Flue gas ultralow-temperature SCR (Selective Catalytic Reduction) denitration equipment

Abstract

The utility model belongs to the technical field of atmospheric pollutant treatment, particularly relates to flue gas ultralow-temperature SCR (Selective Catalytic Reduction) denitration equipment, and aims to solve the problems that the existing desulfurized flue gas needs to be heated to over 180 DEG C, a large amount of fuel is consumed, the economical efficiency is poor, a large amount of carbon dioxide is discharged in the fuel combustion process, and the current low-carbon environmental protection policy is not met. According to the scheme, the system comprises a gas purification system, a particle energy charging system, a high-energy particle grading distribution system, an instrument control system, an ultralow-temperature SCR catalyst, a denitration reaction tower, an ammonia spraying system, an ascending flue and a gas outlet flue. The SCR denitration system has the advantages that flue gas can be denitrated with sulfur at a lower temperature, and carbon emission is reduced while the operation economical efficiency of the SCR denitration system is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of air pollutant treatment, in particular to a flue gas ultra-low temperature SCR denitration device. Background Art

[0002] The current SCR denitrification technology is divided into medium-high temperature SCR denitrification and medium-low temperature SCR denitrification. The flue gas of the medium-high temperature SCR denitrification process does not need to be desulfurized, and its denitrification reaction temperature is 300℃~420℃. The flue gas temperature produced by the general sintering machine and biomass incinerator is below 150℃, and the flue gas needs to be heated to above 300℃. The medium-low temperature SCR denitrification needs to be desulfurized. The flue gas temperature after the desulfurization process drops to 50℃~100℃, while the medium-low temperature SCR denitrification reaction temperature needs to be maintained above 180℃. The flue gas after desulfurization needs to be heated to above 180℃, and the flue gas needs to be heated, which consumes a lot of fuel and has poor economic efficiency. In addition, the fuel combustion process will emit a large amount of carbon dioxide, which is not in line with the current low-carbon environmental protection policy. The SCR denitrification process with a lower temperature needs to be developed urgently to reduce denitrification fuel consumption and carbon dioxide emissions. Utility Model Content

[0003] The purpose of the utility model is to solve the shortcomings of the prior art and to propose a flue gas ultra-low temperature SCR denitrification equipment, which can achieve sulfur-free denitrification of flue gas at a lower temperature, improve the operating economy of the SCR denitrification system and reduce carbon emissions.

[0004] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0005] A flue gas ultra-low temperature SCR denitration equipment, comprising a gas purification system, a particle charging system, a high-energy particle classification distribution system, an instrument control system and an ultra-low temperature SCR catalyst, a denitration reaction tower, an ammonia injection system, an ascending flue, and an exhaust flue;

[0006] The high-energy particle classification distribution system and the ultra-low temperature SCR catalyst are installed in the denitration reaction tower;

[0007] The gas purification system is used to dehumidify the external air, purify impurities, filter dust, etc.;

[0008] The particle charging system is used to convert the gas purified by the gas purification system into high-energy particles containing oxygen free radicals and singlet oxygen.

[0009] Preferably, the high-energy particle graded distribution system sprays high-energy particles into the flue gas uniformly and quantitatively while protecting the high-energy particles from energy annihilation.

[0010] Preferably, the high-energy particle classification distribution system is installed at the upper end of the denitration reaction tower to fully mix the high-energy particles with the flue gas before the flue gas passes through the ultra-low temperature SCR catalyst.

[0011] Preferably, the ultra-low temperature SCR catalyst is installed at the lower end of the high-energy particle graded distribution system to ensure that the flue gas can fully react with the catalyst, ensuring that the high-energy particles and ammonia that can be fully mixed with the flue gas initially react. The ultra-low temperature SCR catalyst converts NH3 molecules into -NH2 groups to capture NOx molecules in the flue gas to form NH2-M-NO intermediates.

[0012] Preferably, the ammonia injection system is installed inside the ascending flue, and its function is to control the amount of ammonia injection and to fully mix the ammonia and nitrogen oxides in the flue gas in a certain proportion.

[0013] Preferably, the instrument control system is composed of a flue gas flow detector and a nitrogen oxide concentration detector, and the function of the instrument control system is to adjust the ammonia injection amount of the ammonia injection system and the operating power of the particle charging system in real time according to the flue gas flow and the nitrogen oxide concentration.

