cover, they can be under the common potential or under different potentials. In the latter case, the current also closes between the electrodes passed through the lid of the vessel. The axial hole in the electrode is made with a diameter from 0.05 to 0.3 of the diameter of the electrode. The minimum diameter of the axial hole in the electrode corresponds to the lowest flow rate of gas supplied through the hole in the electrode, which affects the nature of the flow of the rest supplied to the gas vessel. The maximum diameter of the axial hole in the electrode is limited by the condition of the mechanical strength of the electrode. The sealed vessel 38 with the lining 39, in addition to the above elements, has: a loading unit 46 of the source dispersed material 47, a unit 48 for removing gases from the vessel, a unit 49, 50 for discharging the dispersed material 1.

The device operates as follows. In the lined vessel 38, 39 through the boot node 46 serves the source of the dispersed material having a conductivity sufficient to provide a given electrical mode. For example, a mixture of powders of a carbon reducing agent and silica sand is supplied. From above, a hollow electrode, for example a graphite electrode, is lowered through a sealed opening in the lid of the vessel using an electrode transfer and bypass system like in ore-thermal electric furnaces. The electrode is made with an axial hole, for example, with a diameter equal to 0.1 of the diameter of the electrode. Gas is supplied from below through the dispersed material, distributing its upward flow 3, 4, 9 in a horizontal section of the vessel using system 8, distributing and supplying a gas stream. The gas flow rate is set above a critical value such that fluidization of the dispersed material 1 occurs. The hollow electrode is positioned so that its working end is below the middle 11 of the fluidized bed 1 and, using the gas distribution system 8, turn on the gas supply through the channel 44 to the hollow electrode 43. Since the hydrodynamic resistance of the layer located above the working end of the electrode exceeds the resistance of the underlying layer, the downward flow of gas 10 under the action of the dynamic pressure of the gas jet exiting sediment 44 in the electrode 43, spreads along the bottom of the vessel and crosses the upward flow 3, 4, 9. As a result of the interaction of intersecting flows increases turbulence, which improves mixing in the fluidized bed. Next, an electric current is passed through the fluidized material and heat treatment is carried out. The recycled particulate material 1 is removed from the vessel 38 through the discharge unit of the particulate material by lifting the plug 49 with a pusher 50.

To further increase turbulence in the first embodiment of the device, the branch 45, connected to the electrode 43 with the axial channel 44 of the gas distribution and supply system, is equipped with a unit 51 for modulating the ratio of the flow rate of the gas stream supplied to the vessel through different branches 7, 8 and 45. Modulation of the ratio of flow rates 3, 4, 9, intersecting with the stream 10 allows you to eliminate the stability of the formation of gas bubbles and sealed blocks in the fluidized bed, which increases its uniformity.

The second embodiment of the device for implementing the first embodiment of the method comprises a vessel 38 in FIG. 1 with a lining 39, a system 40 for distributing and supplying a gas stream 2 for fluidizing the dispersed material 1 in an upward gas stream 3, 4, 9. In contrast to the known solutions, the lining 39 of the vessel 38 in the lower part is made in the form of a bowl 52, 53, in which channels 54 are provided. The channels supply gas to the fluidized bed. The execution in the form of a bowl of the lower part of the lining, that is, an open tank at the top, creates conditions for the required distributed distribution of channels in the lower part of the lining, as well as for the organization of an upward flow of gas, providing fluidization of dispersed particles. The gas distribution of the flow is carried out by parts 40, 41, 42 of the gas flow distribution and supply system 2 connected to the channels. The conical-shaped bowl consists of plates 52 in FIG. 2 made in the form of sectors. Channels 54 (in FIG. 1) are formed by gaps between adjacent plates. In FIG. 2, the axes 13 and 16 of the channels (coinciding with the axes of the paths of the jets 12, 15) intersect at point 19. The lower part of the lining 39 in FIG. 1, having the shape of a bowl, can be made, for example, in the form of a truncated cone or a truncated pyramid, in the downward-facing smaller base of which an unloading unit 49 is made. FIG. 2 shows a horizontal cross-section of a truncated cone at the bottom of the lining 39. The channels are formed by gaps between the plates located in layers in the form of rings or polygons. The layers of the plates form a conical or pyramidal structure, in which the distance to the axis of the vessel decreases from the upper layers to the lower adjacent to the node 49 of the discharge of dispersed material located on the axis of the vessel.

