Multi-section cooling lime shaft kiln
By dividing the lime vertical kiln chamber into low-temperature, medium-temperature and high-temperature zones, and using segmented cooling air, the problems of low CO2 concentration and uneven cooling of the flue gas are solved, and efficient cooling and production efficiency of lime are achieved.
Patent Information
- Application Number
- CN202421433684.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-21
- Publication Date
- 2025-08-01
- Estimated Expiration
- 2034-06-21
AI Technical Summary
In the existing lime production process, low flue gas CO2 concentration leads to high carbon capture costs, and indirect cooling methods are prone to reverse reaction of lime, uneven cooling and equipment wear, affecting production efficiency and maintenance costs.
A lime vertical kiln with multiple cooling stages is used to divide the lower part of the kiln chamber into low-temperature, medium-temperature and high-temperature zones, and primary and secondary cooling air is introduced respectively to avoid reverse reactions, and the cooling flow direction is optimized through the inclined secondary air nozzle and drainage device to improve cooling efficiency.
It realizes efficient cooling of lime, avoids reverse reactions, improves yield, reduces carbon capture costs, reduces equipment wear, and improves production continuity and efficiency.
Smart Images
Figure CN223176020U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a lime shaft kiln, in particular to a lime shaft kiln with multi-stage cooling, belonging to the technical field of lime production. Background Technique
[0002] Active lime is an important industrial raw material, which is widely used in many industries (such as the steel industry, calcium carbide industry, alumina, etc.) and has a huge demand. In the past decade, the lime production in China has been increasing continuously. In 2020, the domestic lime production reached 300 million tons, and the CO2 emissions generated reached more than 330 million tons, which is the key object of CO2 emission reduction and carbon capture in the industrial field.
[0003] Figure 5 The shown co-current regenerative double-chamber lime shaft kiln is the most advanced type of industrial lime production equipment and the mainstream kiln type at present. It adopts the double-chamber reversing regenerative technology and has the advantages of high system energy efficiency, uniform product roasting, and low pollution emissions compared with other kiln types such as rotary kilns and mechanized shaft kilns. However, the CO2 concentration in the tail-end flue gas generated by its current conventional lime production process is relatively low, generally below 20%. Since the carbon capture cost increases with the decrease in the carbon dioxide concentration in the capture source, its carbon capture cost is as high as more than 300 yuan / ton of carbon dioxide, resulting in most manufacturers directly discharging the tail gas into the atmosphere, causing great waste of resources and environmental pollution. Therefore, the too low tail-end CO2 concentration greatly restricts the large-scale application of carbon capture technology in lime kiln equipment.
[0004] In view of the above problems, the technical personnel in the industry proposed a carbon front enrichment technology, that is, to obtain high-concentration CO2 flue gas by reducing or eliminating other gas components in the flue gas, thereby greatly reducing the tail-end carbon capture cost and realizing near-zero emissions in lime production. The main technical feature of this method is to use recycled flue gas to replace cooling air to cool high-temperature lime, and at the same time use pure oxygen + recycled flue gas for calcination to obtain high-concentration CO2 flue gas. However, directly using high-concentration CO2 flue gas to cool high-temperature calcium oxide is likely to cause an inverse carbonization reaction between calcium oxide and CO2, regenerating calcium carbonate and reducing the quality and output of lime products.
[0005] At present, indirect cooling is usually adopted to avoid the reaction between the cooling gas and the high-temperature material. However, a large number of cooling pipes in the indirect cooling device are distributed inside the lime shaft kiln, which is likely to cause material accumulation, form a bridging effect, hinder the downward movement of the material, and disrupt the continuity of production. At the same time, indirect cooling is prone to uneven local heating, that is, the material close to the cooling pipe cools faster, while the cooling rate of the material farther away from the cooling pipe is slower, resulting in too high local temperature of the outlet material, or consuming more cooling resources to meet the requirements of all outlet material temperatures. In addition, the cooling pipes bear mechanical friction and thermal stress of the high-temperature material in the furnace, and are very likely to crack, bend and deform, etc., and need to be replaced frequently, resulting in forced interruption of production, reduced production efficiency and high maintenance costs. Content of the Utility Model
[0006] Aiming at the problems in the prior art that the CO2 concentration in the flue gas generated by the conventional lime production process is low, difficult to capture, the lime is prone to reverse reaction, and the existing lime cooling process has low efficiency and high maintenance costs, etc., the utility model provides a lime shaft kiln with multi-stage cooling, divides the lower part of the first kiln chamber into three temperature zones, and uses a secondary air duct to introduce secondary cooling air into the medium-temperature zone, while the primary cooling air enters from the bottom of the first kiln chamber, bypasses the medium-temperature zone and directly enters the high-temperature zone, preventing the primary cooling air from reacting reversely with the lime in the medium-temperature zone, and at the same time ensuring the cooling effect on the lime in the medium-temperature zone.
