Roller kiln flue gas treatment equipment and flue gas treatment method

Abstract

The invention discloses roller kiln flue gas treatment equipment and a flue gas treatment method, and belongs to the technical field of in-kiln flue gas treatment.The roller kiln flue gas treatment equipment comprises a gas inlet pipeline, a first combustion chamber and an exhaust pipeline, the gas inlet pipeline is communicated with one end of the first combustion chamber, and the exhaust pipeline is communicated with the other end of the first combustion chamber; the first combustion chamber is internally provided with at least one flue gas catalytic device, the flue gas catalytic device is arranged in the first combustion chamber, the flue gas catalytic device comprises a grid and a catalyst carrier, the grid is arranged in the flue gas catalytic device, the catalyst carrier is arranged in the grid, and the catalyst carrier is arranged in the grid. The catalyst carrier is in contact with the flue gas to convert the flue gas into harmless gas, and the catalyst carrier can be replaced after loss or inactivation, so that the flue gas conversion efficiency is ensured, open fire conversion is avoided, and the use safety of equipment is improved.

Description

Technical Field

[0001] The invention relates to the technical field of fume treatment in a kiln, and in particular to a fume treatment device and a fume treatment method for a roller kiln. Background Art

[0002] With the development of new energy technologies, high-energy-density lithium batteries have been widely used. The existing manufacturing process of lithium battery electrode materials is that the raw materials are sintered at high temperatures in a kiln. During the sintering process of the electrode materials, a chemical reaction occurs, and harmful gases will evaporate from the temperature-rising zone in the kiln and mix into the flue gas. The temperature of this part of the flue gas is relatively high, and most of the harmful substances can be converted and removed through combustion oxidation reactions. Most of the existing sintering processes are in the temperature-raising section of the kiln, that is, an incinerator is added before the smoke exhaust fan. The incinerator is equipped with a gas burner, and the harmful gas is heated again by open flame combustion of the gas and combustion-supporting air, so that the harmful substances are converted into harmless gas and then discharged. The above-mentioned open flame combustion has its limitations. The addition of fuel gas to heat the flue gas increases energy consumption; the combustion-supporting gas requires a separate pipeline and combustion-supporting fan, which increases the construction cost; the total volume flow in the pipeline increases sharply with the addition of combustion gas, combustion-supporting gas and heated harmful gas, and the thickness of the high-temperature refractory insulation layer needs to be increased, resulting in a large volume of the incinerator, which further increases the construction cost; the combustion of the gas itself will also produce harmful substances, especially the N element, which may be converted into NOx at high temperature; the combustion condition control requirements are high, and the flue gas temperature at the end is too high, which will damage the fan and pipeline; in addition, the open flame combustion method has the potential risk of deflagration, which will pose a threat to personal safety, so a non-open flame flue gas treatment equipment is needed to convert and treat the flue gas in the kiln.

[0003] The existing patent application with publication number CN111396943A discloses a barbecue smoke purification device for a smokeless purification barbecue vehicle, including a processing chamber, a sealing connection component and a smoke exhaust pipe. The processing chamber is detachably fixed on the outer circumference of a smoke exhaust pipe with a diameter within a certain range by using the sealing connection component, and the sealing connection component can be sealed and connected to the smoke exhaust pipe, so that all the oil smoke from the smoke exhaust pipe can enter the processing chamber; the processing chamber is provided with a combustion smoke removal component and a catalytic smoke removal component, and the combustion smoke removal component includes an oil dropper and a combustion tube, the oil dropper can capture some molecular particles in the oil smoke to form droplets, and the combustion tube can evenly spray high-temperature flames upward. The smoke purification device uses open flame combustion to treat harmful substances produced by combustion, which will pose a threat to personal safety. Summary of the invention

[0004] One of the purposes of the present invention is to provide a roller kiln fume treatment device, which solves the problem that the existing sintering electrode material fume treatment equipment uses open flame combustion to remove harmful substances, has high construction costs and large energy consumption.

