Rotary kiln seal system with cooling assembly

Abstract

The invention relates to a rotary kiln seal system and to a corresponding control unit. The rotary kiln seal system comprises a seal disc which is designed to be secured to the exterior of a rotary tube. The seal disc has a first product side in a first axial direction and an atmosphere side in a second axial direction. The rotary kiln seal system additionally comprises an annular housing which is arranged on the seal disc. The housing is equipped with a cooling assembly which is designed to cool the rotary kiln seal system.

Description

[0001] Rotary kiln sealing system with cooling arrangement

[0002] Description

[0003] The invention relates to a rotary kiln sealing system with cooling arrangement and an associated control unit.

[0004] Rotary kilns are rotating cylindrical kilns for continuous processes in process engineering and are used, for example, in cement production. The product side of a rotating kiln, where high temperatures exist, must be sealed from a stationary housing of the kiln and the atmosphere. Rotary kilns can have a diameter of several meters and reach internal temperatures of over 1000°C. The processes in the kiln often take place in the absence of oxygen. To increase efficiency or enable new processes, industry is placing increasing demands on the temperature resistance and sealing properties of the rotary kiln.

[0005] The object of the invention is to provide an improved rotary kiln sealing system with high temperature resistance and simple and cost-effective manufacture.

[0006] This object is achieved by a rotary kiln sealing system having the features of claim 1 and a control unit having the features of claim 13.

[0007] The rotary kiln sealing system according to the invention with the features of claim 1 comprises a sealing disc which is designed to be attached to an outer side of a rotary kiln. The sealing disc has a product side in a first axial direction and an atmosphere side in a second axial direction. Furthermore, the rotary kiln sealing system comprises an annular housing which is arranged on the sealing disc. A cooling arrangement which is designed to cool the rotary kiln sealing system is arranged on the housing. Thus, thanks to the cooling arrangement, the rotary kiln sealing system according to the invention enables use at high process temperatures in the rotary kiln of the rotary kiln. The controlled temperature of the rotary kiln sealing system can simultaneously ensure improved sealing properties of the rotary kiln sealing system.

[0008] The product side borders the product area of ​​the rotary kiln, while the atmosphere side borders the environment.

[0009] The housing is preferably arranged coaxially with the sealing disc, with the sealing disc being arranged radially floating on the housing. More preferably, the housing has a U-shaped cross-section in the circumferential direction, with the housing enclosing a radial end of the viewing disc.

[0010] The subclaims show further preferred developments of the invention.

[0011] The rotary kiln sealing system preferably comprises a first sealing ring and a second sealing ring, wherein the first sealing ring, the second sealing ring, the housing, and the sealing disc form an annular first chamber, and wherein the cooling arrangement has an inlet and an outlet which are arranged on the housing and are configured to convey a cooling fluid into and out of the first chamber. The sealing rings are preferably packing sealing rings made of a braided fabric impregnated with a lubricant. The first and second sealing rings are preferably arranged on the housing and are configured to contact the sealing disc. Thus, the sealing rings increase the sealing properties of the rotary kiln sealing system. By incorporating the inlet and the outlet into the housing to convey a cooling fluid into and out of the first chamber, the rotary kiln sealing system can be cooled efficiently and precisely.The cooling fluid can be a gas or a liquid. Preferably, the cooling fluid is a barrier gas, such as nitrogen, which prevents mass transfer between the product side and the atmosphere side, thus further improving the sealing properties of the rotary kiln sealing system. In particular, the first chamber has a higher pressure than the process side and / or the atmosphere side.

[0012] Further preferably, the inlet and outlet on the housing are arranged circumferentially offset by 180°. Thus, the cooling fluid can flow through two symmetrical paths on both sides from the inlet of the first chamber to the outlet of the first chamber, which increases the cooling performance.

[0013] The cooling arrangement preferably has more than one inlet and / or more than one outlet. Multiple inlets and / or outlets can improve the cooling fluid exchange of the rotary kiln sealing system and increase the cooling capacity. If the cooling fluid is a gas, the inlet is preferably arranged below a central axis of the rotary kiln and the outlet above the central axis. Heating reduces the density of the gas, and the gas rises. Thus, by arranging the inlet below the central axis and the outlet above the central axis, the cooling fluid exchange can be improved and the efficiency of the cooling arrangement can be increased.

