MXPA00010578A - Method for conveying on high-density bed powder materials and device with potential fluidisation for implementing same - Google Patents

Abstract

The invention concerns a method for conveying a powder material (12) on high-density bed by potential fluidisation, using a device comprising at least an air pipe system (3) comprising a lower pipe (5) for circulating a fluidizing gas (G), an upper pipe (7) for circulating the powder material (12), the two pipes being separated by a porous wall (6), at least a pipe (8) supplying gas (G) and an adjusting column (4.1, 4.2) whereof the filling height (h) adjusts the potential fluidisation (pf) pressure. The invention is characterised in that it consists in generating in the upper pipe (7) of the air pipe system (3) a gas bubble (B1, B2) under pressure. Said bubble is durably located in said air pipe system (3) upper pipe (7) upper portion (14). The invention also concerns device for implementing the method and for regulating the gas bubble pressure.

Description

PROCEDURE FOR TRANSPORT IN HYBRID DENSE OF PULVERULENT MATERIALS AND DEVICE OF POTENTIAL FLUIDIZATION INTENDED FOR YOUR APPLICATION FIELD OF THE TECHNIQUE The invention relates to the transport of fluidizable powder materials. It is a horizontal or inclined transport that allows transporting the materials between a storage area and at least one area to be fed, the areas being remote from one another. It is a continuous powdery product transport process that allows to feed, from a single storage area, a large number of packaging sets such as baggers, containerization devices, or also a large number of production sets such as plastic extrusion presses or igneous electrolysis cell cells. The pulverulent materials to be transported are fluidizable: they have a granulometry and a cohesion such that insufflating a gas at low speed causes a de-cohesion of the particles between them and a reduction of the internal friction forces. Ref: 123776 This type of material is, for example, alumina used for igneous electrolysis, cements, gypsum, quicklime or slaked lime, fly ash, calcium fluoride, magnesium chloride, any filler for mixtures, catalysts, coal dust, sodium sulfate, phosphates, polyphosphates or pyrophosphates, plastic materials in powder form, food products such as milk powder, flours, etc.

ANTECEDENTS OF THE TECHNIQUE Numerous devices have been studied and developed for the fluidized bed transport of pulverulent materials. There is a particular problem with regard to the continuous feeding of the pulverulent material, regulated according to the consumption needs of the material. One of the examples among many that illustrates this problem is the example relating to the feeding in alumina of the igneous electrolysis cells for the production of aluminum.