The device operates as follows. The loading, fluidization and heat treatment of the dispersed material, as well as its unloading, are performed similarly to the above. Due to the fact that the axes 13 and 16 of the channels in FIG. 2 intersect, the jets 12 and 15 supplied into the vessel lining collide, as a result of which the turbulence in the fluidized bed increases and its uniformity increases. The general rotational motion of the gas stream also contributes to this, as a result of which the motion in the fluidized bed becomes turbulent.

In the execution of the second variant of the device, the vessel bowl is made of horizontal plates 52, 53 installed with gaps 54 (in Fig. 1, symmetrically located plates and gaps are shown), forming channels that serve to supply gas jets 3, 4, 9. into the layer there should be gaps between adjacent plates in the same layers as the plates (similar to Fig. 2). Channels may also be provided between the plate layers, as in FIG. 1. In FIG. 2 shows another possible embodiment of one of the layers of plates 52 arranged to form a horizontal ring. In both versions, the inner radii of the rings located as in FIG. 1, one above the other in height of the bowl, decreases from the inner radius 55 of the lining 39 to the smallest radius 57 of the lower ring. The radii of the rings, in decreasing order, are 29, 30, 56, 57. The inner surfaces of the rings are made conical, so that when unloaded, all dispersed material is removed from the vessel. The use of gaps between the plates for the formation of gas distribution channels simplifies the manufacture of the device. It is also possible execution in which the channels are made inside the plates or on their surfaces adjacent to adjacent plates.

In another embodiment of the second embodiment of the device, as shown in FIG. 5 and FIG. 6, the vessel lining bowl is made of plates 58 arranged by pyramidal layers 59, 60, 61 with the plates 58 inclined to the horizon at an angle of 62, which is from five degrees to an angle fifteen degrees greater than the angle of repose of the dispersed material. Under the dispersed material here we should understand both the source material and the dispersed product resulting from processing. The specified inclination of the plates (if necessary, and the gap between them) is ensured by installing them on the supporting elements 63, in which openings 64 are made for equalizing the gas pressure 2 in the space 65 under the plates 58. The minimum angle of inclination of the plates ensures their spacing, and the maximum (by fifteen degrees exceeding the angle of repose of the dispersed material) - complete cleaning of the working space from the dispersed material when it is unloaded, which allows to increase the yield of the dispersed material suitable for thermal processing. The pyramidal bowl consists of plates 58 in FIG. 5 and 6, made in the form of trapezoids. In the plates 58, grooves 66 are made, which, together with the surface of adjacent plates, form channels 66.

A more efficient mixing in the fluidized bed is achieved with the further development of the proposed device. FIG. 5 and FIG. 6 explain this device, made with a faceted bowl, in which the plates are laid in the form of a truncated pyramid, located with a large base up. In the plates 58, located at an angle of 62 to the horizontal, channels are made in the form of grooves 66 with external (relative to the working volume with a fluidized bed) faces 67 and an axis 68 located parallel to the inner surface 69 of the adjacent plate of the bowl. In the plates, the channel axes form an acute angle with respect to the internal (facing the vessel axis) faces of the plates themselves. In the embodiment shown in FIG. 5 and FIG. 6, the plates 59, 60, 61 forming the bowl are ledges, which simplifies the design of the device.

When the bowl is executed in the form of a truncated cone located with a large base up, the axes of the channels forming the jets are parallel to the tangents to the circles formed by horizontal sections of the inner surface of the bowl or at an acute angle to the indicated tangents. The layers of the bowl, in this case, are made in the form of conical funnels inserted into each other.

With the further development of the proposed device, the channels, namely their axis, are made at different levels of the bowl with alternating directions relative to the axis of the vessel clockwise and counterclockwise. For example, channels made at section AA in FIG. 2 are directed clockwise relative to the axis of the vessel. The channels made at the level of section BB in FIG. 3 are directed in the opposite direction, in this case, counterclockwise. This device design provides multidirectional swirling of the bed at various levels, additionally enhances the turbulence of the flow and creates a highly efficient mixing of the fluidized bed.

