CN112058053A

CN112058053A - Flue gas wet denitration device and method

Info

Publication number: CN112058053A
Application number: CN202010783874.4A
Authority: CN
Inventors: 孙经纬; 刘飞
Original assignee: Nanjing Halls Biological Technology Co Ltd
Current assignee: Nanjing Halls Biological Technology Co Ltd
Priority date: 2020-08-06
Filing date: 2020-08-06
Publication date: 2020-12-11
Also published as: WO2022027967A1

Abstract

The invention discloses a flue gas wet denitration device and a method, which comprises a box body for bearing ammonia water and a driving motor, wherein supporting legs are symmetrically arranged at two sides of the lower end of the box body, supporting blocks are arranged at the lower ends of the supporting legs, a discharge pipe for discharging is arranged at the lower left side of the box body, a discharge valve is arranged on the discharge pipe, a stirring pipe is arranged at the output end of the driving motor, and a mixing box which is convenient for the penetration of the stirring pipe is arranged at the top in the box body. Thereby increasing the concentration of ozone and flue gas and being beneficial to improving the reaction speed.

Description

Flue gas wet denitration device and method

Technical Field

The invention relates to the technical field of flue gas treatment equipment, in particular to a wet flue gas denitration device and a wet flue gas denitration method.

Background

Currently, the commonly used flue gas denitration methods are a Selective Catalytic Reduction (SCR) method and a non-selective catalytic reduction (SNCR) method. The SCR method has high denitration efficiency, but the initial investment is large, ammonia escape is easy to generate, the environment is polluted, part of SO2 is oxidized to form SO3 under the action of a catalyst in an SCR reactor, and the SO3 reacts with ammonia gas which does not participate in the denitration reaction to generate ammonium bisulfate, SO that the catalyst and an air preheater are damaged. The SNCR denitration technology uses a hearth as a reactor, has simple system and low investment and operation and maintenance cost, but has lower denitration efficiency and can not meet the requirement of ultralow emission. Traditional wet denitration adopts alkali lye to absorb NOx, generates a large amount of sodium nitrate and sodium nitrite, causes secondary pollution easily, and denitration efficiency is lower.

In order to solve the problems, the prior patent with the patent publication number of CN208482234U discloses a denitration device, nitrogen oxides in flue gas are removed by adopting methods of ozone oxidation and ammonia water absorption, the denitration efficiency is over 85 percent, compared with other desulfurization and denitration devices, ozone is arranged in an inlet flue and is sprayed, the flow area of the flue gas is small at the moment, the contact is sufficient, the oxidation efficiency is ensured, a process water system is increased, the trapping efficiency of NO2 is ensured, and the subsequent reaction is favorably carried out;

however, the technical scheme described in the prior patent is only simple to mix ozone and flue gas simply, and can not ensure that nitric oxide in the flue gas is oxidized, and in addition, the device can lead to the accumulation of internal solid impurities during actual operation, and then lead to the problem that the later stage can not work, and based on this, the flue gas wet denitration device and the method are provided.

Disclosure of Invention

The invention aims to provide a flue gas wet denitration device and a flue gas wet denitration method, which aim to solve the problems in the background art.

In order to achieve the purpose, the invention provides the following technical scheme:

a wet flue gas denitration device comprises a box body and a driving motor, wherein the box body is used for bearing ammonia water, supporting legs are symmetrically arranged on two sides of the lower end of the box body, supporting blocks are arranged at the lower ends of the supporting legs, a discharging pipe used for discharging materials is arranged on the lower left side of the box body, a discharging valve is arranged on the discharging pipe, a stirring pipe is arranged at the output end of the driving motor, a mixing box convenient for the penetration of the stirring pipe is arranged at the top in the box body, an air inlet is formed in the surface of the stirring pipe where the mixing box is located, a sealing bearing matched with the stirring pipe is arranged on the mixing box, a flue gas inlet pipe on the right side of the box body is communicated with the mixing box, an air inlet port on the left side of the box body is connected with an ozone generator through a guide pipe;

the outer side of the stirring pipe is coaxially provided with a rotary cylinder, and the length of the rotary cylinder is greater than that of the stirring pipe, so that the lower port of the stirring pipe is positioned in the rotary cylinder, and a compressed air column is constructed in the rotary cylinder by utilizing atmospheric pressure;

a plurality of stirring plates are distributed on the outer side of the lower end of the rotary drum in an array mode, and the stirring plates rotate along with the rotary drum, so that gas can be further mixed with ammonia water, and nitrogen dioxide in the gas can be absorbed.

