EP3366751A1 - Process and apparatus for the partial oxidation of organic material in a pulverized feed material - Google Patents

Abstract

The invention relates to a method and a device for the at least partial pyrolysis and at least partial oxidation of an organic fraction of a dusty or dusty bulk material of at least partially organic origin, wherein in the process dust raising is at least substantially avoided.

Description

The invention relates to a method and a device for at least partial pyrolysis and at least partial oxidation and optionally partial gasification of an organic portion of a dusty bulk material of at least partially organic origin. The at least partial pyrolysis or the at least partial oxidation may each independently be a complete or a partial pyrolysis or oxidation. In the gasification, carbon contained in the organic fraction is partially oxidized and turned into water gas with water or water vapor, i. H. a mixture of carbon monoxide and hydrogen reacted. Important in the process is that the product of the process contains phosphorus contained therein in easily usable form for plants. The organic origin may be at least one human, at least one animal, at least one plant, at least one alga and / or at least one fungus. The organic origin can also be of microbial origin. All bulk materials, at least partially of organic origin, contain carbon and phosphorus. The bulk material can z. As sewage sludge, animal excrement, algae, peat or lignite each in at least partially dried form or sawdust include. The bulk material may contain an inorganic component, eg. B. in the form of fine sand or minerals, of up to 70 wt .-% have.

The problem with the conventional mono-incineration of sewage sludge is that the ashes usually resulting from the prevailing temperature of more than 850 ° C initially softened and even sintered or glazed at a temperature of about 950 ° C. The phosphorus contained in the ash is then no longer available in a usable form for plants.

From the EP 3 037 395 A1 are already known a method and an apparatus for obtaining a product when gasifying a bulk material of at least partially organic origin under at least partial oxidation of the bulk material, wherein the product contains phosphorus in easily usable form for plants. In the method, a bed of bulk material is introduced into a reaction space of a reactor and moved therein continuously or intermittently. The bulk material is heated on the top of the bed to a temperature at which it comes to a pyrolysis of the organic content of the bulk material. Furthermore, air or another oxygen-containing gas mixture is blown into the bed via at least one injection opening in at least one tool moving continuously or intermittently through the bed. In this case, the injection of air or other gas mixture is controlled so that the amount of air or the gas mixture is sufficient only to an incomplete oxidation of the organic content of the bulk material in the reaction space. In the process, the bulk material is supplied to the reaction space from above and discharged below in the reaction space. In the method, the injected and the resulting gas move in ascending order in the reaction space and the bulk material descending in the opposite direction. The method has proven itself for evenly from the gas flowable bulk material.

From the CH 684961 A5 is a deck oven for sludge and waste incineration known. The furnace has a plurality of annular, one above the other arranged hearth, via which the kiln is fed by means of equipped with inclined stirrup teeth Krählarme alternately radially inwards and outwards and to the next lower hearth. The uppermost stoves serve for drying and the lowest flocks of slag or ash cooling. The stoves have alternating inside and outside diarrhea. The stirrers on successive Krählarmen have an alternately inward and outward employment. As a result, the fuel and dry material is alternately pushed back and forth and thus promoted slowly over the herd. The combustion air can be introduced via a hollow shaft in the hollow Krählarme, which are provided in the vicinity of the stirring teeth with outlet openings, in the deck oven. When operating the ovens with a dusty or dusty bulk but it comes to Staubaufwirbelungen.

Object of the present invention is to provide an alternative method for at least partial pyrolysis and at least partial oxidation of an organic content of a dusty or dusty bulk material of at least partially organic origin, which is a relatively uniform oxidation of the organic content of the bulk material and a relatively low dust load in the resulting flue gas allows. Furthermore, a device suitable for carrying out the method should be specified.

The object is solved by the features of claims 1 and 15. Advantageous embodiments result from the features of claims 2 to 14.

According to the invention, a process is provided for at least partial pyrolysis and at least partial oxidation of an organic fraction of a dusty or dusty bulk material of at least partially organic origin. The bulk material may be a bulk material which behaves like or at least similar to a fluid. The term "bulk material" designates here and below not only the bulk material used in the process but also any solid free-flowing intermediate product or product which arises during the process from the originally used bulk material, which may also comprise ash. The bulk material can be present in non, partially or completely pyrolyzed and / or non, partially or completely oxidized form.

1. a) Einbringen einer Schüttung des Schüttguts in einen Reaktionsraum eines Reaktors, wobei das Schüttgut auf einer ersten Reaktionsfläche im Reaktionsraum aufgebracht und mittels eines ersten Ausbreitungs-, Durchmischungs- und Bewegungsmittels ausgebreitet, durchmischt und zu einem Leitungsmittel hin und optional in das Leitungsmittel hinein bewegt und dabei von oben auf eine Temperatur erhitzt wird, bei der es zu einer vollständigen oder teilweisen Pyrolyse des organischen Anteils des Schüttguts kommt, wobei das Schüttgut in einer Bewegungsrichtung auf dem oder durch das Leitungsmittel auf eine zweite Reaktionsfläche in dem Reaktionsraum oder einem weiteren Reaktionsraum übergeleitet wird,
2. b) Ausbreiten, Durchmischen und Bewegen des Schüttguts auf der zweiten Reaktionsfläche mittels eines zweiten Ausbreitungs-, Durchmischungs- und Bewegungsmittels, wobei das Schüttgut zu einem Ausleitmittel oder Überleitungsmittel hin und optional in das Ausleitmittel oder Überleitungsmittel hinein bewegt wird, wobei das Schüttgut mit einem Sauerstoff enthaltenden Gasgemisch in Kontakt gebracht wird, so dass dabei die zumindest partielle Oxidation des organischen Anteils des Schüttguts erfolgt,
3. c) Ausbringen des resultierenden zumindest partiell oxidierten Schüttguts aus dem Reaktionsraum oder dem weiteren Reaktionsraum, durch das Ausleitmittel,