An additional development of the design of the second variant of the device is that the channels, as in the previous case, are located tangentially with respect to the inner surface of the lining of the vessel, and their directions alternate clockwise and counterclockwise relative to the axis of the vessel at different levels. In addition, the channels of each of the directions are combined into their own group. The channels located in section AA in FIG. 1, are combined into a separate group with a common sublattice collector 41 with a gas flow 7 supplied to it. The channels located in section BB in FIG. 1, are combined into another group by another sublattice collector 42 with a gas stream 8 supplied to it. The sublattice collectors 41 and 42 are separated by a partition 70. A modulation unit 71 of the gas flow rate ratio 7 and 8 through channel groups 41 and 42 is introduced into the gas flow distribution system 40 , which allows you to add additional non-stationary flow in the fluidized bed 1, thereby preventing the formation of stable zones with large deviations of the density of the layer from the average value.

This device additionally uses a dynamic turbulization mechanism that takes into account the inertial characteristics of the gas stream with fluidized particles. Modulation of the ratio of the components of the gas stream through groups of channels leads to the fact that the component of the gas stream that has increased expands its cross section due to a decrease in the cross section of the component of the gas stream, which has decreased. In other words, acceleration and deceleration of individual sections of the gas flow occur, which leads to increased turbulence.

The third embodiment of the device for implementing the second embodiment of the method comprises a vessel 38 in FIG. 1 with lining 39 for dispersed material 1. There is a system for distributing and supplying 40, 41, 42, 52 gas flows 2 for fluidization of the dispersed material. There are also electrodes 43, 52, 53 connected to the terminals of the power source 72. One of the electrodes (for example, in FIG. 1 — peripheral) is made of sections 52 and 53 isolated from each other (in FIG. 1 — four isolated sections of the peripheral electrode ) Corresponding layer elements, for example 52 and 53 in FIG. 1 are made of electrically conductive material. The electrode sections are electrically insulated from each other using other elements made of electrical insulating material. The electrically conductive elements are equipped with electrical leads connected to the terminals of the same name of the power source 72. The power source is made with the output, split into sections (in Fig. 1 - four) according to the number of sections of the electrode. There is a system 73 of current regulation 74, 75 in each of the sections. Each of the sections of the electrode 52, 53 is separately connected to the corresponding section of the power source 72. The polarity of the terminals of the sections of the power source is indicated by the signs “+”, and the general output of the power source by the signs “-”. Separate control of the current 74, 75 by the system 73 in each of the sections of the power supply 72 is implemented by comparing the feedback signals 76, which are generated by the current sensors 77, included in the circuit of each of the sections, with task 78, which is entered into the control system 73.

In the third embodiment of the device, unlike the previous ones, the equalization of the concentration of dispersed particles in the fluidized bed is achieved by the fact that by separately controlling the current in different sections of the electrode, a spatial redistribution of the electric current density 5, 6 in FIG. 1. Accordingly, a spatial redistribution of electrodynamic forces 31, 32 is ensured, which leads to additional mixing of the fluidized bed. If inhomogeneities occur in the fluidized bed, the current fluctuations 74 and 75 are controlled using devices 77. To reduce the inhomogeneities, the current value of the different sections of the power supply is dynamically redistributed with a frequency from 0.01 to 1000 Hz, or the source current is modulated, and the depth and / or modulation frequency in the specified frequency range. A variation of this technical solution is to change the polarity of the current with a frequency of from 0.01 to 1000 Hz. To modulate the rectified current, a controlled rectifier is used, and for reversing the polarity of the current, an inverter made according to known schemes is used. The indicated parameters of the electric mode are regulated, providing a decrease in the fluctuations of the electric mode from a given value 78.

The fourth embodiment of the device for implementing the second embodiment of the method, in addition to the lined vessel 38 in FIG. 4 for fluidization of the dispersed material 1, the gas flow distribution and supply system 2, the electrodes 43, 79 connected to the terminals of the power supply 72 is equipped with an additional power supply 80 and a solenoid 34, covering the area of the working areas of the electrodes 43, 79. The solenoid 34 is located outside the lining . The solenoid 34 is connected to an additional power source 80, made according to one of the known rectifier circuits.

