Acid and dust removal device for electrolytic aluminum tail gas

Abstract

The utility model relates to the technical field of tail gas treatment, and discloses an electrolytic aluminum tail gas deacidification and dust removal device which comprises a gas inlet pipe, a slaked lime spraying device, a dust removal filter bag, a first fan and a gas exhaust pipe, one end of the air inlet pipe is connected with an external tail gas pipeline, the lime spraying device and the dust removal filter bag are sequentially arranged on the air inlet pipeline, the other end of the air inlet pipe is connected with the exhaust air pipe, and the first fan is arranged on the exhaust air pipe; wherein tail gas enters the lime spraying device through the gas inlet pipe to be subjected to acid removal, then is introduced into the dust removal filter bag to be subjected to dust removal, and is discharged from the exhaust air pipe under the suction action of the first fan. The tail gas treatment device has the beneficial effects that HCL and HF in tail gas can be absorbed to generate non-toxic and harmless reactants, and dust in the tail gas is absorbed at the same time, so that the emission of the treated tail gas reaches the national standard, and the environment is protected.

Description

Technical Field

[0001] The utility model relates to the technical field of tail gas treatment, in particular to a device for removing acid and dust from tail gas of electrolytic aluminum. Background Art

[0002] In recent years, electrolytic purification has been the core process for mass production of high-purity aluminum. However, dusty flue gas containing HCL and HF is usually produced during the purification process. HCL and HF gases are both acidic gases. Directly discharged into the atmosphere and combined with water will form acid rain (hydrochloric acid and hydrofluoric acid). Direct discharge of dust in the tail gas will also increase the PM2.5 content in the air and eventually form haze, affecting air quality. Therefore, in order to protect the environment and ensure that the exhaust gas emissions after treatment meet national standards, it is very important to design a suitable electrolytic aluminum tail gas treatment device. Utility Model Content

[0003] The purpose of the utility model is to provide an electrolytic aluminum tail gas acid and dust removal device, which can absorb HCL and HF in the tail gas to generate non-toxic and harmless reactants, and absorb the dust in the tail gas at the same time, to ensure that the exhaust gas after treatment meets the national standards and protect the environment.

[0004] In order to achieve the above-mentioned purpose, the utility model provides an electrolytic aluminum tail gas acid removal and dust removal device, comprising an air intake pipe, a slaked lime spraying device, a dust removal filter bag, a first fan and an exhaust air duct;

[0005] One end of the air intake pipe is connected to the external exhaust pipe, the lime spraying device and the dust filter bag are arranged on the air intake pipe in sequence, and the other end of the air intake pipe is connected to the exhaust duct, and the exhaust duct is provided with the first fan;

[0006] Among them, the exhaust gas enters the lime spraying device through the air inlet pipe for acid removal, passes into the dust removal filter bag for dust removal, and is discharged from the exhaust duct under the suction force of the first fan.

[0007] Furthermore, the slaked lime spraying device includes a first pump body, a first pipe, a slaked lime storage chamber, a second pipe, a second pump body, and a nozzle. One end of the first pipe is connected to the slaked lime storage chamber, and the other end is connected to an external slaked lime supply device. The first pump body is located in the first pipe and is used to transport liquefied slaked lime to the slaked lime storage chamber through the first pipe. One end of the second pipe is connected to the slaked lime storage chamber, and the other end is connected to the nozzle, and is used to transport the liquefied slaked lime in the slaked lime storage chamber to the nozzle for spraying the exhaust gas. The nozzle is located in the intake pipe.

[0008] Furthermore, a sedimentation chamber is provided at the bottom of the air inlet pipe, the sedimentation chamber is located directly below the nozzle, and a discharge port is provided below the sedimentation chamber.

[0009] Furthermore, the dust removal filter bag includes a filter bag body, a back-blow pulse valve, a waste collection bucket and a supporting foot. A plurality of back-blow pulse valves for connecting to the intake pipe are arranged above the filter bag body, the waste collection bucket is arranged at the lower end of the filter bag body, and the supporting foot is arranged below the waste collection bucket. The exhaust gas enters the filter bag body through the back-blow pulse valve for dust removal, and the waste collection bucket is used to collect dust impurities.

[0010] Furthermore, a coating and a film are provided inside the filter bag body.

[0011] Furthermore, the pressure of the filter bag body is less than 1300Pa.

[0012] Furthermore, a valve is provided at one end of the air intake pipe close to the external exhaust pipe.

[0013] Furthermore, a connecting flange is provided at the end of the air inlet pipe.

