Bypass ventilation dechlorination method and bypass ventilation dechlorination equipment used by bypass ventilation dechlorination method

Abstract

The invention discloses a bypass exhaust dechlorination method and bypass exhaust dechlorination equipment used by the bypass exhaust dechlorination method. The bypass exhaust dechlorination method comprises the following steps: step 1, feeding kiln tail flue gas into shock cooling equipment (1) for cooling; 2, the cooled flue gas enters high-temperature dust removal equipment to be subjected to gas-solid separation; and 3, the waste gas obtained through separation in the step 2 is fed into a preheater (101), and the temperature of the waste gas fed into the preheater (101) in the step 3 is higher than 400 DEG C. According to the bypass ventilation dechlorination method, the smoke of the kiln tail smoke chamber is extracted through the pressure difference between the kiln tail smoke chamber and the preheater, after high-temperature dust removal treatment, waste gas returns to the preheater and is subjected to denitrification treatment together with system waste gas, and additional equipment does not need to be additionally arranged.

Description

Technical Field

[0001] The present invention relates to the field of bypass air extraction for chlorine removal, and specifically, to a method for bypass air extraction for chlorine removal and a bypass air extraction chlorine removal device used therefor. Background Art

[0002] With the gradual advancement of energy conservation and carbon reduction, more and more cement clinker production lines use alternative fuels and co-dispose various solid and hazardous wastes. Through theoretical calculation, the interfering elements (K, Na, S, Cl) brought into the cement kiln system by alternative fuels or solid and hazardous wastes account for about 50-60% of the total interfering elements. These elements will undergo cyclic enrichment in the cement clinker firing system. Seriously, it will affect the quality of cement clinker products, and even interfere with the entire thermal regime and affect the normal operation of the cement kiln system.

[0003] According to the volatilization and condensation characteristics of various compounds (potassium chloride, sodium chloride, etc.) produced by interfering elements, therefore, the bypass air extraction method is usually adopted to remove the interfering elements in the cement clinker firing system.

[0004] The traditional bypass air extraction system at the kiln tail of a cement kiln adopts external treatment after multi-stage cooling of high-temperature gas. Specifically: a certain amount of high-temperature air is extracted from the kiln tail smoke chamber through an air extraction device, and the extracted high-temperature gas is cooled by an air cooler. The high-temperature gas is cooled to about 400°C. At this time, the gas temperature is far lower than the melting point temperature of harmful substances such as potassium chloride, and harmful substances such as potassium chloride begin to condense. These condensed solid dusts enter the cyclone with the flue gas for gas-solid separation to separate the coarse dust in the flue gas. The separated flue gas will enter the heat exchanger or waste heat power generation boiler for secondary cooling. At this time, the flue gas temperature drops to 180°C, and the fine dust in it is removed by a bag filter, and the filtered gas enters the waste gas treatment system.

[0005] The traditional bypass air extraction system at the kiln tail of a cement kiln needs to set up a fan to extract the flue gas from the kiln tail smoke chamber, and the high-temperature gas needs multi-stage cooling. Therefore, the entire system has high energy consumption, and the waste gas discharged from the system contains nitrogen oxides and additional purification equipment needs to be configured separately, and the cost of additional equipment is also very high. Summary of the Invention

[0006] The purpose of the present invention is to provide a method for bypass air extraction for chlorine removal and a bypass air extraction chlorine removal device used therefor. This method for bypass air extraction for chlorine removal is conducive to extracting the flue gas from the kiln tail smoke chamber by using the pressure difference between the kiln tail smoke chamber and the preheater. After high-temperature dust removal treatment, the waste gas returns to the preheater and is denitrified together with the system waste gas, and no additional equipment needs to be configured separately.

[0007] To achieve the above purpose, the present invention provides a method for bypass air extraction for chlorine removal, including:

[0008] Step 1, extracting the kiln tail flue gas and sending it to a quenching device for cooling;

[0009] Step 2: The cooled flue gas enters a high-temperature dust removal device for gas-solid separation;

[0010] Step 3: The waste gas separated in Step 2 is sent to a preheater.