[0007] A lime shaft kiln with multi-stage cooling, the lime shaft kiln is a double-chamber lime shaft kiln, including a first kiln chamber and a second kiln chamber arranged in parallel, and the first kiln chamber and the second kiln chamber are connected by a connecting channel. The upper part of the first kiln chamber is a lime calcination zone, and the lower part is a multi-stage cooling zone. The multi-stage cooling zone is successively a low-temperature zone, a medium-temperature zone and a high-temperature zone from bottom to top. A material diversion plate is arranged in the medium-temperature zone of the multi-stage cooling zone. The material diversion plate includes an annular top plate, a cylindrical side plate and an annular bottom plate. The annular top plate is located in the high-temperature zone, and the outer ring end of the annular top plate is connected to the side wall of the high-temperature zone, and its inner ring end is connected to the upper end of the cylindrical side plate. The annular bottom plate is located in the low-temperature zone, and the outer ring end of the annular bottom plate is connected to the side wall of the low-temperature zone, and its inner ring end is connected to the lower end of the cylindrical side plate. The annular top plate, the cylindrical side plate, the annular bottom plate and the side wall of the multi-stage cooling zone together form an annular cavity. The bottom of the low-temperature zone is provided with a primary air inlet and a secondary air inlet pipe. The air outlet end of the secondary air inlet pipe extends into the low-temperature zone from the bottom and extends upward into the blanking channel formed by the cylindrical side plate. A secondary air outlet pipe is arranged on the cylindrical side plate. The air outlet end of the secondary air outlet pipe successively penetrates through the annular cavity and the side wall of the multi-stage cooling zone and then extends to the outside of the first kiln chamber. Primary air vent holes are arranged on the annular bottom plate. Primary air communication holes for communicating the annular cavity with the high-temperature zone are arranged on the annular top plate and / or the upper part of the cylindrical side plate.
[0008] Preferably, the upper end of the cylindrical side plate is arranged in the high-temperature area or at the junction of the high-temperature area and the medium-temperature area. The lower end of the cylindrical side plate is arranged in the low-temperature area or at the junction of the medium-temperature area and the low-temperature area.
[0009] Preferably, the upper end of the secondary air inlet pipe is arranged at the junction of the low-temperature area and the medium-temperature area or within the medium-temperature area. Preferably, secondary air nozzles are provided on the pipe body of the secondary air inlet pipe at the junction of the low-temperature area and the medium-temperature area and / or on the pipe body within the medium-temperature area.
[0010] Preferably, the secondary air nozzle has an inclined structure with the outer side being higher than the inner side, and the inclination angle is 30° to 60°, preferably 35° to 55°. Preferably, the air inlet of the secondary air outlet pipe is located obliquely above the secondary air nozzle.
[0011] Preferably, there are 2 to 12 secondary air nozzles and 2 to 12 secondary air outlet pipes in the lime shaft kiln, preferably 6 to 10 secondary air nozzles and 6 to 10 secondary air outlet pipes. Preferably, the number of secondary air nozzles is equal to the number of secondary air outlet pipes.
[0012] Preferably, the lime shaft kiln further includes a primary air diversion device, and the primary air diversion device is arranged in the material discharge channel at the junction of the medium-temperature area and the high-temperature area. The primary air diversion device includes a housing and a fan arranged inside the housing. The housing is a semi-closed structure with air inlet holes provided on the side wall, air outlet holes provided on the top wall, and no holes on the bottom wall. Preferably, the top wall of the housing is a conical structure. Preferably, the primary air diversion device is arranged on the top of the secondary air inlet pipe.
[0013] Preferably, the lime shaft kiln further includes a high-temperature air pipe. The primary air connection hole is arranged in the upper part of the cylindrical side plate. One end of the high-temperature air pipe is connected to the primary air connection hole, and the other end is connected to the air inlet hole on the side wall of the housing.
