EP2297519B1 - Method and device for feeding conveyable materials to reaction furnaces - Google Patents

Description

The invention relates to a method and an apparatus for feeding eligible materials to reaction furnaces.

"Materials" within the meaning of this invention also include mixtures of materials. "Eligible" in the sense of this invention means that the material is free-flowing and / or free-flowing and / or pourable and / or pasty. The teaching according to the invention can be used advantageously in particular for supplying mixtures of comminuted, dry or liquid-mixed waste materials in incinerators. Advantageous applications are the supply of fuel in furnaces for cement production or in the pressure zone of shaft furnaces for the production of pig iron that is under considerable overpressure relative to the atmosphere.

The materials to be delivered may include solid parts and liquids. Size distribution and type of solids, as well as type and proportion of liquids contained can vary within wide ranges. The solids contained may be or contain hard particles (eg metal parts, mineral constituents, siliceous constituents) and softer parts such as natural or artificial fibers, textile parts, animal and vegetable wastes, plastics and foams. The liquids can be different in many areas. (Water, oils, greases, paints, adhesives, other chemicals, tar, ....).

In particular, the supply of bulk material, which is obtained as a light fraction in the shredding of waste, is substantially dry and contains a considerable proportion of fibers or fibrous parts and hardly any metal is considerably simplified by the invention. Based on the weight of such bulk material normally has a respectable calorific value.

The AT 502 048 B1 describes a method and apparatus for feeding bulk material having solids and liquids to a processing plant. After the bulk material has been conveyed to the system only under ambient pressure with non-operating conveyors, it is pressurized by a pump and thereby conveyed through a narrow lance into the system. The method is only applicable if the material is actually pumpable, which is unfortunately not true for many bulk materials, especially those that contain little liquid.

The DE 199 09 132 A1 describes a supply of bulk materials by means of a pneumatic conveying path from a storage container to a cupola. Storage tank and conveyor string are under higher gas pressure than the cupola. Air flowing out of the conveyor line conveys bulk material into the oven at a relatively high speed. Due to these conditions, burn-back from the furnace into the conveyor system is practically impossible. The problem with the design is that the functionality depends strongly on the properties of the bulk material and that with the bulk material a lot of air is introduced into the cupola, so that the proper control of the combustion is more difficult. Normally, the storage container is not directly at the implementation site through the furnace wall, but typically ten to a hundred meters away. From a storage container several implementation sites are supplied by the furnace wall. This results in the requirement of long, not continuous straight strands for the pneumatic conveying, so that the Feeding process with minimal changes in the material properties of the material to be conveyed or pressure fluctuations in the cupola is extremely prone to failure.

In the EP 0 060 137 A1 a pneumatic conveyor for granular fuel is proposed. In the storage container for the material, the same air pressure prevails as in the conveyor line. The discharge of the material from the reservoir and thus the supply to the pneumatic conveying path takes place with the aid of a screw conveyor working as a screw conveyor. This is at least the controllability of the amount of material introduced into the conveyor line slightly less dependent on the properties of the bulk material over the previously discussed methods. Otherwise the same problems exist as with the DE 199 09 132 A1 ,

The EP 48008 A1 . EP 299231 A1 . EP 302047 A1 . WO 9746719 A1 . WO 99/1825 A1 and the WO 200148251 A1 deal with the so-called Corex process for crude steel production. From a raw material container, the free-flowing granular raw material is passed over a drop-down path formed by a pressure-tight pipeline into the reaction space below the raw material container. In this case, either the metered discharge of the raw material from the raw material container or the metered supply of the raw material from the vertical fall distance into the reaction space by means of a short, straight line in the horizontal direction promoting metering screw.

The same application of dosing screws is also shown by the US 17 94455 A in which, however, the furnace chamber is not under elevated pressure.

In the EP 0 662 926 B1 and in the DE 102 02 490 C1 It is proposed by means of screw conveyor from a reservoir in which a lower pressure prevails in a furnace to promote higher pressure. The required sealing between the two areas is to be achieved by providing an area of reduced cross-sectional area in the conveying area of the screw is completely filled by the material to be promoted. The method can only work for bulk solids with a high moisture content and for relatively low pressures, since otherwise insufficient tightness can be achieved. The densification of the material reduces its specific surface area, which leads to difficulties in burning in the furnace.