[0011] Among them, the temperature of the waste gas sent to the preheater in Step 3 is higher than 400 °C.

[0012] Preferably, the outlet temperature of the quenching device in Step 1 is 600 - 700 °C.

[0013] The present invention also provides a bypass air extraction chlorine removal device for using the bypass air extraction chlorine removal method, including a quenching device and a high-temperature dust removal device connected in sequence. One end of the quenching device is communicated with the kiln tail smoke chamber, the other end is communicated with the inlet of the high-temperature dust removal device, and the outlet of the high-temperature dust removal device is communicated with the preheater.

[0014] Preferably, the high-temperature dust removal device includes a primary cyclone and a high-temperature moving particle bed filtration device connected in sequence.

[0015] Preferably, the ash outlet of the primary cyclone is communicated with the kiln tail smoke chamber.

[0016] Preferably, the high-temperature moving particle bed filtration device includes a filter body, a separator connected to the filter body and located below the filter body, a filter material conveyor with an inlet communicated with the separator, the outlet of the filter material conveyor is connected to the top of the filter body, and an air outlet and an air inlet are respectively arranged above and below the filter body.

[0017] Preferably, the separator is provided with a first discharge port and a second discharge port. The first discharge port is connected to the filter material conveyor, and the high-temperature moving particle bed filtration device further includes a storage tank, and the second discharge port is communicated with the storage tank.

[0018] Preferably, the quenching device is provided with a temperature sensor. The temperature sensor detects the outlet air temperature of the quenching device, and the temperature sensor is electrically connected to the quenching fan of the quenching device to control the rotation speed of the quenching fan.

[0019] According to the above technical solution, the environment inside the cement kiln system is a negative pressure environment. The air pressure at the preheater position is approximately -4500 to -5500 Pa, and the air pressure inside the kiln tail smoke chamber is approximately -50 to -100 Pa. Therefore, there is a pressure difference between the kiln tail smoke chamber and the preheater. Under the action of this pressure difference, the flue gas in the kiln tail smoke chamber will move towards the preheater.

[0020] By utilizing the pressure difference between the preheater and the kiln tail flue gas chamber, the flue gas in the kiln tail flue gas chamber can be smoothly extracted through the air intake opening. After these flue gases are rapidly cooled to a temperature not higher than 700 °C by a quenching device, the harmful substances in the flue gases can be condensed. Generally, the freezing point of chlorides is 770 °C. Through the cooling effect of the quenching device, gaseous chlorine can be rapidly converted into solid salts attached to dust. Dust particles with solid salts attached to their outer surfaces can achieve gas-solid separation after entering a high-temperature dust removal device, and the separated waste gas with solid dust particles is recycled into the preheater.

[0021] The exhaust temperature of the preheater is generally 320 °C. If the temperature of the introduced waste gas is lower than 320 °C, then these introduced waste gases cannot provide energy for the preheater, and even need to absorb the energy of the preheater, resulting in an increase in energy consumption inside the preheater. Therefore, the temperature of the waste gas treated by the bypass air extraction method for chlorine removal should be higher than 400 °C. When using this bypass air extraction method for chlorine removal, since the process flow is simple, the heat loss of the flue gas during the treatment process is very small. Therefore, the temperature of the waste gas can almost be maintained at the temperature at the outlet of the quenching device. Preferably, when the outlet temperature of the quenching device is set to 700 °C, the temperature of the waste gas entering the preheater can also almost reach 700 °C.

[0022] By performing gas-solid separation on the flue gas output from the quenching device, the harmful solid salts in the flue gas can be effectively removed, realizing the chlorine removal treatment of the cement kiln system. By utilizing the pressure difference between the kiln tail flue gas chamber and the preheater, the extraction of the flue gas can be achieved. Therefore, when using this bypass air extraction method for chlorine removal, the original air extraction fan is cancelled, saving the energy consumption of the system. The waste gas treated by this bypass air extraction method for chlorine removal will ultimately be sent back to the preheater and, together with the gas in the preheater, will undergo denitrification treatment through the denitrification device of the system.