wobei das Schüttgut dadurch mit dem Gasgemisch in Kontakt gebracht wird, dass es von oben und/oder von einer Seite her so mit dem Gasgemisch beaufschlagt wird, dass das Gasgemisch das Schüttgut überströmt, ohne die Schüttung des Schüttguts zu durchströmen. Das bedeutet, dass das Beaufschlagen der Schüttung mit dem Gasgemisch so sanft erfolgt, dass sich das Gasgemisch keinen Weg durch die Schüttung sucht und das Schüttgut nicht oder zumindest nicht wesentlich aufgewirbelt wird. Im Reaktionsraum ist oberhalb der ersten Reaktionsfläche eine Gasauslassöffnung angeordnet. Dadurch strömt das Gasgemisch nach dem Kontakt mit dem Schüttgut im Reaktionsraum nach oben. Üblicherweise bewegt sich das Schüttgut dagegen der Schwerkraft folgend im Reaktionsraum vom Einbringen in den Reaktionsraum bis zu Ausbringen aus dem Reaktionsraum nach unten.The method comprises the following steps:

1. a) introducing a bed of bulk material in a reaction space of a reactor, wherein the bulk material applied to a first reaction surface in the reaction space and spread by means of a first propagation, mixing and moving means, mixed and moved to a conduit means and optionally into the conduit means and It is heated from the top to a temperature at which it is a complete or partial pyrolysis of the organic portion of the bulk material, wherein the bulk material is transferred in a direction of movement on or through the conduit means to a second reaction surface in the reaction space or another reaction space,
2. b) spreading, mixing and moving the bulk material on the second reaction surface by means of a second spreading, mixing and moving means, wherein the bulk material is moved to a discharge means or transfer means and optionally into the discharge means or transfer means, wherein the bulk material with an oxygen containing gas mixture is brought into contact, so that there is at least partial oxidation of the organic content of the bulk material,
3. c) applying the resulting at least partially oxidized bulk material from the reaction space or the further reaction space, by the discharge means,

wherein the bulk material is brought into contact with the gas mixture in that it is acted upon from above and / or from one side so with the gas mixture that the gas mixture flows over the bulk material, without flowing through the bulk of the bulk material. This means that the loading of the bed with the gas mixture takes place so gently that the gas mixture does not seek a way through the bed and the bulk material is not or at least not significantly stirred up. In the reaction space, a gas outlet opening is arranged above the first reaction surface. As a result, the gas mixture flows after contact with the bulk material in the reaction chamber upwards. Usually, however, the bulk material moves following the gravity in the reaction chamber from the introduction into the reaction chamber until it is discharged from the reaction chamber down.

Furthermore, it is completely or at least substantially prevented that a flow of the gas mixture that moves on or through the conduit means Crude material crosses or flows through or that the gas mixture flows through the conduit opposite to the direction of movement of the bulk material.

For generating water gas, the gas mixture may optionally contain water in the form of steam or an aerosol. Alternatively, the bulk material may be contacted with water other than the gas mixture.

The introduction according to step a) can take place continuously or intermittently. The bulk material introduced into the reaction space can be applied directly to the first reaction surface. However, it is also initially possible to apply at least one reaction surface upstream of at least one of the first reaction surfaces and from there to reach the first reaction surface.

The mixing and agitation in steps a) and b) can be carried out independently of one another continuously or intermittently. The transfer of the bulk material on or through the conduit means and the discharge of the bulk material from the reaction space or the further reaction space by means of the discharge can each independently by taking advantage of gravity or by active promotion, for example by means of a screw conveyor. The sour gas containing gas mixture may be air.

The gas mixture, after it has been brought into contact with the bulk material, can also comprise an oxidation gas formed during the at least partial oxidation and, if appropriate, also a combustion gas formed during combustion thereof and no or at least less oxygen than originally. Usually, the bulk material follows the course of the process of gravity, so that the discharge is usually arranged in the lower part of the reaction space and below the second and possibly further reaction surface / s.

A gas outlet opening for the gas mixture is usually in the upper part of the reaction space and above the first and possibly at least one of the first Reaction surface upstream reaction surface arranged. After it has been brought into contact with the bulk material, therefore, the gas mixture usually flows upwards in the reaction space while flowing around all of the reaction surfaces.

The inventors of the present invention have recognized that in the method according to the EP 3 037 395 A1 When reacting a dusty or dusty bulk material by poor flowability of such bulk material to a strong gas pressure drop in the bed and partly to the formation of flow channels and to considerable Staubaufwirbelungen comes. The formation of flow channels leads to uneven and thus difficult to control oxidation processes in the reaction chamber and to a high dust load in the resulting flue gas. The high dust load is accompanied by a relatively high maintenance requirement.

Furthermore, the inventors have recognized that in the method according to the EP 3 037 395 A1 by the bed moving tool subject to a relatively high wear.

An essential advantage of the method according to the invention is that the formation of dust suspended in gas is at least largely avoided. The dust load of the resulting exhaust gas in the process is thereby significantly reduced. This is achieved in that it is avoided that a gas stream crosses a flow of the bulk material flows through it or flows against it and the gas thereby entrains the dust covered by the bulk material. This is achieved by completely or at least substantially preventing a flow of the gas mixture from crossing or flowing through the bulk material moving on or through the conduit means, or that the gas mixture flows through the conduit means counter to the direction of movement of the bulk material. Furthermore, it is achieved by bringing the bulk material into contact with the oxygen-containing gas mixture in such a way that it is supplied with the gas mixture from above and / or from one side, that the gas mixture overflows the bulk material without flowing through the bulk of the bulk material. The gas mixture is therefore not as in the from EP 3 037 395 A1 blown known methods in the bulk material.

