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DE-102024125247-B4 - Calcining system and method for the thermal treatment of a substance

DE102024125247B4DE 102024125247 B4DE102024125247 B4DE 102024125247B4DE-102024125247-B4

Abstract

Calcining system for the thermal treatment of a substance (12), comprising at least one conveying device (14) with a main extension axis (H); which have at least one support facility (14) - at least one heat treatment volume (18) heated by a heating device (16) during the heat treatment with a heating temperature (T_H) and a cooling volume (20) arranged below the heat treatment volume (18) with a cooling temperature (T_K), wherein during the heat treatment the heating temperature (T_H) is greater than the cooling temperature (T_K); - a receiving device (22) designed to receive the substance (12) and to convey it, at least indirectly, into the heat treatment volume (18); - a dispensing device (24) which is arranged along the main extension axis (H) away from the receiving device (22) and is designed to dispense the substance (12) from the conveying device (14) after the thermal treatment; - an endless belt device (26) with an upper section (28) and a lower section (30); wherein the upper section (28) is movable along the main extension axis (H) in a conveying direction (F) from a first section transfer device (32.1) to a second section transfer device (32.2) and wherein the upper section (28) is configured to convey the substance (12) received by the receiving device (22) and conveyed onto the upper section (28) for thermal treatment in the thermal treatment volume (18); wherein the lower section (30) is movable in the cooling volume (20) in a return direction (R) opposite to the conveying direction (F) from the second section transition device (32.2) to the first section transition device (32.1) in the cooling volume (20) in a manner corresponding to the upper section (28); - a housing system (34, 36, 38.1, 38.2, 40.1, 40.2) comprising an upper housing section (34), a lower housing section (36), at least two side housing sections (38.1, 38.2) and at least two end housing sections (40); wherein the at least one conveying device (14) has an enclosure (46) arranged on the upper housing section (34) and extending along the main extension axis (H) in order to substantially enclose the heat treatment volume (18) together with the upper section (28). wherein the housing (46) has a shorter length on the inside and/or outside than the upper housing section (34) transverse to the main extension axis (H).

Inventors

  • Reiner Furthmann
  • Michael Weihrauch

Assignees

  • AUMUND Fördertechnik GmbH

Dates

Publication Date
20260513
Application Date
20240904
Priority Date
20240105

Claims (18)