[0005] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention is as follows:

[0006] A roller kiln flue gas treatment device comprises an air intake duct, a first combustion chamber and an exhaust duct, wherein the air intake duct is connected to one end of the first combustion chamber, and the exhaust duct is connected to the other end of the first combustion chamber. At least one flue gas catalytic device is arranged in the first combustion chamber, and the flue gas catalytic device comprises a grille and a catalyst carrier, wherein the grille is arranged in the flue gas catalytic device, and the catalyst carrier is arranged in the grille. The catalyst carrier contacts with the flue gas to convert the flue gas into harmless gas, and the catalyst carrier can be replaced after loss or deactivation to ensure the efficiency of flue gas conversion, without open flame conversion, and improve the safety of equipment use.

[0007] Furthermore, the grille is arranged perpendicular to the flow direction of the smoke to reduce the flow resistance of the smoke.

[0008] Furthermore, it also includes a heating device, which is arranged in the air intake duct and is used to heat the flue gas to an optimal reaction temperature to improve the reaction efficiency.

[0009] Preferably, it also includes an air distribution pipe, which is arranged in the air intake duct and behind the heating device, and is used to inhale air and mix it into the flue gas to increase the oxygen of the reaction.

[0010] Preferably, it further comprises an air valve, which is arranged on the air distribution pipe and has an adjustable opening for adjusting the oxygen content of the mixed gas.

[0011] More preferably, the first combustion chamber also includes a temperature sensor, a first oxygen sensor and a second oxygen sensor. The temperature sensor and the first oxygen sensor are arranged in the first combustion chamber near one end of the first combustion chamber, and the second oxygen sensor is arranged in the first combustion chamber near the other end of the first combustion chamber, for accurately controlling the temperature and oxygen concentration of the flue gas undergoing the reaction, ensuring that the reaction proceeds continuously and stably, and preventing explosion due to excessive oxygen concentration.

[0012] As a more preferred embodiment, an exhaust fan is further included, and the exhaust fan is connected to the exhaust duct to increase the power of smoke flow so that the smoke can be discharged smoothly to the outside.

[0013] Preferably, it also includes a first valve, a second valve and a third valve, wherein the first valve is arranged between the intake pipe and the exhaust pipe, the first valve is connected in parallel with the first combustion chamber, the second valve is arranged at one end of the first combustion chamber, and the third valve is arranged at the other end of the first combustion chamber, and a branch bypass method is adopted to facilitate maintenance of the first combustion chamber.

[0014] Preferably, it also includes a second combustion chamber, a second valve, a third valve, a fourth valve and a fifth valve. The first combustion chamber and the second combustion chamber are connected in parallel between the air intake pipe and the exhaust pipe. The second valve is arranged at one end of the first combustion chamber, the third valve is arranged at the other end of the first combustion chamber, the fourth valve is arranged at one end of the second combustion chamber, and the fifth valve is arranged at the other end of the second combustion chamber. This can increase the flow rate of flue gas that can be processed simultaneously, and the combustion chamber can be used separately, and maintenance can be carried out without stopping the kiln.

[0015] The second purpose of the present invention is to provide a flue gas treatment method, which solves the problem that the existing flue gas treatment equipment uses open flame combustion to remove harmful substances, which poses a threat to personal safety.

[0016] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention is as follows:

[0017] A flue gas treatment method comprises the following steps:

[0018] S1. Preheating flue gas: one end of the first combustion chamber is connected to an air intake duct, and the other end is connected to an exhaust duct. The flue gas passes through the air intake duct, and is heated to a set temperature by a heating device in the air intake duct;

[0019] S2, air distribution: the heated flue gas flows in the air intake duct, the air distribution duct in the air intake duct is opened to inject air into the air intake duct, and the flue gas and air are mixed and enter the first combustion chamber;

[0020] S3, catalysis: the flue gas catalytic device in the first combustion chamber catalytically converts the mixed gas;

[0021] S4. Continuous conversion: The first combustion chamber detects the oxygen content and temperature of the incoming mixed gas, as well as the oxygen content of the mixed gas after conversion, and controls the opening of the air distribution pipe to keep the oxygen content of the mixed gas before conversion within a certain range. The flue gas is converted through a reaction without open flame combustion, which has high safety and reduces energy consumption.