[0014] Preferably, there are 2 to 12 primary air connection holes in total on the cylindrical side plate, preferably 3 to 9 primary air connection holes in total.
[0015] Preferably, the number of high-temperature air pipes is equal to the number of air inlet holes on the side wall of the housing.
[0016] Preferably, the annular top plate has an inclined structure with the outer ring end being higher than the inner ring end. Preferably, the angle between the annular top plate and the horizontal plane is 30 to 75°, preferably 45 to 60°.
[0017] Preferably, a temperature monitoring device is provided in the low-temperature area and / or the medium-temperature area and / or the high-temperature area.
[0018] A air volume regulating valve is arranged in the secondary air inlet pipe.
[0019] In the present utility model, according to the test results of the weight curve during the cooling process of high-temperature CaO in a pure CO2 atmosphere, as Figure 6 shown, the obvious reaction between CaO and CO2 occurs only in the temperature range of about 720 - 850 °C in the furnace chamber. Based on this principle, the present utility model adopts a multi-stage cooling method to cool the lime.
[0020] In the present utility model, the lower part of the first furnace chamber is divided into three temperature zones. A primary air inlet and a secondary air inlet pipe are arranged at the bottom of the low-temperature zone. The primary air enters the first furnace chamber from the primary air inlet, first cools the lime in the low-temperature zone, and then enters the annular cavity through the primary air ventilation holes on the annular bottom plate, bypasses the medium-temperature zone, and directly enters the high-temperature zone from the primary air communication holes on the annular top plate to cool the lime in the high-temperature zone, avoiding the reverse reaction of the lime in the medium-temperature zone and reducing the yield. At the same time, it also has the function of CO2 enrichment. In addition, the secondary air inlet pipe is directly connected to the material discharge channel formed by the cylindrical side plates at the bottom of the low-temperature zone, and secondary air is introduced into the medium-temperature zone. Since the temperature of the secondary air is relatively low, it will not react reversely with the lime in the medium-temperature zone, and at the same time has a good cooling effect on the lime. The present utility model combines the primary air and the secondary air to fully cool the lime in the first furnace chamber and reduce or even prevent the occurrence of reverse reactions. Preferably, the positions of the upper and lower ends of the cylindrical side plates in the first furnace chamber are defined to prevent the primary air from entering the medium-temperature zone and further prevent the occurrence of reverse reactions.
[0021] In the present utility model, the upper end of the secondary air inlet pipe is arranged at the junction of the low-temperature zone and the medium-temperature zone or within the medium-temperature zone to introduce secondary air into the medium-temperature zone. Preferably, one end of the secondary air outlet pipe where the secondary air nozzle is opened is the outlet end of the secondary air inlet pipe, and through the secondary air outlet pipe on the cylindrical side plate, the secondary air cools the lime in the medium-temperature zone and then discharges from the medium-temperature zone to avoid the reverse reaction between the secondary air and the lime after the temperature of the secondary air further rises in the medium-temperature zone or the high-temperature zone.
[0022] In the present utility model, the secondary air nozzle is set to have a structure with the outer part higher and the inner part lower to ensure that the secondary air exchanges heat with the material in a reverse direction as much as possible and improve the heat exchange efficiency. Preferably, the secondary air outlet pipe is arranged obliquely above the secondary air outlet so that the secondary air can maintain a reverse flow vector with the downward speed direction of the lime. Further preferably, a plurality of secondary air outlets and secondary air outlet pipes are arranged in the lime shaft kiln so that the secondary air can completely cover the medium-temperature zone and improve the lime cooling efficiency and uniformity.
[0023] In the present utility model, a primary air diversion device is provided to divert the primary air from the annular cavity to the junction of the medium-temperature zone and the high-temperature zone, and then enter the bottom of the high-temperature zone to cool the lime in the high-temperature zone, better controlling the flow direction of the primary air and improving the cooling efficiency of the primary air on the lime. Preferably, the primary air diversion device is connected to the air-permeable holes on the side plate through a high-temperature air pipe to avoid introducing the secondary air in the feeding channel corresponding to the medium-temperature zone.
[0024] In the present utility model, the structure of the annular top plate is such that the outer ring end is higher than the inner ring end, so that when the lime falls on the annular top plate, it can slide or roll down smoothly, avoiding the phenomenon of material blockage in the first kiln chamber.
