Cyclone deashing air inlet system and method for cement kiln scr denitrification

Abstract

The application discloses a raking type soot blower cyclone slag removal air inlet system and method for a cement kiln SCR denitration, which is suitable for the working condition of a cement plant, can efficiently remove slag, automatically discharge slag on line, and does not interrupt soot blowing operation, and solves the technical problem that the existing raking type soot blower air inlet system of the cement plant has no effective slag removal structure, iron rust, welding slag and other impurities in the pipeline enter the rake pipe and block the rake holes, and then the catalyst of the SCR denitration system is blocked, the denitration efficiency is reduced, and the equipment operation and maintenance cost is increased.

Description

Technical Field

[0001] This invention relates to the field of denitrification systems in cement plants, and more particularly to a rake-type sootblower cyclone slag removal air intake system and method for SCR denitrification in cement kilns. Background Technology

[0002] In the cement clinker production process, to meet the requirements of ultra-low emission policies, most cement plants have installed SCR denitrification systems. Rake soot blowers, as the main equipment for catalyst cleaning in SCR denitrification systems, are widely used. Their function is to use compressed air to blow away ash accumulated on the catalyst surface and inside the orifices, ensuring smooth catalyst passage and maintaining stable operation of the denitrification system. Currently, the air intake systems of most rake soot blowers used in cement plants are directly connected to the main air supply pipe, without an effective slag removal and purification structure. During long-term operation, the air supply pipelines in cement plants will develop rust due to pipeline corrosion, and welding slag remaining from pipeline installation will also accumulate. These solid impurities will enter the rake tubes of the rake soot blower with the air supply, thus clogging the rake orifices. Clogged rake holes can lead to insufficient blowing pressure and uneven blowing in the rake soot blower, making it impossible to effectively remove dust from the catalyst surface. This results in blocked catalyst channels, reduced denitrification efficiency, and even excessive ammonia escape, failing to meet environmental emission requirements. Furthermore, to clean the clogged rake holes and catalyst, cement plants need to frequently shut down for maintenance, which not only increases operation and maintenance costs but also affects the continuous production of cement clinker, causing huge economic losses.

[0003] In the existing technology, some rake soot blowers have no filter screen at the air inlet or are equipped with a single filter screen for filtration. The single filter screen is easily clogged and needs to be replaced after the machine is stopped, which cannot meet the needs of continuous production in cement plants. At the same time, the single filter screen has no slag discharge structure, and the accumulation of impurities will cause excessive pressure loss, affecting the soot blowing effect.

[0004] Therefore, it is necessary to develop a new rake-type sootblower cyclone slag removal air inlet device to overcome the above problems. Summary of the Invention

[0005] Purpose of the invention: To address the shortcomings and defects of existing technologies, this invention provides a rake sootblower cyclone slag removal air intake system and method for SCR denitrification in cement kilns. It is suitable for cement plant operating conditions, can efficiently remove slag, automatically discharge slag online, and does not interrupt sootblowing operations. It solves the technical problem that existing rake sootblower air intake systems in cement plants lack an effective slag removal structure, leading to rust, welding slag, and other impurities entering the rake pipes and clogging the rake holes, which in turn causes catalyst blockage in the SCR denitrification system, reduced denitrification efficiency, and increased equipment operation and maintenance costs.