For this, the alumina, a powdery product transported and solubilized in the bath, is doing the electrolysis and has to be replaced as it is being consumed, so that the concentration in Solubilized alumina is preserved at an optimum level, favorable to the maximum performance of the electrolysis cell. It is then necessary to regulate the amount of alumina introduced into the electrolysis cell, so that its operation is not disturbed by an excess or lack of alumina. The pulverulent material transport device developed by the applicant and described in European patent EP-B-0 179 055, allows a continuous feeding of powdery solid materials in hyperdense phase. It serves, among other things, to feed in alumina, in a regular and continuous manner, the storage and feeding hoppers located in the superstructure of the electrolysis tanks. It is a potential fluidization device, intended for the transport of pulverulent materials in a hyperdense bed, which allows these materials to be transported from a storage area to at least one area to be fed. As with classic fluidization, this device comprises, between the storage area and the area to be fed, at least one horizontal conveyor, called aero-channeling, constituted by a lower channel intended for the circulation of a gas, a upper channel intended for the circulation of the pulverulent material, both channels being separated by a porous wall. The lower channel is fed with gas through at least one supply conduit. Contrary to what is usually done with classic fluidization, the powdery material completely fills the upper channel of the conveyor and this conveyor is provided with at least one leveling column partially filled with pulverulent material, the filling height being what levels the gas pressure. This leveling column allows to create conditions of potential fluidization of the pulverulent material. The latter, little agitated because of the very low gas flow, is present in the aerocanalization in the form of a hyperdense bed. To better understand the potential fluidization, it is necessary to remember that it is the classic fluidization, which is usually applied in the transport of pulverulent materials, and described for example in the patent US 4 016 053. The device used in fluidization also includes an aero-airization, as the one that we have described previously. The fluidizing gas ba or a given pressure pf is introduced into the lower channel, passes through the porous wall and then between the particles at rest of the powdery material forming the layer to be fluidized. Contrary to the potential fluidizing device described in EP 0 179 055, the thickness of this layer at rest is much lower than the height of the upper channel of the conveyor, that is to say that when there is no injection of fluidizing gas, the powdery material only the upper channel of the horizontal conveyor arrives in part. Applying an important gas flow, the particles move and rise, each losing the points of permanent contact with the others. Therefore, the interstitial space between the particles increases, the internal frictions between particles decrease and these particles are in a state of dynamic suspension. This results in an increase in the initial volume of the pulverulent material and, correlatively, a decrease in the bulk density, since a suspension of a solid phase is formed in a gas phase. The bulk density of the material is therefore less important compared to that existing in potential fluidization, such as that described in EP 0 179 055, in which the term "hyperdense phase" is used. The word < < dense phase > > it is usually applied to high pressure pneumatic transport. The phase Hyperdensity is characteristic of potential fluidization. To make it clearer, it is considered for example in the case of alumina Al203 that the solid / gas ratio is of the order of 10 to 150 kg Al203 / kg air in the case of pneumatic transport in dense phase and from 750 to 950 kg A1203 / kg air in the case of transport due to potential fluidization in the hyperdense phase. The hyperdense phase thus allows the pulverulent solid to be transported at very high solid / gas concentrations, much higher than the dense phase in pneumatic transport. In the case of fluidization, even when there is no gas injection, the pulverulent material almost completely fills the transport device, in particular the upper channel. When the gas is introduced into the lower channel, the leveling column is partially filled with the powdery material that occupies the upper channel, according to a manometric height that levels the pressure pf and prevents the increase of the interstices between the particles. Therefore, the presence of the leveling column prevents fluidization of the pulverulent material present in the horizontal conveyor and forces the material to appear in the form of a hyperdense bed of potential fluidization. In addition, by not increasing the interstitial distance between the particles, the permeability of the medium to the gas introduced under the pressure pf is very low and the gaseous flow is very weak. In the following, we will call this low gaseous flow passing through the leveling column < < degassing > > . Thus, with a fluidization pressure pf of 80 millibars, the velocity of the gas in circulation corresponding to the pressure pf and causing the fluidization of pulverulent alumina is of the order of 33 10"3 ms ~" in the device described in US 4 016 053, while, in the potential fluidizing device of EP-B-0 179 055, the velocity of the gas in circulation is only of the order of A 10 ~ 3 ms "1. This velocity is too low to be able to cause fluidization of alumina in the conveyor assembly.

Although there is no fluidization, it can be said that there is a partial fluidization: if there is no permanent circulation of the material inside the aerocanalization, there is a spill due to successive detachments when there is a need for pulverulent material, for example when the level of the zone to feed is below a critical value. In fact, when the continuous consumption of the material stored in the area to be fed is such that the level of the material falls and reaches below the orifice of the feed pipe, a certain amount of the powdery material escapes from the pipe, creating an < < empty > > that is filled thanks to a detachment of the material, detachment that produces another detachment upstream and that is repeated in this way little by little within the airflow to the storage site. The potential hyperdense bed fluidization fluidization device, as described in EP-B-0 179 055, is exploited on a large scale, especially to feed the 300,000 ampere vats of the recent facilities that perform the igneous electrolysis of aluminum . The advantages of this device are well known: • a continuous feeding of the tanks that allows to keep the hoppers always full, • a low maintenance of the system, • air pressures necessary for relatively low fluidization (0.1 bar compared to 6 for transport) dense phase tire), • a low velocity displacement of the alumina which limits the wear of the material and the friction or agglomeration of the product.

BRIEF DESCRIPTION OF THE INVENTION Although the device described in EP-B-0 179 055 presents all the mentioned advantages, it can also present some drawbacks if certain particular precautions are not taken: • a fluidization gas consumption, and therefore of non-optimized energy, • take-offs, is say of the important alumina recycles by the leveling columns, • a risk of granulometic segregation by preferential takeoff of the finest particles.

In addition, in an electrolysis workshop, the number of areas to be fed from a single storage area is important (several tens) and the distance between the storage area and the area to be fed can also be important (several hundred meters) ). To alleviate these drawbacks, the applicant has proposed the device illustrated in EP-B-0 179 055, formed by a series of staggered conveyors: a first conveyor that joins the storage area with a series of secondary conveyors, each corresponding to a tank and provided with side holes that feed the hoppers integrated into the superstructure of the Cuba. Although these air-channels, especially the first conveyor, are provided with numerous leveling columns, it can be observed in certain operating conditions: • an instable operation with the risk of total blockage of the airflow when the degassing is not done or when it is only partly done in one of the leveling columns, • a random control of the alumina in the aerocanalization and in the leveling column, which can produce a power failure in extreme cases.