A device made according to the fourth embodiment operates as follows. In the fluidized bed 1 in FIG. 4 between the electrodes 43 and 79, a current 5, 6 flows, which is supplied from the power source 72. The current 33 of the solenoid 34 creates a magnetic field, the lines of force 35 of which are coplanar to the lines of current density 5, 6 and are directed to them at angles 36. As a result of the interaction of the magnetic field of a solenoid with a current flowing between the electrodes, a spatial field of electrodynamic forces is formed having a tangential orientation, conventionally shown at 37. Under the action of electrodynamic forces, a circular motion of the fluidized bed occurs, ensuring ayuschee his agitation.

In development of the fourth embodiment of the device, an additional power supply 80 in FIG. 4 is configured to modulate rectified current 33 with a frequency of from 0.01 to 1000 Hz or reverse current 33 with a frequency of from 0.01 to 1000 Hz. As in the previous device, in this case, under the action of electrodynamic forces, a circular motion of the fluidized bed is created. These forces vary by modulating the current in the solenoid made using a controlled rectifier having, for example, a three-phase bridge thyristor circuit. When the current is reversed in the solenoid, the forces causing the circular motion of the layer change direction in the opposite direction. These effects impede the formation of stable flows, which makes it possible to further homogenize the fluidized bed and reduce the loss of dispersed particles caused by their entrainment from bubbles opening on the surface of the layer. To ensure reverse current, the power source 80 is, for example, according to the scheme of a bridge reversing rectifier or an inverter is used.

The advantages noted above of the proposed technical solutions allow to increase the technological and energy efficiency of processing dispersed materials in an electrothermal fluidized bed, namely, to increase the yield and reduce energy consumption. The achievement of these advantages is achieved by solving the technical problem in the proposed method and device, namely by increasing the uniformity of the distribution of the dispersed material and the ratio of its components in horizontal sections of the electrothermal fluidized bed by intensifying its mixing due to introduced turbulence. As a result of gasdynamic and / or electrodynamic effects on the flow of gas and dispersed particles, fractal waves are formed that intensify the equalization of the concentration of dispersed particles and the mixing of the reagents in the fluidized bed.

From a comparative analysis with the prior art, it can be concluded that the claimed technical solution meets the patentability conditions of “novelty” and “inventive step”. As follows from the description, the method of electrothermal processing of a dispersed material in a fluidized bed and a device for its implementation can be implemented by known actions and means from available materials and meet the patentability criterion of "industrial applicability".

Information sources

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Claims (30)