The DE 2 249 453 A1 shows a granular fuel supply device to a pressurized furnace chamber by means of two screw conveyors. A first auger conveys the material away from a non-pressurized sampling point and compresses it at its end to a tight stopper. On the furnace side, the plug is scraped by a device again and the mashed material is fed through a second screw conveyor to the furnace. The second conveyor line is under the pressure prevailing in the oven room. If anything, the proposed method can work only for a very narrow group of materials to be conveyed, and only at low pressures, and certainly requires a lot of supervision and maintenance. A method and a device according to the preamble of claims 1 and 7 is in the document DE 4338161 A1 disclosed.

The object underlying the invention is to provide a method and an apparatus for the feeding of eligible material to and in reaction furnaces, in which also an overpressure can prevail. The conveying should be robust against variations in composition, particle size distribution and other material properties of the material being conveyed. It should also dry material whose particles to pipe walls, etc. have a high coefficient of friction, can be supplied. It should not necessarily be necessary, together with the material to be conveyed to introduce a high proportion of conveying air or conveying gas in the reaction furnace.

The often difficult space pressure and temperature conditions in the area of the passage through the furnace wall should be well catered for.

The conveying should work safely and robustly even with very long conveyor lines, which may also include directional changes, rising sections and distribution points.

To solve the problem, it is proposed that the material to be conveyed within a pressure-sealed by the outside air cavity, in which there is substantially a relation to the furnace pressure at least slightly elevated gas pressure, to promote the reaction furnace zoom. In this case, the cavity opens into the furnace chamber through a connecting tube, which is designed as a lance, which has a reduced cross-sectional area in relation to the upstream conveying strand. The material to be conveyed is moved into the initial region of the lance with the aid of a non-pressure mechanical conveyor.

As a result of the overpressure, an air or gas stream flows from the pressure-tight sealed by the outside air cavity through the lance into the furnace chamber.

In the cavity which forms the conveying path, the material is introduced either via a pump or via a lock and a closed in the operating condition of the outside air reservoir. In the embodiment with lock advantageously the reservoir itself is designed as a lock.

The fact that the promotion takes place in a closed off from the outside air cavity in which the gas pressure is at least slightly higher than the furnace pressure, the risk of burn-back from the oven is either not given or well controlled. In the cavity devices such as rotary valves, pendulum flaps, burn-back sensors which trigger a foreclosure to the furnace chamber or similar acting devices, which should prevent burnback and kickback from the oven space and yet to be conveyed in normal operation material to be conveyed become superfluous or they can be simpler and thus be executed cheaper. The funding in the production line need not work contrary to a higher furnace pressure, making the conveying is much easier.

Due to the small cross-sectional area of the lance leading through the furnace wall, the space requirement on the furnace wall is low and the backpressure from the furnace does not lead to great forces, which tend to push the lance away from the furnace. By flowing an air or gas stream from the area in front of the lance through the lance into the furnace, the lance is cooled.

In a very advantageous embodiment, the material to be conveyed is also moved to lying away from the furnace areas of the conveyor line within the pressure-tight closed by the outside air cavity by means of pressure-free working mechanical conveyor. Within the pressure-sealed by the outside air cavity pressure-free mechanical conveyors are used not only for direct discharge from the reservoir or for direct entry into the reaction furnace, but especially on those sections of the conveying path, which completely of reservoir and reaction furnace several meters far lie away. It is particularly advantageous to apply such conveyors on upwardly leading and / or curved sections and / or before and after branching points of the conveying section, since in these sections other conveying means are increasingly problematic.

