Desulfurization, denitration, dioxin removal and dust removal equipment for waste incineration flue gas

Abstract

The utility model belongs to the technical field of air pollutant treatment, particularly relates to desulfurization, denitrification, dioxin removal and dust removal equipment for waste incineration flue gas, and provides the following scheme aiming at the problems of complex components and high purification difficulty of the existing waste incineration flue gas: the desulfurization, denitrification, dioxin removal and dust removal equipment comprises an ultralow-temperature SCR (Selective Catalytic Reduction) denitrification system, a dust remover, a deacidification tower, a chimney and a fan, flue gas firstly passes through the deacidification tower, then enters the dust remover, then is introduced into the ultralow-temperature SCR denitration system, and finally is blown into the chimney through the fan to be discharged into the atmosphere. The deacidification tower is arranged at the front end of the dust remover and is used for carrying out desulfurization, deacidification and dioxin removal operations on the flue gas and removing hydrogen chloride and hydrogen fluoride in the flue gas; according to the desulfurization, denitrification, dioxin removal and dust removal equipment for the waste incineration flue gas, the waste incineration flue gas can be denitrified without heat compensation and temperature rise, and the operation economical efficiency of an environment-friendly system is improved while the stricter emission standard of main atmospheric pollutants of the waste incineration flue gas is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of air pollutant treatment, in particular to a garbage incineration flue gas desulfurization, denitration, dedioxin and dust removal device. Background Art

[0002] At present, waste incineration power plants have low flue gas temperature in the furnace and small high-temperature area, which leads to slow SNCR denitrification reaction and low efficiency, resulting in large ammonia consumption, low economic efficiency, and a large amount of ammonia escape, which corrodes equipment and causes secondary pollution. At present, the emission standards of atmospheric pollutants for waste incineration power plants in various provinces are becoming increasingly stringent. The SNCR denitrification process commonly used in waste incineration power plants is difficult to meet more stringent standards. In order to meet policy requirements, waste incineration power plants have tried many flue gas treatment technologies, including oxidation method and semi-dry method, wet desulfurization combination and medium and low temperature SCR denitrification technology. Among them, the oxidation method will produce more difficult-to-treat denitrification wastewater and denitrification solid waste. The lower limit of flue gas temperature of medium and low temperature SCR denitrification technology is 180℃, and due to the characteristics of waste incineration flue gas, such as high dust viscosity, many and mixed acidic gases, the SCR denitrification system is generally located after deacidification and dust removal. If semi-dry deacidification is used, the flue gas temperature after deacidification and dust removal is below 140℃. If wet deacidification is used, the flue gas temperature after dust removal and deacidification is <65℃. After that, the SCR denitrification system is installed, and the flue gas must be heated. The steam SGH is coupled with the GGH for heating, and the steam consumption is large, and the operating cost is high. At the same time, since the water content in the flue gas of the waste incineration plant is much higher than other industrial waste gases (>20%), and the flue gas contains difficult-to-treat organic matter such as dioxins, it will cause great challenges to the operation of the SCR denitrification equipment. Therefore, the desulfurization, denitrification, de-dioxin and dust removal process system for waste incineration flue gas needs to be developed urgently to ensure that the equipment operates stably and produces as little wastewater and solid waste as possible during the flue gas treatment process. Utility Model Content

[0003] The utility model aims to solve the shortcomings of the prior art in the complex composition and great difficulty in purifying the flue gas from garbage incineration, and proposes a desulfurization, denitrification, dedioxin and dust removal device for the flue gas from garbage incineration.

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

[0005] A waste incineration flue gas desulfurization, denitration, de-dioxin and dust removal equipment, including an ultra-low temperature SCR denitration system, a dust collector, a deacidification tower, a chimney and a fan;

[0006] The flue gas flows through the deacidification tower first, then enters the dust collector, and then enters the ultra-low temperature SCR denitrification system. Finally, the flue gas is blown into the chimney by the fan and discharged into the atmosphere;

[0007] The deacidification tower is arranged at the front end of the dust collector to perform desulfurization, deacidification and dioxin removal on the flue gas, and remove hydrogen chloride and hydrogen fluoride in the flue gas;

[0008] The ultra-low temperature SCR denitration system includes 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;

[0009] The high-energy particle classification distribution system and the ultra-low temperature SCR catalyst are installed in the denitration reaction tower.

