Partitioned ozone denitration reactor

Abstract

The utility model discloses a zoned ozone denitration reactor, which comprises a transversely arranged shell, a reactor inlet and a reactor outlet, the reactor inlet and the reactor outlet are positioned on two sides of the shell, the shell is cylindrical, at least two sections of oxidation zones are arranged in the shell, and a plurality of ozone spray guns are uniformly arranged on the shell corresponding to each section of oxidation zone along the radial direction. And a turbulent flow device for mixing flue gas and ozone to generate turbulent flow is arranged between every two sections of oxidation subareas. According to the utility model, the problem of low efficiency of NOx oxidation by ozone can be solved, and the problems of overflow waste of ozone, poor mixing effect of ozone and flue gas and long mixing stroke space can be avoided through the design of the ozone spray gun and the turbulent flow device.

Description

Technical Field

[0001] The utility model belongs to the technical field of gas purification, in particular to a partitioned ozone denitration reactor. Background Art

[0002] my country's nitrogen oxide emissions are among the highest in the world. The resulting air pollution is very serious, with huge economic losses, and has become the main factor restricting the sustainable development of my country's economy and society. Therefore, it is imperative to control nitrogen oxide pollution. Nitrogen oxides in the atmosphere mainly come from the use of fossil fuels. Among all nitrogen oxides emitted from fuel combustion, 70% come from direct combustion of coal. Fixed sources are the main source of nitrogen oxide emissions.

[0003] At present, mature denitrification processes include low-nitrogen combustion system, selective catalytic reduction (SCR), selective non-catalytic reduction (SNCR), ozone denitrification and other processes. Each process has its own advantages and disadvantages and applicable conditions. For large coal-fired boilers, the best technical means is selective catalytic reduction (SCR). For waste incineration, cement kilns and circulating fluidized bed boilers (CFB), selective non-catalytic reduction (SNCR) is a relatively economical process. In addition, there are many units that are neither suitable for SCR nor SNCR, and ozone oxidation denitrification is just suitable for such units.

[0004] As a new flue gas denitrification process, ozone oxidation has been rapidly promoted and applied in the flue gas denitrification industry in recent years. Ozone denitrification mainly uses the strong oxidizing property of ozone to convert low-valent NO x Oxides are oxidized to high-valent NO that is soluble in water x , high-valence NO x After dissolving in water, nitrite and nitrate are generated, which are neutralized and absorbed by the scrubbing tower, thus achieving the purpose of denitrification. Ozone oxidation denitrification technology solves many problems in traditional boiler processes. In itself, this technology does not require modification of the boiler and its ancillary facilities, does not require replacement of the fan, does not need to consider resistance, and does not require shutdown to affect production. It only needs to be added at a suitable position between the fan and the desulfurization tower. Compared with other technologies, it requires less investment, simple process, and simple installation and operation. Ozone removal of nitrogen oxides is a low-temperature system and does not require a higher temperature window like SCR and SNCR systems. The ozone generator can be used to remove NO in the flue gas during the production process. x Regardless of the fluctuation of flue gas flow or nitrogen oxide content, the ozone generation system can respond online in a timely manner, saving energy while controlling the emission of nitrogen oxides in the clean flue gas.

[0005] For example, the application publication number is CN105854554A, and the application publication time is August 18, 2016. It discloses an ozone low-temperature oxidation denitrification process and system, including a flue, an ozone generator, and a scrubber. An ozone distributor is installed in the flue, and ozone is sprayed into the flue through the ozone distributor. The ozone and flue gas mixed gas in the flue enters the scrubber, wherein the ozone distributor is composed of a plurality of ozone injection units to form a grid-like structure. The above-mentioned prior art is mainly to promote the mixing of ozone and flue gas, but there is still ozone leakage and waste, the mixing effect of ozone and flue gas is poor, the mixing stroke space is long, and ozone oxidation NO x The efficiency is low and the control effect of ozone dosage is poor.

[0006] Therefore, in order to further improve the economic efficiency of ozone denitrification, it is currently necessary to find technical means that can reduce the amount of ozone used while maintaining a high denitrification efficiency, promote the rapid dispersion of ozone, and make the ozone oxidizer more adaptable. Utility Model Content

[0007] The utility model provides a partitioned ozone denitrification reactor to solve the problem of NO x The degree of oxidation is not high, the ozone dosage control effect is poor, and at the same time, ozone escape is avoided, ozone loss is reduced to reduce costs, and the mixing effect of ozone and flue gas is poor, and the mixing stroke space is long, so as to achieve full and rapid oxidation of pollutants such as NO and improve the economy of ozone denitrification.

[0008] The technical solution of the utility model is as follows:

[0009] A zoned ozone denitrification reactor comprises a transversely arranged shell and a reactor inlet and a reactor outlet located on both sides of the shell. The shell is cylindrical and at least two oxidation zones are arranged inside the shell. A plurality of ozone spray guns are evenly arranged radially on the shell corresponding to each oxidation zone, and a turbulent device for mixing flue gas and ozone to generate turbulence is arranged between every two oxidation zones.