Pressure-free mechanical conveyors in the sense of this invention are those in which it is not necessary for the conveying function that propagates a pressure in the material to be conveyed along the conveying path, or that a gaseous or liquid conveying medium moves the material to be conveyed, but in the material to be conveyed is moved substantially by direct contact with a moving surface of the conveyor. A non-pressurized mechanical conveyor generally causes no division of the conveyor line in different pressure ranges. An example of such a conveyor is a conveyor belt. Regardless of the length of the conveying path, the non-pressurized delivery does not change the pressure in the conveyed material or in the gas surrounding the material. This makes it possible without any problems, unlike pressurized conveyors, the conveyor line is very long and also rising and / or angled and / or curved form. Thus, the reservoir from which material is conveyed away, be located very far away from the reaction furnace, which space problems can be avoided on the furnace.

In particular, it is advantageous to promote such pressure-free mechanical conveyors, by which a stream of the conveyed material is decomposed into a series of small, mutually separated moving subsets. This means conveyors such as chain conveyors, spiral conveyors, centrifugal conveyors, belt conveyors with carriers, cup conveyors, etc., in which the total amount of the material to be conveyed is divided by moving parts of the conveyor into small subsets, which are moved without any between successive subsets Pressure is exercised. (In contrast, for example, are the promoted by a piston pump at each stroke subsets in the subsequent pipeline to each other and it is essential for the delivery function in the pipeline that these subsets exert a pressure on each other).

By introducing the material into the cavity via a lock and reservoir and not through a pump, it never needs to be compacted, which would degrade the burn-off behavior, and less maintenance is required. If the reservoir is advantageously itself designed as a lock, the reservoir is alternately once associated with the outside air and filled in this state, and secondly decoupled from the outside air, connected to the pressure-tight closed by the ambient air cavity and emptied into this.

The feeding of eligible materials to reaction furnaces zoom in a closed by the outside air cavity by means of pressure-free working mechanical conveyor is particularly advantageous in combination with a connecting pipe to the furnace interior, which is designed as a lance, which has a relation to the upstream conveyor strand reduced cross-sectional area. But it is also useful in almost every other embodiment of the implementation through the furnace wall.

The combination of non-pressurized mechanical conveyor and air or gas flow for introducing the material to be conveyed into the lance and through the lance, both the weaknesses of mechanical conveyors, namely relative slowness and heat sensitivity, and the weaknesses of pneumatic conveyor lines, namely clogging susceptibility and high air or gas demand bypassed and yet the strengths of each method are fully utilized.

Preference is conveyed by means of a screw conveyor in the initial region of the lance, since this structure is simple and robust.

Further preferred is promoted by an axisless screw conveyor in the initial region of the lance, as this constipation is particularly well prevented and the air or gas flow into the lance is little impeded.

But it may also be advantageous to promote by a blast wheel in the initial region of the lance, as by such an introduced material is loosened very well.

The risk of clogging at the entrance to the lance can be particularly well reduced by the fact that from the side of the non-pressurized mechanical conveyor ago, the tip of a pointed hollow body protrudes to the input of the lance and that in the region of the tip of this body from a or more orifices of air or gas, which is in the body at a higher pressure than the furnace pressure. The pointed body may be formed by the hollow axis of an axle-guided auger.

Preference is given within the pressure-sealed by the outside air cavity even before the area of the lance by means of axleless screw conveyors promoted. This can cost, space-saving, low maintenance and high security against clogging a wide range of materials with different conveying properties are transported over long distances.

By using the non-pressure mechanical conveyor resulting in the production line no compression of the material to be moved, but on the contrary rather a loosening. This loosening influences the burn-off behavior of the conveyed material in the furnace advantageous.

Regardless of the length of the conveying path, the non-pressurized delivery does not change the pressure in the conveyed material or in the gas surrounding the material. Thus, unlike pressurized conveyors, it is easily possible to design the conveyor line very long and also rising and / or angled and / or curved.

A first additional aspect of the invention relates to a method for feeding eligible materials to a reaction furnace by a pressure-tight sealed from the outside air, opening into the furnace chamber via a connecting tube cavity, wherein the materials via a lock and a reservoir whose interior in the operating state with the is closed by the outside air pressure sealed cavity, are introduced into this cavity and therein in at least one stretch, which is located both from the reservoir and from the furnace, are conveyed with at least one non-pressure mechanical conveyor.