DESCRIPTION OF THE INVENTION The method according to the invention is a process for transporting pulverulent materials in a hyperdense bed by potential fluidization, using a device comprising at least one air channeling provided with a lower channel for the circulation of a fluidizing gas, of an upper channel intended for the circulation of a fluidizing gas. to the circulation of the pulverulent material, both channels being separated by a porous wall, at least one fluidization gas supply conduit and a column of leveling whose level of filling levels the potential fluidization pressure, characterized in that a bubble of gas under pressure is created in the upper channel of the aero-channelization. Preferably, an attempt will be made to create a bubble in everything that is the aerocanalization, except the upper part of the upper channel located near the leveling columns. Preferably, it will be attempted to durably maintain the bubble thus created near the upper part of the upper channel. Another object of the invention is a device that allows to create, control and regulate the volume and the pressure of the fluidization gas bubble maintained in the upper part of the upper channel of the aerocanalization. Even if the number of zones to be fed is important, the method according to the invention makes it possible to maintain in the state of potential fluidization the entire part of the aero-channel located between the storage area and a zone to be fed. This method is characterized in that the pressure of the bubble formed according to the invention is applied in the upper part of the upper channel so that the level of the powdery product within the leveling column located near the bubble is maintained at the predetermined set value.

Without the improvement provided by the method according to the invention, it sometimes happens that the circulation of the fluidizing gas through the pulverulent product is random, the risk being so much greater than the distance between the storage area and the areas to be fed represents several. hundreds of meters and that the number of areas to be fed from a single storage area is important. Even if the aerocanalizations are provided with several leveling columns, it sometimes happens that certain zones are not in a situation of potential fluidization, which can cause catastrophic consequences, mainly when it comes to continuously feeding an igneous electrolysis cell. The Applicant has observed with surprise that when the upper part of the aerocanalization is not filled with pulverulent material, the fluidizing gas can circulate more easily, which improves the potential fluidization conditions with which it must be fulfilled in everything that is the aerocanalization. According to the method of the invention, a fluidization gas bubble is created in the upper part of the aero-channelization, at least remote from the leveling columns, because the powdery material must be able to rise freely by the spine. It's also about creating a bubble < < stable > > to avoid spills or untimely detachments of powdery material. There are thus two distinct phases in the upper channel of the conveyor: • a fluidized or potential fluidizing phase which is a mixture of pulverulent solid and fluidizing gas, located in the lower part of the aero-channelization, • a different phase mainly formed by gas of fluidization that circulates in the upper part of the conveyor. This phase is what represents the < < bubble > > . As in the case of classical fluidization, the upper channel of the aero-channelization is not completely filled by the powdery material to be transported, but the great difference between the device used to apply the method according to the invention and a classical fluidization aero-channelization, lies in the fact that the gas bubble that is above the upper level of the powdery material is still present after the pressurization. This pressure directly links to the level of pulverulent material located within the nearby leveling column.

To create bubbles, for example barriers such as flat irons or other geometric shapes are introduced as a circular or polygonal penetration of the leveling columns. You can also combine the implantation of flat irons and the penetrations of the leveling columns. The space occupied by the gas bubble depends on the width of the airflow, the height and the arrangement of the barriers. This height is usually between one-hundredth and one-half the height of the useful part of the aero-channeling that carries the powdery solid. In fact, if this height is less than a hundredth of the height of the useful part of the aero-channelization, the gas will have difficulty in circulating freely and the bubble is not effective. If this height is greater than half the height of the useful part of the aero-channelization, the circulation of the powdery product is limited and the height of the aero-channeling is increased unnecessarily with the same flow of product transported. Ideally, the height of the bubble is, for example, 50 mm in the case of a traditional aero-channeling. The arrangement of the barriers depends on the total length of the airflow and the number of leveling columns. It usually takes like minimum one barrier for each leveling column. However, the system can operate with a number of barriers lower than the number of leveling columns. Preferably each bubble corresponds to a leveling column. The bubble is thus delimited in space by the upper wall of the upper channel of the aero-channel, the flat irons forming a barrier and / or the penetration of at least one leveling column. The other border is the upper level of the powdery material. Apart from this last frontier, the set of walls is fixed, which allows to locate the bubble in a lasting way, that is to say stabilize and fix its positioning in perfectly defined limits. This avoids any risk of sudden displacement of the bubble, which could cause a spill or an untimely detachment of the pulverulent material in the aerocanalization, or a crazy blockage due to the complete filling of the upper channel section of the aerocanalization with the powdery material . The bubble is subjected to a pressure directly linked to the level of the pulverulent material that fills the corresponding leveling column. When the number of barriers is less than the number of leveling columns, the bubble is associated with several columns, filled with a level of pulverulent material quite equivalent. By locally controlling the volume and the pressure of the bubbles, the fluidization pressure can be regulated at any point of the aerocanalization.