[0025] In the present utility model, temperature monitoring devices are arranged in each temperature range to monitor the temperature change of the lime in the kiln in real time. In addition, a air volume regulating valve can be arranged in the secondary air pipeline to change the air volume of the secondary air introduced in real time according to the change of the lime temperature in the kiln, realizing the full cooling of the lime.
[0026] In the present utility model, the feeding channel is a channel formed by surrounding with a cylindrical side plate for the lime to fall, generally located on the central axis of the first kiln chamber.
[0027] Compared with the prior art, the present utility model has the following beneficial effects:
[0028] 1. A multi-stage cooling lime shaft kiln provided by the present utility model divides the lower part of the first kiln chamber into three temperature ranges, and introduces the primary air and the secondary air in sections to cool the lime in multiple stages, avoiding the reverse reaction of the lime, ensuring the output of the lime, and at the same time fully cooling the lime.
[0029] 2. A multi-stage cooling lime shaft kiln provided by the present utility model is provided with a secondary air nozzle and a secondary air outlet pipeline, and the secondary air nozzle is set as an inclined structure to avoid the reverse reaction with the lime after the temperature of the secondary air further rises in the medium-temperature zone or the high-temperature zone. At the same time, the secondary air can completely cover the medium-temperature zone, and the secondary air can maintain a reverse flow vector with the downward speed direction of the lime.
[0030] 3. A multi-stage cooling lime shaft kiln provided by the present utility model uses a primary air diversion device to introduce the primary air from the annular cavity into the high-temperature zone, and at the same time uses a high-temperature air pipe to avoid inhaling the secondary air in the feeding channel corresponding to the medium-temperature zone, improving the cooling efficiency. BRIEF DESCRIPTION OF THE DRAWINGS
[0031] Figure 1 It is a schematic structural diagram of the first kiln chamber in a multi-stage cooling lime shaft kiln provided by the present utility model.
[0032] Figure 2Schematic diagram of the primary air flow direction at the junction of the medium-temperature zone and the high-temperature zone in a multi-stage cooling lime shaft kiln provided by the present utility model.
[0033] Figure 3 Top view of the secondary air inlet pipe and the secondary air outlet pipe in a multi-stage cooling lime shaft kiln provided by the present utility model.
[0034] Figure 4 Side view of the secondary air inlet pipe and the secondary air outlet pipe in a multi-stage cooling lime shaft kiln provided by the present utility model.
[0035] Figure 5 Schematic diagram of the structure of a double-chamber lime shaft kiln provided by the present utility model.
[0036] Figure 6 Test diagram of the temperature range for the reaction of CaO with CO2 in a pure CO2 atmosphere.
[0037] Reference numerals: A: First kiln chamber; A1: Lime calcination zone; A2: Multi-stage cooling zone; A21: Low-temperature zone; A22: Medium-temperature zone; A23: High-temperature zone; B: Second kiln chamber; C: Connecting channel; 1: Material diversion plate; 101: Ring-shaped top plate; 102: Cylindrical side plate; 103: Ring-shaped bottom plate; 2: Primary air inlet; 3: Secondary air inlet pipe; 301: Secondary air nozzle; 4: Secondary air outlet pipe; 5: Primary air diversion device; 501: Housing; 502: Fan; 6: High-temperature air pipe. Detailed implementation manners
[0038] The technical solutions of the present utility model will be illustrated by examples below. The scope of protection claimed by the present utility model includes but is not limited to the following embodiments.