The temperature to which the bulk material is heated, so that it comes to a pyrolysis of the organic content of the bulk material, is usually at least 250 ° C. The temperature depends on the type of bulk material. For sawdust, 250 ° C may be sufficient, while dried sewage sludge may require at least 500 ° C. The temperature may be in a heating medium, for example by an electric heating rod or an electric heating coil or other electrical heating, a heating chamber heated by gas or oil and / or by burning the resulting gas in the pyrolysis or by the incomplete oxidation of the bulk material above the bed , in particular in a combustion chamber, are generated. The heating of the bulk material to a sufficient temperature for pyrolysis of the organic content of the bulk material is sufficient to cause an oxidation of the organic content of the bulk material by blowing in the gas mixture and thereby at least maintain the temperature in the bulk material or even increase. For combustion of the gas formed during pyrolysis or by incomplete oxidation of the bulk material, the gas mixture or a further oxygen-containing gas mixture can be supplied to the reaction space.

By the method according to the invention, it is possible to gasify the bulk material at a relatively low temperature in the range of 250 ° C to 850 ° C, in particular 300 ° C to 800 ° C, without causing temperature peaks above this range and thus to a Softening, sintering or vitrification of the ashes comes. The resulting product is relatively homogeneous and has good availability of the phosphorus for plants contained therein. The resulting gas can be burned in a / the combustion chamber with the formation of combustion gas. In this case, a temperature of at least 850 ° C can be achieved. The combustion gas can be maintained at this temperature with a residence time of at least two seconds, thereby the requirements of the 17th Ordinance to Implement the Federal Immission Control Act of the Federal Republic of Germany can be met. The resulting combustion gas is loaded with a relatively low dust content. At the same time, the energy required to pressurize the bulk material with the gas mixture from above and / or from the side is significantly lower than when the gas mixture is blown into the bulk material, as is known from US Pat EP 3 037 395 A1 is known. Another advantage of the loading of the bulk material from above and / or from the side with the oxygen-containing gas mixture with simultaneous mixing of the bulk material is that the oxidation of the bulk material is much more uniform than when blowing the gas mixture into the bulk material. When injecting the gas mixture into the bulk material, gas channels can form, which then lead to a locally enhanced reaction or oxidation and a concomitant local overheating and thus local softening, sintering or vitrification of the ash in the bulk material. The high dust load in the resulting combustion gas also leads in the prior art to a relatively high maintenance requirement. In addition, today's legal requirements require complex procedural measures to remove the dust from the combustion gas. In addition, moving in the bulk material moving stirring and injection tools are subject to high wear. This causes an additional increased maintenance and relatively high operating costs.

In order to prevent the formation of dust, the flow of the gas mixture in the process according to the invention is conducted in such a way that it does not cross or flow through the bulk material, in particular in the region of the transfer to the second reaction surface, or if it flows counter to the bulk material through the conduit means. Furthermore, it is advantageous for avoiding the stirring up of dust if the second spreading, mixing and moving means is independent of a means for charging the bulk material with the gas mixture.

In one embodiment of the method is thereby completely or at least substantially prevented that a stream of the gas mixture located on the or by the bulk material moving bulk material crosses or flows through, that the conduit means is formed at least partially in the form of a channel, a channel or at least one side limited by a first protective wall first sliding surface. Since the gas mixture usually flows into the reaction space on the reaction surfaces inside or outside past after contact with the bulk material, the conduit means formed at least partially in the form of a groove or a first sliding surface bounded at least on one side by the first protection wall can provide protection on or Offered by the conductive means bulk material against the flow of the gas mixture from below and at least from the side of the first protective wall ago. This protection is sufficient to completely or at least substantially prevent a stream of the gas mixture from crossing or flowing through the bulk material.

It is also possible that thereby completely or at least substantially prevents the gas mixture from flowing through the conduit means counter to the direction of movement of the bulk material, that the conduit means has a closing mechanism or lock mechanism passable in the direction of movement for the bulk material, which opposes the gas mixture the direction of movement is not or essentially not passable. The closing mechanism may, for example, comprise a flap which opens under the weight of the bulk material or is opened by active control or actuation to let the bulk material through and then close again or be closed by active control or actuation and so on or so on at least substantially prevents the gas mixture can flow through the conduit means against the direction of movement of the bulk material.

The lock mechanism may comprise a rotary valve. Rotary valves are known in the art in a variety of configurations.

Alternatively, the flow of the gas mixture through the conduit opposite to the direction of movement of the bulk material can also be completely or at least substantially prevented by the conduit being designed such that it is closed by a part of the bulk material remaining in the conduit means. For this purpose, the conduit means may be configured as a channel, which has an upper and a lower end when used as intended or intended arrangement, wherein the part of the bulk material closes the lower end. This can be achieved by transporting the bulk material at the lower end through the second spreading, mixing and moving means only in such an amount to the second reaction surface that enough bulk material remains in the conduit means to completely or at least substantially prevent that the gas mixture can flow through the conduit means counter to the direction of movement of the bulk material. The here and the aforementioned channel can each be designed in the form of a tube.

In one embodiment of the method, at least one further reaction surface is present and the bulk material is transferred between the steps b) and c) from the second reaction surface to the further reaction surface or one of the further reaction surfaces and thereon by means of a third propagation, agitation and mixing agent spread, mixed and moved and from above and / or from one side with the oxygen-containing gas mixture so applied that the gas mixture flows over the bulk material, without flowing through the bulk of the bulk material. The pressurization with the oxygen-containing gas mixture and possibly water can be effected here and in all other embodiments of the method according to the invention by providing a surface for blowing in above the second reaction surface and, if present, the further reaction surface or each further reaction surface, which gas outlet openings has on its underside, ie in the direction of the second reaction surface or the further reaction surface or each of the further reaction surfaces. However, the means for acting on the gas mixture containing the oxygen and possibly water can also be designed as a pipe or bar with gas outlet openings in the direction of the respective bulk material be and can be designed so that it is moved to act on the bulk material with the gas mixture over the bulk material, for example in a circular motion.