In an advantageous embodiment of this additional aspect is promoted within the pressure-tight sealed by the outside air cavity by means of axleless screw conveyors.

In a further advantageous embodiment of this additional aspect, the connecting tube of the pressure-tight closed by the ambient air cavity towards the furnace chamber is formed as a lance, which is opposite to the upstream conveying line has reduced cross-sectional area and through this lance flows an air or gas stream into the furnace chamber. In an advantageous embodiment of this, is conveyed by a non-operating mechanical conveyor into the initial region of the lance.

In a further embodiment of the additional aspect of the invention so that waste and / or residues are promoted in the pressure zone of a shaft furnace for crude steel production.

A second additional aspect of the invention relates to a device for feeding eligible materials to a reaction furnace by a pressure-tight sealed from the outside air, opening into the furnace chamber via a connecting tube cavity, wherein the device comprises a lock for the materials and a reservoir, wherein the reservoir is connected in the operating state with the pressure-sealed by the outside air cavity, and wherein in this cavity in at least one stretch, which is located both from the reservoir and from the furnace, at least one non-pressure working mechanical conveyor is arranged.

In an advantageous embodiment of this second additional aspect prevails in the cavity a relative to the furnace chamber elevated air or gas pressure prevails and the connecting pipe to the furnace chamber is formed as a lance, which has a relation to the upstream conveyor strand reduced cross-sectional area.

In a further embodiment of the second additional aspect of the invention, a pressure-less mechanical conveyor is arranged in the cavity in front of the connecting tube to the furnace chamber forming lance, the effect of which extends into the initial region of the lance. In an advantageous embodiment of this non-pressure working mechanical conveyor is an axisless screw conveyor. In another advantageous embodiment of this non-pressure working mechanical conveyor is a blast wheel.

In a further embodiment of the second additional aspect of the invention, the pressure-tight sealed from the outside air cavity is filled with inert gas. In an advantageous embodiment, the pressure-tight closed by the outside air cavity comprises a reservoir formed as a mixer.

In a further embodiment of the second additional aspect of the invention, the conveyed materials are waste and / or residues and the conveyor line opens into the pressure zone of a shaft furnace for crude steel production.

• Fig. 1: zeigt eine Prinzipskizze zu einem ersten Ausführungsbeispiel.
• Fig. 2: zeigt eine Prinzipskizze zu einem zweiten Ausführungsbeispiel.
• Fig. 3: zeigt eine Prinzipskizze zu einem dritten Ausführungsbeispiel.
• Fig. 4: zeigt eine Prinzipskizze zu einem vierten Ausführungsbeispiel.

Embodiments of the invention and further advantageous details will be explained with reference to figures. Showing:

• Fig. 1 : shows a schematic diagram of a first embodiment.
• Fig. 2 : shows a schematic diagram of a second embodiment.
• Fig. 3 : shows a schematic diagram of a third embodiment.
• Fig. 4 : shows a schematic diagram of a fourth embodiment.

1

in den Ofen zu förderndes, Material

2

Vorratsbehälter (im Betrieb von Außenluft getrennt)

3

Schneckenförderer

4

Übergaberaum innerhalb Förderstrecke

5

Schneckenförderer am Ende der Förderstrecke

6

Lanze, welche in den Ofenraum führt

7

Ofenraum

7.1

Ofenwand

8

pneumatische Förderstrecke

12

Pumpe, welche das zu fördernde Material pumpt

13

flexibler Schneckenförderer

14

Übergaberaum innerhalb Förderstrecke

15

Schleuderrad

21

Luftpumpe

22

Luftpumpe

23

Druckluftleitung

24

Druckluftleitung

25

Luftpumpe

26

Luftpumpe

27

Luftpumpe

33

Schneckenförderer

p1

Druck im Förderstrang

p2

Druck im Ofenraum

In the figures, the reference numerals denote the following:

1

to be conveyed in the oven, material

2

Reservoir (separated from outside air during operation)