  1. Calcining system for the thermal treatment of a substance (12), comprising at least one conveying device (14) with a main extension axis (H); comprising at least one conveying device (14) - at least one thermal treatment volume (18) heated during the thermal treatment by a heating device (16) with a heating temperature (T_H) and a cooling volume (20) arranged below the thermal treatment volume (18) with a cooling temperature (T_K), wherein during the thermal treatment the heating temperature (T_H) is greater than the cooling temperature (T_K); - a receiving device (22) configured to receive the substance (12) and convey it at least indirectly into the thermal treatment volume (18); - a dispensing device (24) arranged along the main extension axis (H) from the receiving device (22) and configured to dispense the substance (12) from the conveying device (14) after the thermal treatment; - an endless belt device (26) with an upper section (28) and a lower section (30); the upper section (28) being movable along the main extension axis (H) in a conveying direction (F) from a first section transfer device (32.1) to a second section transfer device (32.2), and the upper section (28) being configured to convey the substance (12) received by the receiving device (22) and conveyed onto the upper section (28) to the thermal treatment in the thermal treatment volume (18); the lower section (30) being movable in the cooling volume (20) along the main extension axis (H) in a return direction (R) opposite to the conveying direction (F) from the second section transfer device (32.2) to the first section transfer device (32.1), corresponding to the upper section (28); - a housing system (34, 36, 38.1, 38.2, 40.1, 40.2) comprising an upper housing section (34), a lower housing section (36), at least two side housing sections (38.1, 38.2) and at least two end housing sections (40); wherein the at least one conveying device (14) has an enclosure (46) arranged on the upper housing section (34) and extending along the main extension axis (H) to substantially enclose the heat treatment volume (18) together with the upper section (28), whereby the enclosure (46) has a shorter length on the inside and/or outside transversely to the main extension axis (H) than the upper housing section (34).
  2. Calcining system according Claim 1 , wherein the endless belt device (26) is essentially closed during the heat treatment, wherein the endless belt device (26) is preferably designed as a substance carrier (58) composed of segments (58.1) which are arranged successively without gaps to each other, particularly preferably overlapping, during the heat treatment; wherein the calcining system (10) has a substance mixing system (68, 70, 72) configured to mix the substance (12).
  3. Calcining system according Claim 1 or 2 , wherein the upper housing section (34), the lower housing section (36) and the two side housing sections (38.1, 38.2) form a substantially closed, in particular rectangular, profile in cross-section with respect to the main extension axis (H); wherein the conveying device (14) preferably has at least one air sealing means (41), in particular one or more rotary valves, wherein the at least one air sealing means (41) is configured to thermally insulate the receiving device (22) and/or the discharge device (24), in particular adjustable, from its surroundings; and/or wherein the heat treatment volume (18) preferably borders the upper housing section (34) and/or the cooling volume (20) borders the lower housing section (36).
  4. Calcining system according to at least one of the preceding claims, whereby the at least one conveying device (14) between the heat treatment volume (18) and the cooling volume (20) along the main extension axis (H) comprises at least one, in particular substantially continuous, thermal separation layer system (42); whereby the thermal separation layer system (42) is preferably formed at least by the upper section (28) and/or by an insulating surface structure (44).
  5. Calcining system according to the preceding claim, wherein the insulating surface structure (44) extends along the main extension axis (H) and transversely to the main extension axis (H) is essentially configured as a plane, arc, or triangular arc shape with a projection vertex (PSP); wherein the triangular arc shape is preferably configured such that the projection vertex (PSP) is oriented towards the upper housing section (34); and/or wherein the insulating surface structure (44) is preferably configured such that it extends into the two side housing sections (38.1, 38.2) or into the lower housing section (38.1, 38.2). housing section (36) opens to essentially enclose the cooling volume (20) together with the lower housing section (36).
  6. Calcining system according to at least one of the preceding claims, wherein the heating device (16) is arranged in the housing (46), particularly preferably on the inside at the top.
  7. Calcining system according to at least one of the preceding claims, wherein the at least one conveying device (14) has an intermediate volume (48) with an intermediate temperature (T_Z) between the upper heat treatment volume (18) and the lower cooling volume (20), wherein the intermediate temperature (T_Z) during the heat treatment is a value between the heating temperature (T_H) and the cooling temperature (T_K); wherein the at least one conveying device (14) has at least a first and a second volume separation device, wherein the first volume separation device separates the upper heat treatment volume (18) from the intermediate volume (48) and wherein the second volume separation device separates the lower cooling volume (20) from the intermediate volume (48); wherein the calcining system (10) is particularly preferably a calcining system (10) according to at least one of the Claims 4 until 6 is, and wherein the thermal separation layer system (42) particularly preferably comprises the at least two volume separation devices, wherein the upper section (28) is particularly preferably the first volume separation device and the insulating surface structure (44) is the second volume separation device.