[0014] If the cooling fluid is a liquid, the inlet is preferably located above a central axis of the rotary tube and the outlet below the central axis. Due to the high density of the liquid, it sinks downwards due to gravitational force and, after exiting the outlet, can be efficiently pumped back toward the inlet located above.

[0015] Further preferably, the first chamber is arranged at a radial end of the sealing disc. Thus, the first chamber is positioned centrally between the product side and the atmosphere side and can efficiently cool the rotary kiln sealing system.

[0016] According to a further preferred embodiment of the invention, the rotary kiln sealing system comprises a third sealing ring, wherein the third sealing ring, the second sealing ring, the housing and the sealing disk form an annular second chamber. The second chamber has at least one inlet and at least one outlet. Thus, the rotary kiln sealing system has two chambers which are designed to cool the rotary kiln sealing system. For example, there can be a negative pressure in the first chamber and an positive pressure in the second chamber, whereby the two chambers are designed to cool the rotary kiln sealing system and at the same time enable a barrier circuit which increases the sealing properties of the rotary kiln sealing system. Cooling fluids at different temperatures can also be introduced into the first and second chambers.

[0017] The rotary kiln sealing system further preferably comprises a fourth sealing ring, wherein the fourth sealing ring, the first sealing ring, the housing, and the sealing disc form an annular third chamber having at least one inlet and at least one outlet. The third chamber allows the sealing properties of the rotary kiln sealing system to be further improved, while simultaneously improving the cooling properties through individual control of the three channels.

[0018] Particularly preferably, the third chamber is arranged on the product side of the sealing disc and / or the second chamber is arranged on an atmosphere side of the sealing disc. Thus, each side of the sealing disc and the housing can be cooled, thereby reducing the risk of temperature gradients in the rotary kiln sealing system.

[0019] A sliding ring is preferably arranged in the second chamber and / or the third chamber. During operation, the sliding ring preferably slides on the sealing disc, forming a sealing gap between the sliding ring and the sealing disc, with the sliding ring not contacting the sealing disc. Furthermore, the sliding ring is harder than the sealing ring. Thus, the sliding ring can reduce the forces exerted by the sealing disc on the sealing rings and prevent the generation of additional heat due to friction between the sealing rings and the sealing disc.

[0020] Further preferably, the sliding ring is segmented along its circumference, with the inlet and outlet arranged circumferentially between the segments. This enables a uniform introduction of the cooling fluid into the second and / or third chamber with the sliding ring.

[0021] Furthermore, the invention comprises a control unit which is configured to control a cooling arrangement of a rotary kiln sealing system according to one of the preceding claims with a cooling fluid via at least one first fluid system in order to cool the rotary kiln sealing system.

[0022] Further details, advantages, and features of the present invention will become apparent from the following description of exemplary embodiments with reference to the drawings. It shows:

[0023] Fig. 1 is a schematic representation of a rotary kiln sealing system according to a preferred embodiment,

[0024] Fig. 2 is a schematic representation of a circumferentially segmented sliding ring, with three inlets and one outlet, according to the preferred embodiment, and

[0025] Fig. 3 is a schematic sectional view of the rotary kiln sealing system according to the preferred embodiment.

[0026] A rotary kiln sealing system 1 according to a preferred embodiment of the invention is described in detail below with reference to Figures 1 to 3.

[0027] Figure 1 shows a rotary kiln sealing system 1 with a sealing disc 20, which is attached to a rotary tube 21 via a fastening flange 22.

[0028] The rotary kiln sealing system 1 seals a product side 23 of a rotary kiln to an atmosphere side 24, wherein the product side 23 is located in a first axial direction R1 of the sealing disc 20 and the atmosphere side 24 is located in an opposite second axial direction R2 of the sealing disc 20.

[0029] The sealing disc 20 is aligned coaxially with a central axis X - X of the rotary tube 21. Preferably, the sealing disc 20 is made of a metal and has a constant thickness.