[0006] Technical Solution: The present invention provides a cyclone slag removal air intake system for a rake soot blower used in SCR denitrification of a cement kiln, characterized in that: it includes an air intake pipe, one end of which is connected to the rake soot blower for denitrification of the cement kiln, and the other end is tangentially connected to a cyclone separator through a first guide plate and a second guide plate, so that the air source rotates tangentially at high speed along the inner wall of the cyclone separator to form a centrifugal separation field; an air outlet pipe is provided at the top of the cyclone separator, and the air outlet pipe is sealed to the air intake end of the rake soot blower; a slag collection hopper is provided at the bottom of the cyclone separator, which is connected to the inside of the cyclone separator to collect the separated solid impurities; a spring counterweight flap is provided at the bottom of the cyclone separator, and the counterweight of the flap is adjusted by adjusting the spring force to achieve the dual functions of slag discharge and air lock; the cyclone... The upper part of the air separator is equipped with a detachable stainless steel filter screen, and the middle part is equipped with guide vanes. The guide vanes are arranged corresponding to the tangential air inlet to stabilize the airflow field and improve the separation efficiency. The air inlet pipe and air outlet pipe of the cyclone separator are connected to pressure transmitter one and pressure transmitter two to monitor the pressure values ​​at the inlet and outlet of the cyclone separator, thereby calculating the pressure difference to determine whether the filter screen is blocked. The bottom of the slag collection hopper is equipped with an automatic slag discharge valve to control the discharge of impurities in the slag collection hopper. The automatic slag discharge valve, pressure transmitter one, and pressure transmitter two are respectively connected to the PLC controller of the control unit and linked with the central control DCS system of the control unit. According to the pressure difference value monitored by the transmitter, the automatic slag discharge valve is automatically controlled to start and stop, so as to realize automatic slag discharge.

[0007] The cyclone separator is equipped with a stainless steel filter screen at the top, an inlet valve on the inlet pipe, an outlet valve on the outlet pipe, a bypass valve on the bypass pipe, and a stainless steel filter screen on the bypass pipe. The inlet pipe is equipped with a guide plate and a guide plate, which work together with the guide vanes to prevent the separated solid impurities from flowing back into the inlet pipe and to guide the compressed air tangentially into the cyclone separator. The control unit includes a PLC controller and electrical switches.

[0008] The air inlet pipe, slag hopper, and cyclone separator are made of stainless steel with a thickness of 2-4 mm. The inner walls of the cyclone separator and slag hopper are coated with a high-temperature resistant anti-corrosion coating or ceramic patches with a coating thickness of 0.3-0.5 mm and made of polytetrafluoroethylene or ceramic. The diameter of the cyclone separator is 150-250 mm.

[0009] The angle between the first and second guide vanes and the air inlet pipe is 10-15°; the angle between the guide vanes and the shell is 20-30°, and the length of the guide vanes is equal or gradually increases along the direction of compressed air rotation to form an inner volute to improve the cyclone slag removal efficiency.

[0010] The stainless steel filter screen 1 and stainless steel filter screen 2 have a mesh size of 16 to 32 to prevent impurities larger than 1 mm from entering the rake tube. The filter screen edge is provided with a sealing groove to seal and connect with the inner wall of the cyclone separator.

[0011] The outlet valve, bypass valve, and inlet valve are pneumatically or electrically controlled to effectively achieve on / off control and transmit feedback signals to the PLC control system.

[0012] The upper end of the slag collection hopper is connected to the conical part of the cyclone separator. The slag collection hopper is equipped with a spring counterweight automatic flap slag discharge structure to facilitate the settling of solid impurities. The spring counterweight flap and spring are installed on the central shaft and fixed at both ends by nuts. The torque of the spring is adjusted by tightening or loosening the nuts. The volume of the slag collection hopper is 5 to 10 L.

[0013] The present invention relates to a method for air intake of a rake-type sootblower for cyclone slag removal in cement kilns under SCR denitrification, characterized in that: the automatic slag discharge valve is pneumatically controlled, adaptable to the working conditions of cement plant air source pressure of 0.4-0.6 MPa, realizing two modes: timed slag discharge or differential pressure triggered slag discharge. The slag discharge time can be adjusted by a PLC controller; the PLC controller presets a differential pressure value, and when the pressure difference value monitored by the pressure transmitter reaches the preset value, the PLC controller automatically controls the automatic slag discharge valve to open, and automatically closes after slag discharge is completed; at the same time, the PLC controller can feed back the operating status signal to the central control DCS system, which facilitates real-time monitoring of the device operation by the staff, adapting to the central control requirements of large-scale cement plant production.

