EP1323809A2 - Co-current shaft reactor - Google Patents

Abstract

Direct flow shaft reactor comprises a vertical shaft body (10) for drying, heating and gasifying the material to be treated and having a feed opening (28) for introducing the material; a receiving body (20); a gas removing device (26) connected to the shaft body and/or the receiving body; and a gas feeding device (36) connected to the shaft body for introducing gas to the shaft and for drying the material. <??>Direct flow shaft reactor comprises a vertical shaft body (10) for drying, heating and gasifying the material to be treated and having a feed opening (28) for introducing the material; a receiving body (20) connected to the shaft body for receiving melted material; a gas removing device (26) connected to the shaft body and/or the receiving body; and a gas feeding device (36) connected to the shaft body for introducing gas to the shaft and for drying the material. Preferred Features: The gas feeding device and the gas removing device are connected together via a heat exchanger (56). The gas feeding device is connected to a heater (64). A sluice arrangement (12) is connected to the feed opening and has a sluice chamber. The gas feeding device is connected to the sluice chamber.

Description

The present invention relates to a DC shaft reactor for Melting and gasifying feedstocks of different types and Consistency, such as pollutant-free and / or contaminated woods, house and Bulky waste, alternative fuels, pelletized dusts or animal meal, Plastics, industrial and commercial waste.

In shaft reactors, a synthesis gas, which is used to generate electrical energy and heat is suitable and / or as a basis for Synthesis processes are used. As a solid product creates a non-leachable slag and a materially processable Metal phase or a non-elutable liquid phase, which for a further processing is available.

DE 43 17 145 C1 describes a method and a device for degassing of waste materials based on a coke-heated counterflow shaft furnace. The resulting dust-containing gas is completely drawn off and in the melting and superheating zone underneath with oxygen burned at high temperatures. The countercurrent flow of the gas through the moving bed and the suction between the Circulation gas extraction and the circulation gas supply result in a large number of practical problems. The result is short-circuit currents in the shaft and inadequate heat transfer to the upper shaft area, causing a polluted gas with tar and dust components is produced. hereby complex gas treatment and purification becomes necessary. Further there is a risk that the tar and dust deposits continuous operation is disrupted. Another permanent danger to you stable operation is the management of pyrolysis and degassing gas with tar Dust in lines. Partial or full transfer of the Lines with tar dust deposits have an uneven Recycle gas flow and thus an uneven process control in the Shaft furnace resulted.

In DE 196 40 497 C2 a coke-heated cycle gas cupola is used material and / or energy recovery of waste materials described. It consists of a vertical furnace shaft with below the Facing large volume recycle gas vents through Channels and nozzles are connected to the melting and overheating zone, above which a large volume excess gas extraction level resulting gas from the process. Here is the furnace shaft part between recycle gas and excess gas suction opening querschnittsverjüngt. The heat transfer takes place as in DE 43 17 145 C1 due to the fact that the feedstock rises upwards in the countercurrent principle Process gases. The multiple countercurrent flow of the gas through the moving bed allows despite some modifications by narrowing the cross-section in the shaft and expanding the cross-section in the Gas discharge does not mean processing a wide range of feed.

Furthermore, DE 198 16 864 A1 describes a cycle gas cupola, in which an excess gas extraction below the melting and Overheating zone is arranged. This results in a Counterflow gasification and heat transfer in the upper furnace shaft area, where the gas is sucked off through large-volume openings and through Channels / nozzles are directed into the melting and overheating zone. In the Subsequent DC gasification turns the gas at high temperatures reduced and longer-chain hydrocarbons split. Through this The chosen arrangement is the negative influence of short-circuit currents reduced. The spatial proximity of the endothermic processes to the range and the large-volume excess gas extraction removes from the melt necessary heat to the necessary under all operating conditions to ensure liquid discharge of the melt.