[0022] The beneficial effects of the present invention are:

[0023] (1) The roller kiln flue gas treatment equipment is provided with a flue gas catalytic device in the combustion chamber. A grille is provided on the flue gas catalytic device. A catalyst carrier is provided in the grille. A catalyst is provided on the catalyst carrier. After catalysis, the flue gas is smokelessly burned and converted into harmless gas for external discharge. The catalyst carrier is detachably inserted into the grille and can be quickly replaced after the catalyst fails, thereby ensuring the efficiency of flue gas treatment. The temperature of smokeless combustion is lower than that of open flame combustion, thereby eliminating the potential risk of deflagration caused by open flame combustion.

[0024] (2) The air intake duct of the roller kiln flue gas treatment equipment is equipped with a heating device and an air distribution duct. The heating device heats the flue gas by electric heating. The air distribution duct is provided with an adjustable valve. The flue gas is electrically heated to reach the conversion temperature. The air is mixed into the flue gas through the air distribution duct to control the oxygen content of the mixed gas, ensuring that the flue gas is converted in a smokeless combustion manner, reducing energy water pumps and lowering construction costs.

[0025] (3) The roller kiln flue gas treatment equipment is provided with two parallel flue gas branches between the air inlet duct and the exhaust duct. Combustion chambers are respectively arranged on the two branches, and valves are installed at both ends of the combustion chambers to expand the flue gas treatment flow. At the same time, the kiln can be repaired without stopping the machine by opening and closing the combustion chambers separately. With the detachable catalyst carrier, the production line can be guaranteed to operate around the clock. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A structural diagram of the roller kiln fume treatment equipment provided by the present invention;

[0027] Figure 2 A cross-sectional view of a flue gas catalytic device of a roller kiln flue gas treatment device provided by the present invention;

[0028] Figure 3 The system composition of the roller kiln flue gas treatment equipment provided by the present invention Figure 1 ;

[0029] Figure 4 The system composition of the roller kiln flue gas treatment equipment provided by the present invention Figure 2 .

[0030] Reference numerals:

[0031] 1. Intake duct; 2. First combustion chamber; 21. Temperature sensor; 22. First oxygen sensor; 23. Second oxygen sensor; 24. Second combustion chamber; 3. Flue gas catalytic device; 31. Grille; 32. Catalyst carrier; 4. Heating device; 5. Air valve; 6. Air distribution duct; 7. Exhaust duct; 8. First valve; 81. Second valve; 82. Third valve; 83. Fourth valve; 84. Fifth valve; 9. Exhaust fan. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] Embodiment 1

[0034] like Figure 1-Figure 4 As shown, this embodiment discloses a roller kiln flue gas treatment equipment, including an air intake duct 1, a first combustion chamber 2 and an exhaust duct 7, the air intake duct 1 is connected to one end of the first combustion chamber 2, the exhaust duct 7 is connected to the other end of the first combustion chamber 2, at least one flue gas catalytic device 3 is provided in the first combustion chamber 2, the flue gas catalytic device 3 is arranged in the first combustion chamber 2, the flue gas catalytic device 3 includes a grille 31 and a catalyst carrier 32, the catalyst carrier 32 is arranged in the grille 31, the grille 31 is arranged in the flue gas catalytic device 3, the catalyst carrier 32 is detachably mounted on the grille 31, and can be replaced one by one after the catalyst carrier 32 is worn or deactivated, and the catalyst carrier 32 is arranged along the direction of the flue gas flow, which increases the contact area between the flue gas and the catalyst carrier 32, thereby improving the catalytic reaction efficiency.

[0035] Among them, a catalyst is provided on the catalyst carrier 32, and the catalyst can promote the reaction of CO and oxygen and the reaction of nitride and oxidation, and convert CO and NO in the exhaust gas into harmless substances by reducing the reaction activation energy and increasing the reaction rate. The catalyst uses metal oxides or composite oxides as active components; in addition, the detachable catalyst carriers 32 are arranged tightly, and the catalyst carriers 32 can be inserted into the grid 31. A high bulk density flexible insulation material is arranged on the inner wall of the first combustion chamber 2, and a sealing structure is formed by pressing.

[0036] Preferably, the catalyst carrier 32 is configured in a honeycomb shape to further increase the contact area between the flue gas and the catalyst, thereby improving the catalytic reaction efficiency.

