DE10224018B4 - Apparatus and method for generating energy from bioenergy sources and other organic substances - Google Patents

Abstract

Apparatus for the energetic utilization of bioenergy carriers and other organic substances, consisting of a reactor which is designed to be heated indirectly and at one end has an inlet for the bioenergy carriers and other organic substances, and the reactor is provided with a transport device which is substantially above its The entire length inside the transport of bioenergy carriers and other organic substances realized, and the reactor has at least such a length that seen from the inlet in the transport direction at least first drying and subsequent pyrolysis of bioenergy carriers and other organic substances is substantially fully realized , And that another reactor is present, which is tapered down and at least in the region of its smallest cross-section, a supply of gases and / or gas mixtures and / or water vapor, and the reactor in the region of substantially union concluded pyrolysis of bioenergy carriers and other organic substances having an opening with a shaft-like guide in the direction of the lower tapered portion of the other reactor, which realizes the transport of at least the pyrolysis in the tapered portion of the other reactor, and wherein the further reactor at least one in the upper Having part located outlet opening for substantially gaseous products, which is associated with devices for energy recovery, characterized in that - at least a part of the reactor is located inside another reactor, and - the other reactor above the range of the exit of the pyrolysis in the a tapered portion has a channel-like built-in part, which is a cross-sectional limitation and forced guidance of upwardly moving wholly or partially reacted Pryolyseprodukte with the rejuvenating part of the gases and / or water vapor in the Realized area of the wall of the other reactor.

Description

The invention relates to the fields of power generation and mechanical engineering and relates to an apparatus and methods for generating energy from bioenergy sources and other organic substances, such as can be used for example for the production of heat and electric energy.

There are already known various methods for the gasification and combustion of organic substances, so-called bioenergy carriers whose energies are used thermally, chemically or electrically.

I. Obernberger (VDI Series 2000 "Renewable Energies in Hungary and Germany", Verlag GmbH (ed.) Dusseldorf, Germany pp. 59-101) are an overview of the currently known methods and devices for the thermal utilization of solid biogenic fuels to heat - and power generation listed. In addition to the known technologies of combustion, modern technologies of fixed bed gasification and fluidized bed gasification with downstream gas engines or gas turbines are also known.

In a fixed-bed gasifier, the fuel is exposed to the gasification agent in a packed bed. The individual pieces of fuel move in this layer of bulk material from the point of loading over different zones of the fuel bed to the place of the ashes. Depending on the material flow direction, a distinction is made between countercurrent or DC or cross-flow gasifiers, double-fired gasifiers or two-stage gasifiers.

In fluidized bed gasification, a distinction is made between stationary and circulating fluidized bed gasification. In a fluidized bed gasifier, the fine-grained fuel to be gasified (edge length should be less than 30 mm) flows through from below through a distributor plate of the oxidizing agent. After exceeding the maximum fluidization velocity of the gas, a fluidized bed with a defined surface is formed. This fluidized state is called a stationary fluidized bed. Above the fluidized bed there is a hot reaction zone through which the gases released from the fluidized bed pass and in which the gas can continue to react. As the gas velocity further increases, the fluidized bed expands until the solids are nearly evenly distributed throughout the reactor height. The fuel gas entrained by product gas is separated from the product gas in a downstream hot cyclone and returned to the reactor. This technology is called a circulating fluidized bed.

The disadvantages of the known methods and apparatus for fluidized bed gasification are a relatively high technical complexity and a low cold gas efficiency. Furthermore, the maintenance of a stable fluidized bed is still difficult.

The object of the invention is to provide a device and a method for generating energy from bioenergy carriers and other organic substances that works stably and has a higher cold gas efficiency than previously known gasification processes.

The object is achieved by the invention specified in the claims. Further developments are the subject of the dependent claims.

• – mindestens ein Teil des Reaktors sich im Inneren eines weiteren Reaktors befindet und,
• – der weitere Reaktor oberhalb des Bereiches des Austrittes der Pyrolyseprodukte im verjüngenden Bereich ein kanalartiges Einbauteil aufweist, das eine Querschnittsbegrenzung und Zwangsführung der sich nach oben bewegenden ganz oder teilweise umgesetzten Pyrolyseprodukte mit den im verjüngenden Teil eingetretenen Gasen und/oder Wasserdampf in den Bereich der Wandung des weiteren Reaktors realisiert.