3

screw conveyor

4

Transfer room within conveyor line

5

Screw conveyor at the end of the conveyor line

6

Lance, which leads into the oven room

7

furnace

7.1

furnace wall

8th

pneumatic conveyor line

12

Pump which pumps the material to be pumped

13

flexible screw conveyor

14

Transfer room within conveyor line

15

blower

21

air pump

22

air pump

23

Compressed air line

24

Compressed air line

25

air pump

26

air pump

27

air pump

33

screw conveyor

p1

Pressure in the conveyor line

p2

Pressure in the oven room

According to Fig. 1 is conveyed from a reservoir 2, however, any discharged material 1 by means of one or more screw conveyors 3 to a transfer room 4 and from this using a further screw conveyor 5 through a trained as a pipe lance 6 through an opening in the furnace wall 7.1 in the furnace chamber. 7 brought. Reservoir and conveyor line are completed by the outside air and are at least under the same high air pressure (or gas pressure) p1 as the pressure level p2 in the oven chamber. 7

The screw conveyors 3, 5 divide the flow of material 1 in the feed train into small batches, which are each arranged between two screw flights and push them forward in the conveying direction. There is no compression of the material, because unlike a pressurized promotion in a pressure tube no strand occurs in which over a considerable distance each rear material lying front material against the friction on pipe walls must continue to push. The storage container 2 or a pump which can be used instead can thus also be placed far away from the reaction furnace in which the material is to be conveyed. This space problems in the vicinity of the reaction furnace can be avoided.

If required, the non-operating mechanical conveyors according to the invention can be very well supplemented by a conveying path which is based on conveying air. For several reasons - back pressure, lack of space, burning behavior - it is most advantageous if the cross-sectional area of the designated as lance 6 tube, which leads through the furnace wall 7.1 into the furnace chamber 7, is as small as possible. Thus, there is a much higher speed of the moving granular material required there compared to the other production line. Therefore, and also for reasons of space and for the reasons prevailing in such areas heat, it is advantageous in such lances 6 at least not by means of mechanical conveyor alone to move, but at least supported by conveying air.

In the examples according to Fig. 1 and Fig. 2 the conveying air is that which is supplied by the pumps 21 and 22 to the conveyor train and ultimately flows through the lance 6 to the pressure level p2 in the furnace chamber 7. Due to the space conditions, the high furnace pressure and the high temperature prevailing at the point of introduction, this type of introduction is particularly advantageous for the supply of fuel or reaction material into the pressure zone of a shaft furnace for crude steel production.

In order to avoid clogging at the entrance area into the lance 6, a screw conveyor 5, which is adapted in diameter to the inner diameter of the lance 6, used to material from the conveying area with a larger cross-sectional area in the lance, which has a comparatively very small flow cross-section to contribute. Due to their small diameter, the screw conveyor 5 must rotate relatively quickly. The at high screw speeds due to centrifugal problematic filling the helical interspaces with the material to be delivered is substantially improved by the flow of air from the pressure range p1 in the delivery channel in the pressure range p2 in the oven. If the lance 6 is just straight, needs to be promoted by means of the screw conveyor 5 only in its initial region into it. Due to the very fast rotating screw conveyor 5, the material is loosened strengthened whereby the burning behavior is improved.

Instead of the screw conveyor 5 can also be a blast wheel 15 as a pressure-free working mechanical conveyor ( Fig. 3 ) be used. To such, motor-driven fast-rotating, equipped with blades or similar on the circumference protruding parts wheel, the flow of material to be conveyed is introduced and divided by the blades or similar parts into small, separate batches and thrown by centrifugal force.

Because the transport of material from the reservoir 2 to the point of introduction at the furnace takes place predominantly by mechanical conveying means and not by pressure or compressed air as in previously known constructions, the conveying function becomes much more independent of the exact properties of the material to be conveyed.

Because of that Fig. 1 and Fig. 2 only in the last part of the conveyor line with the aid of conveying air conveyed forward, the amount of required conveying air in relation to the amount of material to be conveyed, if necessary, can also be set very low. Thus, the control of the reaction in the furnace is less influenced by the delivery mechanism compared to a more based on conveying air material transport control.