[0023] In summary, using the bypass air extraction method for chlorine removal of the present invention can achieve chlorine removal from the kiln tail flue gas chamber without using an air extraction fan. The chlorine-removed waste gas is introduced into the preheater, and denitrification can also be carried out using the denitrification device of the system without the need to additionally configure a denitrification device, which can save a large amount of fixed asset investment.

[0024] Other features and advantages of the present invention will be described in detail in the subsequent specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following specific implementation, they are used to explain the present invention, but do not constitute a limitation to the present invention. In the drawings:

[0026] Figure 1 is a schematic diagram of a bypass air extraction device for chlorine removal;

[0027] Figure 2 It is a schematic diagram of a wind locking valve.

[0028] Description of the reference numerals in the drawings

[0029] 1 Quenching equipment 101 Preheater

[0030] 102 Kiln tail smoke chamber 2 Primary cyclone

[0031] 31 Filter body 32 Separator

[0032] 33 Filter material conveyor 34 Air outlet

[0033] 35 Air inlet 36 Storage tank

[0034] 11 Quenching fan 4 Wind locking valve

[0035] 41 Accommodating cavity 42 Housing Specific implementation manners

[0036] The following describes in detail the specific implementation manners of the present invention with reference to the accompanying drawings. It should be understood that the specific implementation manners described herein are only used to illustrate and explain the present invention and are not used to limit the present invention.

[0037] In the present invention, unless otherwise stated, the directional terms included in terms such as "one end, the other end, outer surface, axis, conical, close to" only represent the direction of the term in the normal use state, or the common name understood by those skilled in the art, and should not be regarded as a limitation to the term.

[0038] On the one hand, the present invention provides a method for bypass air extraction and chlorine removal, including:

[0039] Step 1: Take the kiln tail flue gas and send it to the quenching equipment 1 for cooling;

[0040] Step 2: The cooled flue gas enters the high-temperature dust removal equipment for gas-solid separation;

[0041] Step 3: The waste gas separated in Step 2 is sent to the preheater 101.

[0042] Among them, the temperature of the waste gas sent to the preheater 101 in Step 3 is higher than 320 °C.

[0043] The cement kiln system is in a negative pressure environment. The air pressure at the position of the preheater 101 is about -4500 to -5500 Pa, and the air pressure in the kiln tail smoke chamber 102 is about -200 to -300 Pa. Therefore, there is a pressure difference between the kiln tail smoke chamber 102 and the preheater 101. Under the action of this pressure difference, the flue gas in the kiln tail smoke chamber 102 will move towards the preheater 101.

[0044] By using the pressure difference between the preheater 101 and the kiln tail flue gas chamber 102, the flue gas in the kiln tail flue gas chamber 102 can be smoothly taken out through the air intake opening. These flue gases are quickly cooled to a temperature not higher than 700 °C by the quenching device 1, which can condense the harmful substances in the flue gas. The freezing point of chloride salts is generally 770 °C. Through the cooling effect of the quenching device 1, gaseous chlorine can be quickly converted into solid salt attached to the dust. The dust particles with solid salt attached to the outer surface can achieve gas-solid separation after entering the high-temperature dust removal device, and the waste gas after the solid dust particles are separated is recycled into the preheater 101.

[0045] The exhaust temperature of the preheater 101 is generally 320 °C. If the temperature of the introduced waste gas is lower than 320 °C, then these introduced waste gases cannot provide energy for the preheater 101, and even need to absorb the energy of the preheater 101, which will increase the energy consumption in the preheater 101. Therefore, the temperature of the waste gas treated by the bypass air extraction method for chlorine removal should be higher than 320 °C. When using this bypass air extraction method for chlorine removal, due to the simple process flow, the heat loss of the flue gas during the treatment process is very small. Therefore, the temperature of the waste gas can almost be maintained at the temperature at the outlet of the quenching device. Preferably, when the outlet temperature of the quenching device is set to 700 °C, the temperature of the waste gas entering the preheater can also almost reach 700 °C.