[0014] The stainless steel filter screen can be replaced online. When the system prompts that the stainless steel filter screen needs to be replaced, the PLC controller automatically controls the inlet valve and outlet valve before and after the cyclone separator to close and the bypass valve to open. Compressed air enters the rake soot blower through the bypass, and can be replaced online at this time.

[0015] The spring-counterweight automatic flap slag discharge structure has symmetrically arranged spring-counterweight flaps that can flip downwards around the fulcrum. The middle spring keeps the flap closed under normal conditions. When the waste slag accumulates to the set weight, it overcomes the spring force to flip the flap downwards to discharge the slag. After the slag discharge is completed, the spring drives the flap to automatically reset and close. The spring preload can be changed by adjusting the nuts on both sides to achieve adjustable control of the slag discharge weight.

[0016] Beneficial Effects: Compared with existing technologies, this invention has the following significant advantages: Utilizing the principle of cyclone centrifugal separation, this invention can efficiently trap welding slag, rust, and fine cement dust in the air source, making it suitable for the high-temperature, high-dust, and alkaline corrosive conditions of cement plants. It achieves online automatic slag discharge without interrupting soot blowing operations. Simultaneously, this invention uses a simple nut-adjustable torque spring counterweight flap structure to effectively lock the air while discharging waste slag. Furthermore, this invention allows for online replacement of the stainless steel filter screen, effectively ensuring the continuous and stable operation of the rake soot blower and denitrification catalyst, reducing the operation and maintenance costs of cement plants. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the present invention;

[0018] Figure 2 This is a schematic diagram of the cyclone separator of the present invention;

[0019] Figure 3 for Figure 1 A schematic diagram of the local structure at point II;

[0020] Figure 4 for Figure 1 A schematic diagram of the local structure at point I;

[0021] Figure 5 for Figure 1 Schematic diagram of the structure at point I;

[0022] In the diagram, 1 is the air inlet pipe; 2 is guide plate one; 3 is guide plate two; 4 is guide vane; 5 is slag collection hopper; 6 is automatic slag discharge valve; 7 is cyclone separator; 8 is stainless steel filter screen one; 9 is the air outlet pipe; 10 is the outlet valve; 11 is pressure transmitter one; 12 is pressure transmitter two; 13 is the bypass air pipe; 14 is stainless steel filter screen two; 15 is the bypass valve; 16 is the inlet valve; 17 is the control unit; 18 is the rake soot blower; 19 is the spring counterweight flap; 20 is the spring; 21 is the nut; and 22 is the central shaft. Detailed Implementation

[0023] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0024] The present invention relates to a cyclone slag removal air intake system for a rake soot blower used in SCR denitrification of cement kilns, comprising an air intake pipe 1, one end of which is connected to a rake soot blower 18 for denitrification of cement kilns, and the other end which is tangentially connected to a cyclone separator 7 via a first guide plate 2 and a second guide plate 3, so that the air source rotates tangentially at high speed along the inner wall of the cyclone separator to form a centrifugal separation field; an air outlet pipe 9 is provided at the top of the cyclone separator 7, and the air outlet pipe 9 is sealed to the air inlet end of the rake soot blower 18 via a flange; a slag collection hopper 5 is provided at the bottom of the cyclone separator 7, and the slag collection hopper 5 is connected to the interior of the cyclone separator 7 for collecting solid impurities after separation; a spring counterweight flap 19 is provided at the bottom of the cyclone separator 7, and the counterweight of the flap is adjusted by adjusting the force of the spring 20 to achieve the dual functions of slag discharge and airlock; the cyclone separator 7 is further described in the following text. The upper part is equipped with a detachable stainless steel filter screen 8, and the middle part is equipped with guide vanes 4. The guide vanes 4 are set in accordance with the tangential air inlet to stabilize the airflow field and improve the separation efficiency. The air inlet pipe 1 and air outlet pipe 9 of the cyclone separator 7 are connected to pressure transmitter 11 and pressure transmitter 22 to monitor the pressure values ​​at the inlet and outlet of the cyclone separator 7, thereby calculating the pressure difference to determine whether the filter screen is blocked. The bottom of the slag collection hopper 5 is equipped with an automatic slag discharge valve 6 to control the discharge of impurities in the slag collection hopper. The automatic slag discharge valve 6, pressure transmitter 11, and pressure transmitter 22 are respectively connected to the PLC controller of the control unit 17 and linked with the central control DCS system of the control unit 17. According to the pressure difference value monitored by the transmitter, the automatic slag discharge valve is automatically controlled to start and stop, so as to realize automatic slag discharge.