DE 100 07 115 A1 describes a reactor for gasifying and / or melting Feedstocks with a feed, pyrolysis, melting and Overheating section described. The pyrolysis section has one Cross-sectional expansion as a gas supply space in which at least one Combustion chamber with at least one burner, through which hot Combustion gases are fed to a bulk cone that forms. Furthermore, high-energy media are created using upper and lower Injection agents in the area of the melting and overheating zone as well introduced above the melt by means of oxygen lances and / or nozzles. The disadvantage of this device is that it is enlarged by the cone Reactor surface in the area of the cross-sectional expansion of the pyrolysis, because Heat losses occur. Furthermore, the larger ones roll at the cone Pieces of the feed materials on the reactor wall, creating an adverse Segregation occurs. The result is a strongly one-sided melting of the Furnace lining, which leads to a shorter service life of the reactor. By the segregation forms preferred flow channels in the bed for the entering gases. This has the consequence that different form inhomogeneous reaction zones, the fluctuating gas qualities to lead.

In general, it can be assumed that materials with high Ignition points with poor heat conduction and with substances with high humidity the heat supplied in the pyrolysis section is not sufficient Heating and pyrolysis or degassing of the substances leads. The processes of Degassing and gasification shift into the area of melting and Overheating section and thus reduce the reaction time to destruction all tars and oils that form in the form of longer-chain hydrocarbons.

All of the shaft reactors described above are only for one small range of feed materials can be used. Furthermore, to gasify the Feedstocks are fed a significant amount of energy. this happens through different nozzle systems in the vertical shaft bodies are arranged, as well as together with the bulk material in the Shaft body introduced fuel, such as coke or the like. Furthermore, known shaft reactors exist regardless of whether they are in the Co-current or counter-current principle work, the problem that that withdrawn gas is heavily contaminated with particles and thus in front of a Further processing, for example, must be filtered.

The object of the invention is a DC shaft reactor to create with that even when using different input materials Commercial gases, especially flammable commercial gases with a low Particle pollution can be generated, the energy content for the DC shaft reactor can be used.

The object is achieved according to the invention by the features of Claim 1.

The inventive DC shaft reactor for melting and Gasification of feedstock has a vertical shaft body. The feed material is dried and heated within the shaft body and gasified. The shaft body can therefore usually be divided into the areas Divide the drying zone, degassing zone and gasification zone. To the The shaft body is followed by a receiving body, which is used to hold molten feed. Within that body is the Melting zone of the reactor formed. The shaft body and / or the Receiving bodies are equipped with a gas discharge device for removing the Produced useful gases generated within the reactor. In particular, the Discharge device in the area between the shaft body and the Arranged body and designed as a tube. Furthermore, the vertically aligned shaft body on a feed device through which the Feed material is fed to the shaft reactor.

According to the invention, a gas supply device for the Supply of gas connected to the manhole body. The gas supplied, at which is preferably air or oxygen-enriched air acts to dry the feed. To be good and effective To achieve drying of the feed is the gas supplied preheated according to the invention. To preheat the gas According to the invention, the gas supply device with the gas discharge device connected. The hot gas discharged from the reactor is according to the invention thus used to preheat the gas supplied to the shaft body. A lock arrangement is arranged downstream of the feed opening of the reactor, that controls the feeding of the feed. In the field of Lock arrangement is at least part of the gas supply device with the Lock chamber connected. The use of the invention dissipated gas as an energy source leads to the preheating of the Gases no additional energy is required and the feed already undergoes a first drying in the lock arrangement. The Lock arrangement is thereby in addition to drying the Input material used. Another significant advantage of the invention is that heat is extracted from the gas that is removed. This is the further processing or use of this gas is simplified.

Due to the preheating of the feed, which is already according to the invention immediately after feeding the feed into the Lock arrangement takes place, can offer a larger product range Feed material can be processed in the shaft reactor, because the Feed material stronger during his stay in the shaft reactor is heated and thus also with poorly processable materials Degassing and gasification can be achieved. In particular, this also means achieved that better degassing and gasification within the reactor takes place so that the useful gas has fewer particles. In particular it is due to the inventive design of the DC shaft reactor possible to produce useful gases that have a significantly lower oil and Tar content and a significantly lower pollutant content.