[0046] By performing gas-solid separation on the flue gas output by the quenching device 1, the harmful solid salt in the flue gas can be effectively removed, realizing the chlorine removal treatment of the cement kiln system. By using the pressure difference between the kiln tail flue gas chamber 102 and the preheater 101, the extraction of the flue gas can be achieved. Therefore, when using this bypass air extraction method for chlorine removal, the original air extraction fan is cancelled, saving the energy consumption of the system. The waste gas treated by this bypass air extraction method for chlorine removal will ultimately be sent back to the preheater 101 and, together with the gas in the preheater 101, will undergo denitrification treatment through the denitrification device of the system.

[0047] In summary, using the bypass air extraction method for chlorine removal of the present invention can achieve chlorine removal of the kiln tail flue gas chamber 102 without using an air extraction fan. The waste gas after chlorine removal is introduced into the preheater 101, and the denitrification device of the system can also be used for denitrification, without the need to additionally configure a denitrification device, which can save a large amount of fixed asset investment.

[0048] In this embodiment, preferably, the outlet temperature of the quenching device 1 in step 1 is 600 - 700 °C.

[0049] Setting the outlet temperature of the quench device 1 at 600 - 700 °C can achieve the heat recovery of high-temperature flue gas. When the temperature of the high-temperature flue gas is lower than 770 °C, the chloride salt begins to cool. When the flue gas temperature in the quench device 1 drops suddenly to 700 °C, the chloride salt in the flue gas cools rapidly and adheres to the surface of the solid dust in the flue gas. During the subsequent treatment process, each device has heat preservation measures, and with this bypass air extraction chlorine removal method, the process is simple. Therefore, the heat loss in the system is very small, and the temperature of the waste gas can finally be maintained at 600 - 700 °C when it enters the preheater 101. Then, after these high-temperature waste gases enter the preheater 101, they can provide energy to the preheater 101, thus realizing the heat recovery of the high-temperature flue gas.

[0050] On the other hand, the present invention provides a bypass air extraction chlorine removal device for use in a bypass air extraction chlorine removal method, comprising a quench device 1 and a high-temperature dust removal device connected in sequence. One end of the quench device 1 is communicated with the kiln tail smoke chamber 102, and the other end is communicated with the inlet of the high-temperature dust removal device. The outlet of the high-temperature dust removal device is communicated with the preheater 101.

[0051] The quenched flue gas enters the high-temperature dust removal device for gas-solid separation. The waste gas obtained after the solid dust is separated enters the preheater 101. Through the preheater 101, the purpose of recovering the waste gas in the bypass air extraction chlorine removal device can be achieved. Then, these recovered gases enter the cement kiln system and enter the gas purification device of the system together with the gases in the cement kiln system, thus realizing the zero-emission purpose of the bypass air extraction chlorine removal device.

[0052] The temperature in the kiln tail smoke chamber 102 of the cement kiln is about 1050 °C. The high-temperature dust-containing gas at the air intake position is extracted by the bypass air extraction chlorine removal device under the action of the pressure difference. After the high-temperature flue gas is extracted, it enters the quench device 1 for quenching, so that the flue gas temperature drops to 600 - 700 °C. The harmful substances in the flue gas condense and adhere to the surface of the solid dust in the flue gas. These flue gases are subjected to gas-solid separation by the high-temperature dust removal device, and the separated waste gas is sent to the preheater 101. The entire

[0053] bypass air extraction chlorine removal device is heat-insulated to minimize the heat loss of the flue gas after it enters the bypass air extraction chlorine removal device. Due to the simple structure of this bypass air extraction chlorine removal device, the heat loss during the treatment of high-temperature flue gas is small. Usually, the temperature of the waste gas entering the preheater 101 can be maintained at 600 - 700 °C.

[0054] In this embodiment, preferably, the high-temperature dust removal device comprises a primary cyclone 2 and a high-temperature moving particle bed filtration device connected in sequence.

[0055] The flue gas contains solid dust, which can be roughly divided into coarse particulate dust and fine particulate dust according to the particle size. In the quenched flue gas, solid salts will adhere to the surface of these solid dusts. Since the specific surface area of fine particulate dust is much larger than that of coarse particulate dust, more solid salts are carried by the fine particulate dust in the flue gas.