The transfer to the further reaction surface can be effected by the transfer means, which, in particular by the provision of at least one protective shield, a transfer channel, at least one side bounded by a second protective wall second slide surface or a transfer channel, is designed so that it is the bulk material in passing before protects to be swirled by a flow of the gas mixture. In step b), the bulk material is moved towards the transfer means and optionally into the transfer means and on at least one, in particular traversed by the bulk material, the further reaction surfaces to the discharge and optionally into the discharge. The transfer channel may be formed in the form of a tube.

It is also possible that a plurality of further reaction surfaces is present, with a transfer between the other reaction surfaces in each case by a further transfer means, which, in particular by the provision of at least one further protective shield, a further transfer channel, one bounded at least on one side by a third protective wall Third slip surface or another transfer channel, is designed so that it protects the bulk material when passing from being swirled by a flow of the gas mixture. The bulk material is in each case moved by the third propagation, movement and mixing means in each case towards the further transfer means and optionally into the further transfer means. It is possible that the bulk material is moved only on the last of the bulk material traversed by the other reaction surfaces to the discharge out and optionally into the discharge. The further transfer channel can also be designed in the form of a tube.

It is also possible that at least one cooling surface is present and the bulk material before step c) of the second reaction surface or the other reaction surface or one of the further reaction surfaces is transferred to the cooling surface or one of the cooling surfaces and spread thereon by means of a fourth spreading, mixing and moving agent, mixed and agitated and from above and / or one side with the gas mixture or another gas mixture so applied, that the gas mixture or the further gas mixture flows over the bulk material without flowing through the bulk of the bulk material. In this case, the gas mixture or the further gas mixture has a lower temperature than the bulk material charged therewith, wherein the transfer to the cooling surface and possibly from one of the cooling surfaces to another of the cooling surfaces takes place in each case by an additional further transfer means, which is designed such that it protects the bulk material from being swirled by a flow of the gas mixture or of the further gas mixture when passing it over. In this case, the bulk material at step b) or, if present, on the further reaction surface or on one of the further reaction surfaces instead of the discharge and optionally in the discharge into the additional further transfer means and optionally in the additional further transfer means into, and, if a plurality of cooling surfaces is present, on at least one of the cooling surfaces for additional further transfer means and optionally in the additional further transfer means and / or on at least one, in particular traversed by the bulk last, the cooling surfaces to the discharge out and optionally into the discharge emotional.

In one embodiment of the method according to the invention, the first, second and / or at least one further reaction surface and / or the at least one cooling surface are each independently a plane, a flat round, a flat circular, a planar polygonal or a cylindrical surface. If the first, second and / or the at least one further reaction surface and / or the at least one cooling surface are in each case a plane, a flat round, a flat circular or a planar polygonal surface, the first, second, third and or fourth propagation, mixing and moving means are fixed and the first, second and / or at least one further reaction surface and / or the at least one cooling surface may each be rotatably formed, in particular by arrangement on a common shaft and under normal use or intended arrangement, in each case at least one of the first, second, third and / or fourth propagating, mixing and moving means are rotated through, so that the spread on the surface bulk material is thereby spread, mixed and moved. The spreading, mixing and moving of the bulk material by means of the first, second, third and / or fourth propagation, mixing and moving means does not necessarily mean that the first, second, third and / or fourth propagation, mixing and Moving means must move. It suffices if relative movement takes place between the first, second and / or at least one further reaction surface and / or at least one cooling surface on the one hand and the first, second, third and / or fourth propagation, mixing and moving agent on the other hand.

An associated with the fixed training of the first, second, third and / or fourth propagation, mixing and movement means advantage consists in a lower maintenance effort for it. Another advantage consists in a possibility, the conduit means, transfer means, further transfer means, additional additional transfer means and / or discharge also fixed and in particular only at one point of the circumference of the first, second and / or at least one further reaction surface and / or at least one cooling surface to arrange. The conduit means, transfer means, further transfer means, additional additional transfer means and / or diversion means can thus each be made relatively simple. An externally on each of the first, second and / or at least one further reaction surface and / or at least one cooling surface fixed only at one point arranged conduction means, transfer means, further transfer means, additional further transfer means and / or discharge means allows the gas mixture relatively unhindered on the outside and on the outside respectively at the first, second and / or at least one further reaction surface and / or at least a cooling surface can flow past almost unhindered at almost its entire circumference.

Alternatively, the area, i. H. the first, second and / or at least one further reaction surface and / or the at least one cooling surface, be formed fixed and above each of the surfaces may each have at least a first, second, third and / or fourth propagation, mixing and moving means, in particular by Arrangement of all of the first, second, third and / or fourth propagation, mixing and moving means on a common shaft to be rotatably mounted and rotated in normal use or intended arrangement over each of the surfaces, so that the bulk material on the respective surface thereby spread, mixed and moved.

In the whole process, the bulk material can be spread over all of the existing surfaces, i. H. the first, second and / or at least one further reaction surface and / or at least one cooling surface, in each case alternately moved concentrically from outside to inside and from inside to outside or from inside to outside and from outside to inside.

The discharge means may, in particular by the provision of at least one additional further protective shield, a discharge chute, a discharge chute or discharge channel delimited at least on one side by a fourth protective wall, be designed so as to protect the bulk material from being expelled by a flow of the gas mixture or to be swirled further gas mixture. The discharge can, for example, also a conveyor, such as. B. a screw conveyor include. The diversion channel can be designed in the form of a tube.

In one embodiment of the method, the first reaction surface and the second reaction surface and, if present, the at least one further reaction surface and, if present, the at least one cooling surface arranged together in the reaction space.

In step a), the bulk material can be at least partially heated by a combustion chamber from above, which is at least partially fed with pyrolysis and / or in the partial oxidation resulting gas. This allows the process to enable autothermal pyrolysis of the organic portion of the bulk material. In an autothermal pyrolysis required for carrying out the pyrolysis energy must not be supplied from the outside by a heater, but is caused by partial oxidation of the organic content of the bulk material or the resulting gas. Only to initiate the process and initiate the pyrolysis, it is necessary to supply energy from the outside. Further heating devices, in particular in the walls of the reaction space or the further reaction space are not required.