The inventive device for the energetic utilization of bioenergy carriers and other organic substances, consists of a reactor which is formed indirectly heated and having at one end an inlet for the bioenergy carriers and other organic substances, and the reactor is provided with a transport device which substantially The transport of the bioenergy carriers and other organic substances is realized over its entire length in the interior, and the reactor has at least such a length that at least first drying and subsequently pyrolysis of the bioenergy carriers and other organic substances essentially completely takes place inside the inlet in the transport direction is realized, and that a further reactor is present, which is tapered down and at least in the region of its smallest cross-section has a supply for gases and / or gas mixtures and / or steam, and the reactor in the Area of substantially completed pyrolysis of bioenergy carriers and other organic substances having an opening with a shaft-like guide towards the lower tapered part of the other reactor, which realizes the transport of at least the pyrolysis products in the tapered part of the other reactor, and wherein the further reactor at least having an outlet opening in the upper part for substantially gaseous products, which is connected to devices for energy recovery, and according to the invention

• At least part of the reactor is located inside another reactor and
• - The further reactor above the region of the outlet of the pyrolysis in the tapered region has a channel-like built-in part, which is a cross-sectional limitation and forced guidance of the upwardly moving wholly or partially reacted pyrolysis with the occurred in the tapered part gases and / or water vapor in the region of the wall the other reactor realized.

Advantageously, the reactor for drying and pyrolysis of bioenergy carriers and other organic substances is tubular, with a round, oval, square or rectangular cross section.

Also advantageously, the reactor is arranged inclined for drying and pyrolysis of bioenergy carriers and other organic substances, wherein the inclination may be between 10 and 40 °.

Also advantageously, the reactor for drying and pyrolysis of bioenergy carriers and other organic substances inside a screw conveyor.

Furthermore advantageously, the further reactor is in the form of a cylindrical, rectangular, square or oval cross section and a cavity is formed in the interior.

It is advantageous that the further reactor is designed as a stationary hollow-cylindrical reactor.

It is also of advantage that the tapering part is designed as a circular frustum or truncated pyramid.

It is also advantageous that the shaft-like feed is tubular, with a round, oval, square or rectangular cross-section.

It is also advantageous that the opening in the reactor for drying and pyrolysis of bioenergy carriers and other organic substances is small compared to the diameter of the reactor.

And it is also advantageous that the channel-like built-in part is designed with a square or rectangular or trapezoidal cross-section.

A further advantageous embodiment of the device according to the invention consists in that the interior of the reactors is lined with fireclay materials.

And an advantageous embodiment of the device according to the invention is that the shaft-like feed and the channel-like built-in made of high temperature resistant ceramic or stainless steel.

And also advantageously, in the upper part of the other reactor, a device for dust separation and removal of dust is present.

• – mindestens der Bereich des Reaktors, in dem die Pyrolyse stattfindet, durch die indirekte Beheizung des weiteren Reaktors aufgeheizt wird, und
• – die Gase und/oder Gasgemische mit den gasförmigen und festen Pyrolyseprodukten im weiteren Reaktor eine solche Strömungsgeschwindigkeit aufweisen, dass sie ein Ablagern der Feststoffe verhindern und die Reaktionsprodukte mit der nach oben gerichteten Gasströmung transportiert werden, wobei die Gasströmung durch das kanalartige Einbauteil begrenzt und zwangsweise in Richtung der Reaktorwandung geführt wird.

In the method according to the invention for the energetic utilization of bioenergy carriers and other organic substances, the bioenergy carriers and other organic substances are introduced via the inlet into the reactor and transported with the conveyor inside, wherein in the inlet spatially subsequent part of the reactor, the bioenergy carriers and other organic substances first dried and then substantially pyrolyzed, and the gaseous and solid pyrolysis products and residues are passed through the opening in the reactor and the shaft-like feed in the tapered part of the other reactor to below the channel-like built-in part and there with the introduced gases and / or gas mixtures and / or steam mixed and fluidized and wholly or partially burned, gasified and cracked, then enter the upper part and a further reaction can be carried out, and the resulting gaseous n products of a plant for energy recovery, according to the invention

• - At least the region of the reactor in which the pyrolysis takes place, is heated by the indirect heating of the other reactor, and
• - The gases and / or gas mixtures with the gaseous and solid pyrolysis products in the other reactor have such a flow rate that they prevent deposition of the solids and the reaction products are transported with the upward gas flow, the gas flow through the channel-like built-in limited and forcibly is guided in the direction of the reactor wall.