[0030] An annular housing 10 with a cooling arrangement 2 is arranged around the sealing disc 20, essentially coaxial with the central axis XX of the rotary tube 21. The housing 10 has a U-shaped cross-section that opens radially inward. The sealing disc 20 is arranged floatingly in the opening of the U-shaped cross-section, so that the sealing disc 20 is configured to rotate within the housing 10. The housing 10 is shown as a single piece, but can also be composed of multiple components.

[0031] The housing 10 is connected to a housing component 26 of the rotary kiln on the product side 23 via a compensator 25 to compensate for axial and radial movements of the rotary kiln 21, for example, due to thermal expansion. The compensator 25 is preferably a fabric compensator.

[0032] The mounting flange 22 is preferably welded to the rotary tube 21. Further preferably, the mounting flange 22 has bores for detachably connecting the sealing disc 20 to the mounting flange 22 via a screw connection, so that the sealing disc 20 can be easily replaced when worn.

[0033] On the atmosphere side 24 of the sealing disc 20, a second sealing ring 33, a third sealing ring 34, and a segmented slide ring 11 are arranged in recesses in the housing 10. The third sealing ring 34 is arranged radially inside the second sealing ring 33. Furthermore, the segmented slide ring 11 is arranged radially between the second sealing ring 33 and the third sealing ring 34. The second sealing ring 33, the third sealing ring 34, and the segmented slide ring 11 are designed to contact the sealing disc 20 on the atmosphere side 24. Thus, an annular second chamber 42 is formed between the second sealing ring 33, the housing 10, the third sealing ring 34, and the sealing disc 20, which is sealed to the outside by the second sealing ring 33 and the third sealing ring 34. The segmented slide ring 11 is arranged inside the second chamber 42.

[0034] A fourth sealing ring 31, a first sealing ring 32, and another circumferentially segmented sliding ring 11 are arranged within recesses in the housing 10 on the product side 23 of the sealing disc 20. The fourth sealing ring 31 is arranged radially inside the first sealing ring 32. Furthermore, the segmented sliding ring 11 is arranged radially between the fourth sealing ring 31 and the first sealing ring 32. The fourth sealing ring 31, the first sealing ring 32, and the segmented sliding ring 11 are designed to contact the sealing disc 20. Thus, an annular third chamber 41 is formed between the fourth sealing ring 31, the housing 10, the first sealing ring 32, and the sealing disc 20, which is sealed off from the outside by the fourth sealing ring 31 and the first sealing ring 32. The segmented sliding ring 11 is arranged inside the third chamber 41.

[0035] Furthermore, the first sealing ring 32, the second sealing ring 33, the housing 10 and the sealing disc 20 form an annular first chamber 43 at the radially outer end of the sealing disc 20. Thus, the product from the product side 23 must pass through the fourth sealing ring 31, the third chamber 41 with segmented slide ring 11, the first sealing ring 32, the first chamber 43, the second sealing ring 33, the second chamber 42 with segmented slide ring 11 and the third sealing ring 34 in order to reach the atmosphere side 24.

[0036] The cooling arrangement 2 on the housing 10 has at least one inlet 14 and one outlet 15 in the housing for the first chamber 43, the second chamber 42 and the third chamber 41.

[0037] Figure 1 shows the inlet 14 on the housing 10 leading to the first chamber 43. The inlet 14 is centrally located at a radial end of the housing 10 and is configured to convey a cooling fluid into the first chamber 43. At least one outlet 15 is arranged circumferentially on the housing 10, which outlet is preferably offset by 180° around the central axis X-X from the inlet 14.

[0038] On the product side 23 of the housing 10, an outlet 15 is shown in Figure 1, which is placed circumferentially between two segments 11a, 11b of the segmented sliding ring 11 and is designed to convey a cooling fluid out of the third chamber 41.

[0039] On the opposite side of the sealing disc 20, another inlet 14 to the second chamber 42 is located circumferentially between two segments of the segmented sliding ring 11 in the housing 10. The inlet 14 allows the cooling fluid to be conveyed into the second chamber 42.