The feed material is introduced into the shaft body via the Lock arrangement. With the help of the lock arrangement can be ensured that, for example, only a limited amount of ambient air in the shaft reactor passes through the feed opening. This allows the Process can be better controlled within the shaft reactor. The Lock arrangement preferably has at least one lock chamber on. A first lock gate is thus opened in order to insert the feed material in bring in the lock chamber. Then this first lock gate closed so that the lock chamber is closed. In this Condition may contain any air contained in the lock chamber and / or be replaced by another gas. Then the second Lock gate leading towards the interior of the shaft reactor, opened and the feed material comes from the lock chamber into the Reactor.

The lock arrangement is advantageously designed such that the Introducing feed material into the DC shaft reactor almost free cone or low cone. This eliminates the danger reduces that larger pieces of the feed materials roll onto the reactor wall and segregation of the feed takes place. The adverse consequences segregation, such as melting of the furnace lining, Creation of flow channels for the entering gases and fluctuating gas qualities due to different reaction zones thereby greatly reduced. A low-cone introduction of material into Shaft reactors can be achieved, for example, by the fact that the Reactor shaft, which follows the lock arrangement, a similar one Has cross-sectional geometry. Furthermore, the drop height of the fed Good things should be as low as possible. In particular, not higher than three times the height of the feed material in the lock arrangement. In addition, that should open the second lock gate as quickly as possible so that the underside of the falling feedstock remains as horizontal as possible.

Furthermore, the feed material in the lock arrangement should not be possible itself already contain a cone. This can be done, for example thereby achieve that the lock chamber in the lock arrangement completely filled with feed and with the closing of the first Lock gates the material that does not fit in the lock chamber, is cut off from the feed material to be introduced. This is in advantageously the first lock gate as a slide with a cutting edge educated. As a result, the feed material to be introduced almost corresponds the geometry of the lock chamber and in particular has almost none Cone on.

It is so that the second lock gate can be opened as quickly as possible advantageously carried out as a flap or slide.

Figur 1

zeigt eine schematische Seitenansicht eines Gleichstrom-Schacht-Reaktors.

Figur 2

zeigt eine schematische Seitenansicht einer bevorzugten Ausgestaltung einer Schleusenanordnung.

The invention is explained below using a preferred embodiment with reference to the accompanying drawing.

Figure 1

shows a schematic side view of a DC shaft reactor.

Figure 2

shows a schematic side view of a preferred embodiment of a lock arrangement.

The DC shaft reactor has a shaft body 10. The In the exemplary embodiment shown, the shaft body 10 can be converted into a Lock arrangement 12, one adjoining the lock arrangement 12 subsequent drying zone 14, one adjoining the drying zone 14 subsequent degassing zone 16 and a subsequent one Gasification zone 18 can be divided. To the gasification zone 18 of the The shaft body 10 is followed by a receiving body 20, which is used for receiving of molten feed 22 is used. In the border area between the Gasification zone 18 and the receiving body 20 is the cross section of the Receiving body expanded so that a ring-shaped Gas collection chamber 24 is formed, the lower part of the gasification zone 18 surrounds. The gas collecting space 24 is shown in FIG Embodiment designed as a tube gas discharge device 26th connected.

The feed material is fed into the shaft body 10 through a feed opening 28 introduced over the lock assembly 12. Feeding the Feed material takes place via the lock arrangement 12 for introduction large amounts of ambient air, through which the melting and Gasification process can be influenced in an uncontrolled manner to prevent. For this purpose, the lock arrangement 12 has two lock devices or Lock gates 30, 32 between which the lock chamber 34 is formed, the lock chamber 34 already a part of the Manhole body 10 is.

In the illustrated embodiment, the drying zone 14 of the A gas supply device 36 is provided in the shaft body 10. The gas supply device 36 has a ring line surrounding the shaft body 10 38, which have a plurality of nozzles 40 distributed evenly around the circumference connected is. About the gas feed device 36 is the feed in Area of the drying zone 14 preferably hot air, possibly with oxygen can be enriched, fed to dry the feed.

In the degassing zone 16 adjoining the drying zone 14 there is a arranged further gas supply device 42, which is also a Has shaft body 10 surrounding ring line 44. The ring line 44 is with several nozzles 46, which are preferably evenly distributed over the circumference connected. Energy-rich gases, Oxygen, air or other to control the melting and Gases suitable gases are fed to the feed.