[0010] Furthermore, an ozone main pipe and several ozone annular branch pipes are arranged outside the shell, and all ozone annular branch pipes are connected to the ozone main pipe; each oxidation zone corresponds to an ozone annular branch pipe, and the ozone annular branch pipe is connected to the ozone spray gun of the corresponding oxidation zone.

[0011] Furthermore, the air inlet of the ozone spray gun is threadedly connected to the ozone annular branch pipe, and a hose is arranged in the middle of the connection. The ozone spray gun passes through the shell and is tilted toward the reactor outlet, and the air outlet of the ozone spray gun forms an angle of 75 degrees with the central axis of the reactor shell.

[0012] The oxidation partitions in the shell are set up, preferably 2-3, through which NOx The oxidation creates multiple reaction spaces. Different ozone dosages are added in different areas. The ozone ratio can be adjusted according to the concentration of each pollutant in the flue gas, reducing unnecessary consumption, eliminating excessive ozone escape, and increasing NO x In order to improve the overall oxidation reaction degree, the flue gas and ozone are mixed in each oxidation zone and flow to the reactor outlet. The ozone main pipe, annular branch pipe and ozone spray gun cooperate with each other. Through the optimization of the spray gun position, ozone and flue gas can be spirally mixed and enter the turbulence device to ensure further uniform mixing, shortening the reaction time and space.

[0013] Furthermore, the spoiler device includes a grille plate and a spoiler guide plate, and the spoiler device causes the flue gas and ozone to mix and generate turbulence, thereby ensuring that the ozone and NO in the flue gas are x Furthermore, the spoiler guides are arranged in the holes of the grille plate at intervals, and the mixing of ozone and flue gas is strengthened under the action of the spoiler guides, shortening the reaction stroke and improving the oxidation of NO by ozone. x efficiency.

[0014] Furthermore, the spoiler guide plate is welded to the grid plate, and the grid plate is welded to the inner wall of the shell. The design of the grid plate can make the total pressure loss in the reactor shell not exceed 1000Pa.

[0015] The working principle of the utility model is as follows:

[0016] The flue gas enters from the reactor inlet, and the ozone prepared by the ozone generator enters the ozone main pipe after dilution, and then is sent to the ozone nozzles of the two oxidation zones through the annular branch pipe. The ozone is evenly sprayed into the 1# oxidation zone and the 2# oxidation zone in the oxidation reactor, mixed with the flue gas in a spiral shape, and then enters the turbulence device to mix the flue gas and ozone to produce turbulence to ensure that the ozone and NO in the flue gas are x The ozone and NO in the flue gas can fully contact and react x After sufficient contact and reaction, they enter the flue from the reactor outlet.

[0017] The beneficial effects of the utility model are as follows:

[0018] (1) The utility model proposes to divide the main body of the ozone denitrification reactor into two or more oxidation zones to form NO x The oxidation creates multiple reaction spaces, and the ozone dosage in different areas is different. The ozone ratio can be adjusted according to the concentration of each pollutant in the flue gas to reduce unnecessary consumption. While ensuring a certain denitrification efficiency, it can save costs and eliminate excessive ozone escape, thereby increasing NO x The overall degree of oxidation reaction.

[0019] (2) The ozone denitrification reactor of the utility model is composed of an ozone spray gun, a flow disturbance device, a ring branch pipe, etc., to achieve uniform distribution of ozone flow and speed in the same oxidation zone. Under the action of the flow disturbance guide plate, the mixing of ozone and flue gas is strengthened, the reaction stroke is shortened, and the ozone oxidation of NO is improved. x efficiency.

[0020] (3) The ozone distributor for zoned oxidation described in the utility model is simple in design, highly adjustable, and has obvious engineering advantages. Combined with the actual site conditions, the design structure is diverse, and the ozone spray gun is easy to install, clean, and repair. It is suitable for wide application in oxidation-absorption denitrification technology. The reactor has a low cost investment and can also be transformed using the original flue gas pipeline. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is the front view of the utility model.

[0022] Figure 2 It is a left view of the utility model.

[0023] Figure numerals: 1-reactor inlet, 2-reactor outlet, 3-1# oxidation partition, 4-2# oxidation partition, 5-ozone spray gun, 6-turbulator, 7-shell, 8-grid plate, 9-turbulator guide plate, 10-ozone main pipe, 11-ozone annular branch pipe. DETAILED DESCRIPTION