[0040] On the periphery, one inlet 14 and one outlet 15 or a plurality of inlets 14 and / or outlets 15 can be positioned in the housing 10 per chamber 41, 42, 43. A plurality of inlets 14 and / or outlets 15 per chamber 41, 42, 43 enables a cooling arrangement 2, which can cool the rotary kiln sealing system 1 as needed.

[0041] The outlet 15 at the third chamber 41 is connected to a first fluid system F1, which is configured to supply the third chamber 41 with an individual cooling fluid having an individual pressure and / or individual temperature. The inlet 14 at the second chamber 42 is connected to a second fluid system F2, which is configured to supply the second chamber 42 with an individual cooling fluid having an individual pressure and / or individual temperature.

[0042] Furthermore, the inlet 14 at the first chamber 43 is connected to a third fluid system F3, which is configured to control the first chamber 43 with an individual cooling fluid with an individual pressure and / or individual temperature.

[0043] The fluid systems F1, F2, F3 are connected to a control unit S, which is designed to control the fluid systems F1, F2, F3 in such a way that the correct amount of cooling fluid with the correct chemical and physical properties is conveyed into or out of the chambers 41, 42, 43 in order to enable optimal cooling and sealing of the rotary kiln by the rotary kiln sealing system 1.

[0044] Figure 2 schematically shows the circumferentially segmented sliding ring 11 according to the preferred embodiment, which is arranged in the third chamber 41. The segmented sliding ring 11 is annular and divided into four equally sized segments, namely a first segment 11a, a second segment 11b, a third segment 11c, and a fourth segment 11d.

[0045] Three inlets 14 and one outlet 15 are arranged on the segmented seal ring 11. The inlets 14 and the outlet 15 are each circumferentially positioned in an intermediate region 18 between the segments 11a, 11b, 11c, 11d and are configured to convey a cooling fluid into or out of the third chamber 41 and the sealing gap of the segmented seal ring 11. Thus, inlets 14 or outlets 15 are arranged in all intermediate regions 18 located in the circumferential direction of the segmented seal ring 11. The larger number of inlets 14 than outlets 15 ensures that uniform cooling is achieved around the circumference.

[0046] In the housing 10, the segmented sliding ring 11 is arranged substantially coaxially to the central axis X - X of the rotary tube 21, wherein the rotary tube 21 is arranged in a radially floating manner in the housing 10 via the sealing disc 20.

[0047] The inlets 14 and the outlet 15 on the segmented sliding ring 11 in the third chamber 41 are each connected to the first fluid system F1, which is controlled by the control unit S in order to achieve a defined pressure and / or a defined temperature and / or a defined cooling fluid in the third chamber 41.

[0048] Figure 3 shows a schematic sectional view of the rotary kiln sealing system 1 perpendicular to the central axis X-X through the rotary kiln 21, the sealing disc 20, the first chamber 43, and the housing 10. The inlet 14, which is configured to introduce a cooling fluid into the first chamber 43, is arranged at the upper end of the housing 10. The cooling fluid flows downward in the first chamber 43 between the sealing disc 20 and the housing 10.

[0049] The outlet 15, which is configured to convey the cooling fluid out of the first chamber 43, is arranged on the housing at a circumferential offset of 180°. The inlet 14 and the outlet 15 are connected to the third fluid system F3, which is controlled by a control unit S. The third fluid system F3 is configured to achieve a defined pressure and / or a defined temperature and / or a defined cooling fluid in the first chamber 43. In addition to the above written description of the invention, reference is hereby explicitly made to the drawings of the invention in the figures for the purpose of supplementing its disclosure.