[0037] Furthermore, the grille 31 is arranged perpendicular to the flow direction of the flue gas, which can reduce the flow resistance of the flue gas and facilitate the insertion and installation of the catalyst carrier 32.

[0038] Furthermore, the flue gas catalytic device 3 is detachably arranged in the combustion chamber 2 , and the flue gas catalytic device 3 is inserted into the combustion chamber 2 from the top of the combustion chamber 2 , so as to facilitate the replacement and maintenance of the catalyst carrier 32 on the flue gas catalytic device 3 .

[0039] Preferably, a plurality of flue gas catalytic devices 3 are arranged at intervals along the flow direction of the flue gas to improve the conversion efficiency of the flue gas.

[0040] More preferably, the catalyst carriers 32 are arranged in a front-to-back array in a blade-like manner, and the flue gas passes through them one by one, and the catalytic reaction is gradually carried out while passing through. After a period of use, the performance of the catalyst carriers 32 in some grids 31 decreases, and their service life can be extended by changing their positions, or they can be replaced one by one to achieve the purpose of reducing the use cost.

[0041] Preferably, the diameter of the first combustion chamber 2 is 2-10 times the diameter of the intake duct 1 or the exhaust duct 7. The first combustion chamber 2 can be installed on the flue gas duct as a part of the duct, which reduces the manufacturing cost and installation difficulty, and can be used in the modification of the existing flue gas duct.

[0042] Furthermore, it also includes a heating device 4, which is arranged in the air intake duct 1 and is located at the front end of the flue gas entering the air intake duct 1. The heating device 4 plays a role in heating the flue gas to the reaction temperature. By controlling the temperature of the flue gas, it is ensured that the temperature of the flue gas is in the optimal reaction range when passing through the flue gas catalytic device 3, thereby ensuring the conversion efficiency of the flue gas. If the flue gas temperature is lower than 200°C, the flue gas is heated.

[0043] The heating device 4 is an electric heating element, which has the characteristics of no open flame, accurate temperature control and fast heating. More specifically, the heating device 4 is an electric heating wire or an electric heating rod.

[0044] Furthermore, it also includes an air distribution duct 6, which is arranged in the air intake duct 1 and behind the heating device 4. The air distribution duct 6 is in a negative pressure state. After opening, the external air can be directly introduced into the air intake duct 1 to mix with the flue gas, thereby providing oxygen for the reaction. When the oxygen concentration of the flue gas is sufficient for the reaction, the air distribution duct 6 can be completely closed.

[0045] Furthermore, it also includes an air valve 5, which is arranged on the air distribution pipe 6. The opening of the air valve 5 is adjustable, and the air valve 5 adopts.

[0046] Preferably, the first combustion chamber 2 further comprises a temperature sensor 21, a first oxygen sensor 22 and a second oxygen sensor 23. The temperature sensor 21 and the first oxygen sensor 22 are arranged in the first combustion chamber 2 at one end close to the first combustion chamber 2, and the second oxygen sensor 23 is arranged in the first combustion chamber 2 at the other end close to the first combustion chamber 2, for respectively detecting the reaction temperature of the flue gas and the oxygen concentration before and after the reaction. The amount of combustion-supporting air is adjusted by the opening of the air valve 5, so that after the low-oxygen or oxygen-free flue gas is mixed with the combustion-supporting air, the oxygen in the mixed gas is controlled to be maintained at a high concentration without generating open flame combustion. When the device 21 detects that the temperature of the mixed gas is lower than the complete combustion temperature, generally lower than 350°C, the electric heating device 4 increases the heating power to increase the flue gas temperature. When the tempered mixed flue gas passes through multiple groups of catalyst carriers 32, the oxygen in the gas undergoes a low-temperature redox reaction with harmful organic matter to generate carbon dioxide, water and nitrogen. The oxygen concentration in the flue gas after the reaction is detected by the second oxygen sensor 23. If the oxygen concentration is close to the lower limit (there is a risk of deflagration when the oxygen concentration is too low), the opening of the air valve 5 must be increased to increase the amount of combustion-supporting air to ensure that there is enough oxygen involved in the low-temperature combustion, so that the flue gas can be converted without open flames.

