Waste gas combustion denitrification system

Abstract

The utility model relates to the technical field of waste gas treatment, and in particular to a waste gas combustion denitration system, including a combustion furnace for burning waste gas, a first atomizing nozzle is arranged in the combustion furnace, the first atomizing nozzle has a first liquid inlet and a first gas inlet, the first liquid inlet is connected to an ammonia water pipeline, and the first gas inlet is connected to a first air pipeline and a combustion-supporting fluid pipeline through a pipeline. That is, the combustion-supporting fluid will enter the combustion furnace with the air to ensure the combustion efficiency of the waste gas, and at the same time, the ammonia water enters the combustion furnace in an atomized state through the first atomizing nozzle, and the atomized ammonia water droplets are evaporated to ammonia gas, and the ammonia gas is mixed with the gas in the combustion furnace, and reacts with the nitrogen oxides generated by the combustion of the waste gas at a high temperature to generate nitrogen gas, completing the denitration process. Therefore, the combustion denitration system can denitrate the waste gas combustion products, and compared with adding an SCR reactor, the combustion denitration system can reduce investment costs and reduce occupied space.

Description

Technical Field

[0001] The utility model relates to the technical field of waste gas treatment, in particular to a waste gas combustion denitration system. Background Art

[0002] Direct emission of waste gas will pollute the environment. The existing technology uses a combustion furnace to treat waste gas. However, nitrogen oxides will be produced during the combustion of waste gas, and a denitrification device needs to be added downstream of the combustion furnace. The commonly used denitrification device is the SCR reactor, which has a catalytic layer. The catalyst in the catalytic layer needs to be replaced every two years or so, and solid waste will also be generated. Using an SCR reactor for denitrification not only has a high investment cost, but also takes up a large space.

[0003] Therefore, there is an urgent need for a waste gas combustion denitrification system to solve the above problems. Utility Model Content

[0004] The utility model aims to provide a waste gas combustion denitration system, which can reduce investment costs and occupy less space while denitrifying waste gas combustion products.

[0005] To achieve this purpose, the utility model adopts the following technical solutions:

[0006] A waste gas combustion denitrification system is provided, comprising a combustion furnace, wherein the combustion furnace is used to burn waste gas, wherein a first atomizing nozzle is arranged in the combustion furnace, wherein the first atomizing nozzle has a first liquid inlet and a first gas inlet, wherein the first liquid inlet is connected to an ammonia water pipeline, and the first gas inlet is connected to a first air pipeline and a combustion-supporting fluid pipeline through a pipeline.

[0007] As a preferred solution of the waste gas combustion denitration system, the waste gas inlet of the combustion furnace is located upstream of the first atomizing nozzle, and the ignition device of the combustion furnace is located downstream of the first atomizing nozzle.

[0008] As a preferred solution of the exhaust gas combustion denitrification system, the first atomizing nozzle is located in the combustion section of the combustion furnace, and the exhaust gas flows vertically upward in the combustion section.

[0009] As a preferred solution of the waste gas combustion denitrification system, a second atomizing nozzle is arranged in the flue of the combustion furnace, and the second atomizing nozzle has a second liquid inlet and a second gas inlet. The second liquid inlet is connected to the ammonia water pipeline, and the second gas inlet is connected to the second air pipeline.

[0010] As a preferred solution of the exhaust gas combustion denitrification system, it also includes an ammonia water storage tank, and one end of the ammonia water pipeline is connected to the ammonia water storage tank.

[0011] As a preferred solution for the exhaust gas combustion denitrification system, a metering pump is provided on the ammonia water pipeline.

[0012] As a preferred solution of the exhaust gas combustion denitrification system, a first one-way valve and / or a first flow valve is provided on the ammonia water pipeline.

[0013] As a preferred solution of the exhaust gas combustion denitrification system, the ammonia water pipeline is connected to the first liquid inlet through a first branch, and the ammonia water pipeline is connected to the second liquid inlet through a second branch. A fourth flow valve is provided on the first branch, and a fifth flow valve is provided on the second branch.