In a further refinement of the method, the first, second, third and / or fourth propagation, mixing and moving means are / are each independently designed as rakes. The second, third and / or fourth spreading, mixing and moving means can each independently of one another exclusively serve to spread, mix and move the bulk material and thus not to act on the gas mixture containing the oxygen or the further gas mixture. The decoupling of a means for loading with the oxygen-containing gas mixture or the further gas mixture of the second, third and / or fourth propagation, mixing and moving means, the Aufwirbelung dust can be avoided or further reduced.

The process can be carried out such that the temperature to which the bulk material is heated from above in step a) does not exceed 850 ° C., in particular 800 ° C. The pressurization with the oxygen-containing gas mixture can be regulated in dependence on the temperature reached in the oxidation or partial oxidation in the bulk material temperature such that a temperature of 850 ° C, in particular a temperature of 800 ° C, is not exceeded. In the presence of at least one further reaction surface, the reaction with the oxygen-containing gas mixture can be carried out independently for the bulk material on the second and the further reaction surface or for the bulk material on the second and each of the further reaction surfaces, depending on the oxidation or partial oxidation in the Bulk material respectively reached temperature are regulated so that a temperature of 850 ° C, especially 800 ° C is not exceeded.

Previously, a sulfur-containing solid to be burned to desulfurize the resulting combustion gas was often lime, d. H. Calcium carbonate and / or calcium oxide, admixed. However, this was later disregarded, because the resulting gypsum with the resulting dust into the exhaust gas and then fogged the exhaust pipes leading or even added. In the method according to the invention, however, the bulk material can be mixed with powdered lime before or during the implementation of step a) or step b), without causing the problems mentioned, because resulting gypsum by at least largely preventing dust formation not or at least not in substantial quantity into the exhaust gas and thereby not misting the exhaust gas lines or essentially fogging or enforce can.

• einen Reaktor mit einem Reaktionsraum und optional einem weiteren Reaktionsraum,
• eine erste Reaktionsfläche im Reaktionsraum,
• mindestens ein Heizmittel, um das Schüttgut von oben zur Pyrolyse des organischen Anteils des Schüttguts zu erhitzen,
• eine zweite Reaktionsfläche im Reaktionsraum oder einem weiteren Reaktionsraum,
• ein Leitungsmittel, um das Schüttgut in einer Bewegungsrichtung auf dem Leitungsmittel oder durch das Leitungsmittel hindurch auf die zweite Reaktionsfläche überzuleiten,
• ein erstes Ausbreitungs-, Durchmischungs- und Bewegungsmittel zum Ausbreiten, Durchmischen und Bewegen von einer in den Reaktionsraum des Reaktors eingebrachten und auf der ersten Reaktionsfläche aufgebrachten Schüttung des Schüttguts und um das Schüttgut auf der ersten Reaktionsfläche zum Leitungsmittel hin und optional in das Leitungsmittel hinein zu bewegen,
• ein zweites Ausbreitungs-, Durchmischungs- und Bewegungsmittel zum Ausbreiten, Durchmischen und Bewegen des Schüttguts auf der zweiten Reaktionsfläche und um das Schüttgut auf der zweiten Reaktionsfläche zu einem Ausleitmittel, einem optional vorhandenen Überleitungsmittel oder einem optional vorhandenen zusätzlichen weiteren Überleitungsmittel hin und optional in dieses hinein zu bewegen,
• ein Gaseinleitungsmittel, um ein Sauerstoff enthaltendes Gasgemisch in den Reaktionsraum oder den weiteren Reaktionsraum einzuleiten, um das Schüttgut mit dem Sauerstoff enthaltenden Gasgemisch in Kontakt zu bringen,

wobei das Gaseinleitungsmittel so ausgebildet ist, dass das Schüttgut dadurch von oben und/oder von einer Seite her mit dem Gasgemisch so beaufschlagt werden kann, dass das Gasgemisch das Schüttgut überströmt, ohne die Schüttung des Schüttguts zu durchströmen. Das Leitungsmittel ist so ausgebildet, dass dadurch vollständig oder zumindest im Wesentlichen verhindert wird, dass ein Strom des Gasgemischs das sich auf dem oder durch das Leitungsmittel bewegende Schüttgut kreuzen oder durchströmen kann oder dass das Gasgemisch durch das Leitungsmittel entgegen der Bewegungsrichtung des Schüttguts strömen kann.The invention further relates to a device for carrying out the method according to the invention, comprising

• a reactor with a reaction space and optionally a further reaction space,
• a first reaction surface in the reaction space,
• at least one heating means to heat the bulk material from above for pyrolysis of the organic portion of the bulk material,
• a second reaction surface in the reaction space or another reaction space,
• conduit means for passing the bulk material in a direction of travel on the conduit means or through the conduit means to the second reaction area;
• a first spreading, mixing and agitating means for spreading, mixing and agitating a bulk of the bulk material introduced into the reaction space of the reactor and applied to the first reaction surface and around the bulk material on the first reaction surface to the conduit means and optionally into the conduit means move,
• a second spreading, mixing and agitating means for spreading, mixing and moving the bulk material on the second reaction surface and around the bulk material on the second reaction surface to a discharge means, an optional transfer means or an optional additional additional transfer means and optionally into this to move,
• a gas introduction means for introducing an oxygen-containing gas mixture into the reaction space or the further reaction space in order to bring the bulk material into contact with the oxygen-containing gas mixture,

wherein the gas introduction means is designed so that the bulk material can be acted upon from above and / or from one side with the gas mixture so that the gas mixture flows over the bulk material, without flowing through the bulk of the bulk material. The conduit means is adapted to thereby completely or at least substantially prevent a flow of the gas mixture from moving on or through the conduit means Can cross or flow through bulk material or that the gas mixture can flow through the conduit means against the direction of movement of the bulk material.