  8. Calcining system according to at least one of the preceding claims, where the endless belt assembly (26) comprises: - a support structure (50) which is supported at least indirectly, for example via crossbeams (52), on the housing system (34, 36, 38.1, 38.2, 40.1, 40.2), in particular on both side housing sections (38.1, 38.2); - a support structure (54) with endless belt movement means (56), preferably with rollers (56.1) and/or tension means (56.2), particularly preferably chain means, wherein the endless belt movement means (56) are configured to move the support structure (54) along the support structure (50); - a substance carrier (58) which is configured to convey the substance (12) for heat treatment in the heat treatment volume (18) and which is connected to the support structure (54), whereby the substance carrier (58) is preferably composed of segments (58.1) which are arranged successively without gaps to each other, particularly preferably overlapping, during the heat treatment.
  9. Calcining system according to the preceding claim, whereby the substance carrier (58) has at least one segment (58.1) with a substance receiving form, wherein in particular the substance receiving form is essentially U-shaped; the substance receiving form comprising - a horizontally extending carrier platform (60) with two lateral longitudinal edges (57) parallel to the main extension axis (H), whereby the carrier platform (60) has successive steps (59), preferably at least one step (59) per segment (58.1), whereby each step (59) extends horizontally, substantially transversely to the main extension axis (H), whereby each segment (58.1) with a step (59) preferably has an upper height level (59.1) and a lower height level (59.2), wherein the upper height level (59.1) is arranged at the front in the conveying direction (F); - two vertically extending vertical planks (62.1, 62.2) each arranged on one of the two longitudinal edges (57), whereby the support platform (60) has successive projections (61), preferably at least one projection (61) per vertical plank (62.1, 62.2) of each segment (58.1), whereby each projection (61) extends horizontally substantially transversely to the principal extension axis (H).
  10. Calcining system according to one of the Claims 1 until 7 and according to the aforementioned claim, wherein the housing (46) is designed to open towards the substance carrier (58) and has a receiving form corresponding with the vertical planks (62.1, 62.2) with two vertical webs (64.1, 64.2), wherein preferably the vertical planks (62.1, 62.2) and the vertical webs (64.1, 64.2) are designed such that their horizontal distance is selected so that they do not touch each other during the heat treatment and gap-related heat loss is as low as possible; and/or wherein preferably the vertical planks (62.1, 62.2) and the vertical webs (64.1, 64.2) are arranged substantially parallel to each other.
  11. Calcining system according to at least one of the Claims 8 until 10 , wherein the endless belt motion means (56) are arranged vertically below the heat treatment volume (18) and horizontally outwards transversely to the main extension axis (H) by a horizontal distance (HA) to the heat treatment volume (18); wherein preferably the horizontal distance (HA) of the offset of each endless belt moving means (56) to the heat treatment volume (18) corresponds at least to the length (LB) of a corresponding endless belt moving means (56) in the longitudinal extension direction of the substance carrier segment (58.1), and/or wherein preferably the horizontal distance (HA) of the offset of each endless belt moving means (56) to the heat treatment volume (18) is at least 5 percent, preferably at least 7 percent and with particular preference at least 10 percent of the main horizontal extension of the segment (58.1) transverse to the main extension axis (H); and/or wherein preferably the horizontal distance (HA) of the offset of each endless belt motion means (56) to the heat treatment volume (18) is at most 30 percent, preferably at most 25 percent and with particular preference at most 15 percent of the main horizontal extent of the segment (58.1) transverse to the main extent axis (H).
  12. Calcining system according to at least one of the preceding claims, whereby the at least one conveying device (14) comprises a thermotreatment volume gas flow system (66, 66.1, 66.2) for gas exchange in the thermotreatment volume (18), the thermotreatment volume gas flow system (66, 66.1, 66.2) comprising at least one thermotreatment volume gas inlet regulator (66.1) and at least one thermotreatment volume gas outlet regulator (66.2), whereby the thermotreatment volume gas inlet regulator (66.1) is configured to feed gas, for example inert gas or combustion gas, into the thermotreatment volume (18), and whereby the thermotreatment volume gas outlet regulator (66.2) is configured to discharge gas, for example oxygen-containing or moisture-containing gas, from the thermotreatment volume (18); wherein preferably the thermotreatment volume gas flow system (66, 66.1, 66.2) is arranged at the enclosure (46) for gas exchange in the thermotreatment volume (18).