[0010] Preferably, the deacidification tower is a semi-dry deacidification tower using lime slurry, and activated carbon powder is sprayed into the deacidification tower to complete the adsorption of dioxins.

[0011] Preferably, the dust collector adopts bag dust removal and is arranged before the ultra-low temperature SCR denitrification system to filter the dust in the flue gas.

[0012] Preferably, the gas purification system is used to dehumidify the external air, purify impurities, filter dust, etc.

[0013] Preferably, 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.

[0014] 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.

[0015] 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.

[0016] 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.

[0017] 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.

[0018] 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 7 and the operating power of the particle charging system in real time according to the flue gas flow and the nitrogen oxide concentration.

[0019] The utility model relates to the field of air pollutant treatment, specifically a waste incineration flue gas desulfurization, denitration, de-dioxin and dust removal equipment, including an ultra-low temperature SCR denitration system, a dust collector, a deacidification tower and a chimney. The ultra-low temperature SCR denitration system is composed of 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 ascending flue and an exhaust flue.

[0020] The flue gas from garbage incineration is first passed into a deacidification tower to complete desulfurization, deacidification, and dioxin removal operations. The dust collector is connected at the outlet. The treated flue gas is passed into the dust collector to filter out dust. The filtered flue gas is passed into the ultra-low temperature SCR denitrification system. The ammonia injection system is installed inside the ascending flue. The instrument control system controls the amount of ammonia injection and the power of the particle charging system according to the detected flue gas flow and nitrogen oxide concentration. The flue gas enters the system through the ascending flue, and the ammonia injection system sprays ammonia into the ascending flue to fully mix it with the flue gas. The flue gas flows through the ascending flue to the upper end of the denitrification reaction tower, where a high-energy particle grading distribution system is installed. The high-energy particle grading distribution system sprays high-energy particles containing oxygen free radicals and singlet oxygen generated after dehumidification, impurity purification, dust filtration and particle 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 relatively low temperature to generate N2 and H2O, completing the denitrification process. The denitrified flue gas is blown into the chimney by a fan and discharged into the atmosphere.

[0021] In the utility model, a garbage incineration flue gas desulfurization, denitrification, de-dioxin and dust removal equipment can realize the denitrification of garbage incineration flue gas without heat supplement and temperature increase, and improve the economic efficiency of environmental protection system operation while achieving stricter emission standards for major air pollutants in garbage incineration flue gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the process of a garbage incineration flue gas desulfurization, denitrification, de-dioxin and dust removal equipment proposed by the utility model;

[0023] Figure 2 This is a schematic diagram of the overall structure of an ultra-low temperature SCR denitrification system for a waste incineration flue gas desulfurization, denitrification, dioxin and dust removal device proposed by the utility model.

[0024] In the figure: 1. Deacidification tower; 2. Dust collector; 3. Ultra-low temperature SCR denitrification system; 4. Fan; 5. Chimney; 6. Upstream flue; 7. Ammonia injection system; 8. Gas purification system; 9. Instrument control system; 10. High-energy particle classification distribution system; 11. Ultra-low temperature SCR catalyst; 12. Exhaust flue; 13. Denitrification reaction tower; 14. Particle charging system. DETAILED DESCRIPTION

[0025] 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.

[0026] Example 1

[0027] This plan is explained using the flue gas from a garbage incineration as an example. The specific plan is as follows:

[0028] The waste incineration flue gas desulfurization, denitrification, de-dioxin and dust removal equipment is composed of an ultra-low temperature SCR denitrification system 3, a dust collector 2, a deacidification tower 1, a fan 4 and a chimney 5.

[0029] The flue gas generated by the incineration of garbage flows through the semi-dry deacidification tower 1, the bag filter 2, the ultra-low temperature SCR denitrification system 3 in sequence, and finally blown into the chimney 5 through the fan 4 and discharged into the atmosphere.

[0030] The deacidification tower 1 is a semi-dry deacidification tower using lime slurry.