The utility model discloses a box, including a rotatory section of thick bamboo, the rotatory section of thick bamboo outside is equipped with promotes a section of thick bamboo, promote a section of thick bamboo inside rotatory section of thick bamboo surface is equipped with the promotion blade, it has at least one back flow to promote a section of thick bamboo upper end outside array distribution, when promoting a section of thick bamboo rotatory along with the rotatory section of thick bamboo, the promotion blade can upwards promote the aqueous ammonia along promoting a section of thick bamboo inner wall with the aqueous ammonia, and the aqueous ammonia falls to inside the box from the back flow.

As a further scheme of the invention: the filtering component comprises a screening ring plate which is arranged on the inner wall of the box body in an annular mode, and a plurality of filtering nets are embedded in the screening ring plate;

promote a section of thick bamboo outside and be equipped with the side lever that is located screening crown plate top, the side lever downside is equipped with the cleaning brush that is used for supporting the filter screen surface, the side lever is certain contained angle setting with promotion section of thick bamboo surface tangent line.

As a further scheme of the invention: the included angle is sixty degrees.

As a further scheme of the invention: the surface of the box body where the screening ring plate is located is provided with an opening and a box door arranged at the opening.

As a further scheme of the invention: the lower end of the rotary cylinder is provided with a guide cone, and the diameter of the bottom of the guide cone is larger than that of the lifting cylinder.

As a further scheme of the invention: the feed inlet at the top of the box body is also connected with a storage box for storing hydrogen peroxide.

As a further scheme of the invention: and a detector for detecting the concentrations of nitrate ions, ammonium ions and hydrogen peroxide is arranged in the box body.

A treatment method of a flue gas wet denitration device is characterized in that an ammonia solution is filled in a box body, then flue gas and ozone are sent into a mixing box to be primarily mixed, the reducibility in the flue gas is oxidized, then the mixed gas forms an air column in a rotary cylinder, so that the air in the rotary cylinder is compressed, the overflowed mixed gas can be stirred by a stirring plate, then the mixed gas rises and is discharged from an exhaust pipe, when a lifting cylinder rotates along with the rotary cylinder, a lifting blade can push the ammonia water upwards along the inner wall of the lifting cylinder, then the ammonia water falls back into the box body from a return pipe, the inner wall of the box body is provided with a filter assembly for receiving the ammonia water falling from the return pipe and purifying the ammonia water, so that the ammonia water absorbing nitrogen dioxide can be continuously sent into the filter assembly to be filtered, thereby avoiding the accumulation of impurities in the device, and a cleaning solution spraying the gas can be, thereby purifying the floating gas again.

Compared with the prior art, the invention has the beneficial effects that: the invention improves the defects of the existing device, so that ozone and flue gas can be fully mixed, the oxidation effect is improved, an air column is constructed in the box body, the mixed gas of the ozone and the flue gas is compressed by utilizing the atmospheric pressure, a buffer area is provided for the flue gas and the ozone, the reductive substance in the flue gas can be fully oxidized conveniently, in addition, the air column is compressed under the action of the atmospheric pressure, the concentration of the ozone and the flue gas is increased, the reaction speed is improved, in addition, hydrogen peroxide is added as a liquid oxidant, the reductive substance in the flue gas is further oxidized by the liquid oxidant, and the gas generated by decomposing the hydrogen peroxide can further promote the mixing effect of the oxygen, the ozone and the reductive gas, so that the reductive gas can react more fully.

Drawings

FIG. 1 is a schematic structural diagram of the present invention.

Fig. 2 is a schematic structural view of a lift cylinder and a rotary cylinder according to the present invention.