[0025] The cyclone separator 7 of the present invention is provided with a stainless steel filter screen 8 at the top, an inlet valve 16 on the air inlet pipe 1, an outlet valve 10 on the air outlet pipe 9, a bypass valve 15 on the bypass pipe 13, and a stainless steel filter screen 14 on the bypass pipe 13 (to prevent impurities from entering the rake pipe when the stainless steel filter screen 8 is replaced online); the air inlet pipe 1 is provided with a guide plate 2 and a guide plate 3, which cooperate with the guide vanes 4 to prevent the separated solid impurities from flowing back into the air inlet pipe 1, and at the same time guide the compressed air to enter the cyclone separator 7 tangentially; the control unit 17 includes a PLC controller and an electrical switch.

[0026] The air inlet pipe 1, slag hopper 5, and cyclone separator 7 of this invention are made of stainless steel with a thickness of 2-4mm, which can withstand erosion and wear and extend the service life of the device. The inner wall of the cyclone separator 7 and slag hopper 5 is coated with a high-temperature resistant anti-corrosion coating or ceramic patch with a coating thickness of 0.3-0.5mm and the material is polytetrafluoroethylene or ceramic. The diameter of the cyclone separator 7 is 150-250mm, which is compatible with the current high-pressure soot blowing and low-pressure soot blowing modes. It can reasonably control the wind speed of the tangential air inlet, improve the centrifugal separation efficiency, and at the same time reduce the pressure loss of the cyclone separator without affecting the blowing pressure of the rake soot blower.

[0027] In this invention, the angle between the first guide plate 2, the second guide plate 3 and the air inlet pipe 1 is 10-15°; the angle between the guide blade 4 and the shell is 20-30°. The guide blade 4 has the same length or gradually increases in length along the direction of compressed air rotation to form an inner volute, so as to improve the cyclone slag removal efficiency.

[0028] The stainless steel filter screen 8 and stainless steel filter screen 14 of the present invention have a mesh size of 16 to 32, which prevents impurities larger than 1 mm from entering the rake tube and can effectively cover the current rake tube opening (about 2 mm to 3 mm in size). The filter screen edge is provided with a sealing groove, which is sealed to the inner wall of the cyclone separator. It can be quickly disassembled for cleaning or replacement by pressing with a flange.

[0029] The outlet valve 10, bypass valve 15, and inlet valve 16 of the present invention are pneumatically or electrically controlled, effectively realizing on / off control and transmitting feedback signals to the PLC control system.

[0030] The upper end of the slag collection hopper 5 of the present invention is connected to the conical part of the cyclone separator 7. The slag collection hopper 5 is equipped with a spring counterweight automatic flap slag discharge structure, which facilitates the settling of solid impurities. That is, the spring counterweight flap 19 and the spring 20 are installed on the central shaft 22 and fixed at both ends by nuts 21. The torque of the spring 20 is adjusted by tightening or loosening the nuts 21. The volume of the slag collection hopper 5 is 5 to 10L, which is suitable for the continuous ash blowing operation of cement plants and reduces the frequency of slag discharge.

