WO2003004942A1

WO2003004942A1 - Reactor for using solar radiant heat

Info

Publication number: WO2003004942A1
Application number: PCT/CH2002/000361
Authority: WO
Inventors: Wolfgang Hoffelner; Aldo Steinfeld; Daniel Wuillemin; Anton Meier; Beatrice Schaffner
Original assignee: Paul Scherrer Institut
Priority date: 2001-07-05
Filing date: 2002-07-03
Publication date: 2003-01-16
Also published as: WO2003004942A8; AU2002315618A1

Abstract

The invention relates to a reactor for using solar radiant heat for thermal or thermochemical processes. Said reactor comprises a reactor housing (1, 101) having an opening (2a, 125) for allowing solar radiation into the reactor housing (1, 101), a reaction chamber (13, 117), and a volumetric absorber (2, 102) which is heated on a front side (2b, 102b) by means of the solar radiation and which releases heat into the reaction chamber (13, 117). Said absorber (2, 102) is a black body absorber which is arranged in a hearth (4, 109) and which introduces heat into the hearth (4, 109) from a rear side (2c, 126) thereof. The inventive reactor especially has the advantage that the heat can be released indirectly onto the product to be treated, over an essentially larger surface than before.

Description

Reactor for the use of solar radiant heat

The invention relates to a reactor for using solar radiant heat for thermal or thermochemical processes, with a reactor housing, an opening for the entry of solar radiation into the reactor housing, a reaction chamber and an absorber which is heated by the solar energy on a front side and heat in the Gives reaction space.

A reactor of this type has become known in the prior art from US 4,706,651. This has a stationary chamber, into which solid material is fed through a rear wall, which material is subjected to a reaction in the chamber. A window is arranged opposite this rear wall, through which solar radiation is introduced into the chamber. An absorber, which is designed as an endless band and is provided with reflecting parts, is arranged below an upper horizontal wall of the reactor housing. The energy radiated through the window into the reaction space is reflected on this band and reflected down to the solid material introduced. This material is transported on a screw conveyor and heated in the process. The material is transported by a screw during the irradiation. After the heat treatment, the material is removed in the area of the window.

No. 4,432,344 discloses a reactor which is intended in particular for the thermochemical and thermal treatment of organic material by means of solar energy. In this reactor, the reaction chamber is a tube into which solar energy is is radiated and in which solar energy is introduced through a side window by means of a mirror. Reference is also made to the similar US 4,549,528.

US 5,421,322 discloses a solar receiver which is provided for the production of energy. The solar radiation is introduced through a window against a rotating reflector and deflected through this reflector against an absorber. The absorber is located in a chamber in which a liquid to be heated circulates. The device is not a reactor.

The invention has for its object to provide a reactor of the type mentioned, which is even better suited for the use of solar radiant heat for thermal and thermochemical processes of different substances and in particular for a flat treatment of such substances.

The object is achieved in the reactor according to the invention in that the absorber is a volumetric black-body absorber which is arranged in a stove and which brings heat into the stove with a rear side. In the reactor according to the invention, the blackbody absorber is heated by solar energy and the heat is radiated into the hearth via a rear side. As a result, the heat can be dissipated indirectly onto the material to be treated over a much larger area than before. The reactor according to the invention is particularly suitable for the treatment of various types of dusts. Volatile elements, such as zinc or lead, can also be evaporated particularly effectively. Flammable substances, for example shredder residues, can also be pyrolyzed, discharged as pyro-coke and fed to further treatment, for example in a hot cyclone. The reactor according to the invention is particularly suitable for the disposal of household batteries, the organic components of which are thermally decomposed in a radiation space of the reactor.

According to a development of the invention, the absorber is essentially designed as a rotating body that is open on one side. This allows a comparatively large back to be formed, which radiates across the stove. Preferably, the stove is also essentially designed as a rotating body open on one side. As a result, an approximately U-shaped radiation or reaction space can be formed in the axial section, in which the treated material is heated. The absorber is preferably essentially U-shaped in cross section. Particularly suitable conditions arise when the absorber and / or the cooker are driven in a rotatable manner.

The reactor is particularly suitable for treating used household batteries if, according to a further development of the invention, the absorber is provided with a heated transport screw, via which the organic components of the household batteries are thermally decomposed during transport. The metallic components of the household batteries are melted in a radiation chamber arranged after the transport screw.

Further advantageous features result from the dependent claims, the following description and the drawing.