[0039] A multi-stage cooling lime shaft kiln, which is a double-chamber lime shaft kiln, includes a first kiln chamber A and a second kiln chamber B arranged in parallel. The first kiln chamber A and the second kiln chamber B are connected by a connecting channel C. The upper part of the first kiln chamber A is a lime calcination area A1, and the lower part is a multi-stage cooling area A2. The multi-stage cooling area A2 is successively a low-temperature area A21, a medium-temperature area A22, and a high-temperature area A23 from bottom to top. A material diversion plate 1 is provided in the medium-temperature area A22 of the multi-stage cooling area. The material diversion plate 1 includes an annular top plate 101, a cylindrical side plate 102, and an annular bottom plate 103. The annular top plate 101 is located in the high-temperature area A23, and the outer ring end of the annular top plate 101 is connected to the side wall of the high-temperature area A23, and its inner ring end is connected to the upper end of the cylindrical side plate 102. The annular bottom plate 103 is located in the low-temperature area A21, and the outer ring end of the annular bottom plate 103 is connected to the side wall of the low-temperature area A21, and its inner ring end is connected to the lower end of the cylindrical side plate 102. An annular cavity is jointly formed between the annular top plate 101, the cylindrical side plate 102, the annular bottom plate 103 and the side wall of the multi-stage cooling area A2. A primary air inlet 2 and a secondary air inlet pipe 3 are provided at the bottom of the low-temperature area A21. The air outlet end of the secondary air inlet pipe 3 extends into the low-temperature area A21 from the bottom and extends upward into the material discharging channel formed by the cylindrical side plate 102. A secondary air outlet pipe 4 is provided on the cylindrical side plate 102. The air outlet end of the secondary air outlet pipe 4 successively penetrates through the annular cavity and the side wall of the multi-stage cooling area A2 and then extends to the outside of the first kiln chamber A. Primary air vent holes are provided on the annular bottom plate 103. Primary air communication holes for communicating the annular cavity with the high-temperature area A23 are provided on the annular top plate 101 and / or the upper part of the cylindrical side plate 102.
[0040] Preferably, the upper end of the cylindrical side plate 102 is arranged in the high-temperature area A23 or at the junction of the high-temperature area A23 and the medium-temperature area A22. The lower end of the cylindrical side plate 102 is arranged in the low-temperature area A21 or at the junction of the medium-temperature area A22 and the low-temperature area A21.
[0041] Preferably, the upper end of the secondary air inlet pipe 3 is arranged at the junction of the low-temperature area A21 and the medium-temperature area A22 or in the medium-temperature area A22. Preferably, secondary air nozzles 301 are provided on the pipe body of the secondary air inlet pipe 3 at the junction of the low-temperature area A21 and the medium-temperature area A22 and / or on the pipe body in the medium-temperature area A22.
[0042] Preferably, the secondary air nozzles 301 are of an inclined structure with the outer part higher and the inner part lower, and the inclination angle is 30° to 60°, preferably 35° to 55°. Preferably, the air inlet of the secondary air outlet pipe 4 is located obliquely above the secondary air nozzles 301.
[0043] Preferably, there are 2 to 12 secondary air nozzles 301 and 2 to 12 secondary air outlet pipes 4 provided in the lime shaft kiln, preferably 6 to 10 secondary air nozzles 301 and 6 to 10 secondary air outlet pipes 4. Preferably, the number of the secondary air nozzles 301 is equal to the number of the secondary air outlet pipes 4.
[0044] Preferably, the lime shaft kiln further includes a primary air diversion device 5, and the primary air diversion device 5 is arranged in the blanking channel at the junction of the medium temperature zone A22 and the high temperature zone A23. The primary air diversion device 5 includes a housing 501 and a fan 502 arranged inside the housing 501. The housing 501 is a semi-closed structure with air inlet holes provided on the side wall, air outlet holes provided on the top wall, and no holes on the bottom wall. Preferably, the top wall of the housing 501 is a conical structure. Preferably, the primary air diversion device 5 is arranged on the top of the secondary air inlet pipe 3.
[0045] Preferably, the lime shaft kiln further includes a high temperature air pipe 6. The primary air connection hole is arranged at the upper part of the cylindrical side plate 102. One end of the high temperature air pipe 6 is connected to the primary air connection hole, and the other end is connected to the air inlet hole on the side wall of the housing 501.
[0046] Preferably, there are 2 to 12 primary air connection holes provided on the cylindrical side plate 102 in total, preferably 3 to 9 primary air connection holes provided in total.
[0047] Preferably, the number of the high temperature air pipes 6 is equal to the number of the air inlet holes on the side wall of the housing 501.
[0048] Preferably, the annular top plate 101 is an inclined structure with the outer ring end higher than the inner ring end. Preferably, the included angle between the annular top plate 101 and the horizontal plane is 30° to 75°, preferably 45° to 60°.
[0049] Preferably, a temperature monitoring device is arranged in the low temperature zone A21 and / or the medium temperature zone A22 and / or the high temperature zone A23.