FIG. 3 is a schematic view of the structure of the side bar and the lifting cylinder of the present invention.

Wherein: the device comprises a flue gas inlet pipe 1, a booster pump 2, a mixing box 3, an air inlet 4, a lifting cylinder 5, a box body 6, a stirring pipe 7, a rotating cylinder 8, lifting blades 9, supporting legs 10, supporting blocks 11, a discharging pipe 12, a guide cone 13, a stirring plate 14, a filtering net 15, a screening ring plate 16, a cleaning brush 17, a side lever 18, a return pipe 19, a mixing blade 20, an exhaust pipe 21, an ozone generator 22 and a driving motor 23.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

Referring to fig. 1-3, in the embodiment of the present invention, a wet flue gas denitration device includes a box 6 for bearing ammonia water and a driving motor 23, wherein two sides of the lower end of the box 6 are symmetrically provided with support legs 10, the lower end of each support leg 10 is provided with a support block 11, the left lower side of the box 6 is provided with a discharge pipe 12 for discharging materials, the discharge pipe 12 is provided with a discharge valve, the output end of the driving motor 23 is provided with a stirring pipe 7, the top inside the box 6 is provided with a mixing box 3 through which the stirring pipe 7 can conveniently penetrate, the surface of the stirring pipe 7 where the mixing box 3 is located is provided with an air inlet 4, the mixing box 3 is provided with a seal bearing matched with the stirring pipe 7, a flue gas inlet pipe 1 on the right side of the box 6 is communicated with the mixing box 3, an air inlet port on the left side of the box 6 is connected with an ozone generator 22 through a conduit, the surface of the stirring pipe 7 where the mixing box 3 is located is provided with the mixing blades 20, and under the driving of the driving motor 23, the mixing blades 20 can rotate along with the stirring pipe 7, so that the flue gas and the ozone are rapidly mixed, nitrogen monoxide in the flue gas is oxidized into nitrogen dioxide, the ozone and the flue gas can be fully mixed by means of the rotating force of the stirring pipe, and the defect of insufficient mixing in the existing device is overcome;

the rotary cylinder 8 is coaxially arranged on the outer side of the stirring pipe 7, the length of the rotary cylinder 8 is greater than that of the stirring pipe 7, so that the lower port of the stirring pipe 7 is positioned in the rotary cylinder 8, the arrangement has the advantage that an air column is formed in the rotary cylinder 8, a buffer area is provided for the flue gas and ozone, the reduction substances in the flue gas can be fully oxidized, and in addition, the air column is compressed under the action of atmospheric pressure, so that the concentration of the ozone and the flue gas is increased, and the reaction speed is improved;

a plurality of stirring plates 14 are distributed on the outer side of the lower end of the rotating cylinder 8 in an array mode, and the stirring plates 14 rotate along with the rotating cylinder 8, so that gas can be further mixed with ammonia water, and nitrogen dioxide in the gas can be absorbed.

8 outsides of rotary drum are equipped with lifting

cylinder

5, 8 surfaces of the inside rotary drum of lifting cylinder 5 are equipped with

promotion blade

9, 5 upper end outside array distribution of lifting cylinder have at least one back flow 19, when lifting cylinder 5 is rotatory along with rotary drum 8, promote blade 9 and can upwards promote the aqueous ammonia along lifting cylinder 5 inner wall, the aqueous ammonia falls back to inside box 6 from back flow 19 afterwards, 6 inner walls of box are equipped with and are used for accepting back flow 19 whereabouts aqueous ammonia and carry out purification treatment's filter assembly to it, just so can be continuous send into filter assembly with the aqueous ammonia that absorbs nitrogen dioxide and filter, thereby avoid the inside impurity of device to pile up, and here can produce the washing liquid that sprays gas after filtering, thereby carry out purification treatment once more to the gas of come-up.