[0014] As a preferred solution of the exhaust gas combustion denitration system, an air pump is provided on the first air pipeline and / or the second air pipeline.

[0015] As a preferred solution of the exhaust gas combustion denitration system, a flashback preventer is provided on the combustion-supporting fluid pipeline;

[0016] And / or, a second one-way valve is provided on the combustion-supporting fluid pipeline.

[0017] Beneficial effects of the utility model:

[0018] The utility model provides a waste gas combustion denitration system, including a combustion furnace for burning waste gas, a first atomizing nozzle is arranged in the combustion furnace, the first atomizing nozzle has a first liquid inlet and a first gas inlet, the first liquid inlet is connected to the ammonia water pipeline, and the first gas inlet is connected to the first air pipeline and the combustion-supporting fluid pipeline through the pipeline. That is, the combustion-supporting fluid will enter the combustion furnace with the air to ensure the combustion efficiency of the waste gas, and at the same time, the ammonia water enters the combustion furnace in an atomized state through the first atomizing nozzle, and the atomized ammonia water droplets are evaporated to ammonia gas, and the ammonia gas is mixed with the gas in the combustion furnace, and reacts with the nitrogen oxides generated by the combustion of the waste gas at high temperature to generate nitrogen gas, completing the denitration process. Therefore, the combustion denitration system can denitrate the waste gas combustion products, and compared with adding an SCR reactor, the combustion denitration system can reduce investment costs and reduce occupied space. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of the exhaust gas combustion denitration system provided by an embodiment of the utility model.

[0020] In the figure:

[0021] 1. Combustion furnace; 2. First atomizing nozzle; 3. Ammonia pipeline; 4. First air pipeline; 5. Combustion-supporting fluid pipeline; 6. Ammonia storage tank; 7. Ammonia input pipeline; 8. Water input pipeline; 9. Metering pump; 10. First non-return valve; 11. First flow valve; 12. Second flow valve; 13. Third flow valve; 14. Waste gas input pipeline; 15. Second atomizing nozzle; 16. Second air pipeline; 17. First branch; 18. Second branch. DETAILED DESCRIPTION

[0022] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and implementation methods. It is understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention are shown in the accompanying drawings, rather than all of them.

[0023] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0025] Direct discharge of waste gas will pollute the environment. The prior art uses a combustion furnace 1 to treat waste gas. However, nitrogen oxides will be produced during the combustion of waste gas, and a denitrification device needs to be added downstream of the combustion furnace 1. The commonly used denitrification device is an SCR reactor. A catalytic layer is arranged in the SCR reactor. The catalyst in the catalytic layer needs to be replaced every two years or so, and solid waste will also be generated. Using an SCR reactor for denitrification not only has a large investment cost, but also takes up a large space. In order to solve the above problems, the present embodiment provides a waste gas combustion denitrification system, which uses ammonia and nitrogen oxides to undergo an oxidation-reduction reaction at high temperature to achieve denitrification. The waste gas combustion denitrification system can reduce investment costs and occupy less space while denitrifying the waste gas combustion products.

[0026] like Figure 1 As shown, the exhaust gas combustion denitration system includes a combustion furnace 1 for burning exhaust gas, and optionally, the combustion furnace 1 is a direct-fired furnace. A first atomizing nozzle 2 is arranged in the combustion furnace 1, and the first atomizing nozzle 2 has a first liquid inlet and a first gas inlet, the first liquid inlet is connected to the ammonia water pipeline 3, and the first gas inlet is connected to the first air pipeline 4 and the combustion-supporting fluid pipeline 5 through a pipeline. Optionally, in this embodiment, the combustion-supporting fluid is natural gas, and of course other combustion-supporting gases or liquids can also be used, which is not limited here.