[0050] Preferably, an air volume regulating valve is arranged in the secondary air inlet pipe 3. Example 1
[0051] A multi-stage cooling lime shaft kiln, which is a double-chamber lime shaft kiln, includes a first kiln chamber A and a second kiln chamber B arranged in parallel. The first kiln chamber A and the second kiln chamber B are connected by a connecting channel C. The upper part of the first kiln chamber A is a lime calcination area A1, and the lower part is a multi-stage cooling area A2. The multi-stage cooling area A2 is successively a low-temperature area A21, a medium-temperature area A22, and a high-temperature area A23 from bottom to top. A material diversion plate 1 is provided in the medium-temperature area A22 of the multi-stage cooling area. The material diversion plate 1 includes an annular top plate 101, a cylindrical side plate 102, and an annular bottom plate 103. The annular top plate 101 is located in the high-temperature area A23, and the outer ring end of the annular top plate 101 is connected to the side wall of the high-temperature area A23, and its inner ring end is connected to the upper end of the cylindrical side plate 102. The annular bottom plate 103 is located in the low-temperature area A21, and the outer ring end of the annular bottom plate 103 is connected to the side wall of the low-temperature area A21, and its inner ring end is connected to the lower end of the cylindrical side plate 102. An annular cavity is jointly formed between the annular top plate 101, the cylindrical side plate 102, the annular bottom plate 103 and the side wall of the multi-stage cooling area A2. A primary air inlet 2 and a secondary air inlet pipe 3 are provided at the bottom of the low-temperature area A21. The air outlet end of the secondary air inlet pipe 3 extends into the low-temperature area A21 from the bottom and extends upward into the material discharge channel formed by the cylindrical side plate 102. A secondary air outlet pipe 4 is provided on the cylindrical side plate 102. The air outlet end of the secondary air outlet pipe 4 successively penetrates through the annular cavity and the side wall of the multi-stage cooling area A2 and then extends to the outside of the first kiln chamber A. Primary air ventilation holes are provided on the annular bottom plate 103. Primary air communication holes for communicating the annular cavity with the high-temperature area A23 are provided on the annular top plate 101 and the upper part of the cylindrical side plate 102. Example 2
[0052] A multi-stage cooling lime shaft kiln, which is a double-chamber lime shaft kiln, includes a first kiln chamber A and a second kiln chamber B arranged in parallel. The first kiln chamber A and the second kiln chamber B are connected by a connecting channel C. The upper part of the first kiln chamber A is a lime calcination area A1, and the lower part is a multi-stage cooling area A2. The multi-stage cooling area A2 is successively a low-temperature area A21, a medium-temperature area A22, and a high-temperature area A23 from bottom to top. A material diversion plate 1 is provided in the medium-temperature area A22 of the multi-stage cooling area. The material diversion plate 1 includes an annular top plate 101, a cylindrical side plate 102, and an annular bottom plate 103. The annular top plate 101 is located in the high-temperature area A23, and the outer ring end of the annular top plate 101 is connected to the side wall of the high-temperature area A23, and its inner ring end is connected to the upper end of the cylindrical side plate 102. The annular bottom plate 103 is located in the low-temperature area A21, and the outer ring end of the annular bottom plate 103 is connected to the side wall of the low-temperature area A21, and its inner ring end is connected to the lower end of the cylindrical side plate 102. An annular cavity is jointly formed between the annular top plate 101, the cylindrical side plate 102, the annular bottom plate 103 and the side wall of the multi-stage cooling area A2. A primary air inlet 2 and a secondary air inlet pipe 3 are provided at the bottom of the low-temperature area A21. The air outlet end of the secondary air inlet pipe 3 extends into the low-temperature area A21 from the bottom and extends upward into the material discharge channel formed by the cylindrical side plate 102. A secondary air outlet pipe 4 is provided on the cylindrical side plate 102. The air outlet end of the secondary air outlet pipe 4 successively penetrates through the annular cavity and the side wall of the multi-stage cooling area A2 and then extends to the outside of the first kiln chamber A. Primary air vent holes are provided on the annular bottom plate 103. A primary air communication hole for communicating the annular cavity with the high-temperature area A23 is provided in the upper part of the cylindrical side plate 102. Example 3
[0053] Repeat Example 2, except that the upper end of the cylindrical side plate 102 is arranged at the junction of the high-temperature area A23 and the medium-temperature area A22. The lower end of the cylindrical side plate 102 is arranged at the junction of the medium-temperature area A22 and the low-temperature area A21. Example 4