[0031] The present invention relates to a method for air intake of a rake-type sootblower for cyclone slag removal in cement kilns under SCR denitrification, characterized in that: the automatic slag discharge valve 6 is pneumatically controlled, adaptable to the working conditions of cement plant air source pressure of 0.4-0.6 MPa, realizing two modes: timed slag discharge or differential pressure triggered slag discharge. The slag discharge time can be adjusted by a PLC controller; the PLC controller presets a differential pressure value, and when the pressure difference value monitored by the pressure transmitter reaches the preset value, the PLC controller automatically controls the automatic slag discharge valve 6 to open, and automatically closes after slag discharge is completed; at the same time, the PLC controller can feed back the operating status signal to the central control DCS system, which facilitates the real-time monitoring of the device operation by the staff, adapting to the central control needs of large-scale cement plant production.

[0032] The stainless steel filter screen 8 of the present invention can be replaced online. When the system prompts that the stainless steel filter screen needs to be replaced, the PLC controller automatically controls the inlet valve 16 and outlet valve 10 before and after the cyclone separator 7 to close, and the bypass valve 15 to open. Compressed air enters the rake soot blower 18 through the bypass 13, and can be replaced online at this time.

[0033] The spring-counterweight automatic flap slag discharge structure of the present invention has spring-counterweight flaps 19 symmetrically arranged and capable of flipping downward around the fulcrum. The middle spring 20 keeps the flap closed under normal conditions. When the upper waste slag accumulates to a set weight, it overcomes the spring force to flip the flap downward to discharge the slag. After the slag discharge is completed, the spring drives the flap to automatically reset and close. The spring preload can be changed by adjusting the nuts 21 on both sides, so as to realize the adjustable control of the slag discharge weight.

[0034] Example 1:

[0035] like Figure 1 As shown in this embodiment, the cyclone slag removal air intake system and method for a rake soot blower used in SCR denitrification of cement kilns is used for high-pressure soot blowing. The air source pressure is 0.4-0.6 MPa, the rake inlet air pipe is DN80, and the cyclone separator diameter is DN150. One end of the air inlet pipe 1 is connected to the main air source pipeline of the rake soot blower 18, and the other end is tangentially connected to the cyclone separator 7 through guide plate 1 2 and guide plate 2 3. The air outlet pipe 9 is located at the top of the cyclone separator 7 and is connected to the air inlet end of the rake soot blower 18 through a flange. The slag collection hopper 5 is fixed at the bottom of the cyclone separator 7, and the automatic slag discharge valve 6 is installed at the bottom of the slag collection hopper 5. The cyclone separator 7 is equipped with guide vanes 4, and the top of the cyclone separator 7 is equipped with stainless steel... A filter screen 8 is installed. An inlet valve 16 is installed on the inlet pipe 1, an outlet valve 10 is installed on the outlet pipe 9, a bypass valve 15 is installed on the bypass pipe 13, and a stainless steel filter screen 14 is installed on the bypass pipe 13. Pressure transmitters 11 and 12 are installed on the inlet pipe 1 and outlet pipe 9, respectively. The control unit 17 includes a PLC controller and electrical switches, etc. The PLC controller is linked with the automatic slag discharge valve 6, pressure transmitters 11 and 12, and the central control DCS system. A spring counterweight flap 19 is installed at the bottom of the cyclone separator 7. The spring 20 is installed on the central shaft 22 and fixed at both ends by nuts 21. The torque of the spring 20 can be adjusted by tightening or loosening the nuts 21. This invention can efficiently intercept welding slag, rust, and fine cement dust in the air source without interrupting the soot blowing operation. At the same time, this invention achieves effective airlocking while discharging waste slag through the simple nut-adjustable torque spring counterweight flap structure. In addition, this invention enables online replacement of stainless steel filter screens, effectively ensuring the continuous and stable operation of rake soot blowers and denitrification catalysts, and reducing the operation and maintenance costs of cement plants.