[0014] The ammonia injection system is installed inside the ascending flue. The instrument control system controls the ammonia injection amount and the particle charging system power according to the detected flue gas flow and nitrogen oxide concentration. The flue gas enters the system through the ascending flue, and ammonia is sprayed into the ascending flue to fully mix with the nitrogen oxides in the flue gas. The flue gas flows to the upper end of the denitration reaction tower through the ascending flue, where a high-energy particle graded distribution system is installed. The high-energy particle graded distribution system sprays high-energy particles containing oxygen free radicals and singlet oxygen generated after dehumidification, impurity purification, dust filtration and particle charging system charging by the gas purification system into the flue gas, mixes with the flue gas, and then passes through a single or multi-layer ultra-low temperature SCR catalyst layer. Inside the catalyst layer, the high-energy particles mixed in the flue gas convert the NH3 molecules adsorbed on the catalyst surface into -NH2 groups, which are used to capture NOx molecules in the flue gas and form NH2-M-NO intermediates. The intermediates are thermally decomposed at a lower temperature to generate N2 and H2O, completing the denitration process. The flue gas after denitration is discharged into the atmosphere through the lower exhaust flue of the denitration reaction tower.

[0015] The utility model discloses a flue gas ultra-low temperature SCR denitration device, which can realize the denitration of flue gas with sulfur at a lower temperature, improves the operating economy of the SCR denitration system and reduces the technical effect of carbon emission. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a structural schematic diagram of a flue gas ultra-low temperature SCR denitrification device proposed by the utility model.

[0017] In the figure: 1. Upstream flue; 2. Ammonia injection system; 3. Gas purification system; 4. Instrument control system; 5. High-energy particle classification distribution system; 6. Ultra-low temperature SCR catalyst; 7. Exhaust flue; 8. Denitrification reaction tower; 9. Particle charging system. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0019] Example 1

[0020] This scheme is explained by taking a low-temperature flue gas containing nitrogen oxides and sulfur dioxide as an example. The flue gas temperature range is: ≤160℃. The specific scheme is as follows:

[0021] The flue gas ultra-low temperature SCR denitrification equipment consists of an ascending flue 1, an ammonia injection system 2, a gas purification system 3, a particle charging system 9, a high-energy particle classification distribution system 5, an ultra-low temperature SCR catalyst 6, an exhaust flue 7, a denitrification reaction tower 8, and an instrument control system 4.

[0022] The gas purification system 3 is connected to the particle charging system 9. The two systems are installed near the denitration reaction tower 8 and can be arranged in multiple layers. The high-energy particle classification distribution system 5 is arranged at the upper end of the denitration reaction tower 8, and the ultra-low temperature SCR catalyst 6 is arranged below the high-energy particle classification distribution system 5. The instrument control system 4 includes flue gas flow detection and nitrogen oxide concentration detection.

[0023] The flue gas enters the denitration reaction tower 8 through the ascending flue 1. The instrument control system 4 controls the ammonia spraying amount of the ammonia spraying system 2 and the power of the particle charging system 9 according to the flue gas flow rate and the concentration of nitrogen oxides. When the external flue gas enters the SCR denitration reaction tower 8 through the ascending flue 1, the ammonia spraying system 2 sprays ammonia gas, which is fully mixed with the flue gas. The mixed flue gas enters the upper end of the denitration reaction tower 8. The flue gas passes through the uppermost high-energy particle classification distribution system 5. Under the control of the instrument control system 4, the high-energy particles are uniformly and quantitatively sprayed into the flue gas, and mixed with the flue gas at the upper end of the denitration reaction tower 8. The mixed flue gas continues to flow downward, passes through the three-layer ultra-low temperature SCR denitration catalyst 6, and the high-energy particles mixed with the flue gas react with the ammonia in the flue gas on the catalyst surface, and react with the nitrogen oxides in the flue gas to generate N2 and H2O, completing the SCR denitration reaction process. The denitrated flue gas is discharged through the lower exhaust flue 7 of the SCR denitration reaction tower 8.

[0024] During the operation of the system, ammonia is prepared by the ammonia production device and then transported to the ammonia injection system 2. The gas purification system 3 purifies the air, and the treated gas is passed into the particle charging system 9 to generate high-energy particles and transmit them through pipelines to the high-energy particle grading distribution system 5, where their energy is prevented from being annihilated under the protection of the high-energy particle grading distribution system 5.