Advantageously, the bioenergy carriers and other organic substances are used in the form of fine to mittelstückigem Good (edge lengths up to 50 mm).

Also advantageously be used as bioenergy sources and other organic materials, wood, straw, renewable resources and agricultural residues.

Also advantageously, the pyrolysis of bioenergy carriers and other organic substances in the last third of the reactor is realized.

And also advantageously, the energy input for pyrolysis on the indirect heating is partially realized by the combustion and gasification of the products in the other reactor.

It is also advantageous that through the forced guidance in the lower part of the further reactor through the channel-like built-in part, a turbulence of the pyrolysis products with the gas and / or gas mixture and / or steam flow is realized.

It is also advantageous that preheated air or steam is introduced into the further reactor.

It is likewise advantageous that the gas and / or the gas mixture and / or the steam are introduced under a pressure of up to 3.0 MPa.

Also advantageously, an upward gas, gas mixture and / or water vapor flow is realized in another reactor, which can be realized by suction of the gaseous reaction products and the introduced gas, gas mixture and / or water vapor.

By means of the invention, organic substances can be almost completely converted and, advantageously, small carburetors up to 800 kW of power can be realized.

The inventive method includes the drying and pyrolysis of the bioenergy carriers and other organic substances used at temperatures of 500-600 ° C in the reactor and the combustion, gasification and cracking of pyrolysis and residues at temperatures up to 1200 ° C in another reactor.

The drying of the organic substances in the drying region of the reactor is carried out by a circulating desiccant, preferably an air-water vapor mixture in the range of 200 ° C. The thus dried and forwarded by the conveyor bioenergy carriers and other organic substances are then in the pyrolysis section of the reactor at temperatures between 500-600 ° C in carbon monoxide, carbon dioxide, hydrogen, water vapor, volatile, long and short chain hydrocarbons and coal and pyrolysis essentially complete implemented. The complete conversion can be controlled by the conveying speed. This can be optimized depending on the specific bioenergy carriers used and other organic substances and the specific dimensions of the device. The gaseous and fast products of the pyrolysis stage and also possible non-pyrolyzed substances are then passed through the opening in the reactor and through the shaft-like guide in the lower tapered part of the other reactor. With the arrangement of the further reactor in the upright position and the guide directed downwards, the products fall into the tapered part of the further reactor. Simultaneously with these products, a gas flow from the bottom is realized upwards into the further reactor. For this purpose, gas or a gas mixture and / or steam is passed from below into the other reactor. On the one hand, this can be done under pressure or can be realized by suction in the upper region of the further reactor. In this case, at least one such flow rate is realized, which prevents deposition of the solid components in the tapered part of the other reactor. This can also be assisted by a corresponding arrangement of more than one inlet for the gas or gas mixture and / or water vapor. When gas / gas mixture / water vapor and the solid and gaseous pyrolysis products coming from above and possibly residues, the solid parts are entrained with the gas / gas mixture / steam stream. The gaseous components mix. This loaded gas / gas mixture / steam stream is directed upwards against a duct-like built-in part and deflected there, wherein a portion of this stream is returned to the underlying space and circulated there and part exits through the openings between the channel-like component and the reactor wall upwards , In this lower area essentially the complete conversion of solid and gaseous products takes place at temperatures up to 1300 ° C. In the presence of oxygen, solid components are burned, but essentially gasification of the solid components takes place. The gaseous long hydrocarbons are cracked. Depending on the flow rate, the products which are completely or substantially completely reacted reach the upper part of the further reactor after substantially all the times in a substantially gaseous state, where they realize the indirect heating of the reactor at least in part of the pyrolysis section. The implementation of solid components, which may not yet have taken place completely, can still be realized in the upper part. The end product of this process is a tarry crude gas as possible with the main energy sources hydrogen, methane and carbon monoxide. Still existing solid component can be discharged, for example via a dust deposit. The resulting crude gas is discharged or sucked from the other reactor and subjected, for example, a regenerative cooling and purification and then provided an afterburner and / or engine combustion for energy. The regenerative cooling of the raw gas from the process can be used to heat the gas or gas mixture introduced into the process.