[0027] The combustion-supporting fluid will enter the combustion furnace 1 along with the air to ensure the combustion efficiency of the exhaust gas, and at the same time, the ammonia water enters the combustion furnace 1 in an atomized state through the first atomizing nozzle 2, and the atomized ammonia water droplets evaporate to ammonia gas, which mixes with the gas in the combustion furnace 1 and reacts with the nitrogen oxides generated by the combustion of the exhaust gas at high temperature to generate nitrogen gas, completing the denitration process. Therefore, the combustion denitration system can denitrate the exhaust gas combustion products, and compared with adding an SCR reactor, the combustion denitration system can reduce investment costs and reduce occupied space.

[0028] The reaction of ammonia and nitrogen oxides is as follows:

[0029] NO+2NH3=2N2+3H2O

[0030] NO2+4NH3+O2=3N2+6H2O

[0031] 4NO+4NH3+O2=4N2+6H2O

[0032] Preferably, the exhaust gas inlet of the combustion furnace 1 is located upstream of the first atomizing nozzle 2, and the ignition device of the combustion furnace 1 is located downstream of the first atomizing nozzle 2. That is, the exhaust gas first passes through the first atomizing nozzle 2 to mix with the air and the combustion-supporting fluid to ensure that the exhaust gas is fully mixed with the air and the combustion-supporting fluid, and then passes through the ignition device to ensure that the air and the combustion-supporting fluid play their full role and improve the combustion efficiency of the exhaust gas.

[0033] Preferably, the first atomizing nozzle 2 is located in the combustion section of the combustion furnace 1, and the exhaust gas flows vertically upward in the combustion section. That is, after the atomized droplets move upward for a certain distance, they will move downward or obliquely downward under the action of gravity, and the exhaust gas will move upward as a whole, realizing gas-liquid countercurrent, extending the contact time between the two, and ensuring that the denitration reaction is fully carried out.

[0034] In order to further improve the denitration efficiency, preferably, a second atomizing nozzle 15 is provided in the flue of the combustion furnace 1, and the second atomizing nozzle 15 has a second liquid inlet and a second gas inlet, the second liquid inlet is connected to the ammonia water pipeline 3, and the second gas inlet is connected to the second air pipeline 16. That is, a position for ammonia water atomization injection is also provided in the flue of the combustion furnace 1 to further denitrate the flue gas generated by the combustion of the exhaust gas.

[0035] Preferably, the exhaust gas combustion denitration system further comprises an ammonia water storage tank 6, one end of the ammonia water pipeline 3 is connected to the ammonia water storage tank 6, and the ammonia water storage tank 6 is used to store ammonia water that meets a preset concentration range.

[0036] Preferably, an ammonia water input pipeline 7 and a water input pipeline 8 are provided on the ammonia water storage tank 6, so as to input ammonia water and water into the ammonia water storage tank 6 and adjust the ammonia water to meet the preset concentration range. In this embodiment, the concentration of ammonia water is 5%. Optionally, a second flow valve 12 is provided on the ammonia water input pipeline 7, and a third flow valve 13 is provided on the water input pipeline 8, so as to accurately control the flow of ammonia water and water addition.

[0037] Preferably, a metering pump 9 is provided on the ammonia water pipeline 3 to provide power for the flow of ammonia water. Preferably, a first one-way valve 10 is provided on the ammonia water pipeline 3 to ensure the one-way flow of ammonia water. Optionally, a first flow valve 11 is also provided on the ammonia water pipeline 3 to control the flow of ammonia water.

[0038] In order to control the ratio of ammonia water sprayed at the first atomizing nozzle 2 and the second atomizing nozzle 15, preferably, the ammonia water pipeline 3 is connected to the first liquid inlet through the first branch 17, and the ammonia water pipeline 3 is connected to the second liquid inlet through the second branch 18. A fourth flow valve (not shown in the figure) is provided on the first branch 17, and a fifth flow valve (not shown in the figure) is provided on the second branch 18. In this embodiment, the flow rate of ammonia water in the first branch 17 and the second branch 18 is 3.75 kg / h.

[0039] Preferably, an air pump (not shown in the figure) is provided on the first air pipeline 4, and preferably, an air pump (not shown in the figure) is also provided on the second air pipeline 16 to ensure that the air has a certain pressure so that the ammonia water can achieve an atomization effect. In this embodiment, the preset flow rate of the air is 0.2m 3 / h, the preset pressure is 0.5MPa.