[0054] Repeat Example 3, except that the upper end of the secondary air inlet pipe 3 is arranged at the junction of the low-temperature area A21 and the medium-temperature area A22. A secondary air nozzle 301 is provided on the pipe body of the secondary air inlet pipe 3 located in the medium-temperature area A22 at the junction of the low-temperature area A21 and the medium-temperature area A22. Example 5
[0055] Repeat Example 4, except that the secondary air nozzle 301 is an inclined structure with the outer part higher and the inner part lower, and the inclination angle is 45°. The air inlet of the secondary air outlet pipe 4 is located obliquely above the secondary air nozzle 301. Example 6
[0056] Repeat Example 5, except that there are a total of 8 secondary air nozzles 301 and 8 secondary air outlet pipes 4 in the lime shaft kiln. Example 7
[0057] Repeat Example 6, except that the lime shaft kiln further includes a primary air diversion device 5, and the primary air diversion device 5 is arranged in the blanking channel at the junction of the medium temperature zone A22 and the high temperature zone A23. The primary air diversion device 5 includes a housing 501 and a fan 502 arranged inside the housing 501. The housing 501 is a semi-closed structure with air inlet holes on the side wall, air outlet holes on the top wall, and no holes on the bottom wall. The top wall of the housing 501 is a conical structure. The primary air diversion device 5 is arranged on the top of the secondary air inlet pipe 3. Example 8
[0058] Repeat Example 7, except that the lime shaft kiln further includes a high temperature air pipe 6. The primary air communication hole is arranged in the upper part of the cylindrical side plate 102. One end of the high temperature air pipe 6 is connected to the primary air communication hole, and the other end is connected to the air inlet hole on the side wall of the housing 501. Example 9
[0059] Repeat Example 8, except that there are a total of 6 primary air communication holes on the cylindrical side plate 102. The number of the high temperature air pipes 6 is equal to the number of the air inlet holes on the side wall of the housing 501. Example 10
[0060] Repeat Example 9, except that the annular top plate 101 is an inclined structure with the outer ring end higher than the inner ring end. The included angle between the annular top plate 101 and the horizontal plane is 45°. Example 11
[0061] Repeat Example 2, except that temperature monitoring devices are arranged in the low temperature zone A21, the medium temperature zone A22, and the high temperature zone A23. A air volume regulating valve is arranged in the secondary air inlet pipe 3.
Claims
1. A lime shaft kiln with multi-stage cooling, characterized in that: This lime shaft kiln is a double-chamber lime shaft kiln, including a first kiln chamber (A) and a second kiln chamber (B) arranged in parallel. The first kiln chamber (A) and the second kiln chamber (B) are connected by a connecting channel (C). The upper part of the first kiln chamber (A) is a lime calcination area (A1), and the lower part is a multi-stage cooling area (A2). The multi-stage cooling area (A2) is successively a low-temperature area (A21), a medium-temperature area (A22), and a high-temperature area (A23) from bottom to top. A material diversion plate (1) is provided in the medium-temperature area (A22) of the multi-stage cooling area. The material diversion plate (1) includes an annular top plate (101), a cylindrical side plate (102), and an annular bottom plate (103). The annular top plate (101) is located in the high-temperature area (A23), and the outer ring end of the annular top plate (101) is connected to the side wall of the high-temperature area (A23), and its inner ring end is connected to the upper end of the cylindrical side plate (102). The annular bottom plate (103) is located in the low-temperature area (A21), and the outer ring end of the annular bottom plate (103) is connected to the side wall of the low-temperature area (A21), and its inner ring end is connected to the lower end of the cylindrical side plate (102). An annular cavity is jointly formed between the annular top plate (101), the cylindrical side plate (102), the annular bottom plate (103) and the side wall of the multi-stage cooling area (A2). A primary air inlet (2) and a secondary air inlet pipe (3) are provided at the bottom of the low-temperature area (A21). The air outlet end of the secondary air inlet pipe (3) extends into the low-temperature area (A21) from the bottom and extends upward into the material discharge channel formed by the cylindrical side plate (102). A secondary air outlet pipe (4) is provided on the cylindrical side plate (102). The air outlet end of the secondary air outlet pipe (4) successively penetrates through the annular cavity and the side wall of the multi-stage cooling area (A2) and then extends to the outside of the first kiln chamber (A). Primary air vent holes are provided on the annular bottom plate (103). Primary air communication holes for communicating the annular cavity with the high-temperature area (A23) are provided on the annular top plate (101) and / or the upper part of the cylindrical side plate (102).