The at least one heating means may be, for example, a gas burner, which can be operated at the beginning of carrying out the method according to the invention with externally supplied gas and later with the process resulting from the pyrolysis gas and optionally oxidizing gas, which is formed in incomplete oxidation of the bulk material , The heating means also includes an air supply and a combustion gas discharge. It is also possible to provide two independent heating means, namely a first one for initial heating to initiate the pyrolysis and a second one for operation with the gas resulting from the pyrolysis and said oxidizing gas. The first heating means to start the process, z. B. be an electric heater.

The transfer of the bulk material through the conduit means can be effected solely by gravity or by an active conveyor or an active conveying mechanism, for example by means of a screw conveyor.

Fig. 1

zeigt eine schematische Darstellung einer zur Durchführung des erfindungsgemäßen Verfahrens geeigneten erfindungsgemäßen Vorrichtung.

Fig. 2

zeigt eine schematische Darstellung einer zur Durchführung des erfindungsgemäßen Verfahrens geeigneten alternativen erfindungsgemäßen Vorrichtung.

The invention will be explained in more detail with reference to an embodiment.

Fig. 1

shows a schematic representation of a device according to the invention suitable for carrying out the method according to the invention.

Fig. 2

shows a schematic representation of an alternative device according to the invention suitable for carrying out the method according to the invention.

The bulk material 10 is in the embodiment according to Fig. 1 introduced via the feed device 11 by means of the screw conveyor 9 contained in the reaction chamber 12 of the reactor 14 and thereby applied to the first reaction surface 16. There it is spread by means of the rake 28 or distributed and mixed and moved to the conduit means 17 and into the conduit means 17 into it. The conduit 17 is tubular. Bulk material 10 falling into the conduit 17 passes through the conduit means 17 onto the second reaction surface 18 where it is spread by the rake 28, mixed and moved outwardly. While the bulk material 10 is located on the first reaction surface 16 and is mixed by means of the rake 28, it is simultaneously heated from above by means of a heating means, not shown here, to a sufficient temperature for pyrolysis of the organic material contained in the bulk material 10. The oxygen-containing gas mixture 20 required for combustion in the heating medium is supplied from outside. The resulting combustion gas 23 is discharged to the outside.

Bulk material 10 falling into the conduit means 17 reaches the second reaction surface 18 only slowly, so that a sufficient amount of the bulk material 10 remains in the conduit means 17 in order to at least substantially prevent the material being introduced from above onto the bulk material 10 via the gas introduction means 21 the second reaction surface 18 inflated oxygen containing gas mixture 20 and resulting therefrom oxidizing gas flows towards the bulk material 10 in the conduit 17. The scraper 25 provided on the rake 28 above the second reaction surface 18 on the inside serves to push the bulk material 10, which has reached the second reaction surface 18 from the conduit 17, outwards from the area of the charge on the second reaction surface 18, so that it is there spread by the rake 28, mixed and moved outwards to the transfer means 24 out. As soon as it reaches the scraper 25, it is stripped down by the second reaction surface 18 and falls, protected against a gas flow through the protective shield 26 formed, for example, as a protective plate, on the further reaction surface 19. The on the rake 28 on the further reaction surface 19 arranged scraper 25 serves to push the 10 arrived on the further reaction surface 19 bulk material from the area of the inward so that it spread there by means of the rake 28, mixed and moved to the discharge 22 and into the discharge 22 into it becomes. This is done by the bulk material, as soon as it reaches the scraper 25, is stripped down from the further reaction surface 19 and falls into the discharge 22. The diversion means 22 comprises a further conveyor screw 29 in order to remove the bulk material 10.

The first 16, second 18 and further reaction surface 19 are all mounted on the shaft 27. Rotation of the shaft 27 causes rotational movement of the first 16, second 18, and other reaction surfaces 19 relative to the stationary rake 28 to spread, mix, and agglomerate the bulk material 10 on the first reaction surface 16, the second reaction surface 18, and the further reaction surface 19 move. Like the rake 28, the scrapers 25 are fixed.

The bulk material 10 on the second reaction surface 18 and the other reaction surface 19 is so easily blown from above with the oxygen-containing gas mixture 20 from the gas introduction means 21, that on the one hand no Staubaufwirbelung arises, on the other hand, however, by mixing simultaneously enough bulk material 10 with the gas mixture 20 comes into contact to cause sufficient oxidation of the organic portion of the bulk material 10.

In the present embodiment, it is caused by the conduit means 17, the transfer means 24 and the relatively gentle loading of the bulk material 10 with the gas mixture 20 from above that it does not happen that entrained the powdered bulk material or the dust-like portion of the bulk material with the gas mixture 20 and that there is no turbulence or turbulence of the powdery bulk material or the dust-like portion of the bulk material. As a result, a dust load of the combustion gas 23 is avoided. At the same time a very uniform oxidation of the organic content of the bulk material 10 is achieved by mixing the bulk material 10 when exposed to the gas mixture.

In the Fig. 2 illustrated device of the invention differs from the in Fig. 1 illustrated apparatus only in that the transfer means 24 instead of the protective shield 26 includes a second sliding wall 32 equipped with a second sliding surface 32. The designation as a "second" protective wall 30 or "second" sliding surface 32 takes place only to distinguish from a non-existing first slide surface and a first protective wall, which can form the conduit 17 for the transfer from the first reaction surface 16 to the second reaction surface 18. The transfer means 24 also comprises the scraper 25, which strips off the bulk material 10 from the second reaction surface 18, so that the bulk material 10 thereby reaches the second slip surface 32 and is directed onto the further reaction surface 19. The scraper 25 arranged on the rake 28 above the further reaction surface 19 serves to push the bulk material 10, which has reached the further reaction surface 19 from the second sliding surface 32, inwards from the area of the outflow from the second sliding surface 32, so that it is there by means of of the rake 28 is spread, mixed and moved to the discharge 22 toward. The scrapers 25, the rake 28 and the second sliding surface 32 with the protective wall 30 are each designed to be stationary, while the first 16, second 18 and further reaction surface 19 rotate under the respective rake 28. The other sequence of the method corresponds to that for the embodiment according to Fig. 1 shown procedure.