Two exemplary embodiments of the invention are explained in more detail below with reference to the drawing. Show it: Fig. 1 shows schematically a section through an inventive reactor and

Fig. 2 shows schematically a section through a variant of the reactor according to the invention.

The reactor according to FIG. 1 has a reactor housing 1, into which an absorber 2 is inserted from the top, which is seated tightly on a support la and which has an upper opening 2a, which is covered by a translucent window 3. The absorber 2 is a black body absorber and has a front side 2b and a rear width 2c. It is made of a high-melting material, preferably graphite. In the radial section, the absorber 2, as can be seen, is U-shaped, the irradiation opening 2a being at the top. The outside of the absorber 2 radiates into a hearth 4, which is also mounted in the reactor housing 1 and which is preferably lined with a refracture 5 on the inside. The refracture 5 is made of a heat-insulating material, for example chamotte. The hearth 4 is rotatably mounted on a support 10 fastened to the reactor housing 1 with a rotary bearing 9. The cooker 4 can be rotated about an axis A by means of a drive 11, for example a motor. In a bottom area 4a, the cooker 4 has a material outlet 6 which has a rotary slide 7. By extending and tilting this rotary valve 7, material B can be conveyed into a collecting vessel 8. The material B is in a likewise somewhat U-shaped space on average, which is arranged between the cooker 4 and the absorber 2.

The material B is introduced into the room 13 for its treatment by means of a feeding device 12, which has, for example, a screw conveyor, not shown here. The. Material B moves in space 13 from above due to its gravity down to the floor area 4a. During this movement, the material B is exposed to the radiant heat of the absorber 2. This radiant heat leads to the desired thermal or thermochemical reaction in material B. It is important here that the absorber 2 radiates with its rear face 2c over a large area and thereby heats the material B. The material B is also exposed to the radiant heat of the refracture 5.

If a certain layer has formed with treated material B in the bottom region 4a, this material B is applied via the outlet 6 by means of the rotary valve 7 or another suitable device and falls into the collecting vessel 8.

If flue gases arise during the treatment of material B, these are conveyed away via a flue gas outlet 14 and are passed on to a suitable further treatment. If combustible gases arise, they can be burned in an afterburning chamber (not shown here) for energy generation. Some of the hot gases can be directed against the cooker 4 via a feed 15 via nozzles 16 for heating the cooker 4. The flue gases generated during this heating of the cooker 4 are fed via a flue gas pipe 17 to a flue gas cleaning system, not shown here. Heating the cooker 4 with hot gases has the advantage that the reactor can also be operated using separate energy sources in the event of missing or insufficient solar radiation. The combustion chamber C is sealed off from the chamber 13 and a discharge chamber 21 by seals 18 and 19.

The material B can be organic, inorganic or metallic material or else a mixture or a mixture thereof. The reactor is particularly suitable for the treatment of dusts. various types. In particular, volatile elements such as zinc or lead can be evaporated from such dusts and recovered from the flue gas. However, combustible materials, for example shredder residues, can also be pyrolyzed and discharged as pyrocoke and sent for further treatment. For example, such further treatment can take place in a hot cyclone.

The reactor shown in FIG. 2 is particularly suitable for abrasive or bulky material in which the initial reaction is to take place at comparatively low temperatures, for example pyrolysis at 500 ° -600 ° C. The reactor has a gas-tight reactor housing 101, in an absorber part 102 is inserted from above, which has a carrier 104 on which the absorber 102 is rotatably mounted. An upper irradiation opening 125 is covered with a window 103. The absorber 102 is in direct contact with the carrier 104 and heats it. On the outside, a conveyor screw 105, which is only indicated here, is attached to the carrier 104 and conveys the material C to be treated in a space 117 from top to bottom.

The absorber 102 is rotatably mounted with the carrier 125 on a bearing 6 about the axis A and can be rotated by means of a drive 107. The carrier 125 is sealed off from the reactor housing 101 with a seal 8.

The absorber 102 engages in a stove 109 with which it forms the space 117 mentioned. As can be seen, the absorber 102 is U-shaped in the axial section and this also applies to the space 117. The hearth 109 is firmly connected to the reactor housing 101 by means of a support 115. However, a rotatable arrangement of the cooker 109 is also conceivable here. A refracture 10 is arranged on the inside of the cooker 109 and extends into a bottom region 109a of the cooker 109. A material outlet 111 is arranged in the center of this floor area 109a and has a retraction table 113 which is arranged in a mold shell 112 so as to be vertically displaceable. The lifting movement of the retraction table 113 takes place by means of a hydraulic drive 114 which is fastened to the reactor housing 101. The retreat table 113 is preferably cooled and is moved downward to form a mold in accordance with the amount of treated material C. Such devices are known per se in metallurgy when melting high-performance materials.