Filter component is the screening crown plate 16 of cyclic annular setting including setting up at 6 inner walls of box, inlay on the screening crown plate 16 and be equipped with a plurality of filter screen 15, impurity in the ammonia can pile up on screening crown plate 16 like this, avoids impurity to pile up in 6 bottoms of box and causes the problem of jam, 6 surfaces of box at the position of screening crown plate 16 are equipped with the opening and set up the chamber door at the opening part, and the impurity that the later stage can be on with screening crown plate 16 through opening the chamber door takes out.

In order to avoid impurity to pile up on filter screen 15 surface, promote a section of thick bamboo 5 outside and be equipped with the side lever 18 that is located the 16 tops of screening crown plate, 18 downside of side lever are equipped with the clearance brush 17 that is used for supporting the 15 surfaces of filter screen, side lever 18 is certain contained angle setting with 5 surperficial tangents of a promotion section of thick bamboo, the contained angle is sixty degrees, and this kind of mode that is certain contained angle setting can make the impurity of being cleared up to displacement all around, just so avoids impurity to block up the filter screen, has also made things convenient for the maintenance in maintainer later stage simultaneously.

Example 2

In order to prevent ozone overflowing from the bottom of the rotary cylinder 8 from entering the interior of the lifting cylinder 5, the lower end of the rotary cylinder 8 is provided with a guide cone 13, the diameter of the bottom of the guide cone 13 is larger than that of the lifting cylinder 5, and thus gas overflowing along the edge of the lower end of the guide cone 13 cannot be captured by the lifting cylinder 3.

Example 3

The feed inlet at 6 tops of box still is connected with the storage box that is used for saving hydrogen peroxide, can be through adding hydrogen peroxide in aqueous ammonia inside, through liquid oxidant further oxidation to reducing substance in the flue gas, and utilize hydrogen peroxide decomposition to produce gaseous mixed effect that can further make oxygen, ozone and reducing gas for reducing gas reaction is more abundant.

Example 4

The inside detector that is equipped with detection ion concentration of box 6 through the detection to nitrate ion, ammonium ion, hydrogen peroxide solution concentration to control 6 inside material concentrations of box, so that in time change the material, guarantee that the device lasts effectual purification performance.

The working principle of the invention is as follows: ammonia water solution is filled in the box body 6, then the flue gas and the ozone are sent into the mixing box to be primarily mixed, so that the reducibility in the flue gas is oxidized, then the mixed gas forms an air column in the rotary drum 8, the air in the rotary drum is compressed, a buffer area is provided for the flue gas and the ozone, the reducibility substances in the flue gas can be fully oxidized, and in addition, the air column is compressed under the action of atmospheric pressure, so that the concentration of the ozone and the flue gas is increased, and the reaction speed is favorably improved;

the gas mixture that overflows can be stirred by stirring board 14, then rises and then discharges from blast pipe 21, when lifting cylinder 5 is rotatory along with rotary drum 8, it can upwards promote the aqueous ammonia along lifting cylinder 5 inner wall to promote blade 9, and the aqueous ammonia falls to inside box 6 from back flow 19 back afterwards, 6 inner walls of box are equipped with and are used for accepting 19 whereabouts aqueous ammonia of back flow and carry out purification treatment's filter assembly to it, and the aqueous ammonia that just so can be continuous will absorb nitrogen dioxide sends into filter assembly and filters, thereby avoids the inside impurity of device to pile up, and here can produce the washing liquid that sprays gas after filtering, thereby carry out purification treatment once more to the gas of come-up.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.

Claims

1. A wet flue gas denitration device comprises a box body (6) and a driving motor (23), wherein the box body (6) is used for bearing ammonia water, supporting legs (10) are symmetrically arranged on two sides of the lower end of the box body (6), supporting blocks (11) are arranged at the lower ends of the supporting legs (10), a discharging pipe (12) for discharging is arranged on the lower left side of the box body (1), a discharging valve is arranged on the discharging pipe (12), and a stirring pipe (7) is arranged at the output end of the driving motor (23);