LIST OF REFERENCE NUMBERS

9

Auger

10

bulk

11

feeder

12

reaction chamber

14

reactor

16

first reaction surface

17

conduit means

18

second reaction surface

19

further reaction surface

20

mixture of gases

21

Gas introduction means

22

Ausleitmittel

23

combustion gas

24

Reconciliation means

25

scraper

26

shield

27

wave

28

rake

29

further screw conveyor

30

second protective wall

32

second sliding surface

Claims (15)

Process for the at least partial pyrolysis and at least partial oxidation of an organic fraction of a dusty or dusty bulk material (10) of at least partially organic origin, comprising the following steps: a) introduction of a bed of bulk material (10) into a reaction space (12) of a reactor (14), wherein the bulk material (10) is applied to a first reaction area (16) in the reaction space (12) and by means of a first spreading, mixing and moving means spread, mixed and moved to a conduit means (17) and optionally into the conduit means (17) and thereby heated from the top to a temperature at which it is to complete or partial pyrolysis of the organic portion of the bulk material (10) comes, wherein the bulk material (10) is transferred in a direction of movement on or through the conduit means (17) on a second reaction surface (18) in the reaction space (12) or another reaction space, b) spreading, mixing and moving the bulk material (10) on the second reaction surface (18) by means of a second spreading, mixing and moving means, wherein the bulk material (10) to a discharge means (22) or transfer means (24) out and optionally into the discharge means (22) or transfer means (24) is moved, wherein the bulk material (10) with an oxygen-containing gas mixture (20) is brought into contact, so that there is at least partial oxidation of the organic portion of the bulk material (10) . c) applying the resulting at least partially oxidized bulk material (10) from the reaction space (12) or the further reaction space, through the discharge means (22), characterized in that the bulk material (10) is brought into contact with the gas mixture (20) in that it is acted upon from above and / or from one side with the gas mixture (20) so that the gas mixture (20) the bulk material (10) flows through, without flowing through the bulk of the bulk material (10), wherein the gas mixture (20) optionally contains water in the form of vapor or an aerosol, or wherein the bulk material (10) except with the gas mixture (20) in contact with water wherein a gas outlet opening is arranged in the reaction space above the first reaction surface (16), wherein completely or at least substantially prevents a flow of the gas mixture (20) the bulk material (10) moving on or through the conduit means (17) ) or flows through or that the gas mixture (20) flows through the conduit means (17) counter to the direction of movement of the bulk material (10). A method according to claim 1, characterized in that thereby completely or at least substantially prevents a stream of the gas mixture (20) crosses or flows through the bulk material (10) moving on or through the conduit means (17), that the conduit means ( 17) is formed at least partially in the form of a channel or a first sliding surface bounded at least on one side by a first protective wall,
or
that thereby completely or at least essentially prevents the gas mixture (20) from flowing through the conduit means (17) counter to the direction of movement of the bulk material (10),
the conduit means (17) has a closing mechanism or lock mechanism which is passable in the direction of movement of the bulk material (10) and which is not or substantially non-passable for the gas mixture (20) counter to the direction of movement,
or
in that the conduit means (17) is designed such that it is closed by a part of the bulk material (10) remaining in the conduit means (17). A method according to claim 2, characterized in that the closing mechanism comprises a flap which opens under a weight of the bulk material (10) or is opened by active control or actuation to allow the bulk material (10) to pass therethrough closes or is closed by active control or actuation,
and or
the lock mechanism comprises a rotary valve
and or
in that the conduit means (17) is thereby designed such that it is closed by the part of the bulk material (10) remaining in the conduit means (17) such that the conduit means (17) is designed as a channel which, when used as intended, has an upper end and a lower end, wherein the part of the bulk material (10) closes the lower end, wherein the bulk material (10) at the lower end by the second propagation, mixing and moving means only in such an amount on the second reaction surface (18) is removed in that enough bulk material (10) remains in the conduit means (17) in order to completely or at least substantially prevent the gas mixture (20) from flowing through the conduit means (17) counter to the direction of movement of the bulk material (10). Method according to one of the preceding claims, characterized in that at least one further reaction surface (19) is present and the bulk material (10) between the steps b) and c) of the second reaction surface (18) on the further reaction surface (19) or a the other reaction surfaces (19) is transferred and spread thereon by means of a third spreading, mixing and moving agent, mixed and agitated and from above and / or from one side with the oxygen-containing gas mixture (20) is acted upon so that the gas mixture (20) the bulk material (10) flows through, without flowing through the bulk of the bulk material (10), wherein the passing on the further reaction surface (19) by the transfer means (24), which, in particular by the provision of at least one protective shield (26), a Transition channel, a second slide surface (32) or a transfer channel delimited at least on one side by a second protective wall (30) is designed such that it protects the bulk material (10) from being swirled by a flow of the gas mixture (20) when passing wherein the bulk material (10) in step b) to the transfer means (24) and optionally into the transfer means (24) into and on mindes at least one, in particular of the bulk material last passed, the further reaction surfaces (19) to the discharge (22) and optionally in the discharge (22) is moved into it. A method according to claim 4, characterized in that a plurality of further reaction surfaces is present, wherein a transfer between the other reaction surfaces in each case by a further transfer means, which, in particular by the provision of at least one further protective shield, a further transfer channel, one at least on one side by a third protective wall limited third sliding surface or another transfer channel, is designed so that it protects the bulk material (10) when passing from being swirled by a flow of the gas mixture (20), wherein the bulk material (10) each to further transfer means and is optionally moved into the further transfer means into it. Method according to one of the preceding claims, characterized in that at least one cooling surface is present and the bulk material (10) before step c) transferred from the second reaction surface (18) or the further reaction surface or one of the further reaction surfaces on the cooling surface or one of the cooling surfaces and then by means of a fourth propagation, Spreading and moving agent spread, mixed and moved and from above and / or one side with the gas mixture (20) or another gas mixture is applied so that the gas mixture (20) or the further gas mixture, the