When the bubble is created, it is possible to adjust the height of alumina in the leveling column. The relationship between the bubble pressure and the alumina height is obtained with the following formula: Pb = h * d with h = height of alumina in the leveling column d = average apparent density of the alumina. The fluidization pressure pf is the pressure that rears in the lower channel of the aero channel and which allows a potential fluidization of the pulverulent material in the upper channel. The bubble pressure is linked to the fluidization pressure by the following simplified formula: Pf =? Pp + hl * d + Pb with? Pp = loss of load in the porous wall Hl = height of alumina in the aero-channelization? Pp practically follows constant since it is not function but of the thickness of the porous wall and the velocity of the gas. It is enough then to regulate the fluidization pressure with a servo control based on the measurement of the bubble pressure to maintain the height of alumina in the leveling column at a controlled level, according to a predefined setpoint value. This regulation is carried out practically using a pressure transmitter and a pressure gauge that measures the pressure of the bubble, to which corresponds a valve for automatic regulation of the fluidization pressure. Thus, the control of the bubble pressure makes it possible to adjust the fluidization pressure to an optimum value in order to maintain the system in a state of potential fluidization. In this way any excess gas in the system is avoided and, consequently, it is impossible to minimize the energy consumption necessary for the fluidization. In practice, it has been sought to maintain a slightly positive bubble pressure to minimize the amount of gas introduced while retaining a sufficient height of alumina in the leveling column. Generally, care will be taken to maintain a constant bubble pressure between 1 and 50 mbar and preferably between 5 and 50 mbar.

The bubble pressure can be measured at any point of the aerocanalization but it is at the end of the aerocanalization where it is preferable to make this measurement since it can thus be verified that the aerocanalization is full of powdery material to be transported. With the mere indication that the bubble pressure is positive at this point, it is verified that the system works correctly and that all the areas to be fed are effectively fed. When the bubble pressure is adjusted as indicated above, it is observed: • a constant level of the alumina in the leveling columns, • a scarce, even nil, takeoff of the solid particles, due to the scarce gas flow necessary for the regulated fluidization, • an absence of granulometric segregation along the airflow, • a regular spillage of dust. The aero-channelization is kept full of product at every moment, avoiding in this way any risk of breakage of supply, • a minimum energy consumption for all the fluidization gas production machines.

MODE FOR CARRYING OUT THE INVENTION - EXAMPLE The method according to the invention will become clearer with the detailed description of a conveying device for horizontal bubble pressure aerocanalization in the hyperdense system used for the feeding of modern aluminum electrolysis tanks. This device is set forth below by way of non-restrictive example. Figure 1 is a schematic view in vertical section of the device according to the invention which consists here of a horizontal aero-channeling, which may symbolize a portion of primary conveyor or secondary conveyor, which joins the storage device to an evacuation system and integrates a flat iron that forms a barrier and separates two bubbles corresponding each of these to a leveling column. Figure 2 is a diagram of the principle reaction of the regulation of the fluidization pressure, carried out using a pressure transmitter and a pressure gauge that measures the bubble pressure and corresponds to a valve for automatic regulation of the fluidization pressure.