Further nozzles 48 are provided in the gasification zone 18. Over the nozzles 48, in turn, high energy gas or other can melt and Gases or substances controlling the gasification process can be supplied. As well instead of the nozzles 48, burners can also be provided which are located in the Gasification zone 18 immediately supply heat to the feed. The End region of the shaft body 10 which is rotationally symmetrical with respect to the longitudinal axis 50 is slightly tapered, so that the feed material in the Area of the gasification zone 18 is somewhat retained.

In a side wall 52 of the receiving body 20 there are also a plurality of Circumferentially distributed nozzles 54 are arranged. The nozzles 54 are used for insertion energy-rich gases or similar substances. Through the nozzles 54 is ensures that the melt 22 remains liquid. Likewise, instead of Nozzles 54 may also be provided to burners.

The gas supply device 36 is connected to the gas discharge device 26. For this purpose, the pipe of the gas discharge device 26 leads through the hot ones in gases produced in the reactor are discharged to a heat exchanger 56. The discharged gases or useful gases flow through the heat exchanger 56 and are then preferably from a tube 58 to Further processing carried away. Furthermore, with the heat exchanger 56 Pipeline 60 connected. Air or another is passed through the pipeline 60 Gas passed into the heat exchanger 56 takes in the heat exchanger 56 Heat from the useful gas and is returned from the pipe 62 Heat exchanger derived. The tube 62 is then over a heater 64 and a pipe 66 with the ring line 38 of the gas supply device 36 connected. Heating the area by the gas supply 36 the drying zone 14 gas supplied to the feedstock is thus in operation preferably exclusively by the heat of the useful gases with the help of Heat exchanger 56 preheated. With the help of the heater 64, where it are, for example, an electric heater or a burner can, the gas to be supplied via the gas supply device can additionally be warmed. Especially during the start cycle of the reactor, in no hot useful gases through the gas discharge device 26 be dissipated or the temperature of these groove gases is not yet high enough the heater 64 can be used to heat the gas.

According to the invention, part 35 of the Gas supply device 36 connected to the shaft body 10. Through this The feedstock is already connected in the lock arrangement 12 subjected to the first drying.

A side wall 68 of the lock arrangement 12 is preferably double-walled. This can cause heating and thus Drying of the feed material can be achieved in the lock chamber 34 by passing a hot medium through the double-walled side wall 68 becomes. It is preferably air or another gas that also by the useful gas, preferably with the help of the heat exchanger 56 is preheated.

The ideal material input preferably uses a homogeneous mixture ahead, especially when adding additives such as coke and lime. The According to the invention, entry takes place centrally on the axis of the reactor. The The reactor should be kept as full as possible during operation. A Level monitoring is therefore preferably directly below the Lock gate 32 attached. Filling takes place at a high cycle rate. Through these measures, the false air entry is simultaneously reduced and improved pressure maintenance in the overall system.

According to the invention, the areas are lock arrangement 12, drying zone 14 and degassing zone 16 into the gasification zone 18 preferably cylindrical or slightly tapered downwards. The The transition between the zones takes place without step-like or abrupt Cross-sectional expansion, i.e. the transition is the same cross section and without the formation of voids, steps or edges that are free of fill layers.

The drying zone 14 can also be used, particularly in the case of larger designs be double-walled. This enables indirect heating of the Good column inside or ensuring an even temperature of the wall and a reduction in condensation on the Inside. Hot air is preferably also used as the heat transfer medium used. The use of the flue gas at the end of the process is also possible.

When the starting material is heated, the drying zone 14 takes place Evaporation of the water takes place. The temperature in the goods rises only slightly above 100 ° C. As the temperature increases, as the process progresses adsorbed gases such as nitrogen and carbon dioxide are released, which are not have arisen from fission reactions. At the latest here from the Degassing can be spoken. The temperature then sets above 250 to 300 ° C Development of gases and vapors that are distilled off low molecular weight compounds and the first fission products. Another one Rising temperature causes the reactions that lead to formation of methane and hydrogen.