[0056] The coarse particulate dust with less solid salt in the flue gas can be recovered through the primary cyclone 2.

[0057] The diameter of the primary cyclone 2 is set to be relatively large. A cyclone with a larger diameter can collect coarse particulate dust with large particle sizes, and a cyclone with a larger diameter also has higher processing efficiency. Therefore, placing the primary cyclone 2 after the quenching device 1 can collect the coarse particulate dust in the flue gas first without affecting the processing efficiency. After being processed by the primary cyclone 2, the workload of the high-temperature moving particle bed will be relatively reduced, which is beneficial to improving the working efficiency of the high-temperature moving particle bed and reducing the system resistance.

[0058] In this embodiment, preferably, the ash discharge port of the primary cyclone 2 is communicated with the kiln tail smoke chamber 102.

[0059] Due to the small specific surface area of the solid in the coarse particulate dust and the small amount of solid salt carried, the captured coarse particulate dust can be sent back to the kiln tail smoke chamber 102, thereby reducing the dust emission of the bypass air extraction chlorine removal equipment and reducing the subsequent treatment amount of solid ash.

[0060] In this embodiment, preferably, the high-temperature moving particle bed filtration device includes a filter body 31, a separator 32 connected to the filter body 31 and located below the filter body 31, and a filter material conveyor 33 with an inlet communicated with the separator 32. The outlet of the filter material conveyor 33 is connected to the top of the filter body 31. An air outlet 34 and an air inlet 35 are respectively arranged above and below the filter body 31.

[0061] The high-temperature moving particle bed is filled with heat-resistant filter materials. Therefore, the working temperature of the high-temperature moving particle bed is very high, and it can filter high-temperature flue gas.

[0062] The flue gas enters the filter body 31 from the air inlet 35. Subsequently, under the action of the system pressure, the flue gas gradually moves towards the direction of the air inlet 35. The filter body 31 is filled with filter materials. During the upward movement of the flue gas, it comes into contact with the filter materials. The solid particulate dust with larger particle sizes in the flue gas will be intercepted by the pores of the filter materials. At the same time, during the high-speed movement, the small particulate dust in the air flow will be captured due to inertial impact on the filter materials. Therefore, during the upward movement of the flue gas, the filter materials will intercept the solid particulate dust in the flue gas, and the waste gas will rise to the air outlet 34 and flow out of the air outlet 34 to the preheater 101.

[0063] Preferably, a control discharge valve is provided at the bottom of the high-temperature moving particle bed. The control discharge valve rotates continuously and drives the filter material in the filter body 31 to flow out to the separator 32. The separator 32 separates the filter material from the solid particle dust. The separated filter material will be returned above the filter body 31 via the filter material conveyor 33, thus realizing the regeneration and circulation of the filter material.

[0064] During the circulation of the filter material, new filter material always enters the upper part of the filter body 31. Therefore, by this way of circulating and moving the filter material, the gas-solid separation effect of the filter body 31 on the flue gas can be improved.

[0065] During the circulating movement of the filter material, the filter material also slowly moves downward in the filter body 31, enters the separator 32 through the control discharge valve, and is filtered in the separator 32. The separator can remove the solid particle dust in the filter material. The process of filter material circulation can not only ensure the continuous update of the filter surface, but also effectively avoid blockage; after the filter material filtered by the separator 32 enters the filter body 31 again, it can reliably intercept the solid particle dust in the flue gas and maintain the filtration efficiency.

[0066] Preferably, a air lock valve 4 is provided on the pipeline connecting the filter body 31 and the separator 32 for sealing the gas path system.

[0067] The air lock valve 4 is set as a rotary type. A plurality of accommodating cavities 41 are circumferentially distributed on the valve core. The valve core is hermetically connected to the housing 42 of the valve, and each time the valve core rotates by one accommodating cavity 41.