[0014] Compared with the prior art, the invention provides an electrolytic aluminum tail gas acid and dust removal device, which has the following beneficial effects: a slaked lime spray device and a dust removal filter bag are provided, and the tail gas enters the lime spray device through the air intake pipe for acid removal to generate non-toxic and harmless calcium chloride and fluorine chloride, which is beneficial to environmental protection, and the deacidified tail gas is passed into the dust removal filter bag for dust removal, and after acid and dust removal, the tail gas is discharged from the exhaust duct under the suction of the first fan, and the overall structure is simple, and the acid and dust removal treatment effect of the tail gas is better. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the structure of the electrolytic aluminum tail gas acid and dust removal device according to the embodiment of the utility model;

[0016] Figure 2 It is a structural schematic diagram of a slaked lime spraying device of an electrolytic aluminum tail gas acid removal and dust removal device according to an embodiment of the utility model;

[0017] Figure 3 It is a schematic diagram of the structure of the dust removal filter bag of the electrolytic aluminum tail gas acid removal and dust removal device according to the embodiment of the utility model;

[0018] Figure 4 It is a schematic diagram of the structure of the air intake pipe of the electrolytic aluminum tail gas acid and dust removal device according to the embodiment of the utility model.

[0019] In the figure, 1. air inlet pipe; 11. sedimentation chamber; 111. discharge port; 12. valve; 13. connecting flange; 14. plug; 2. slaked lime spraying device; 21. first pump body; 22. first pipeline; 23. slaked lime storage chamber; 24. second pipeline; 25. second pump body; 26. nozzle; 3. dust filter bag; 31. filter bag body; 32. back-blowing pulse valve; 33. waste collection barrel; 34. supporting foot; 4. first fan; 5. exhaust air duct. DETAILED DESCRIPTION

[0020] The following is a further detailed description of the specific implementation of the present invention in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0021] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "inside", "outside", etc. used in the present invention to indicate the orientation or positional relationship are based on the positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred devices and elements must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0022] In the description of the present invention, it should be understood that the terms "first", "second", etc. are used in the present invention to describe various information, but these information should not be limited to these terms, and these terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present invention, "first" information may also be referred to as "second" information, and similarly, "second" information may also be referred to as "first" information.

[0023] like Figure 1 As shown, a preferred embodiment of the utility model is an electrolytic aluminum tail gas acid removal and dust removal device, comprising an air intake pipe 1, a slaked lime spraying device 2, a dust removal filter bag 3, a first fan 4 and an exhaust air duct 5; Figure 1 One end of the air intake pipe 1 is connected to the external tail gas pipeline, and a lime spray device and a dust filter bag 3 are arranged on the air intake pipe 1 in sequence. The other end of the air intake pipe 1 is connected to the exhaust air duct 5, and a fan is arranged on the exhaust air duct 5. The working process is as follows: the tail gas enters the lime spray device through the air intake pipe 1 for acid removal, passes through the dust filter bag 3 for dust removal, and is discharged from the exhaust air duct 5 under the suction of the first fan 4. Among them, the slaked lime spray device 2 reacts with HCL and HF in the tail gas to generate non-toxic and harmless calcium chloride and fluorine chloride. The dust filter bag 3 is used to further remove dust from the tail gas after acid removal to meet the national emission standards and protect the environment.

[0024] In this embodiment, in order to facilitate the design of the slaked lime spraying device 2, refer to Figure 2 The slaked lime spraying device 2 includes a first pump body 21, a first pipe 22, a slaked lime storage chamber 23, a second pipe 24, a second pump body 25, and a nozzle 26, wherein one end of the first pipe 22 is connected to the slaked lime storage chamber 23, and the other end is connected to an external slaked lime supply device. The first pump body 21 is located in the first pipe 22, and is used to transport the liquefied slaked lime to the slaked lime storage chamber 23 through the first pipe 22. One end of the second pipe 24 is connected to the slaked lime storage chamber 23, and the other end is connected to the nozzle 26, and is used to transport the liquefied slaked lime in the slaked lime storage chamber 23 to the nozzle 26 for spraying the exhaust gas. The nozzle 26 is located in the intake pipe 1, and then reacts with HCL and HF in the exhaust gas. Furthermore, in order to facilitate the discharge of the generated calcium chloride, fluorine chloride and excess liquefied slaked lime, refer to Figure 4 A sedimentation chamber 11 is provided at the bottom of the air inlet pipe 1. The sedimentation chamber 11 is located directly below the nozzle 26. A discharge port 111 is provided below the sedimentation chamber 11. In order to facilitate the opening of the discharge port 111, a plug 14 is provided at the discharge port 111. When the waste in the sedimentation chamber 11 needs to be discharged, the plug 14 can be removed. The plug 14 is made of rubber material and can seal the discharge port 111 to prevent exhaust gas from overflowing.