The degassing zone 16 can also continue the drying zone 14 be double-walled.

The result is in the lower third of the drying and degassing zone 14, 16 Area in which the internal reactor temperature is greater than that Hot air temperature is. Here, the double-walled version can be replaced by a silicate brickwork to be replaced. An execution of the whole Drying and degassing zone 14, 16 with a ramming mass, also at a double-walled design is advantageous. Less wear and tear on the Steel structural shells stand for lower heat transfer and lower Resistance to temperature changes.

If the bulk column is heated further from approx. 700 ° C, in addition to the Splitting of fuel under the influence of heat is heterogeneous Reaction between the fuel and the unreacted oxygen the air.

The gasification zone 18 is the main reaction zone within the Shaft reactor. This takes place at temperatures of 1,200 to 1,400 ° C Material and energetic implementation of the solids. From the solid Gases and solid products from coke to ash are produced as fuel. For the Complete and even response is critical to having a homogeneous Filling with the degassing gas already created and this gasification agent to be introduced is evenly flowed through. The Gasification zone 18 must be of sufficient height for these reasons have. This is achieved in that the gasification zone 18 as a straight cylindrical area with a transition to a conical reduction of the cross section or immediately as an increasing taper. There themselves through the material implementations and related destructive forces reduce the grain of material, the increase Cavities inside the pillar. By reducing the Shaft cross-section in this area, the rate of descent Material column are equalized, flow channels are destroyed and the formation of larger voids in the bed is avoided.

In continuation of the degassing zone 16 located above, the area of Gasification also lined with a silicate mass.

The lower cylindrical or tapered area of the Gasification area 18 protrudes into the melting zone 20. On this part the column above it lies at least partially, at the same time the temperatures are high there. For securing the mechanical Strength and protection against excessive temperatures are cooled using indirect water cooling in shaft wall 70.

The gas flowed through the zone of the feedstock in cocurrent High temperature gasification 18. The from the expired degassing and Thermolysis reactions are longer chain hydrocarbons have been thermally split here and were at the same time running out Gasification processes involved. A medium combustible gas is formed Calorific value with the main components carbon monoxide, carbon dioxide, Hydrogen and water vapor without components of condensable Hydrocarbons. Many of the chemical reactions that took place are endothermic. The temperature of the gas and the bed is reduced Consequently.

Experienced below the water-cooled area of the gasification area 18 the gas is deflected by about 180 ° and reaches the free bed Room 24. Due to the endothermic processes described above, the Gas a temperature of approximately 1,000 ° C. After a certain calming of the gas and equalization, the gas is sucked out of the reactor above.

The gas collecting space 24 is already part of the melting zone 20, which the top is much wider than the protruding gasification zone 18. The cylindrical melting zone 20 shrinks conically downwards and closes with the base plate, above which the melted phase collects.

The melting zone 20 is in its entirety with a multilayer Provide ramming compound or equipped with a lining. reason the high temperatures required for this. Only in the area of The gas collecting space may not need bricking.

The completely degassed and coked solid is already in places sintered or melted and sinks from the gasification zone 18 into the Melting zone 20.

A level with several oxygen nozzles is integrated into the melting zone 20 or injectors and / or oxidizing burners 54, which also are symmetrically distributed on the axis.

The supply of gas with a high proportion of oxygen leads to this strong exothermic reactions with the gas and the solid from the Gasification zone 18. There are temperatures which are significantly above the The melting point of the material is usually about 1400 ° C to 1600 ° C. in the In the area of the oxygen nozzles there are even hot temperature zones from 1800 to 2000 ° C. Under these conditions and by adding Slag formers and / or materials that lower the melting point, all inorganic pollutants are melted safely.

The melted material collects as a melt at the bottom of the Reactor. This liquid melt is emptied as in the foundry usual via a tap hole and a gutter 72. A type with forehearth or Siphon is possible.

With a sufficiently large design and corresponding residence time of the melt the melt will turn into a heavy metal phase and one on top of it separate floating slag. There is a possibility here about different levels of drainage, a usable metallic phase and a To be able to win slag. There are no organic slags in the product Contain substances and the inorganic components are in a silicate Matrix installed stably. Use as material for port, landfill and Road construction is known, and the production of special ones is also possible Molds and products that are common in the glass industry.