The embodiment according to Fig. 2 differs from that according to Fig. 1 in that a flexible screw conveyor 13 is arranged in front of the last screw conveyor 5, which conveys support by an air flow into the lance 6. This consists of a flexible shaftless auger and a surrounding hose. Such an embodiment is advantageous over a rigid embodiment, since it allows the maintenance work often required at the point of introduction into the furnace to be carried out more rapidly.

In Fig. 2 is symbolized by the dashed lines indicated compressed air line 24 that the conveying air can be fed either directly to the lance the conveyor line, or even at the beginning of the flexible section of the conveyor line. Under certain circumstances, the flexible screw section can also be realized by a hose alone, without conveyor screw disposed therein.

In Fig. 3 a variant of the invention is outlined, in which the supply from the outside with the pressure p0 in the delivery area p1 is not by means of a reservoir 2 to be filled discontinuously, but continuously or quasi-continuously by means of a sufficiently pressure-tight pump 12. Pumps for such applications are available, for example, under the name solid piston pump. From the pump 12, the material to be delivered passes through a hose to a trained in this example as a blast wheel 15, non-pressure working mechanical conveyor. This, motor driven fast rotating, equipped with blades or similar on the circumference protruding parts wheel divides the optionally formed by the pressure of the pump 12 strand of material back into small, separate batches and hurls them into the lance 6, through which they in enter the oven room 7. The movement of the material into and through the lance 6 is in turn assisted by an air flow which can be generated by pressing air or gas into the conveyor string before starting the lance 6 by means of a pump 27. Of course, further mechanical conveyors could be installed between the pump and the point of introduction to the furnace.

In Fig. 4 is illustrated that it is not excluded in that conveyor line, which is closed by the outside air to promote by means of partial sections 8 material also by means of conveying air. Especially with very wide conveyor lines and uncomplicated materials that can be quite useful. Preferably, for branch-free and straight sections can be a pneumatic promotion, so set up a promotion means of conveying air. So that not too much air is injected, as in Fig. 4 sketched conveying air after the end of such routes 8 are sucked off again by means of a pump 26.

Especially when the supply into the furnace chamber can also take place over a larger cross-sectional area and if there are no very high temperatures in the part of the furnace chamber adjoining the supply region, the introduction of the material into the furnace chamber can also take place without conveying air.

The inventive method and apparatus according to the invention are particularly advantageous for the introduction of granular, dry or wet waste and residues applicable in ovens, as exactly these substances or mixtures are subject in their consistency strong, often difficult to predict fluctuations of those physical properties "Flowability" and "eligibility" influence and because the inventive method and the device of the invention extremely robust against such fluctuations works.

On furnaces in which the inventive method and the apparatus according to the invention are particularly advantageous applicable, furnaces for cement production and blast furnaces are particularly important for the crude steel production. In both furnaces, waste and residues can be burned profitably and environmentally friendly with the additional effect of saving fossil fuels. By the method according to the invention and by the device according to the invention more and more different waste and residues can be supplied to this use under economic conditions. In the particularly difficult conditions of blast furnaces, the robustness of the function of the method according to the invention or of the device according to the invention is particularly effective.

It is advantageous to provide an inert atmosphere, at least in that region of the cavity of the conveying path which is closed off from the outside air and which is remote from the lance 6 and in which it is mechanically conveyed without pressure. This makes it very easy to prevent fires and explosions in the production line. For example, by means of the pump 21 according to Fig. 1 and Fig. 2 continuously supplied with a suitable amount of nitrogen or CO2 or air with reduced oxygen content in the reservoir 2 and thus in the feed train. In addition, if you need a larger amount of conveying gas per time or a different delivery gas for the lance 6, you can add this by the additional pump 22, which selectively pumps into the end of the conveyor line, in addition.