[0025] Further, in this embodiment, refer to Figure 3 The dust filter bag 3 includes a filter bag body 31, a back-blowing pulse valve 32, a waste collection bucket 33 and a support foot 34. Specifically, a plurality of back-blowing pulse valves 32 for connecting with the air intake pipe 1 are arranged above the filter bag body 31, a waste collection bucket 33 is arranged at the lower end of the filter bag body 31, and a support foot 34 is arranged below the waste collection bucket. The exhaust gas enters the filter bag body 31 through the back-blowing pulse valve 32 for dust removal, and the waste collection bucket 33 is used to collect dust impurities. Furthermore, in order to improve the service life and anti-corrosion effect of the filter bag body 31, a coating and a film are arranged inside the filter bag body 31. Specifically, the filter bag body 31 is made of PTFE material. In this embodiment, the specifications of the dust filter bag 3 are 160mm in diameter*6000mm in length, and the corresponding specifications can be selected according to actual needs. During use, the dust removal filter bag 3 adopts a low-pressure pulse offline dust removal mode with a high dust removal efficiency. Furthermore, in order to make the dust removal filter bag 3 work stably, in this embodiment, the pressure of the filter bag body 31 is less than 1300Pa.

[0026] In this embodiment, in order to facilitate the control of the exhaust gas intake volume of the intake pipe 1, a valve 12 is provided at one end of the intake pipe 1 close to the external exhaust gas pipeline. By adjusting the opening of the valve 12, the exhaust gas treatment volume of the device is adjusted. Figure 1 A connecting flange 13 is provided at the end of the intake pipe 1.

[0027] In summary, the embodiment of the utility model provides an electrolytic aluminum tail gas acid removal and dust removal device, which is provided with a slaked lime spray device 2 and a dust removal filter bag 3. The tail gas enters the lime spray device through the air inlet pipe 1 for acid removal to generate non-toxic and harmless calcium chloride and fluorine chloride, which is beneficial to environmental protection. The tail gas after acid removal is passed into the dust removal filter bag 3 for dust removal. After acid removal and dust removal, the tail gas is discharged from the exhaust air duct 5 under the suction of the first fan 4. The overall structure is simple, and the acid removal and dust removal treatment effect of the tail gas is better.

[0028] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principle of the present invention. These improvements and substitutions should also be regarded as the protection scope of the present invention.

Claims

1. A device for removing acid and dust from electrolytic aluminum tail gas, characterized by: It includes an air intake pipe, a slaked lime spraying device, a dust filter bag, a first fan and an exhaust air duct; One end of the air intake pipe is connected to the external exhaust pipe, the lime spraying device and the dust filter bag are arranged on the air intake pipe in sequence, and the other end of the air intake pipe is connected to the exhaust duct, and the first fan is arranged on the exhaust duct; Among them, the exhaust gas enters the lime spraying device through the air inlet pipe for acid removal, passes into the dust removal filter bag for dust removal, and is discharged from the exhaust duct under the suction force of the first fan.

2. The device for removing acid and dust from electrolytic aluminum tail gas according to claim 1, characterized in that: The slaked lime spraying device includes a first pump body, a first pipeline, a slaked lime storage chamber, a second pipeline, a second pump body, and a nozzle. One end of the first pipeline is connected to the slaked lime storage chamber, and the other end is connected to an external slaked lime supply device. The first pump body is located in the first pipeline and is used to transport liquefied slaked lime to the slaked lime storage chamber through the first pipeline. One end of the second pipeline is connected to the slaked lime storage chamber, and the other end is connected to the nozzle, and is used to transport the liquefied slaked lime in the slaked lime storage chamber to the nozzle for spraying the exhaust gas. The nozzle is located in the intake pipe.

3. The device for removing acid and dust from electrolytic aluminum tail gas according to claim 2, characterized in that: A deposition chamber is provided at the bottom of the air inlet pipe, and the deposition chamber is located directly below the nozzle. A discharge port is provided below the deposition chamber.

4. The device for removing acid and dust from electrolytic aluminum tail gas according to claim 1, characterized in that: The dust removal filter bag includes a filter bag body, a back-blow pulse valve, a waste collection bucket and a supporting foot. A plurality of back-blow pulse valves for connecting to the intake pipe are arranged above the filter bag body, the waste collection bucket is arranged at the lower end of the filter bag body, and the supporting foot is arranged below the waste collection bucket. The exhaust gas enters the filter bag body through the back-blow pulse valve for dust removal, and the waste collection bucket is used to collect dust impurities.

5. The device for removing acid and dust from electrolytic aluminum tail gas as claimed in claim 4, characterized in that: A coating and a film are arranged inside the filter bag body.

6. The device for removing acid and dust from electrolytic aluminum tail gas according to claim 4, characterized in that: The pressure of the filter bag body is less than 1300Pa.

7. The device for removing acid and dust from electrolytic aluminum tail gas according to claim 1, characterized in that: A valve is arranged at one end of the air inlet pipe close to the external tail gas pipeline.

8. The device for removing acid and dust from electrolytic aluminum tail gas according to claim 1, characterized in that: A connecting flange is provided at the end of the air inlet pipe.

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