[0068] After the filter material moves to the position of the air lock valve 4, it will fall into the accommodating cavity 41 for storage. When the valve core rotates, an accommodating cavity 41 filled with filter material on the side facing the filter body 31 will cross the sealing position between the valve core and the housing 42 and enter the side facing the separator 32. During the rotation of the valve core, the filter material in the accommodating cavity 41 will fall into the lower separator 32, and an empty accommodating cavity 41 on the other side corresponding to this accommodating cavity 41 will also cross the sealing position between the valve core and the housing 42 and enter the side connected to the filter body 31. Therefore, by setting the air lock valve 4, while transporting the filter material to the separator 32, the airtight effect of the system can be effectively achieved.

[0069] Preferably, an air lock valve 4 is also provided in the pipeline where the filter material conveyor 33 returns to the filter body 31 for realizing the airtight of the system while transporting the filter material.

[0070] By adjusting the rotation speed of the control discharge valve, the filtering effect of the filter body 31 can be regulated. When it is necessary to increase the filtering effect of the filter body 31, the rotation speed of the control discharge valve can be reduced, so that the gap between the filtering materials in the filter body 31 is smaller, in order to effectively intercept the solid particles in the flue gas; conversely, when it is necessary to increase the exhaust speed of the waste gas, the rotation speed of the control discharge valve needs to be increased, so that the gap between the filtering materials in the filter body 31 is larger, making the resistance of the flue gas passing through the filter body 31 smaller, reducing the residence time of the flue gas in the bypass air extraction chlorine removal equipment, reducing the resistance of the system, and reducing the heat loss of the flue gas in the system.

[0071] Since there is no power such as a fan in the bypass air extraction chlorine removal equipment, and the air extraction of the kiln tail smoke chamber 102 is realized only by the pressure difference at both ends, therefore, preferably, the rotation speed of the discharge valve is flexibly adjusted by frequency conversion control to ensure the stability of the material bed resistance, so that the bypass air extraction chlorine removal equipment can continuously and stably realize the air extraction function of the kiln tail smoke chamber 102.

[0072] When the rotation speed of the discharge valve is set to be low, its resistance will increase and affect the ventilation volume, which can be compensated by increasing the rotation speed of the discharge valve. By accelerating the discharge speed, reducing the material bed resistance, and increasing the air extraction volume, the bypass air extraction chlorine removal equipment can extract more harmful substances per unit time, and then the sufficient separation of harmful substances in the system can be realized.

[0073] In one implementation, multiple parallel-connected bypass air extraction chlorine removal equipment are provided. The multiple parallel-connected bypass air extraction chlorine removal equipment can effectively increase the processing capacity of the flue gas. In another implementation, the size of the air extraction port at the connection between the bypass air extraction chlorine removal equipment and the kiln tail smoke chamber 102 can be increased, and the purpose of increasing the air extraction volume can also be achieved by increasing the size of the air extraction port.

[0074] In this implementation, preferably, the separator 32 is provided with a first discharge port and a second discharge port. The first discharge port is connected to the filter material conveyor 33, and the high-temperature moving particle bed filtration device further includes a storage tank 36. The second discharge port is communicated with the storage tank 36.

[0075] In one implementation, the separator 32 is set to be capable of vibrating. Through the vibration of the separator 32, the filtering material is separated from the solid dust attached to its surface. Since the particle size of the filtering material is much larger than that of the particulate dust, therefore, the separated filtering material and particulate dust can be reliably separated by vibration screening, thereby realizing the regeneration function of the filtering material.

[0076] In another implementation, a reverse purge can also be provided on the surface of the separator 32, and the reliable separation of the filtering material and the solid particulate dust is realized through the reverse purge action of the air flow.

[0077] The separated filter material and particulate dust are respectively output through the first discharge port and the second discharge port. The filter material enters the filter material conveyor 33 and is finally transported to the filter body 31, while the particulate dust is collected in the storage tank 36. When the collected amount reaches the set value, these particulate dusts will be transferred out for harmless treatment.

[0078] In this embodiment, preferably, the quenching device 1 is provided with a temperature sensor. The temperature sensor detects the outlet air temperature of the quenching device 1, and the temperature sensor is electrically connected to the quenching fan 11. The temperature sensor controls the rotation speed of the quenching fan 11 of the quenching device 1.