[0031] The ultra-low temperature SCR denitration system 3 is composed of a gas purification system 8, a particle charging system 14, a high-energy particle graded distribution system 10, an instrument control system 9, an ultra-low temperature SCR catalyst 11, a denitration reaction tower 13, an ammonia injection system 7, an ascending flue 6, and an exhaust flue 12. The gas purification system 8 is connected to the particle charging system 14. The two systems are installed near the denitration reaction tower 13 and can be arranged in multiple layers. The high-energy particle graded distribution system 10 is arranged at the upper end of the denitration reaction tower 13, and the ultra-low temperature SCR catalyst 11 is arranged below the high-energy particle graded distribution system 10. The instrument control system 9 includes flue gas flow detection and nitrogen oxide concentration detection.

[0032] During the operation of the system, the waste incineration flue gas is passed into the semi-dry deacidification tower 1 to complete the desulfurization, deacidification and dioxin removal operations, reducing the sulfur dioxide content in the flue gas to below 35 mg, and removing hydrogen chloride, hydrogen fluoride and dioxins. The treated flue gas is passed into the bag filter 2 to reduce the dust concentration in the flue gas to below 10 mg. The dust-removed flue gas is passed into the ultra-low temperature SCR denitrification system 3. Inside the ultra-low temperature SCR denitration system 3, ammonia is sprayed into the ascending flue 6 through the ammonia spraying system 7 to mix with the flue gas, and the air is purified by the gas purification system 8 and then passed into the particle charging system 14. After the high-energy particles are generated, they are sent to the high-energy particle classification distribution system 10 through a pipeline and then sprayed into the flue gas. The instrument control system 9 controls the ammonia spraying amount of the ammonia spraying system 7 and the power of the particle charging system 14 according to the flue gas flow rate and the nitrogen oxide concentration. The ammonia and high-energy particles sprayed into the flue gas react with the nitrogen oxides in the flue gas on the catalyst surface with the help of the ultra-low temperature SCR catalyst 11 to generate N2 and H2O, and the nitrogen oxide concentration in the flue gas is reduced to less than 50 mg. The flue gas after denitration is discharged through the lower exhaust flue 12 of the denitration reaction tower 13, and then the flue gas is blown into the chimney 5 through the fan 4 and discharged into the atmosphere.

[0033] Based on the above principles, the connection relationship of the structural components of this technical solution is:

[0034] The equipment is mainly composed of a deacidification tower 1, a dust collector 2, an ultra-low temperature SCR denitration system 3, a fan 4 and a chimney 5. Among them, the ultra-low temperature SCR denitration system 3 is further subdivided into a gas purification system 8, a particle charging system 14, a high-energy particle classification distribution system 10, an instrument control system 9, an ultra-low temperature SCR catalyst 11, a denitration reaction tower 13, an ammonia injection system 7, an ascending flue 6 and an exhaust flue 12.

[0035] Deacidification tower 1: It uses semi-dry deacidification technology and lime slurry as a desulfurizer. During the deacidification process, activated carbon powder is sprayed into the tower to absorb dioxins in the flue gas and remove acidic gases such as hydrogen chloride and hydrogen fluoride.

[0036] Dust collector 2: Located between the deacidification tower 1 and the ultra-low temperature SCR denitrification system 3, it adopts bag dust removal technology to effectively filter dust in the flue gas.

[0037] The ultra-low temperature SCR denitration system 3 includes the following components:

[0038] Gas purification system 8: responsible for dehumidifying, purifying impurities and filtering dust from external air, and providing a pure gas source for the particle charging system 14. The gas purification system 8 includes dehumidification particles and gas separation fillers. The dehumidification particles are used to cool the air and dehumidify the air, and the gas separation fillers are used to cool the air and purify impurities in the air, such as argon.

[0039] Particle charging system 14: converts the pure gas output by gas purification system 8 into high-energy particles containing oxygen free radicals and singlet oxygen, etc. Particle charging system 14 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.

[0040] High-energy particle classification distribution system 10: installed at the upper end of the denitration reaction tower 13, used to spray high-energy particles into the flue gas uniformly and quantitatively to ensure that they are fully mixed with the flue gas. The high-energy particle classification distribution system 10 consists 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 then sprayed into the flue gas through the nozzle.