[0024] Example 1

[0025] like Figure 1 As shown, a partitioned ozone denitrification reactor comprises a shell 7, a reactor inlet 1, a reactor outlet 2, a turbulent device 1, a turbulent device 2, an ozone main pipe 10, an ozone annular branch pipe 1, and an ozone annular branch pipe 2. The shell 7 is arranged horizontally, the reactor inlet 1 is arranged on one side of the shell 7, and the reactor outlet 2 is arranged on the other side of the shell 7. A 1# oxidation partition 3 and a 2# oxidation partition 4 are arranged in the shell 7. The optimal oxidation partition is set to 2-3. By dividing the reactor body into 2-3 oxidation partitions, NO x The oxidation creates multiple reaction spaces. Different ozone dosages are added in different areas. The ozone ratio can be adjusted according to the concentration of each pollutant in the flue gas, reducing unnecessary consumption, eliminating excessive ozone escape, and increasing NO xIn order to improve the overall oxidation reaction degree, after the flue gas and ozone are mixed in the 1# oxidation partition 3 and the 2# oxidation partition 4, a turbulent device 1 and a turbulent device 2 are arranged in the direction of the reactor outlet 2, and the turbulent device 1 is close to the 1# oxidation partition 3, and the turbulent device 2 is close to the 2# oxidation partition 4. The ozone main pipe 10 is arranged above the shell 7 and close to the reactor inlet 1, and is connected to the ozone annular branch pipe 1 and the ozone annular branch pipe 2 surrounding the shell 7. The ozone can be evenly distributed through the ozone main pipe 10, the ozone annular branch pipe 1 and the ozone annular branch pipe 2. Ozone spray guns 5 are evenly arranged on the ozone annular branch pipe 1 and the ozone annular branch pipe 2. The ozone spray gun 5, the turbulent device 1, the turbulent device 2, the ozone annular branch pipe 1, the ozone annular branch pipe 2 and the like are composed to achieve uniform distribution of ozone flow and speed of the spray gun in the same oxidation zone. The turbulent device causes the flue gas and ozone to mix and generate turbulence, thereby ensuring that ozone and NO in the flue gas are separated. x Able to fully contact and react.

[0026] Example 2

[0027] Based on the structure of Example 1, Figure 2 As shown, the spoiler device 6 includes a grid plate 8 and a spoiler guide plate 9. The grid plate 8 is welded to the reactor shell 7. The grid plate 8 is designed so that the total pressure loss in the reactor does not exceed 1000Pa. The grid plate 8 can effectively filter solid particles and suspended matter in the flue gas. The spoiler baffles 9 are welded to the grid plate 8. The spoiler baffles 9 are arranged at intervals in the holes of the grid plate 8. After the flue gas and ozone are mixed in the 1# oxidation partition 3 and the 2# oxidation partition, they flow into the spoiler device 6. The mixing of ozone and flue gas is enhanced under the action of the spoiler guide plate. The spoiler device 6 causes the flue gas and ozone to mix and produce turbulence, ensuring that the ozone and NOx in the flue gas can fully contact and react.

[0028] Example 3

[0029] Based on the structure of Example 1 or 2, Figure 1-2 As shown, the ozone annular branch pipe 11 is evenly provided with four ozone spray guns 5. By evenly arranging the ozone spray guns on the ozone annular branch pipe, the flue gas and ozone can be mixed in all directions in the oxidation reaction zone.

[0030] Furthermore, the ozone spray gun 5 forms an angle of 75 degrees with the shell 7, the head of the ozone spray gun 5 is inserted into the flue and connected to the flue through a thread, the air inlet end of the ozone spray gun 5 is also connected to the ozone annular branch pipe 11 through a thread, and a hose is connected in the middle for easy disassembly and assembly, and a plurality of small holes are arranged on the head of the ozone spray gun for injection. By optimizing the position of the ozone spray gun 5, ozone and flue gas can be spirally mixed and enter the turbulence device 6 to ensure further uniform mixing, thereby shortening the reaction time and space.

Claims

1. A partitioned ozone denitrification reactor, characterized in that: The invention comprises a shell (7) arranged transversely and a reactor inlet (1) and a reactor outlet (2) located on both sides of the shell (7); the shell (7) is cylindrical; at least two oxidation partitions are arranged inside the shell (7); a plurality of ozone spray guns (5) are evenly arranged radially on the shell (7) corresponding to each oxidation partition; the ozone spray guns (5) pass through the shell (7) and are arranged obliquely toward the reactor outlet (2); the gas outlet end of the ozone spray gun (5) forms an angle of 75 degrees with the central axis of the reactor shell; an ozone main pipe is arranged outside the shell (7) (10) and a plurality of ozone annular branch pipes (11), all of which are connected to the ozone main pipe (10); each oxidation zone corresponds to an ozone annular branch pipe (11), and the ozone annular branch pipe (11) is connected to the ozone spray gun (5) of the corresponding oxidation zone, and a flow disturbance device (6) for mixing flue gas and ozone to generate turbulence is arranged between each two oxidation zones, and the flow disturbance device (6) comprises a grid plate (8) and a flow disturbance guide plate (9), and the flow disturbance guide plate (9) is arranged in the holes of the grid plate (8) at intervals.

2. A zoned ozone denitrification reactor according to claim 1, characterized in that: The air inlet end of the ozone spray gun (5) is threadedly connected to the ozone annular branch pipe (11), and a hose is arranged in the middle of the connection.

3. A zoned ozone denitrification reactor according to claim 2, characterized in that: The spoiler guide plate (9) is welded to the grille plate (8).

4. A zoned ozone denitrification reactor according to claim 2 or 3, characterized in that: The grid plate (8) is welded to the inner wall of the shell (7).

5. A zoned ozone denitrification reactor according to claim 4, characterized in that: The total pressure loss in the shell (7) is ≤1000 Pa.

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