In many applications, it is necessary to mix the material to be conveyed into the reaction furnace from different individual components together and / or to bring it into a suitable state by mixing or stirring or to keep it in a condition capable of being conveyed. Danger of ignition and explosion that may occur in such mixing or stirring operations, is elegantly avoided when this mixing or stirring is performed in the reservoir 2 and when the reservoir 2 is filled in said manner with an inert atmosphere. The storage container 2 may itself be designed as a rotating, correspondingly sealed against outside air, possibly under overpressure drum mixer and / or include a stirrer.

Claims (15)

1. A method of conveying conveyable materials to a reaction oven via a hollow space which is sealed pressure-tight against the external air, which hollow space opens out into the oven space via a connecting tube, whereby the materials (1) are conveyed from the sealed hollow space into the oven space (7) via a connecting tube in the form of a lance (6), having a reduced cross sectional area with respect to the upstream conveying stretch; characterised in that a stream of air or gas flows into the oven space (7) from the region of the sealed hollow space disposed upstream from the lance; and in that said stream is conveyed into the receiving region of the lance by a pressurelessly operating mechanical conveying means (5, 15).
2. A method according to claim 1; characterised in that the conveying into the receiving region of the lance (6) is accomplished by means of a shaft-less conveying screw (5).
3. A method according to one of the preceding claims; characterised in that the tip of a pointed hollow body extends from the side of the pressurelessly operating mechanical conveying means to the receiving region of the lance; and in that air or gas streams out in the region of the tip of said hollow body, from one or more openings, which air or gas is at a higher pressure in said hollow body than the gas pressure in the oven space (7).
4. A method according to one of the preceding claims; characterised in that the material is brought into the aforesaid pressure-tight sealed hollow space via a liquid lock and a supply container (2) the inner space of which, in the operating state, is connected with the said hollow space which is sealed pressure-tight with respect to the external air, and is conveyed from there into at least one segment of the path which segment is distant from the supply container and from the oven, by means of at least one pressurelessly operating mechanical conveying means (3, 13).
5. A method according to one of the preceding claims; characterised in that thereby wastes and/or residual materials are introduced to a reaction oven.
6. A method according to claim 5; characterised in that thereby material is conveyed into the pressure zone of a blast furnace, for raw steel production.
7. A device for conveying conveyable materials to a reaction oven via a hollow space which is sealed pressure-tight with respect to the external air and which opens out into the oven space via a connecting tube, wherein the materials (1) from the sealed hollow space are conveyed into the oven space (7) via a connecting tube in the form of a lance (6), wherewith the lance has a cross sectional area which is reduced with respect to the upstream conveying stretch; characterised in that a stream of air or gas flows into the oven space from the region of the sealed hollow space disposed upstream from the lance; and in that said stream is conveyed into the receiving region of the lance by a pressurelessly operating mechanical conveying means (5, 15) disposed in the receiving region of the lance (6).
8. A device according to claim 7; characterised in that a conveying screw (5) is disposed in the receiving region of the lance (6).
9. A device according to claim 8; characterised in that the conveying screw (5) is shaft-less.
10. A device according to one of claims 7-9; characterised in that the device comprises a liquid lock for the materials and a storage container, wherewith the storage container is connected to the sealed hollow space, in the operating state, and wherewith, in at least one segment of said hollow space which segment is distant from the supply container and from the oven (7), a pressurelessly operating mechanical conveyer (3, 13) is disposed.
11. A device according to one of claims 7-10; characterised in that the hollow space which is sealed pressure-tight with respect to the external air is filled with inert gas.
12. A device according to claim 11; characterised in that the hollow space which is sealed pressure-tight with respect to the external air is comprised of a supply container (2) in the form of a mixer.
13. A device according to one of claims 7-12; characterised in that from the side of the pressurelessly operating mechanical conveyor (5, 15), the tip of a pointed hollow body extends into the accepting region of the lance (6); in that the said tip is provided with at least one opening; and in that a gas pressure prevails in the pointed hollow body which is greater than the gas pressure in the oven space (7).
14. A device according to one of claims 7-13; characterised in that the conveyed materials (1) comprise wastes and/or residual materials, which are conveyed to a reaction oven.
15. A device according to claim 14; characterised in that the lance (6) opens out into the pressure zone of a blast furnace for raw steel production.

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