[0025] Based on the above principles, the various structural combinations of this embodiment are as follows:

[0026] like Figure 1 As shown, the flue gas ultra-low temperature SCR denitration equipment of this embodiment includes a gas purification system 3, a particle charging system 9, a high-energy particle classification distribution system 5, an instrument control system 4 and an ultra-low temperature SCR catalyst 6, a denitration reaction tower 8, an ammonia injection system 2, an ascending flue 1, and an exhaust flue 7;

[0027] The high-energy particle classification distribution system 5 and the ultra-low temperature SCR catalyst 6 are installed in the denitration reaction tower 8;

[0028] The gas purification system 3 is used to dehumidify the external air, purify impurities, filter dust, etc. The gas purification system 3 includes dehumidification particles and gas separation fillers. The dehumidification particles are used to cool the air and dehumidify the air. The gas separation fillers are used to cool the air and purify impurities in the air, such as argon.

[0029] The particle charging system 9 is used to convert the gas purified by the gas purification system 3 into high-energy particles containing oxygen free radicals and singlet oxygen. The particle charging system 9 includes a high-frequency high-voltage power supply and a discharge chamber. The gas passes through the discharge chamber to charge the high-frequency high-voltage power supply.

[0030] The high-energy particle grading distribution system 5 protects the high-energy particles from energy annihilation while spraying the high-energy particles into the flue gas uniformly and quantitatively. The high-energy particle grading distribution system 10 is composed of a main pipe, branch pipes, a header, a branch pipe, and a nozzle group. The high-energy particles are sequentially passed through the main pipe, branch pipes, a header, a branch pipe, and a nozzle group and sprayed into the flue gas through the nozzle.

[0031] The high-energy particle classification distribution system 5 is installed at the upper end of the denitration reaction tower 8 to fully mix the high-energy particles with the flue gas before the flue gas passes through the ultra-low temperature SCR catalyst 6 .

[0032] The ultra-low temperature SCR catalyst 6 ensures that the flue gas can fully react with the catalyst. The ultra-low temperature SCR catalyst 6 is installed at the lower end of the high-energy particle classification distribution system 5 to ensure that the high-energy particles and ammonia that can be fully mixed with the flue gas have a preliminary reaction. The ultra-low temperature SCR catalyst 6 converts NH3 molecules into -NH2 groups to capture NOx molecules in the flue gas and form NH2-M-NO intermediates.

[0033] The ammonia injection system 2 is installed inside the ascending flue 1, and its function is to control the amount of ammonia injection and to fully mix the ammonia with the nitrogen oxides in the flue gas in a certain proportion.

[0034] The instrument control system 4 is composed of a flue gas flow detector and a nitrogen oxide concentration detector. The function of the instrument control system 4 is to adjust the ammonia injection amount of the ammonia injection system 2 and the operating power of the particle charging system 9 in real time according to the flue gas flow and the nitrogen oxide concentration.

[0035] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A flue gas ultra-low temperature SCR denitrification equipment, characterized in that: It includes a gas purification system (3), a particle charging system (9), a high-energy particle classification distribution system (5), an instrument control system (4), an ultra-low temperature SCR catalyst (6), a denitration reaction tower (8), an ammonia injection system (2), an ascending flue (1), and an exhaust flue (7); The high-energy particle classification distribution system (5) and the ultra-low temperature SCR catalyst (6) are installed in a denitration reaction tower (8); The gas purification system (3) is used to dehumidify the external air, purify impurities, and filter dust.

2. The flue gas ultra-low temperature SCR denitration equipment according to claim 1, characterized in that: The high-energy particle classification distribution system (5) is installed at the upper end of the denitration reaction tower (8) to fully mix the high-energy particles with the flue gas before the flue gas passes through the ultra-low temperature SCR catalyst (6).

3. The flue gas ultra-low temperature SCR denitration equipment according to claim 1, characterized in that: The ultra-low temperature SCR catalyst (6) ensures that the flue gas can fully react with the catalyst. The ultra-low temperature SCR catalyst (6) is installed at the lower end of the high-energy particle classification distribution system (5) to ensure that the high-energy particles and ammonia that are fully mixed with the flue gas can initially react.

4. The flue gas ultra-low temperature SCR denitration equipment according to claim 1, characterized in that: The ammonia injection system (2) is installed inside the ascending flue (1) and its function is to control the amount of ammonia injection and to fully mix the ammonia with the nitrogen oxides in the flue gas in a certain proportion.

5. The flue gas ultra-low temperature SCR denitration equipment according to claim 1, characterized in that: The instrument control system (4) is composed of a flue gas flow detector and a nitrogen oxide concentration detector. The function of the instrument control system (4) is to adjust the ammonia injection amount of the ammonia injection system (2) and the operating power of the particle charging system (9) in real time according to the flue gas flow and the nitrogen oxide concentration.

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