Figure 3 is a reaction scheme illustrating the example set forth below with a particular arrangement of leveling columns and barriers. The device of figure 1 is composed of an air storage tank 1 of the material to be transported, connected by a pipeline 2 to a conveyor 3 of the aerocanalization type or fluidization aerocarpl, by leveling columns 1 and 2, by an evacuation system 9 of the conveyor, which, by means of a controlled dosing system 10, brings the pulverulent material towards the area to be fed 11. The air storage tank 1 contains the pulverulent material 12 in bulk, subjected to atmospheric pressure. This tank is loaded on one of the ends of the horizontal (or inclined) conveyor 3 by means of the duct 2. The long-length conveyor 3 consists of a porous wall 5 separating the lower channel 6 and the upper channel 7 for circulation of the powdery material. A fluidizing gas G is introduced through a pipe 8 into the lower channel 6, where it is subjected to the fluidization pressure pf. This gas passes through the porous wall 5, also called fabric, and through the powdery material that fills the upper channel 7 of the conveyor. The low gas evacuation flow (DI, D2) as it passes through the pulverulent material that partially fills the leveling columns 4.1 and 4.2 up to levels 15.1 and 15.2, according to a manometric height h that levels the gas pressure pf. The barrier is a flat iron 50 that separates the upper part of the upper channel 7 in two, thus forming two bubbles Bl and B2. The volume of these bubbles is perfectly delimited in the space by the wall of the upper part 14 of the upper channel 7, the flat iron 50, the penetrations 40.1 and 0.2 of the leveling columns 4.1 and 4.2 and the upper level 13 of the powdery material 12. Figure 1 illustrates how the circulation of the fluidising gas G passes through the fabric 6 and is directed towards the leveling columns 4.1 and 4.2 on both sides of the barrier 50. Recall that Figure 1 illustrates two leveling columns associated with a barrier, but it is clear that for longer aerocanalizations, the number of columns and barriers will be more important. The aerocanalization is provided with a means of evacuation 9 that transforms the movement horizontal of the pulverulent material in a vertical or very inclined movement which allows to feed either a secondary conveyor, if the aerochanalization is a primary conveyor, or is a hopper integrated into the superstructure of an electrolysis cell, if the aerochanalization is a secondary conveyor. The hoppers are equipped in their lower part with controlled dosing systems 10 which allows introducing the desired amounts of alumina in the tank. In the present example, the primary conveyor is a 400 m long horizontal aircanalization fed with alumina from a storage site located at its center. The number of tanks fed by the aero-channeling is 72: there are 72 secondary conveyors that feed the integrated hoppers to the superstructure of each of the 72 tanks. The primary conveyor is equipped with 36 leveling columns and an equivalent number of barriers. The bubble pressure measured at the end of the airflow is 10 mbar. It is kept constant thanks to a regulation of the fluidization pressure.

Figure 2 illustrates how the fluidization pressure pf can be regulated by measuring the bubble pressure pb inside the bubble B to maintain a controlled level, with respect to a desired setpoint value h, of the alumina in the leveling column 4.

This regulation is obtained using a pressure transmitter 80 together with a pressure gauge that measures the bubble pressure pb to which corresponds an automatic fluidization pressure regulating valve 81 which controls the output of the fluidization gas G through the line 8. Whereby, the control of the pressure pb makes it possible to regulate the fluidization pressure pf at an optimum value which makes it possible to maintain the system in a state of potential fluidization. The bubble pressure can be measured at any point of the aerocanalization but it is at the end of the aerocanalization where it is preferable to make this measurement since in this way it can be verified that the aerocanalization is full of alumina. The mere fact that the bubble pressure is positive at this point indicates that the system is functioning correctly and that all the tanks are powered.

The reaction scheme of figure 3 indicates the relative arrangement of the leveling columns and of the barriers for creating the bubble pressure for a preferable operation of the hyperdense phase system, in the case of an installation comprising 2 electrolysis tanks and n leveling columns. In the example shown, the number n is 36. The iron 50.1 separates the bubbles Bl and B2. It is located a bit further under column 4.1. The bubble Bl corresponds to the evacuation means 9.1 which symbolizes two secondary conveyors feeding each one a tank. Also, the flat iron 50. (n-l) separates the bubbles B "-? and Bn. It is located slightly below the leveling column 4. (n-l). To the bubble Bn there corresponds an evacuation means 9.n which symbolizes two conveyors feeding the tanks 2n-1 and 2n respectively. The barrier 50.n is confused with the end wall 90 of the conveyor, located in front of the last leveling column 4.n. The pressure transmitter 80 is located near the end 90 of the aerocanalization 3: the regulation of the fluidization pressure pf is based on a measurement made in the bubble B "located at the end of the aero-channelization, that is to say capable of being the lowest pressure.

ADVANTAGES OF THE PROCEDURE ACCORDING TO THE INVENTION • a constant level of the alumina in the leveling columns, • a scarce, even zero, takeoff of the solid particles, due to the low gas flow required for the regulated fluidization, • an absence of granulometric segregation along the airflow, • a spill, and a regular supply of dust. This advantage is particularly important for igneous electrolysis tanks of aluminum, • a minimum energy consumption for all fluidization gas production machines.