A preferred embodiment of the lock arrangement 12 consists in that the second lock gate 32 is designed as a quick-opening slide (Fig. 2). For this purpose, the lock gate 32 is in particular made of several pieces. When the lock gate 32 is opened, this falls into the lock chamber 34 located feed material evenly in the drying zone 14 of the Shaft body 10. Previously, the feed material with the Lock chamber 34 connected part 35 of the gas supply device 36 pre-dried. In the event that the shaft body 10 with so much Feed material is filled that part of the feed material into the Protrudes lock chamber 34, is the second designed as a slide Lock gate 32 is advantageously provided with a cutting edge. As a result, when the second lock gate 32 is closed, Lock chamber 34 projecting part of the feed are cut off, whereby the lock chamber 34 can be closed again.

So that almost no cone of bulk forms in the lock chamber 34, the lock chamber 34 is completely filled and the part of the Insert that does not fit, cut off. The first is Lock gate 30 executed as a slide with a cutting edge, the separates the upper part of the feed material from the lock chamber 34. The In this embodiment, the first lock gate 30 can also be in several pieces be carried out.

The second is for introducing feed material into the shaft body 10 Lock gate 32 initially closed and the first lock gate 30 opened. As a result, feed material gets into the lock chamber 34 Closing the first lock gate 30 becomes the second lock gate 32 opened, whereby the feed material falls into the shaft body 10. At the same time, additional feed material can already pass through the feed opening 28 be filled, which is provided on the first lock gate 30. Then the filling cycle begins again.

Claims (12)

DC shaft reactor for melting and gasifying feed, with a vertical shaft body (10) for drying, heating and gasifying the feed material, the shaft body (10) having a feed opening (28) for feeding the feed material, a receiving body (20) adjoining the shaft body (10) for receiving molten feed material (22), a gas discharge device (26) connected to the shaft body (10) and / or the receptacle body (20) for removing gases that have formed, a gas supply device (36) connected to the shaft body (10) for supplying gas into the shaft body (10) for drying the feed material, the gas supply device (36) for gas heating being connected to the gas discharge device (26) and a lock arrangement (12) which is arranged downstream of the feed opening (28), characterized in that in the region of the lock arrangement (12) at least part (35) of the gas supply device (36) and / or at least part of the gas discharge device ( 26) is connected to the shaft body (10). DC shaft reactor according to claim 1, characterized in that the gas supply device (36) and the gas discharge device (26) are connected to one another via a heat exchanger (56). DC shaft reactor according to claim 1 or 2, characterized in that the gas supply device (36) is connected to a heating device (64). DC shaft reactor according to one of claims 1-3, characterized in that the lock arrangement (12) has at least one lock chamber (34). DC shaft reactor according to claim 4, characterized in that the gas supply device (36) is connected to the lock chamber (34). DC shaft reactor according to one of claims 1-5, characterized in that the lock arrangement (12) is arranged substantially axially symmetrical to the shaft body (10). DC shaft reactor according to one of Claims 1-6, characterized in that a side wall (68) of the shaft body (10) is double-walled, in particular in the region of the lock arrangement (12), for heating the feed material. DC shaft reactor according to claim 7, characterized in that the double-walled side wall (68) is connected to the gas supply device (36). DC shaft reactor according to one of claims 1-8, characterized in that the cross-sectional area of the shaft body (10) in the region of the drying zone (14) is similar to the cross-sectional area of the lock arrangement (12). DC shaft reactor according to one of claims 1-9, characterized by a first lock gate (30), which is designed in particular as a slide provided with a cutting edge, and / or a quick-opening second lock gate (32), in particular as a Cutting edge provided slider is designed. DC shaft reactor according to claim 10, characterized in that the first lock gate (30) and / or the second lock gate (32) is designed in several pieces. DC shaft reactor according to one of claims 1-11, characterized in that the drop height of the feed material introduced via the lock arrangement (12) is not higher than three times the height of the lock chamber (34).

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