Method For Reducing Molten Raw Materials, And Device For Carrying Out Said Method

Abstract

A method for reducing molten raw materials, includes placing the raw materials, in a solid or molten state, on an inductively heated bed with coke pieces. The reduced melt that runs off the coke bed is collected and the waste gases are discharged. A coke bed is inwardly limited by a tube-shaped element through which the reaction gases are drawn off via a plurality of draw-off openings in the tube-shaped element. The corresponding device has a reactor for a bed with coke pieces and an induction heater with at least one induction coil. The reactor has a loading opening and a discharge opening for the treated melt. The coke bed is ring-shaped around a tube-shaped element. The material of the tube-shaped element allows inductive coupling to the induction field of the induction coil and it has draw-off openings for drawing off reaction gases from the coke bed.

Claims

1-15. (canceled)

16. A method for reducing molten raw materials, the method comprising: providing a coke bed with coke pieces, the bed being inwardly delimited by a pipe-shaped element; placing the raw materials in a solid or molten state on the coke bed; heating the coke bed inductively at least partially; collecting the reduced melt that runs off the coke bed; and heating the pipe-shaped element and discharging the reaction gases from the coke bed via a plurality of exhaust vents formed in the pipe-shaped element.

17. The method according to claim 16, wherein the pipe-shaped element is adapted to the geometry of the coke bed.

18. The method according to claim 16, wherein the pipe-shaped element has a round or rectangular cross-section or a combination of both.

19. The method according to claim 16, wherein the pipe-shaped element is an electrically conductive, high temperature-resistant body that is gas-permeable and/or provided with bores.

20. The method according to claim 16, wherein the pipe-shaped element is heated inductively.

21. The method according to claim 16, wherein the induction heater provided for the induction heating of the coke bed and the pipe-shaped element is operated alternately or simultaneously with alternating current of different frequencies.

22. The method according to claim 21, which comprises using alternating current of at least a first and second frequency.

23. The method according to claim 16, wherein the exhaust vents pass through the wall of the pipe-shaped element and open inside the pipe-shaped element.

24. The method according to claim 16, wherein a reducing agent is blown or suctioned into the coke bed.

25. A device for reducing molten raw materials, the device comprising: a reactor for receiving a bed of coke pieces and an induction heater having at least one induction coil for the induction heating of the coke bed; said reactor being formed with a feed opening for the solid and molten raw materials and a tap hole for the processed melt; said reactor being configured to receive a coke bed with a ring-shaped cross section that is delimited internally by a pipe-shaped reactor element; said pipe-shaped element being formed of a material suitable for inductive coupling with an induction field of said induction coil, in particular graphite, and having a plurality of exhaust vents for discharging the reaction gases from the coke bed.

26. The device according to claim 25, configured for performing a method according to claim 16.

27. The device according to claim 25, wherein said pipe-shaped element is formed of graphite.

28. The device according to claim 25, wherein a voltage supply of said induction heater comprises at least one frequency inverter or frequency generator with a control unit, and wherein said control unit is configured for operating said induction heater alternately or simultaneously with alternating current of different frequencies.

29. The device according to claim 28, wherein said control unit is configured to operate said induction heater with alternating current of at least a first and a second frequency.

30. The device according to claim 25, wherein said exhaust vents pass through a wall of said pipe-shaped element and open into an exhaust duct arranged or provided on the inside of the pipe-shaped element.

31. The device according to claim 30, wherein said exhaust vents are arranged running diagonally upwards in a direction of the exhaust duct.

32. The device according to claim 30, wherein said exhaust vents have a first area with a first flow cross section and an adjacent second area that has a smaller flow cross section compared to the first area.

Description

[0036] The invention is explained in more detail in the following with reference to the example embodiments shown in the drawings.

[0037] FIG. 1 shows a reactor according to the invention,

[0038] FIG. 2 a detailed view of a cross-section of the pipe-shaped element for venting the reaction gases and

[0039] FIG. 3 a possible example embodiment for a bore for the intake of gas into the pipe-shaped element.