[0047] More preferably, it also includes an exhaust fan 9, which is connected to the exhaust duct 7. The exhaust fan 9 is used to actively discharge the converted flue gas to the outside, so as to control the terminal flue gas flow rate.

[0048] Embodiment 2

[0049] This embodiment also discloses a flue gas treatment method, which is implemented by a roller kiln flue gas treatment device and includes the following steps:

[0050] S1. Preheating flue gas: One end of the first combustion chamber 2 is connected to the air intake pipe 1, and the other end is connected to the exhaust pipe 7. The flue gas passes through the air intake pipe 1, and is heated to a set temperature by the heating device 4 in the air intake pipe 1;

[0051] S2, air distribution: the heated flue gas flows in the air intake duct 1, the air distribution duct 6 in the air intake duct 1 is opened to inject air into the air intake duct 1, and the flue gas and air are mixed and enter the first combustion chamber 2;

[0052] S3, catalysis: the flue gas catalytic device 3 in the first combustion chamber 2 catalytically converts the mixed gas;

[0053] S4. Continuous conversion: The first combustion chamber 2 detects the oxygen content and temperature of the incoming mixed gas, as well as the oxygen content of the mixed gas after conversion, and controls the opening of the air distribution pipe 6 to keep the oxygen content of the mixed gas before conversion within a certain range. The flue gas is treated in a non-open flame manner, the temperature of the flue gas conversion becomes lower, and under most working conditions, the flue gas does not need to be heated for conversion; the oxygen utilization rate is greatly improved, a small amount of air is distributed in the oxygen-free and low-oxygen atmosphere to assist combustion, and no air distribution is required in the aerobic environment; the pollutant removal efficiency is high and there is no secondary pollution caused by fuel combustion.

[0054] Embodiment 3

[0055] See also Figure 3 This embodiment also discloses a roller flue gas treatment system, which also includes a first valve 8, a second valve 81 and a third valve 82. The first valve 8 is arranged between the air intake duct 1 and the exhaust duct 7. The first valve 8 is connected in parallel with the first combustion chamber 2. The second valve 81 is arranged at one end of the first combustion chamber 2. The third valve 82 is arranged at the other end of the first combustion chamber 2. Considering the economic efficiency of use, the first combustion chamber 2 works in the form of a bypass pipeline. In normal operation, the bypass valve 16 is normally closed. When maintenance is required, the third valve 82 is opened to bypass the flue gas, and the first valve 8 and the second valve 81 before and after the first combustion chamber 2 are closed. Online maintenance is implemented, so that the kiln production line can be kept running without stopping, thereby improving the use efficiency of the kiln.

[0056] Embodiment 4

[0057] See also Figure 4 The present embodiment also discloses a roller flue gas treatment system, which also includes a second combustion chamber 24, a second valve 81, a third valve 82, a fourth valve 83 and a fifth valve 84. The first combustion chamber 2 has the same structure as the second combustion chamber 24. The first combustion chamber 2 and the second combustion chamber 24 are connected in parallel between the intake pipe 1 and the exhaust pipe 7. The second valve 81 is arranged at one end of the first combustion chamber 2, the third valve 82 is arranged at the other end of the first combustion chamber 2, the fourth valve 83 is arranged at one end of the second combustion chamber 24, and the fifth valve 84 is arranged at the other end of the second combustion chamber 24.

[0058] By arranging the first combustion chamber 2 and the second combustion chamber 24 in parallel, and coordinating the opening and closing of the second valve 81, the third valve 82, the fourth valve 83 and the fifth valve 84, the first combustion chamber 2 and the second combustion chamber 24 can work simultaneously to increase the processing flow of the flue gas, or they can work separately to play a redundant arrangement and reduce the role of failure, thereby ensuring the stable operation of the kiln. When one of them fails, it can be closed separately or the catalyst carrier 32 can be replaced.

[0059] According to the disclosure and teaching of the above description, those skilled in the art to which the present invention belongs may also change and modify the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and changes of the present invention should also fall within the protection scope of the claims of the present invention. In addition, although some specific terms are used in this specification, these terms are only for the convenience of description and do not constitute any limitation to the present invention.