[0040] Preferably, a flashback arrester (not shown) is provided on the combustion-supporting fluid pipeline 5 to prevent flashback of the combustion-supporting fluid pipeline 5. The flashback arrester is an existing device and will not be described in detail here.

[0041] Preferably, a second one-way valve (not shown in the figure) is provided on the combustion-supporting fluid pipeline 5 to prevent high-pressure air from entering the combustion-supporting fluid pipeline 5 and ensure the stable one-way flow of the combustion-supporting fluid.

[0042] The waste gas combustion denitrification system does not require the addition of an SCR denitrification device. It only needs to purchase an ammonia water storage tank 6 with a capacity of 1 cubic meter, a metering pump 9 and an atomizing nozzle, etc., without the need to purchase large-scale equipment. At the same time, the combustion-supporting fluid is driven by 0.5MPa air to be sprayed into the combustion furnace 1, which can ensure that the waste gas burns more fully and saves combustion-supporting fuel. At the same time, the gas-liquid countercurrent design is beneficial to the denitrification reaction, so that nitrogen oxides and ammonia are fully in contact under high temperature conditions. There is no need to add a catalyst, thereby reducing the investment cost and operating cost of the equipment.

[0043] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. Waste gas combustion denitrification system, characterized in that: The invention comprises a combustion furnace (1), wherein the combustion furnace (1) is used for burning exhaust gas, wherein a first atomizing nozzle (2) is arranged in the combustion furnace (1), wherein the first atomizing nozzle (2) has a first liquid inlet and a first gas inlet, wherein the first liquid inlet is connected to an ammonia water pipeline (3), and the first gas inlet is connected to a first air pipeline (4) and a combustion-supporting fluid pipeline (5) through a pipeline.

2. The exhaust gas combustion denitrification system according to claim 1, characterized in that: The exhaust gas inlet of the combustion furnace (1) is located upstream of the first atomizing nozzle (2), and the ignition device of the combustion furnace (1) is located downstream of the first atomizing nozzle (2).

3. The exhaust gas combustion denitrification system according to claim 1, characterized in that: The first atomizing nozzle (2) is located in the combustion section of the combustion furnace (1), and the exhaust gas flows vertically upward in the combustion section.

4. The exhaust gas combustion denitrification system according to claim 1, characterized in that: A second atomizing nozzle (15) is arranged in the flue of the combustion furnace (1), and the second atomizing nozzle (15) has a second liquid inlet and a second gas inlet, the second liquid inlet is connected to the ammonia water pipeline (3), and the second gas inlet is connected to the second air pipeline (16).

5. The exhaust gas combustion denitration system according to any one of claims 1 to 4, characterized in that: It also includes an ammonia water storage tank (6), and one end of the ammonia water pipeline (3) is connected to the ammonia water storage tank (6).

6. The exhaust gas combustion denitration system according to any one of claims 1 to 4, characterized in that: A metering pump (9) is provided on the ammonia water pipeline (3).

7. The exhaust gas combustion denitration system according to any one of claims 1 to 4, characterized in that: The ammonia water pipeline (3) is provided with a first one-way valve (10) and / or a first flow valve (11).

8. The exhaust gas combustion denitration system according to claim 4, characterized in that: The ammonia water pipeline (3) is connected to the first liquid inlet via a first branch (17), and the ammonia water pipeline (3) is connected to the second liquid inlet via a second branch (18). A fourth flow valve is provided on the first branch (17), and a fifth flow valve is provided on the second branch (18).

9. The exhaust gas combustion denitrification system according to claim 4, characterized in that: An air pump is provided on the first air pipeline (4) and / or the second air pipeline (16).

10. The exhaust gas combustion denitration system according to any one of claims 1 to 4, characterized in that: The combustion-supporting fluid pipeline (5) is provided with a flashback arrester; And / or, a second one-way valve is provided on the combustion-supporting fluid pipeline (5).

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