[0079] In order to maximize the heat recovery of the high-temperature flue gas, therefore, a temperature sensor needs to be provided at the air outlet 34 of the quenching device 1 to detect the outlet air temperature of the quenching device 1. If the outlet air temperature is lower than 600 °C, this temperature sensor can control to reduce the rotation speed of the quenching fan 11, so that less cold air enters the quenching device 1, thereby reducing the cooling effect of the quenching device 1 and increasing the temperature of the flue gas. If the temperature sensor detects that the temperature at the air outlet 34 of the quenching device 1 is greater than 700 °C, then it is necessary to increase the rotation speed of the quenching fan 11 to increase the cooling effect of the quenching device 1 and reduce the outlet temperature of the quenching device 1, so that the solid salt can be reliably cooled and condensed.

[0080] Preferably, a temperature sensor can also be provided at the connection between the preheater 101 and the bypass air release and chlorine removal device. By detecting the temperature of the waste gas entering the preheater 101, the rotation speed of the quenching fan 11 is controlled. When the temperature of the waste gas entering the preheater 101 is relatively low, it is necessary to reduce the rotation speed of the quenching fan 11 so that the temperature of the high-temperature flue gas after being cooled will not be too low. Usually, the temperature at the air outlet 34 of the quenching device 1 needs to be set at 700 °C. After being treated by the bypass air release and chlorine removal device, the temperature of the waste gas can still be maintained at about 700 °C.

[0081] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0082] In addition, it should be noted that, in the above specific embodiments, the various specific technical features described can be combined in any suitable manner without conflict. To avoid unnecessary repetition, the present invention will not separately describe various possible combination methods.

[0083] In addition, any combination can be made between various different embodiments of the present invention as long as it does not violate the idea of the present invention, and it should also be regarded as the content disclosed by the present invention.

Claims

1. A method for removing chlorine by bypass air release, characterized in that, Comprising: Step 1: Take the flue gas from the kiln tail and send it to the quenching device (1) for cooling; Step 2: The cooled flue gas enters the high-temperature dust removal device for gas-solid separation; Step 3: The waste gas separated in Step 2 is sent to the preheater (101); Wherein, the temperature of the waste gas sent to the preheater (101) in Step 3 is higher than 400 °C.

2. The bypass air release chlorine removal method according to claim 1, wherein The outlet temperature of the quenching device (1) in Step 1 is 600 - 700 °C.

3. The bypass air release chlorine removal equipment used in the bypass air release chlorine removal method according to claim 1 or 2, characterized in that, It includes a quenching device (1) and a high-temperature dust removal device connected in sequence. One end of the quenching device (1) is communicated with the kiln tail smoke chamber (102), and the other end is communicated with the inlet of the high-temperature dust removal device. The outlet of the high-temperature dust removal device is communicated with the preheater (101).

4. The bypass air release chlorine removal device according to claim 3, characterized in that, The high-temperature dust removal device includes a primary cyclone (2) and a high-temperature moving particle bed filtration device connected in sequence.

5. The bypass air release chlorine removal device according to claim 4, wherein The ash outlet of the primary cyclone (2) is communicated with the kiln tail smoke chamber (102).

6. The bypass air release chlorine removal device according to claim 4, characterized in that, The high-temperature moving particle bed filtration device includes a filter body (31), a separator (32) located below the filter body (31) and connected to the filter body (31), a filter material conveyor (33) with an inlet communicated with the separator (32). The outlet of the filter material conveyor (33) is connected to the top of the filter body (31). An air outlet (34) and an air inlet (35) are respectively arranged above and below the filter body (31).

7. The bypass air release chlorine removal device according to claim 6, characterized in that, The separator (32) is provided with a first discharge port and a second discharge port. The first discharge port is connected to the filter material conveyor (33). The high-temperature moving particle bed filtration device further includes a storage tank (36), and the second discharge port is communicated with the storage tank (36).

8. The bypass air release chlorine removal device according to claim 3, characterized in that The quenching device (1) is provided with a temperature sensor. The temperature sensor detects the outlet air temperature of the quenching device (1). The temperature sensor is electrically connected to the quenching fan (11) of the quenching device (1), and the temperature sensor controls the rotation speed of the quenching fan (11).

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