1. A method of electrothermal processing of a dispersed material in a fluidized bed, in which a gas is supplied through a layer of dispersed material, in the upward flow of which a fluidization of the bed is provided, and an electric current is passed through it, characterized in that during the processing, the dispersed material is additionally mixed in the fluidized bed by dividing the feed gas stream into at least two jets that are directed at an angle to each other. 2. The method according to p. 1, characterized in that in the zone located below the average level of the fluidized bed, at least one of the jets is directed vertically downward. 3. The method according to p. 2, characterized in that the processing process is conducted with a change in the flow rate of the jet directed vertically downward. 4. The method according to p. 1, characterized in that the jets are directed along intersecting paths oriented along the tangents to the surface covering the fluidized bed, or at an acute angle to the said tangents. 5. The method according to p. 1, characterized in that the jets of the supplied gas are directed along intersecting paths oriented along the tangents to the surface covering the fluidized bed, or at an acute angle to the said tangents, with some jets directed clockwise relative to the direction of the upward flow, and others counterclockwise. 6. The method according to p. 1, characterized in that the jets of the supplied gas are directed along intersecting paths oriented along the tangents to the surface covering the fluidized bed, or at an acute angle to the said tangents, some jets are directed clockwise relative to the direction of the upward flow, and others - counterclockwise, and the ratio of the flow rate of the jets supplied clockwise and counterclockwise during the processing process is changed. 7. A method of electrothermal processing of a dispersed material in a fluidized bed, in which a gas is supplied through a layer of dispersed material, upstream of which a fluidized bed is provided, and an electric current is passed, characterized in that during processing an additional mixing of the dispersed material in the fluidized bed is carried out by changing spatial distribution of electric current density. 8. The method according to p. 7, characterized in that during processing the electric current density is redistributed between different sections of the fluidized bed with a frequency of from 0.01 to 1000 Hz. 9. The method according to p. 7, characterized in that during processing the electric current passed through the fluidized bed is rectified and modulated with a frequency of from 0.01 to 1000 Hz. 10. The method according to p. 7, characterized in that the electric current passed through the fluidized bed is rectified and modulated with a frequency of from 0.01 to 1000 Hz, and the modulation depth is changed during processing. 11. The method according to p. 7, characterized in that the processing process is carried out, carrying out with a frequency of from 0.01 to 1000 Hz the reverse of the electric current passed through the fluidized bed. 12. The method according to p. 11, characterized in that the processing process is carried out by changing the frequency of the current reverse in the range from 0.01 to 1000 Hz. 13. The method according to p. 11, characterized in that the processing process is carried out by changing the duty cycle of pulses of positive and negative current polarity. 14. The method according to p. 7, characterized in that in the process of processing additionally pass the rectified current along the circuit covering the fluidized bed. 15. The method according to p. 14, characterized in that in the process of processing the rectified current passed through the circuit covering the fluidized bed is modulated with a frequency of from 0.01 to 1000 Hz. 16. The method according to p. 14, characterized in that the rectified current passed through the circuit covering the fluidized bed is modulated with a frequency of from 0.01 to 1000 Hz, and the depth and / or frequency of the modulation is changed during processing. 17. The method according to p. 7, characterized in that in addition to covering the fluidized bed circuit pass current, which is reversed with a frequency of from 0.01 to 1000 Hz. 18. The method according to p. 17, characterized in that in the process of processing the frequency of the reverse of the current passed through the circuit covering the fluidized bed is changed in the range from 0.01 to 1000 Hz. 19. The method according to p. 17, characterized in that the processing process is carried out by changing the duty cycle of the pulses of positive and negative polarity of the current passed through the circuit covering the fluidized bed. 20. The device for implementing the method according to claim 1, containing a lined vessel with a system for distributing and supplying a gas stream to the vessel to create a fluidized bed of dispersed material in an upward gas flow, electrodes, at least one of which is installed vertically in the vessel and immersed in a fluidized bed a layer, characterized in that the said electrode is made with an axial channel, and the gas flow distribution and supply system is made in the form of branches, at least one of which is connected to the axial channel of the said electrode . 21. The device according to p. 20, characterized in that the node modulation of the ratio of the flow rate of the gas stream supplied to the vessel through the distribution branches and the gas stream is introduced into the branch connected to the electrode with the axial channel. 22. A device for implementing the method according to claim 1, comprising a vessel with a lining, a gas distribution and supply system for fluidizing the dispersed material in an upward gas stream, characterized in that the vessel lining in the lower part is made in the form of a bowl in which there are connected to a system for distributing and supplying gas flow channels whose axes intersect in a vertical projection. 23. The device according to p. 22, characterized in that the lining bowl is made of horizontal plates installed with gaps forming channels for supplying gas. 24. The device according to p. 22, characterized in that the bowl of the vessel is made of plates arranged pyramidally inclined to the axis of the vessel at an angle of five degrees to an angle fifteen degrees greater than the angle of repose of the dispersed material. 25. The device according to p. 22, characterized in that the channels are parallel or at an acute angle relative to the faces or tangent to the inner surface of the bowl. 26. The device according to p. 25, characterized in that the channels are made at different levels with alternating directions clockwise and counterclockwise relative to the axis of the vessel. 27. The device according to p. 22, characterized in that the channels are located along the tangents to the inner surface of the bowl, are made at different levels with alternating clockwise and counterclockwise directions relative to the axis of the vessel, the channels of each of the directions are combined into a separate group from another groups by gas supply, and a modulation unit for the ratio of the flow rate of the gas stream through the channel groups is introduced into the gas flow distribution system. 28. The device for implementing the method according to claim 7, containing a lined vessel, a gas flow distribution and supply system, electrodes connected to the terminals of the power source, characterized in that one of the electrodes is made of sections isolated from each other, the power source is made with a conclusion , split into sections according to the number of sections of the electrode, and a current control system in sections, and each of the sections of the electrode is separately connected to the corresponding section of the output of the power source. 29. The device for implementing the method according to claim 7, containing a lined vessel, a gas flow distribution and supply system, electrodes connected to a DC power source, characterized in that it is equipped with an additional power source connected to an additional power source with a solenoid covering the area the location of the electrodes. 30. The device according to p. 29, characterized in that the additional power source is configured to modulate the rectified current or reverse the current with a frequency of from 0.01 to 1000 Hz.

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