bulk material (10) flows over, without the bulk of the bulk material (10) to flow through, wherein the gas mixture (20) or the further gas mixture has a lower temperature than the bulk material (10) thus acted, wherein the passing on the cooling surface and possibly from one of the cooling surfaces to another of the Cooling surfaces in each case by an additional further transfer means is carried out, which is designed so that it protects the bulk material (10) against being swirled by a flow of the gas mixture (20) or the further gas mixture, wherein the bulk material (10) at step b) or, if present, on the further reaction surface (19) or on one of the further reaction surfaces sta tt to the discharge means (22) and optionally into the discharge means (22) into the additional further transfer means and optionally into the additional further transfer means, and, if a plurality of cooling surfaces are present, on at least one of the cooling surfaces to the additional further transfer means and optionally in the additional further transfer means into and / or on at least one, in particular of the bulk material last traversed, the cooling surfaces to the discharge (22) and optionally in the discharge (22) is moved into. Method according to one of the preceding claims, characterized in that the first (16), second (18) and / or the at least one further reaction surface (19) and / or the at least one cooling surface each independently a flat, a flat round, a plane is circular, a plane polygonal or a cylindrical surface. The method of claim 7, wherein the first (16), second (18) and / or the at least one further reaction surface (19) and / or the at least one cooling surface each have a flat, a flat round, a flat circular or a planar polygonal surface is, characterized in that
the first, second, third and / or fourth propagation, mixing and movement means are stationary and the first (16), second (18) and / or at least one further reaction surface (19) and / or the at least one cooling surface respectively, In particular, by arrangement on a common shaft (27), is rotatable and is rotated under normal use, in each case at least one of the first, second, third and / or fourth propagation, mixing and moving means therethrough, so that spread on the surface Bulk material (10) is spread, mixed and moved thereby,
or
the surface is stationary and over each of the surfaces at least a first, second, third and / or fourth propagating, mixing and moving means, in particular by arranging all of the first, second, third and / or fourth propagation, mixing and Moving means on a common shaft (27), is rotatably arranged and is rotated in normal use over each of the surfaces, so that the bulk material (10) on the respective surface thereby spread, mixed and moved. Method according to one of the preceding claims, characterized in that the diverting means (22), in particular by the provision of at least one additional further protective shield, a discharge chute, a discharge chute formed on at least one side by a fourth protective wall, or a diverting duct, is designed such that it Bulk material (10) during application protects against being swirled by a flow of the gas mixture (20) or of the further gas mixture. Method according to one of the preceding claims, characterized in that the first reaction surface (16) and the second reaction surface (18) and, if present, the at least one further reaction surface (19) and, if present, the at least one cooling surface are arranged together in the reaction space (12). Method according to one of the preceding claims, characterized in that the bulk material (10) in step a) is at least partially heated by a combustion chamber from above, which is at least partially fed with pyrolysis and / or in the partial oxidation resulting gas. Method according to one of the preceding claims, characterized in that the first, second, third and / or fourth propagation, mixing and moving means are each independently of one another as rake (28) is / are formed and / or the second, third and / or Fourth spreading, mixing and moving means each independently of each other exclusively the spreading, mixing and moving of the bulk material (10) and thus not the admission of oxygen-containing gas mixture (20) or the further gas mixture is used. Method according to one of the preceding claims, characterized in that the temperature to which the bulk material (10) is heated in step a) from above, 850 ° C, in particular 800 ° C, does not exceed and / or the impingement with the oxygen-containing Gas mixture (20), in particular in the presence of at least one further reaction surface (19) each independently for the bulk material (10) on the second reaction surface (18) and the further reaction surface (19) or for the bulk material (10) on the second reaction surface (18 ) and each of the further reaction surfaces (19), depending on the in the oxidation or partial oxidation in the bulk material (10), in particular respectively, reached temperature is controlled so that in this case a temperature of 850 ° C, in particular a temperature of 800 ° C, is not exceeded. Method according to one of the preceding claims, characterized in that the bulk material (10) before or during the implementation of step a) or step b) is mixed with powdered lime. Apparatus for carrying out a method according to one of the preceding claims, comprising a reactor (14) having a reaction space (12) and optionally a further reaction space, a first reaction surface (16) in the reaction space (12), at least one heating means for heating the bulk material (10) from above for pyrolysis of the organic portion of the bulk material (10), a second reaction surface (18) in the reaction space (12) or another reaction space, - a conduit means (17) for transferring the bulk material (10) in a direction of movement on the conduit means (17) or through the conduit means (17) to the second reaction surface (18), a first spreading, mixing and moving means for spreading, mixing and moving of a bulk material (10) introduced into the reaction chamber (12) of the reactor (14) and applied to the first reaction surface (16) and around the bulk material ( 10) on the first reaction surface (16) towards the conduit means (17) and optionally into the conduit means (17), a second spreading, mixing and moving means for spreading, mixing and moving the bulk material (10) on the second reaction surface (18) and around the bulk material (10) on the second reaction surface (16) to a discharge means (22) Optionally available transfer means (24) or an optionally available additional further transfer means and optionally to move into this, a gas introduction means (21) for introducing an oxygen-containing gas mixture (20) into the reaction space (12) or the further reaction space in order to bring the bulk material (10) into contact with the oxygen-containing gas mixture (20), characterized in that the gas introduction means (21) is formed so that the bulk material (10) can be acted upon from above and / or from one side with the gas mixture (20) so that the gas mixture (20) the bulk material (10 ) flows through, without flowing through the bulk of the bulk material (10), wherein the conduit means (17) is formed so that thereby completely or at least substantially prevents a stream of the gas mixture (20) located on or through the conduit means (17) can cross or flow through moving bulk material (10) or that the gas mixture (20) can flow through the conduit means (17) counter to the direction of movement of the bulk material (10).

Images