With regard to the device has proved to be advantageous to arrange the reactor inclined, wherein in the lower part of the inlet is realized. A screw conveyor protrudes into the reactor and realizes the transport of the bioenergy carriers and other organic substances over the entire length of the reactor. The auger is adapted to the existing temperatures and determined by their speed, the residence time of bioenergy carriers and other organic substances in the reactor. Advantageously, the screw conveyor is shifted up in a hot running bearing, which allows a length compensation.

Furthermore, the invention will be explained in more detail using an exemplary embodiment.

The reactor used is a screw conveyor of 2.5 m length and 200 mm diameter with an internal conveyor spiral with a pitch of 50 mm. The inclination of the screw conveyor is 35 °. The screw conveyor is mounted in the lower area by a support bracket and provided with a drive. The screw conveyor passes through the standing arranged hollow cylindrical further reactor, so that substantially the last third of the screw conveyor is located in the interior of the other reactor. The passage is realized essentially in the central region of the further reactor. The screw conveyor has at the lowest point an inlet opening with an inlet funnel for the organic matter. Furthermore, in the lower region, the outer wall of the screw conveyor is provided with an opening through which the dry medium, a water vapor-air mixture enters the delivery chamber. In the area of completion of the drying area in the screw conveyor, approximately after 1 m, the drying medium emerges again via an outlet opening.

The screw conveyor transports 40 kg / h of wood chips with an average edge length of 30 mm.

At the end of the pyrolysis section within the screw conveyor, an opening of 100 mm diameter is present within the further reactor in the downwardly facing part of the screw conveyor housing, to which a pipe of 1 m in length is attached. The solid pyrolysis products fall down through this tube and the gaseous pyrolysis products also exit downwards. All products arrive in the lower part of the other reactor.

The further reactor has a height of 2.5 m and an inner diameter of 600 mm. The lower part of the further reactor is designed in the shape of a circular frustum and, in the region of its smallest diameter of 100 mm, has the inlet opening for an air / water vapor mixture.

Both the screw conveyor and the other reactor are lined with chamotte inside.

In the area of the transition from the circular frustum-shaped lower to the hollow-cylindrical upper part of the further reactor, a channel-like installation part of trapezoidal cross-section is installed. This built-in part is made of high-fire-resistant ceramic. Through this built-in part, the tube is guided out of the screw conveyor, so that the pyrolysis products are in each case passed below the built-in part in the other reactor.

Upon impact of the solid pyrolysis products, coal and coke on the air / steam stream, which leads upwards at a flow rate of 15 m / s, the solid constituents are broken up, partially burned, gasified and the gaseous pyrolysis products cracked. When flowing upward, the loaded stream hits the fitting, is deflected and swirled. One part of the stream circulates and another part passes through the openings between the installation part and the reactor wall into the space above the built-in part. In the space below the built-in part is a temperature in the range of 1100 to 1300 ° C before. In the room above the built-in part, the gas cools down and temperatures between 700 and 800 ° C are reached. At the same time, the screw conveyor is indirectly heated in the pyrolysis area.

The extracted in the upper part of the other reactor with a fan raw gas is further processed in an amount of 200 m ³ / h. This raw gas has a capacity of about 150 kW. Further processing takes place via regenerative cooling and cleaning and subsequent combustion in an engine.

Claims (25)