The material C to be treated is introduced into the space 117 via a loading device 16. The absorber 102 and the carrier 104 connected to it are continuously rotated about the axis A by the drive 7. If necessary, the cooker 109 can also rotate at the same time. The material C introduced into the space 117 from above is conveyed downward by the transport screw 105 and comes into the area of a rear side 126 of the absorber 102 and is thus exposed to the radiant heat of the absorber 102. Above this area, the material C is exposed to the radiant heat of the carrier 104, which is, however, significantly lower than that in the lower area mentioned above. In the upper area, for example, pyrolysis is carried out at 500-600 ° C. In the lower area, material C is melted, for example. Molten material C reaches the retraction table 113, which is slowly withdrawn downwards in accordance with the accumulation of molten material.

The flue gases generated during the processing of material C are fed to a further treatment via a flue gas outlet 118 in a device (not shown here). Such Suitable flue gas treatments are known to the person skilled in the art. If combustible gases arise, they are burned in an afterburning chamber (not shown here) for energy generation. Some of the hot gases produced here are directed against the stove 109 via a feed 119 at nozzles 120 for heating the stove. The resulting flue gases are fed through a flue gas pipe 121 to a flue gas cleaning device, not shown here. The stove 109 can be heated using separate energy sources in the case of missing or insufficient solar radiation via the nozzles. In order to protect the space 117 and a discharge chamber 127 from hot fuel gases, the combustion space 128 is sealed to the outside by seals 122 and 123. Missing energy in the lower region of the cooker 109 can be introduced by means of an additional heater 124. The auxiliary heater 124 is preferably an induction heater.

For the disposal of used household batteries, the organic components of these batteries are thermally decomposed during transport in the area of the transport screw 105. In the lower area, the metallic components are melted at higher temperatures and, as explained above, collected on the retraction table 113. The disposal of household batteries is just one example of the thermal or thermochemical treatment of material C.

Claims

claims

1. Reactor for the use of solar radiant heat for thermal or thermochemical processes, with a reactor housing (1, 101), an opening (2a, 125) for the entry of solar radiation into the reactor housing (1, 101), a reaction space (13, 117 ) and a volumetric absorber (2, 102), which is heated on a front side (2b, 102b) by the solar radiation and emits heat into the reaction space (13, 117), characterized in that the absorber (2, 102) is a blackbody -Absorber, which is arranged in a stove (4, 109) and which brings heat into the stove (4, 109) with a rear side (2c, 126).

2. Reactor according to claim 1, characterized in that the absorber (2, 102) is a rotating body open on one side.

3. Reactor according to claim 2, characterized in that the absorber (2, 102) is U-shaped in axial section.

4. Reactor according to 'one of claims 1-3, characterized in that the absorber (2, 102) and / or the stove (4, 109) are rotatably driven.

5. Reactor according to one of claims 1-4, characterized in that the absorber (2, 102) is designed as a pure radiator. '

6. Reactor according to one of claims 1-5, characterized in that the absorber (102) is at least partially designed as a heated manipulator.

7. Reactor according to claim 6, characterized in that the absorber (102) has transport means (105), in particular a transport screw.

8. Reactor according to one of claims 1-7, characterized in that the absorber (2, 102) has a window (3, 103) for the entry of solar radiation.

9. Reactor according to one of claims 1-8, characterized in that the hearth (4, 109) has on the inside a refracture (5, 110) facing the absorber (2, 102).

10. Reactor according to one of claims 1-9, characterized in that the hearth (4, 109) has a material outlet (6, 111).

11. Reactor according to claim 10, characterized in that the material outlet (106) has a slide (7), in particular a rotary slide.

12. Reactor according to claim 10, characterized in that the material outlet (11) has a back ^' feed table (113) which is slidably mounted in a mold shell (112).

13. Use of the reactor according to claim 1 for the disposal of batteries, in particular household batteries, these being treated in the region of a transport device (105) for decomposing organic components at a comparatively low temperature and treated in a further region at a higher temperature and thereby melting metallic components ,

4. Use of the reactor according to claim 1 for the treatment of dusts, volatile elements such as zinc or lead being evaporated and recovered from the flue gas.