[0050] List of reference symbols

[0051] 1 rotary kiln sealing system

[0052] 2 Cooling arrangement

[0053] 10 housings

[0054] 11 sliding ring

[0055] 11a First Segment

[0056] 11b Second segment

[0057] 11c Third segment 11d Fourth segment

[0058] 14 Entrance

[0059] 15 Outlet

[0060] 18 Intermediate area

[0061] 20 sealing washer

[0062] 21 rotary kiln

[0063] 22 Mounting flange

[0064] 23 Product page

[0065] 24 Atmosphere page

[0066] 25 Compensator

[0067] 26 Housing component

[0068] 31 Fourth sealing ring

[0069] 32 First sealing ring

[0070] 33 Second sealing ring

[0071] 34 Third sealing ring

[0072] 41 Third Chamber

[0073] 42 Second Chamber

[0074] 43 First Chamber

[0075] F1 First fluid system

[0076] F2 Second fluid system

[0077] F3 Third fluid system

[0078] R1 First axial direction

[0079] R2 Second axial direction

[0080] S control unit

[0081] X - X center axis

Claims

Claims 1. Rotary kiln sealing system (1), comprising . a sealing disc (20) which is designed to be fastened to an outer side of a rotary tube (21), wherein the sealing disc (20) has a product side (23) in a first axial direction (R1) and an atmosphere side (24) in a second axial direction (R2), . an annular housing (10) which is arranged on the sealing disc (20), and . a cooling arrangement (2), . wherein the cooling arrangement (2) is arranged on the housing (10) and is designed to cool the rotary kiln sealing system (1).

2. Rotary kiln sealing system (1) according to claim 1, wherein the rotary kiln sealing system (1) comprises a first sealing ring (32) and a second sealing ring (33), wherein the first sealing ring (32), the second sealing ring (33), the housing (10) and the sealing disk (20) form an annular first chamber (43), and wherein the cooling arrangement (2) has an inlet (14) and an outlet (15) which are arranged on the housing (10) and are configured to convey a cooling fluid into and out of the first chamber (43).

3. Rotary kiln sealing system (1) according to claim 2, wherein the inlet (14) and the outlet (15) on the housing (10) are arranged offset by 180° on the circumference.

4. Rotary kiln sealing system (1) according to claim 2 or 3, wherein the cooling arrangement (2) has more than one inlet (14) and / or wherein the cooling arrangement (2) has more than one outlet (15).

5. Rotary kiln sealing system (1) according to one of claims 2 to 4, wherein the cooling fluid is a gas and wherein the inlet (14) is arranged below a central axis (X - X) of the rotary tube (21) and wherein the outlet (15) is arranged above the central axis (X - X).

6. Rotary kiln sealing system (1) according to one of claims 2 to 4, wherein the cooling fluid is a liquid and wherein the inlet (14) is arranged above a central axis (X - X) of the rotary tube (21) and wherein the outlet (15) is arranged below the central axis (X - X).

7. Rotary kiln sealing system (1) according to one of claims 2 to 6, wherein the first chamber (43) is arranged at a radial end of the sealing disc (20).

8. Rotary kiln sealing system (1) according to one of the preceding claims, wherein the rotary kiln sealing system (1) comprises a third sealing ring (34), wherein the third sealing ring (34), the second sealing ring (33), the housing (10) and the sealing disc (20) form an annular second chamber (42) which has at least one inlet (14) and at least one outlet (15).

9. Rotary kiln sealing system (1) according to one of the preceding claims, wherein the rotary kiln sealing system (1) comprises a fourth sealing ring (31), wherein the fourth sealing ring (31), the first sealing ring (32), the housing (10) and the sealing disc (20) form an annular third chamber (41) which has at least one inlet (14) and at least one outlet (15).

10. Rotary kiln sealing system (1) according to one of claims 8 or 9, wherein the third chamber (41) is arranged on the product side (23) of the sealing disc (20) and / or wherein the second chamber (42) is arranged on an atmosphere side (24) of the sealing disc (20).

11. Rotary kiln sealing system (1) according to one of claims 8 to 10, wherein a sliding ring (11) is arranged in the third chamber (41) and / or the second chamber (42).

12. Rotary kiln sealing system (1) according to claim 11, wherein the sliding ring (11) is segmented on the circumference and wherein the inlet (14) and the outlet (15) are arranged on the circumference between the segments.

13. Control unit (S) which is configured to control a cooling arrangement (2) of a rotary kiln sealing system (1) according to one of the preceding claims with a cooling fluid via at least one first fluid system (F1) in order to cool the rotary kiln sealing system (1).

Images