Apparatus for the energetic utilization of bioenergy carriers and other organic substances, consisting of a reactor which is designed to be heated indirectly and at one end has an inlet for the bioenergy carriers and other organic substances, and the reactor is provided with a transport device which is substantially over its The entire length inside the transport of bioenergy carriers and other organic substances realized, and the reactor has at least such a length that seen from the inlet in the transport direction at least first drying and subsequent pyrolysis of bioenergy carriers and other organic substances is substantially fully realized , And that another reactor is present, which is tapered down and at least in the region of its smallest cross-section, a supply of gases and / or gas mixtures and / or water vapor, and the reactor in the region of substantially union concluded pyrolysis of the bioenergy carriers and other organic substances having an opening with a shaft-like guide in the direction of the lower tapered portion of the other reactor, the transport of at least the pyrolysis products in the tapered part of the other Realized reactor, and wherein the further reactor comprises at least one located in the upper part outlet opening for substantially gaseous products, which is connected to apparatus for energy recovery, characterized in that - at least a part of the reactor is located in the interior of another reactor and, - The further reactor above the region of the outlet of the pyrolysis in the tapered region has a channel-like built-in part, which is a cross-sectional limitation and forced guidance of upwardly moving wholly or partially reacted Pryolyseprodukte with the rejuvenating part of the gases and / or water vapor in the region of the wall the other reactor realized. Apparatus according to claim 1 wherein the reactor is tubular, circular, oval, square or rectangular in cross-section for drying and pyrolysis of the bioenergy sources and other organic matter. Apparatus according to claim 1, wherein the reactor is arranged inclined for drying and pyrolysis of the bioenergy carriers and other organic substances. Apparatus according to claim 3, wherein the inclination is between 10 and 40 °. Apparatus according to claim 1, wherein the reactor for drying and pyrolysis of bioenergy carriers and other organic substances inside contains a screw conveyor. Apparatus according to claim 1, wherein the further reactor is formed with a cylindrical, rectangular, square or oval cross-section, wherein there is a cavity in the interior. Apparatus according to claim 1, wherein the further reactor is formed as a stationary hollow cylindrical reactor. Apparatus according to claim 1, wherein the tapered portion is formed of a circular frustum or truncated pyramid. Apparatus according to claim 1, wherein the duct-like feed is tubular, round, oval, square or rectangular in cross-section. Apparatus according to claim 1, wherein the opening in the reactor for drying and pyrolysis of the bioenergy carriers and other organic substances is small compared to the diameter of the reactor. Apparatus according to claim 1, wherein the channel-like mounting part is designed with a square or rectangular or trapezoidal cross-section. Apparatus according to claim 1, wherein the interior of the reactors is lined with refractory materials. Apparatus according to claim 1, wherein the shaft-like feed and the channel-like mounting part of high temperature resistant ceramic or stainless steel. Apparatus according to claim 1, wherein a device for separating out dust and discharging the dust is present in the upper part of the further reactor. Process for the energetic utilization of bioenergy carriers and other organic substances in a device according to one of claims 1 to 14, in which the bioenergy carriers and other organic substances are introduced into the reactor via the inlet and transported inside with the conveyor, wherein the inlet is spatially Subsequently, the bioenergy carrier and other organic substances are dried first and then substantially pyrolyzed in the subsequent part of the reactor, and the gaseous and solid Pyrolsyeprodukte and residues are passed through the opening in the reactor and the shaft-like feed in the tapered part of the other reactor to below the channel-like Einbauteiles and there mixed with the gases introduced and / or gas mixtures and / or steam and swirled and burned completely or partially, gasified and cracked, then enter the upper part and a further implementation can be performed k ann, and the resulting gaseous products are fed to a plant for energy recovery, characterized in that - at least the region of the reactor in which the pyrolysis takes place, is heated by the indirect heating of the other reactor, and - the gases and / or gas mixtures with the gaseous and solid pyrolysis in the other reactor have such a flow rate that they prevent deposition of the solids and the reaction products are transported with the upward gas flow, wherein the gas flow is limited by the channel-like component and forcibly guided in the direction of the reactor wall. Process according to claim 15, in which the bioenergy carriers and other organic substances are used in the form of fine to medium-sized material (edge lengths up to 50 mm). A method according to claim 15, in which bioenergy carriers and other organic substances, wood, straw, renewable raw materials and agricultural residues are used. Process according to Claim 15, in which the pyrolysis of the bioenergy carriers and other organic substances is realized in the last third of the reactor. The method of claim 15, wherein the energy input for pyrolysis via the indirect heating is partially realized by the combustion and gasification of the products in the further reactor. The method of claim 15, wherein by the forced guidance in the lower part of the further reactor through the channel-like mounting part, a turbulence of the pyrolysis products with the gas and / or gas mixture and / or steam flow is realized. The method of claim 15, wherein preheated air is introduced into the further reactor. Process according to Claim 15, in which steam is introduced into the further reactor. Process according to Claim 15, in which the gas and / or the gas mixture and / or the steam are introduced under a pressure of up to 3.0 MPa. The method of claim 15, wherein an upward gas, gas mixture and / or water vapor flow is realized in another reactor. A method according to claim 24, wherein the upwardly directed gas, gas mixture and / or water vapor flow is realized by suction of the gaseous reaction products and the introduced gas, gas mixture and / or water vapor.