2. The lime shaft kiln according to claim 1, characterized in that: The upper end of the cylindrical side plate (102) is arranged in the high-temperature area (A23) or at the junction of the high-temperature area (A23) and the medium-temperature area (A22); the lower end of the cylindrical side plate (102) is arranged in the low-temperature area (A21) or at the junction of the medium-temperature area (A22) and the low-temperature area (A21).
3. The lime shaft kiln according to claim 1, characterized in that: The upper end of the secondary air inlet pipe (3) is arranged at the junction of the low-temperature area (A21) and the medium-temperature area (A22) or in the medium-temperature area (A22).
4. The lime shaft kiln according to claim 3, characterized in that: Secondary air nozzles (3**01**) are provided on the pipe body of the secondary air inlet pipe (3) at the junction of the low-temperature area (A21) and the medium-temperature area (A22) and / or on the pipe body in the medium-temperature area (A22).
5. The lime shaft kiln according to claim 4, characterized in that: The secondary air nozzles (3**01**) are of an inclined structure with the outer part higher and the inner part lower, and the inclination angle is 30° - 60°.
6. The lime shaft kiln according to claim 5, characterized in that: The inclination angle is 35° - 55°.
7. The lime shaft kiln according to claim 3, characterized in that: The air inlet of the secondary air outlet pipe (4) is located obliquely above the secondary air nozzle (3**01**).
8. The lime shaft kiln according to any one of claims 3 to 7, characterized in that: A total of 2 - 12 secondary air nozzles (3**01**) and 2 - 12 secondary air outlet pipes (4) are provided in this lime shaft kiln.
9. The lime shaft kiln according to claim 8, wherein: There are 6 - 10 secondary air nozzles (301) and 6 - 10 secondary air outlet pipes (4) provided in the lime shaft kiln in total.
10. The lime shaft kiln according to claim 8, wherein: The number of the secondary air nozzles (301) is equal to the number of the secondary air outlet pipes (4).
11. The lime shaft kiln according to any one of claims 1-7, 9-10, characterized in that: The lime shaft kiln further includes a primary air diversion device (5), and the primary air diversion device (5) is arranged in the blanking channel at the junction of the medium - temperature zone (A22) and the high - temperature zone (A23); the primary air diversion device (5) includes a housing (501) and a fan (502) arranged inside the housing (501); the housing (501) is a semi - enclosed structure with air inlet holes on the side wall, air outlet holes on the top wall, and no holes on the bottom wall.
12. The lime shaft kiln according to claim 11, characterized in that: The top wall of the housing (501) is a conical structure.
13. The lime shaft kiln according to claim 11, characterized in that: The primary air diversion device (5) is arranged on the top of the secondary air inlet pipe (3).
14. The lime shaft kiln according to claim 11, characterized in that: The lime shaft kiln further includes a high - temperature air pipe (6); the primary air communication hole is arranged in the upper part of the cylindrical side plate (102), one end of the high - temperature air pipe (6) is connected to the primary air communication hole, and the other end is connected to the air inlet hole on the side wall of the housing (501).
15. The lime shaft kiln according to claim 14, characterized in that: There are 2 - 12 primary air communication holes provided on the cylindrical side plate (102) in total; and / or The number of the high - temperature air pipes (6) is equal to the number of the air inlet holes on the side wall of the housing (501).
16. The lime shaft kiln according to claim 15, characterized in that: There are 3 - 9 primary air communication holes provided on the cylindrical side plate (102) in total.
17. The lime shaft kiln according to claim 15, characterized in that: The annular top plate (101) is an inclined structure with the outer ring end higher than the inner ring end.
18. The lime shaft kiln according to claim 17, characterized in that: The included angle between the annular top plate (101) and the horizontal plane is 30 - 75°.
19. The lime shaft kiln according to claim 18, characterized in that: The included angle between the annular top plate (101) and the horizontal plane is 45 - 60°.
20. The lime shaft kiln according to any one of claims 1-7, 9-10, 12-19, characterized in that: A temperature monitoring device is arranged in the low - temperature zone (A21) and / or the medium - temperature zone (A22) and / or the high - temperature zone (A23); and / or An air volume regulating valve is arranged in the secondary air inlet pipe (3).
21. The lime shaft kiln according to claim 11, characterized in that: A temperature monitoring device is arranged in the low - temperature zone (A21) and / or the medium - temperature zone (A22) and / or the high - temperature zone (A23); and / or An air volume regulating valve is arranged in the secondary air inlet pipe (3).