It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Claims (16)

1. Having described the invention as above, the content of the following claims is claimed as property: 1. Procedure for transporting a pulverulent material in a hyperdense bed by potential fluidization, with a device comprising at least one air channel that integrates a lower channel intended for the circulation of a fluidizing gas, a top channel intended for the circulation of a powdery material, both channels being separated by a porous wall, at least one gas supply pipeline and a leveling column whose level of filling levels the pressure of potential fluidization, characterized in that by applying the fluidization pressure in the aerocanalization, a bubble of gas or pressure is formed in the upper channel of the aero-channelization.
2. 2. Method of transporting a pulverulent material in a hyperdense bed by potential fluidization according to claim 1, characterized in that the bubble is permanently located in the upper part of the upper channel of the aero-channelization.
3. 3. Process for transporting a pulverulent material in a hyperdense bed by potential fluidization according to claim 1 or 2, characterized in that the bubble is formed and maintained in the upper part of the upper channel of the aerocanalization by placing walls making a barrier, resulting in the low pressure or pressure of the bubble of the putting under fluidization pressure of the aerocanalization.
4. 4. Process for transporting a pulverulent material in a hyperdense bed by potential fluidization according to any of claims 1 to 3, characterized in that the gas bubble under pressure corresponds to at least one leveling column.
5. 5. Method of transporting a pulverulent material in a hyperdense bed by potential fluidization according to any of claims 1 to 4, characterized in that the potential fluidization pressure is regulated by servo control in the bubble pressure.
6. 6. Procedure for transporting a pulverulent material in a hyperdense bed by fluidization potential according to claim 5, characterized in that the bubble pressure is measured at one end of the aero-channelization.
7. 7. Process for transporting a pulverulent material in a hyperdense bed by potential fluidization according to claim 5, characterized in that the bubble pressure is between 1 and 500 mbar and preferably between 5 and 50 mbar.
8. 8. Method of transporting a pulverulent material in a hyperdense bed by potential fluidization according to any of claims 5 to 7, characterized in that a pressure transmitter is used together with a pressure gauge that measures the bubble pressure corresponding to an automatic regulation valve of the fluidization pressure that controls the fluidization gas outlet through the pipeline.
9. 9. Device for transporting a pulverulent material in a hyperdense bed by potential fluidization comprising at least one aero-channelization, with a lower channel for the circulation of a fluidizing gas, an upper channel intended for circulation of the pulverulent material, both channels being separated by a porous wall, as well as at least one gas supply pipeline and a leveling column whose level of filling levels the potential fluidization pressure, characterized in that the upper part of the upper channel of the Aero-channeling is provided with at least one barrier, for example in the form of a flat iron.
10. 10. Device for transporting a pulverulent material in a hyperdense bed by potential fluidization according to claim 9, characterized in that the barrier or each barrier contributes to the creation and lasting maintenance of a gas bubble under pressure in the upper part of the upper channel of the aero-channelization when it is put under potential fluidization pressure the aerocanalization.
11. 11. Device for transporting a pulverulent material in a hyperdense bed by potential fluidization according to claim 9 or 10, characterized in that the barrier or each barrier occupies between one hundredth and one half of the height of the upper channel.
12. 12. Device for transporting a pulverulent material in a hyperdense bed by potential fluidization comprising at least one aerocanalization, with a lower channel intended for the circulation of a fluidizing gas, an upper channel intended for the circulation of the pulverulent material, both channels being separate by a porous wall, as well as at least one gas supply duct and a leveling column whose filling level levels the potential fluidization pressure, characterized in that the leveling column is extended in the aero-channelization by a penetration.
13. 13. Device for transporting a pulverulent material in a hyperdense bed by potential fluidization according to claim 12, characterized in that the penetration contributes to the formation and lasting maintenance of a gas bubble under pressure in the upper part of the upper channel of the aero-channelization, when the aero-channelization is placed under potential fluidization pressure.
14. 14. Device for transporting a pulverulent material in a hyperdense bed by potential fluidization according to claim 12 or 13, characterized in that the penetration of the leveling column has a height between one hundredth part and one half of the height of the upper channel.
15. 15. Device for transporting a pulverulent material in a hyperdense bed by potential fluidization according to any of claims 9 to 11 and any of claims 12 to 14, characterized in that the height of the barrier or of each barrier and that of the penetrations of the Leveling columns are quite equivalent and determine the height of the bubble or each gas bubble under pressure.
16. 16. Device for transporting a pulverulent material in a hyperdense bed by potential fluidization according to any of claims 9 to 15, characterized in that the number of barriers is lower or equivalent to the number of leveling columns.