[0036] Example 2:

[0037] This embodiment is essentially the same as Example 1, except that it uses a rake-type sootblower for low-pressure soot blowing, with an air source pressure of 0.13–0.15 MPa, a DN125 inlet air pipe, and a DN200 diameter cyclone separator. It also achieves efficient slag removal, online automatic slag discharge, ensures soot blowing effect and stable operation of the denitrification system, is easy to maintain, and reduces operation and maintenance costs.

[0038] This invention utilizes the principle of cyclone centrifugal separation to efficiently trap welding slag, rust, and fine cement dust in the air source. It is suitable for the high-temperature, high-dust, and alkaline corrosive conditions of cement plants, enabling online automatic slag discharge without interrupting soot blowing operations. Simultaneously, the invention employs a spring-loaded counterweight flap structure with a simple nut for torque adjustment, effectively locking the airflow while discharging waste slag. Furthermore, this invention allows for online replacement of the stainless steel filter screen, effectively ensuring the continuous and stable operation of the rake soot blower and denitrification catalyst, reducing the operating and maintenance costs of cement plants.

Claims

1. A rake-type soot blower cyclone slag removal air intake system for SCR denitrification in cement kilns, characterized in that: The system includes an air inlet pipe (1), one end of which is connected to a rake-type soot blower (18) for denitrification in a cement kiln, and the other end is tangentially connected to a cyclone separator (7) via a guide plate (2) and a guide plate (3), so that the air source rotates tangentially along the inner wall of the cyclone separator at high speed to form a centrifugal separation field; the top of the cyclone separator (7) is provided with an air outlet pipe (9), which is sealed to the air inlet end of the rake-type soot blower (18); the bottom of the cyclone separator (7) is provided with a slag collection hopper (5), which is connected to the inside of the cyclone separator (7) to collect solid impurities after separation; the bottom of the cyclone separator (7) is provided with a spring counterweight flap (19), which adjusts the counterweight of the flap by adjusting the force of the spring (20) to achieve the dual functions of slag discharge and air lock; the upper part of the cyclone separator (7) is provided with a detachable stainless steel filter screen. The first (8) has a guide vane (4) in the middle, which is set with the tangential air inlet to stabilize the airflow field and improve the separation efficiency. The air inlet pipe (1) and air outlet pipe (9) of the cyclone separator (7) are connected to pressure transmitter one (11) and pressure transmitter two (12) to monitor the pressure values ​​at the inlet and outlet of the cyclone separator (7) and calculate the pressure difference to determine whether the filter screen is blocked. The bottom of the slag collection hopper (5) is equipped with an automatic slag discharge valve (6) to control the discharge of impurities in the slag collection hopper. The automatic slag discharge valve (6), pressure transmitter one (11) and pressure transmitter two (12) are respectively connected to the PLC controller of the control unit (17) and linked with the central control DCS system of the control unit (17). According to the pressure difference value monitored by the transmitter, the automatic slag discharge valve is automatically controlled to start and stop, so as to realize automatic slag discharge.

2. The rake-type soot blower cyclone slag removal air inlet system for SCR denitrification in cement kilns according to claim 1, characterized in that: The top of the cyclone separator (7) is provided with a stainless steel filter screen (8), the air inlet pipe (1) is provided with an inlet valve (16), the air outlet pipe (9) is provided with an outlet valve (10), the bypass pipe (13) is provided with a bypass valve (15), and the bypass pipe (13) is provided with a stainless steel filter screen (14). The air inlet pipe (1) is provided with a guide plate (2) and a guide plate (3). The guide plate and the guide blade (4) cooperate to prevent the solid impurities after separation from flowing back into the air inlet pipe (1) and guide the compressed air to enter the cyclone separator (7) tangentially. The control unit (17) includes a PLC controller and an electrical switch.