the device is characterized in that a mixing box (3) convenient for a mixing pipe (7) to penetrate through is arranged at the top in a box body (1), an air inlet (4) is arranged on the surface of the mixing pipe (7) where the mixing box (3) is located, a sealing bearing matched with the mixing pipe (7) is arranged on the mixing box (3), a flue gas inlet pipe (1) on the right side of the box body (1) is communicated with the mixing box (3), an air inlet port on the left side of the box body (1) is connected with an ozone generator (22) through a guide pipe, booster pumps (2) used for promoting gas circulation are arranged on the flue gas inlet pipe (1) and the exhaust end of the ozone generator (22), and mixing blades (20) are arranged on the surface of the mixing pipe (7) where the mixing box (3);

a rotating cylinder (8) is coaxially arranged on the outer side of the stirring pipe (7), the length of the rotating cylinder (8) is greater than that of the stirring pipe (7), so that the lower port of the stirring pipe (7) is positioned in the rotating cylinder (8), and a compressed air column is constructed in the rotating cylinder (8) by utilizing atmospheric pressure;

a plurality of stirring plates (14) are distributed on the outer side of the lower end of the rotary cylinder (8) in an array manner;

rotatory section of thick bamboo (8) outside is equipped with lifting cylinder (5), lifting cylinder (5) inside rotatory section of thick bamboo (8) surface is equipped with and promotes blade (9), lifting cylinder (5) upper end outside array distribution has at least one back flow (19), when lifting cylinder (5) is rotatory along with rotatory section of thick bamboo (8), promotes blade (9) and can upwards promote the aqueous ammonia along lifting cylinder (5) inner wall, and the aqueous ammonia falls to inside box (6) from back flow (19) back afterwards, box (6) inner wall is equipped with and is used for accepting back flow (19) whereabouts aqueous ammonia and carries out purification treatment's filter assembly to it.

2. The wet flue gas denitration device according to claim 1, wherein the filtering assembly comprises a screening ring plate (16) which is annularly arranged on the inner wall of the box body (6), and a plurality of filter screens (15) are embedded on the screening ring plate (16);

promote a section of thick bamboo (5) outside and be equipped with side lever (18) that are located screening crown plate (16) top, side lever (18) downside is equipped with and is used for supporting clearance brush (17) on filter screen (15) surface, side lever (18) are certain contained angle setting with a promotion section of thick bamboo (5) surface tangent line.

3. The wet flue gas denitration device of claim 2, wherein the included angle is sixty degrees.

4. The wet flue gas denitration device of claim 2, wherein an opening and a box door arranged at the opening are arranged on the surface of the box body (6) where the screening ring plate (16) is arranged.

5. The wet flue gas denitration device according to claim 1, wherein a guide cone (13) is arranged at the lower end of the rotary drum (8), and the diameter of the bottom of the guide cone (13) is larger than that of the lifting drum (5).

6. The wet flue gas denitration device according to any one of claims 1 to 5, wherein a feed inlet at the top of the box body (6) is further connected with a storage tank for storing hydrogen peroxide.

7. The wet flue gas denitration device according to claim 1, wherein a detector for detecting the concentrations of nitrate ions, ammonium ions and hydrogen peroxide is arranged in the box body (6).

8. A treatment method of a flue gas wet denitration device according to any one of claims 1 to 7, wherein an ammonia solution is filled in a box body (6), then the flue gas and ozone are sent into a mixing box to be primarily mixed, so that the reducibility in the flue gas is oxidized, then the mixed gas forms an air column in a rotary drum (8), so that the air in the rotary drum is compressed, the overflowed mixed gas can be stirred by a stirring plate (14), then rises and is discharged from an exhaust pipe (21), when a lifting drum (5) rotates along with the rotary drum (8), ammonia water is pushed upwards along the inner wall of the lifting drum (5) by a lifting blade (9), then the ammonia water falls back into the box body (6) from a return pipe (19), and a filtering component for receiving the ammonia water falling from the return pipe (19) and purifying the ammonia water is arranged on the inner wall of the box body (6), so can be continuous send into the aqueous ammonia that absorbs nitrogen dioxide and filter assembly and filter to avoid the inside impurity of device to pile up, and here can produce the washing liquid that sprays gas after filtering, thereby carry out purification treatment once more to the gas of come-up.