[0041] Ultra-low temperature SCR catalyst 11: Installed at the lower end of the high-energy particle classification distribution system 10, it allows the high-energy particles fully mixed with the flue gas to react with ammonia. The catalyst converts NH3 molecules into -NH2 groups, which are used to capture NOx molecules in the flue gas and form NH2-M-NO intermediates.

[0042] Denitration reaction tower 13: An ultra-low temperature SCR catalyst 11 and a high-energy particle classification distribution system 10 are installed inside, and it is the main place for the denitration reaction.

[0043] Ammonia injection system 7: installed inside the ascending flue 6, controls the amount of ammonia injection according to the instructions of the instrument control system 9 to ensure that ammonia and nitrogen oxides in the flue gas are fully mixed in a certain proportion.

[0044] Fan 4: responsible for blowing the treated flue gas into the chimney 5.

[0045] Chimney 5: serves as a flue gas discharge channel to discharge the treated flue gas into the atmosphere.

[0046] 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 waste incineration flue gas desulfurization, denitrification, de-dioxin and dust removal equipment, characterized in that: It includes an ultra-low temperature SCR denitration system (3), a dust collector (2), a deacidification tower (1), a chimney (5), and a fan (4); The flue gas first flows through the deacidification tower (1), then enters the dust collector (2), and then enters the ultra-low temperature SCR denitrification system (3). Finally, the flue gas is blown into the chimney (5) through the fan (4) and discharged into the atmosphere; The deacidification tower (1) is arranged at the front end of the dust collector (2) to perform desulfurization, deacidification and dioxin removal on the flue gas, and remove hydrogen chloride and hydrogen fluoride in the flue gas; The ultra-low temperature SCR denitration system (3) comprises a gas purification system (8), a particle charging system (14), a high-energy particle classification distribution system (10), an instrument control system (9), an ultra-low temperature SCR catalyst (11), a denitration reaction tower (13), an ammonia injection system (7), an ascending flue (6), and an exhaust flue (12); The high-energy particle classification distribution system (10) and the ultra-low temperature SCR catalyst (11) are installed in a denitration reaction tower (13).

2. The waste incineration flue gas desulfurization, denitrification, de-dioxin and dust removal equipment according to claim 1, characterized in that: The deacidification tower (1) is a semi-dry deacidification tower using lime slurry. Activated carbon powder is sprayed into the deacidification tower (1) to adsorb dioxins.

3. The waste incineration flue gas desulfurization, denitrification, de-dioxin and dust removal equipment according to claim 1, characterized in that: The dust collector (2) uses bag dust removal and is arranged before the ultra-low temperature SCR denitration system (3) to filter dust in the flue gas.

4. The waste incineration flue gas desulfurization, denitrification, de-dioxin and dust removal equipment according to claim 1, characterized in that: The gas purification system (8) is used to dehumidify the external air, purify impurities, and filter dust.

5. The waste incineration flue gas desulfurization, denitrification, de-dioxin and dust removal equipment according to claim 1, characterized in that: The high-energy particle classification distribution system (10) is installed at the upper end of the denitration reaction tower (13) to fully mix the high-energy particles with the flue gas before the flue gas passes through the ultra-low temperature SCR catalyst (11).

6. The waste incineration flue gas desulfurization, denitrification, de-dioxin and dust removal equipment according to claim 1, characterized in that: The ultra-low temperature SCR catalyst (11) ensures that the flue gas can fully react with the catalyst. The ultra-low temperature SCR catalyst (11) is installed at the lower end of the high-energy particle classification distribution system (10) to ensure that the high-energy particles and ammonia that are fully mixed with the flue gas can initially react.

7. The waste incineration flue gas desulfurization, denitrification, de-dioxin and dust removal equipment according to claim 1, characterized in that: The ammonia injection system (7) is installed inside the ascending flue (6) 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.

8. The waste incineration flue gas desulfurization, denitrification, de-dioxin and dust removal equipment according to claim 1, characterized in that: The instrument control system (9) is composed of a flue gas flow detector and a nitrogen oxide concentration detector. The function of the instrument control system (9) is to adjust the ammonia injection amount of the ammonia injection system (7) and the operating power of the particle charging system (14) in real time according to the flue gas flow and the nitrogen oxide concentration.

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