  13. Calcining system according to at least one of the preceding claims, wherein the at least one conveying device (14) comprises a cooling volume gas flow system (67, 67.1, 67.2) for gas exchange in the cooling volume (20), the cooling volume gas flow system (67, 67.1, 67.2) comprising at least one cooling volume gas inlet regulator (67.1) and at least one cooling volume gas outlet regulator (67.2), wherein the cooling volume gas inlet regulator (67.1) is configured to feed gas, for example inert gas or cooling gas with a defined cooling gas temperature, into the cooling volume (20), and wherein the cooling volume gas outlet regulator (67.2) is configured to discharge gas, for example inert gas or cooling gas with a defined cooling gas temperature, from the cooling volume (20); wherein preferably the calcining system (10) is a calcining system (10) according to at least one of the Claims 5 until 12 is, wherein the cooling volume gas flow system (67, 67.1, 67.2) is particularly preferably arranged on the lower housing section (36) or on one or both side housing sections (38.1, 38.2) for gas exchange in the cooling volume (20).
  14. Calcining system according to at least one of the preceding claims, wherein the volume of the heat treatment volume (18) is smaller than the volume of the cooling volume (20) and/or the volume of the intermediate volume (48).
  15. Calcining system according to at least one of the preceding claims, wherein the at least one conveying device (14) as a substance mixing system comprises at least one circulation system (68) for mixing the substance (12); wherein preferably the at least one circulation system (68) comprises at least one stationary ploughing means (72) relative to the housing system (34, 36, 38.1, 38.2, 40.1, 40.2), which is designed such that it circulates the substance (12) conveyed on the upper run (28) in the conveying direction (F); and/or wherein the at least one circulation system (68) preferably comprises at least one roller device (70) whose axis of rotation is arranged transversely to the main extension axis (H), wherein the circumferential speed of the at least one roller device (70) is particularly preferably about 10 percent, more preferably about 15 percent, more preferably about 20 percent, and most preferably about 25 percent greater than the conveying speed of the endless belt device (26), and/or wherein the conveying speed of the endless belt device (26) is preferably at least 0.03 m/s, more preferably at least 0.05 m/s and/or at most inclusive of 0.3 m/s, more preferably at most inclusive of 0.2 m/s, and most preferably at most inclusive of 0.1 m/s; and/or wherein the at least one roller device (70) preferably comprises at least one stirring rod assembly and/or at least one paddle assembly extending radially; and/or wherein preferably the at least one conveying device (14) has at least one homogenizing device (74) which is located in the conveying direction (F) after the at least one circulation system (68) is arranged, wherein the homogenization device (74) is in particular designed as a crossbeam structure, wherein the at least one homogenization device (74) is designed to homogenize the distribution of the substance (12) circulated by the circulation system (68) on the upper section (28).
  16. Calcining system according to at least one of the preceding claims, whereby the calcining system (10) comprises at least two or more successive conveying units (14) arranged in a cascade configuration as a substance mixing system, whereby the discharge unit (24) of the at least one preceding conveying unit (14) for vertical conveying of the substance (12) is preferably connected at least indirectly to the receiving unit (22) of the at least one subsequent conveying unit (14), for example via a chute construction (76), whereby the chute construction (76) is preferably designed to be substantially gap-free and/or airtight to the outside.
  17. Calcining system according to the preceding claim, whereby the cascade shape is configured such that the principal axis of extension (H) towards the horizon from above essentially forms an angle (α, alpha) of at least -5 degrees, preferably at least 0 degrees, particularly preferably at least 10 degrees, and most preferably at least 20 degrees; and/or whereby the cascade shape is configured such that the principal axis of extension (H) towards the horizon from above essentially forms an angle (α, alpha) of at most 40 degrees, preferably at most 30 degrees, particularly preferably at most 28 degrees, and most preferably at most 25 degrees.
  18. A method for the thermal treatment of a substance (12) using the calcining system (10) according to at least one of the preceding claims, the method comprising at least the following steps: - receiving (100) the substance (12) by means of the receiving device (22); - conveying the substance (12) on the upper section (28) along the main extension axis (H), wherein the substance (12) is conveyed at least partially through the heated thermal treatment volume (18) for thermal treatment, wherein the calcining system (10) preferably has at least the features of the Claim 15 exhibits such that at least a mixing of the substance (12) takes place by means of the at least one circulation system (68); - Dispensing (300) of the substance (12) by means of the dispensing device (24), wherein preferably the calcining system (10) has at least the features of the Claim 16 or 17 exhibits such that at least a mixing of the substance (12) by the vertical conveying of the substance (12), in particular essentially as free fall, takes place from the discharge device (24) of the at least one preceding conveying device (14) to the receiving device (22) of the at least one subsequent conveying device (14).