3. The rake-type soot blower cyclone slag removal air inlet system for SCR denitrification in cement kilns according to claim 2, characterized in that: The air inlet pipe (1), slag collection hopper (5), and cyclone separator (7) are made of stainless steel with a thickness of 2-4 mm. The inner walls of the cyclone separator (7) and slag collection hopper (5) are coated with a high-temperature resistant anti-corrosion coating or ceramic patch with a coating thickness of 0.3-0.5 mm and made of polytetrafluoroethylene or ceramic. The diameter of the cyclone separator (7) is 150-250 mm.

4. The rake-type soot blower cyclone slag removal air inlet system for SCR denitrification in cement kilns according to claim 1, characterized in that: The angle between the first guide plate (2), the second guide plate (3) and the air inlet pipe (1) is 10-15°; the angle between the guide blade (4) and the shell is 20-30°. The guide blade (4) has the same length or gradually increases in length along the direction of compressed air rotation to form an inner volute, so as to improve the cyclone slag removal efficiency.

5. The rake-type soot blower cyclone slag removal air inlet system for SCR denitrification in cement kilns according to claim 2, characterized in that: The stainless steel filter screen one (8) and stainless steel filter screen two (14) have a mesh size of 16 to 32 to prevent impurities larger than 1 mm from entering the rake tube. The filter screen edge is provided with a sealing groove to seal and connect with the inner wall of the cyclone separator.

6. The rake-type soot blower cyclone slag removal air inlet system for SCR denitrification in cement kilns according to claim 2, characterized in that: The outlet valve (10), bypass valve (15), and inlet valve (16) are pneumatically or electrically controlled to effectively realize switch control and transmit feedback signals to the PLC control system.

7. The rake-type soot blower cyclone slag removal air intake system for SCR denitrification in cement kilns according to claim 1, characterized in that: The upper end of the slag collection hopper (5) is connected to the cone of the cyclone separator (7). The slag collection hopper (5) is equipped with a spring counterweight automatic flap slag discharge structure, which facilitates the settling of solid impurities. That is, the spring counterweight flap (19) and spring (20) are installed on the central shaft (22) and fixed at both ends by nuts (21). The torque of the spring (20) is adjusted by tightening or loosening the nuts (21). The volume of the slag collection hopper (5) is 5 to 10 L.

8. A method for using the rake-type soot blower cyclone slag removal air intake system for SCR denitrification in cement kilns according to any one of claims 1-7, characterized in that: The automatic slag discharge valve (6) is pneumatically controlled and is suitable for cement plant air source pressure of 0.4 to 0.6 MPa. It realizes two modes: timed slag discharge or differential pressure triggered slag discharge. The slag discharge time can be adjusted by the PLC controller. The PLC controller presets the differential pressure value. When the pressure difference value detected by the pressure transmitter reaches the preset value, the PLC controller automatically controls the automatic slag discharge valve (6) to open and automatically closes after slag discharge is completed. At the same time, the PLC controller can feed back the operating status signal to the central control DCS system, which is convenient for staff to monitor the operation of the device in real time and adapts to the central control needs of large-scale production in cement plants.

9. The method for air intake of a rake-type soot blower for SCR denitrification in cement kilns according to claim 8, characterized in that: The stainless steel filter screen (8) can be replaced online. When the system prompts that the stainless steel filter screen needs to be replaced, the PLC controller automatically controls the inlet valve (16) and outlet valve (10) before and after the cyclone separator (7) to close, and the bypass valve (15) to open. Compressed air enters the rake blower (18) through the bypass (13), and can be replaced online at this time.

10. The method for air intake of a rake-type soot blower for SCR denitrification in cement kilns according to claim 8, characterized in that: The spring counterweight automatic flap slag discharge structure has spring counterweight flaps (19) arranged symmetrically and can be flipped downward around the fulcrum. The middle spring (20) keeps the flap closed under normal conditions. When the upper waste slag accumulates to the set weight, it overcomes the spring force to make the flap flip down to discharge the slag. After the slag is discharged, the spring drives the flap to automatically reset and close. The spring preload can be changed by adjusting the nuts (21) on both sides to achieve adjustable control of the slag discharge weight.

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