[0040] The reactor according to the invention in FIG. 1 consists of one or more induction coils 1 that are guided around the reactor wall 2. The induction coils 1 and reactor wall 2 in this case preferably have a round, coordinated cross-section. Furthermore, preferably rectangular or combinations of round and rectangular cross-sections can be used. A pipe-shaped element and a bulk material of coke pieces 4 are set into the reactor wall 2 for discharging reaction gases 3. The geometry of the pipe-shaped element for discharging reaction gases 5 is preferably coordinated with the geometry of the reactor. Solid and/or molten substances can be introduced into the inductively heated reactor. The resulting reaction gases are then discharged via the pipe-shaped element to remove the reaction gases 5 from the bulk of coke pieces 4 by means of a pressure difference towards the exit of the gas discharge duct 3. The remaining molten substances, e.g. metal melt and/or slag can, in the simplest embodiment, be directly removed from the inside of the reactor and the bulk of coke pieces 4 via a tap hole 6.

[0041] FIG. 2 shows a possible cross-section of the pipe-shaped element for discharging reaction gases 5. Bores 7 are set into the pipe wall 8 of the pipe-shaped element to discharge reaction gases 5 from the bulk of coke pieces 4. The bores are preferably arranged diagonally in such a way that they run upwards from the outside to the inside of the pipe-shaped element for the discharge of the reaction gases 5. This minimises the entry of solid or molten substances from the reactor volume of the bulk of coke pieces 4 into the interior of the pipe 9. Another embodiment of the pipe-shaped element for discharging reaction gases 5 has a modular design. In this case, any number of individual segments consisting of bores 7 and segments of the pipe wall 8 can be arranged above one other, forming the pipe-shaped element to discharge reaction gases 5. An additional embodiment of the pipe-shaped element for discharging reaction gases 5 has a modular design such that several individual segments of the pipe-shaped element for discharging reaction gases 5 are introduced parallel to each other into the bulk of coke pieces 4. Preferably, the various pipe-shaped elements for discharging reaction gases 5 have bores 7 at different levels within the bulk of coke pieces 4. This allows the reactor to be optimised in such a way that different reaction gases at different points within the bulk of coke pieces 4 can be discharged separately. Thus, different reaction zones can be defined in the bulk of coke pieces 4, from which reaction gases can be discharged independently. The definition of the various reaction zones can, for example, occur by setting various temperatures, e.g. by targeted application of reaction partners from outside the reactor wall 2 through nozzles. Another embodiment is the introduction of a pipe-shaped element to discharge reaction gases 5 consisting of several separated volumes on the inside of the pipe 9. Bores holes for different reaction zones allow a defined and independent discharge of reaction gases from the bulk of coke pieces 4 into the separated volumes on the inside of the pipe 9.

[0042] FIG. 3 is a detailed view of a possible embodiment of a bore 7 in the pipe wall 8 of the pipe-shaped element for discharging reaction gases 5. The bore 7 is preferably arranged diagonally in such a way that it runs upwards from the outside to the inside of the pipe-shaped element for discharging reaction gases 5. In addition, the bore 7 is divided into 2 segments with different dimensions. The part of the bore leading towards the exterior part 10 faces the bulk of coke pieces 4. It has a larger volume compared to the interior part of the bore 11 that leads directly to the inside of the pipe 9. Due to the higher volume of the exterior part of the bore 10, the speed of the reaction gases suctioned from the bulk of coke pieces 4 is reduced and possible solid or molten particles that are still in the flow of the gas can sink down to the underside of the outer part of the bore 10 and there flow back into the bulk of coke pieces 4. Due to the reduction of the diameter on the inside of the bore 11 compared to the outer part of the bore 10, there is a higher gas speed in the inner part of the bore 11, and preferably a turbulent mixing of the reaction gas from the bulk of coke pieces 4. Any solid or molten particles that have not been deposited in the outer part of the bore 10 preferably combine into larger particles in the turbulent zone of the inner part of the bore 11, which are then separated preferably here at the lower part of the inner part of the bore 11 and from there can flow back into the bulk of coke pieces 4. The outer part of the bore 10 can preferably be designed to be consequently rotationally symmetrical around the pipe-shaped element for discharging reaction gases 5 while the inner parts of the bore 11 are introduced at selected positions and at selected numbers into the outer part of the bore 10.

LEGEND FOR THE FIGURES

[0043] 1 induction coil [0044] 2 reactor wall [0045] 3 discharge of reaction gases [0046] 4 packed bed [0047] 5 pipe-shaped element for venting reaction gases [0048] 6 tap hole [0049] 7 bores [0050] 8 pipe wall [0051] 9 pipe interior [0052] 10 exterior part of bore [0053] 11 interior part of bore