Claims

1. A roller kiln fume treatment device, comprising an air intake duct (1), a first combustion chamber (2) and an exhaust duct (7), wherein the air intake duct (1) is connected to one end of the first combustion chamber (2), and the exhaust duct (7) is connected to the other end of the first combustion chamber (2), characterized in that: At least one flue gas catalytic device (3) is provided in the first combustion chamber (2); the flue gas catalytic device (3) is arranged in the first combustion chamber (2); the flue gas catalytic device (3) comprises a grille (31) and a catalyst carrier (32); the grille (31) is arranged in the flue gas catalytic device (3); and the catalyst carrier (32) is arranged in the grille (31).

2. The roller kiln fume treatment equipment according to claim 1 is characterized in that: The grille (31) is arranged perpendicular to the flow direction of the smoke.

3. The roller kiln fume treatment equipment according to claim 2 is characterized in that: It also comprises a heating device (4), wherein the heating device (4) is arranged in the air intake duct (1).

4. The roller kiln fume treatment equipment according to claim 3 is characterized in that: It also includes an air distribution pipe (6), wherein the air distribution pipe (6) is arranged in the air intake pipe (1), and the air distribution pipe (6) is arranged behind the heating device (4).

5. The roller kiln fume treatment equipment according to claim 4 is characterized in that: It also comprises an air valve (5), wherein the air valve (5) is arranged on the air distribution pipe (6), and the opening degree of the air valve (5) is adjustable.

6. The roller kiln fume treatment equipment according to claim 5, characterized in that: The first combustion chamber (2) further comprises a temperature sensor (21), a first oxygen sensor (22) and a second oxygen sensor (23); the temperature sensor (21) and the first oxygen sensor (22) are arranged in the first combustion chamber (2) at one end close to the first combustion chamber (2); and the second oxygen sensor (23) is arranged in the first combustion chamber (2) at the other end close to the first combustion chamber (2).

7. The roller kiln fume treatment equipment according to claim 6, characterized in that: It also comprises an exhaust fan (9), wherein the exhaust fan (9) is connected to the exhaust duct (7).

8. The roller kiln fume treatment equipment according to any one of claims 1 to 7, characterized in that: The invention also comprises a first valve (8), a second valve (81) and a third valve (82), wherein the first valve (8) is arranged between the intake pipe (1) and the exhaust pipe (7), the first valve (8) is connected in parallel with the first combustion chamber (2), the second valve (81) is arranged at one end of the first combustion chamber (2), and the third valve (82) is arranged at the other end of the first combustion chamber (2).

9. The roller kiln fume treatment equipment according to any one of claims 1 to 7, characterized in that: The invention also includes a second combustion chamber (24), a second valve (81), a third valve (82), a fourth valve (83) and a fifth valve (84); the first combustion chamber (2) and the second combustion chamber (24) are connected in parallel between the intake pipe (1) and the exhaust pipe (7); the second valve (81) is arranged at one end of the first combustion chamber (2); the third valve (82) is arranged at the other end of the first combustion chamber (2); the fourth valve (83) is arranged at one end of the second combustion chamber 24; and the fifth valve (84) is arranged at the other end of the second combustion chamber (24).

10. A flue gas treatment method, characterized in that: The following steps are involved: S1. Preheating flue gas: one end of the first combustion chamber (2) is connected to the air intake pipe (1), and the other end is connected to the exhaust pipe (7); the flue gas passes through the air intake pipe (1), and is heated to a set temperature by a heating device (4) in the air intake pipe (1); S2, air distribution: the heated flue gas flows in the air intake duct (1), the air distribution duct (6) in the air intake duct (1) is opened to inject air into the air intake duct (1), and the flue gas and air are mixed and enter the first combustion chamber (2); S3, catalysis: the flue gas catalytic device (3) in the first combustion chamber (2) catalytically converts the mixed gas; S4, continuous conversion: the first combustion chamber (2) detects the oxygen content and temperature of the incoming mixed gas, as well as the oxygen content of the mixed gas after conversion, and controls the opening of the air distribution pipe (6) so that the oxygen content of the mixed gas before conversion is within a certain range.

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