Description

Technical field The following describes a calcining system for the thermal treatment of a substance, especially clay. Furthermore, a method for the thermal treatment of a substance, in particular clay, using the aforementioned calcining system is described below. Technical background Calcining is a heat treatment process in the presence of air or oxygen, applied, for example, to ores and other solid substances to cause thermal decomposition, a phase transition, or the separation of a volatile component. Calcining systems with conveyor belts used for calcination can include, in particular, push grate conveyors. These feature, for example, an air-permeable belt surface, also called a grate, through which hot air from the heat treatment volume is drawn downwards through the substance lying on the belt surface, thereby calcining it. One advantage of this solution is the uniform heat transfer through the entire layer of substance lying on the belt surface, which allows for homogeneous calcination. The document CN 112361805 A This describes a zinc oxide calcining furnace that uses a chain conveyor. The furnace is equipped with a first and a second guide roller at the inner ends of the furnace body. A chain conveyor is stretched between these guide rollers. Gears on one side of the guide rollers are connected by a rack and pinion chain, which is driven by the motor. The motor drives the chain conveyor, which transports the material, thus enabling its heating and decomposition. On the other hand, the large amounts of dust generated by the airflow and suction are a disadvantage, as they later require complex cleaning processes using cyclones and filters. Furthermore, the air-permeable belt linings become clogged repeatedly, which can lead to operational disruptions or production losses. These downtimes result in financial losses. Additionally, sufficiently fine particles pass through the belt linings and must be laboriously removed as free-flowing material and reintroduced into the process. Finally, a significant amount of heat is extracted from the heat treatment volume, making it an energy-intensive process. Technical description Given this situation, the task is to provide an improved calcining system and an improved process for the thermal treatment of a substance. In particular, the dust load should be reduced, energy efficiency increased, and/or the free-flowing material problem avoided. The above problem is solved by the features of the independent main claims. Advantageous embodiments are specified in the dependent claims. Where technically feasible, the teachings of the dependent claims can be combined arbitrarily with the teachings of the main and dependent claims. In particular, the task is therefore solved by a calcination system for the thermal treatment of a substance, comprising at least one conveying facility with a main extension axis; which have at least one funding facility - at least one heat treatment volume heated during the heat treatment by a heating device, in particular from above, with a heating temperature and a cooling volume arranged below the heat treatment volume, in particular at least indirectly, with a cooling temperature, wherein the heating temperature is higher than the cooling temperature during the heat treatment; - a receiving device designed to receive the substance and convey it, at least indirectly, into the heat treatment volume; - a dispensing device which is arranged along the main extension axis away from the receiving device and is designed to dispense the substance from the conveying device after thermal treatment; - an endless belt device with an upper section and a lower section; wherein the upper section is movable along, i.e. parallel, the main axis of extension in a conveying direction from a first section transfer device to a second section transfer device, and wherein the upper section is configured to convey the substance received by the receiving device and conveyed onto the upper section for heat treatment in the heat treatment volume conveying; wherein the lower section is movable in the cooling volume along the main extension axis in a return direction opposite to the conveying direction from the second section transition device to the first section transition device, correlating with the upper section; - a housing system comprising an upper housing section, a lower housing section, two side housing sections and two end housing sections. The following sections explain advantageous aspects of the claimed solutions and subsequently describe preferred modified embodiments of the solutions. Explanations, particularly regarding advantages and definitions of features, are essentially descriptive and preferred, but not limiting, examples. If an explanation is limiting, this will be explicitly stated. In particular, calcination is synonymous with heat treatment, although this is not strictly binding. However, it can also be defined or equated in a binding manner.