CN210993762U

CN210993762U - Tail gas treatment equipment

Info

Publication number: CN210993762U
Application number: CN201921385750.XU
Authority: CN
Inventors: 唐子杰; 谢奇旭; 谭发祥
Original assignee: Suzhou Topco Construction Ltd
Current assignee: Suzhou Topco Construction Ltd
Priority date: 2019-08-23
Filing date: 2019-08-23
Publication date: 2020-07-14
Anticipated expiration: 2029-08-23

Abstract

A tail gas treatment device receives and treats tail gas. The tail gas treatment equipment comprises a demisting device and an iron-based catalyst reaction device. The demisting device adsorbs and treats water vapor in the tail gas and outputs dehydrated tail gas. The iron-based catalyst reaction device is connected with the demisting device and receives the dehydrated tail gas. The iron-based catalyst reaction device comprises an iron-based catalyst for catalytically reducing the oxidizing gas in the dehydrated tail gas to generate exhaust gas and then discharging the exhaust gas. Here, the iron-based catalytic reactor suitably used in the liquid phase can continuously perform catalytic reaction of the catalyst under the condition that the dehydrated exhaust gas still contains moisture, thereby sufficiently removing the oxidizing gas in the treated exhaust gas and preventing the discharged exhaust gas from containing components harmful to the human body.

Description

Tail gas treatment equipment

Technical Field

The utility model relates to an exhaust-gas treatment field especially relates to a tail gas treatment equipment.

Background

In the conventional treatment of waste water and waste gas, residual gas is usually oxidized to remove harmful free radicals and Volatile Organic Compounds (VOC). The removal method is generally to oxidize and reduce the exhaust gas into nitrogen, water vapor and carbon dioxide before discharging the exhaust gas into the atmosphere. In the latter stage of the exhaust gas treatment, generally referred to as tail gas, there are usually small amounts of incompletely reacted reactants, which are then burned and plasma treated to completely remove substances harmful to the human body.

In the liquid phase oxidation reaction, an oxidizing gas, for example, ozone (O), may be added₃) However, their solubility in aqueous solutions is rather low and they easily escape into the air when they are passed in, partly without reacting with the pollutants in the liquid phase, so that the off-gas, in addition to the volatile reactants in the liquid phase, may also be present in the oxidizing gases added during the oxidation reaction, the residues of these oxidizing gases also being harmful to humans and generally having a defined emission standard (ozone being the volatile reactant in the liquid phase)<0.1ppm)。

Therefore, the treatment of the tail gas requires further reduction of these oxidants. In the prior art, catalytic reduction of ozone can be performed by manganese-based catalysts, but the manganese-based catalysts are susceptible to moisture, and a poisoning phenomenon occurs in which the efficiency of the catalysts is reduced, which may reduce the reduction efficiency and cause the emission to be substandard.

SUMMERY OF THE UTILITY MODEL

In order to solve the foregoing problem, herein, a tail gas treatment device is provided, which receives and treats tail gas. The tail gas treatment equipment comprises a demisting device and an iron-based catalyst reaction device. The demisting device adsorbs and treats water vapor in the tail gas and outputs dehydrated tail gas. The iron-based catalyst reaction device is connected with the demisting device and used for receiving the dehydrated tail gas, and the iron-based catalyst reaction device comprises an iron-based catalyst and is used for catalytically reducing the oxidizing gas in the dehydrated tail gas to generate exhaust gas and then discharging the exhaust gas.

In some embodiments, the tail gas treatment facility further comprises a heating device. The heating device is arranged between the demisting device and the iron-based catalyst reaction device, receives the dehydrated tail gas and heats the dehydrated tail gas.

Still further, in some embodiments, the tail gas treatment facility further comprises a heat exchanger. The heat exchanger comprises a first gas flow channel and a second gas flow channel, one end of the first gas flow channel is connected with the demisting device so as to input the dehydrated tail gas, and the other end of the first gas flow channel is connected with the heating device. One end of the second gas flow channel is connected with the iron-based catalyst reaction device so as to input exhaust gas, and the exhaust gas and the dehydrated tail gas exchange heat in the heat exchanger.

In some embodiments, the moisture content of the dehydrated tail gas is from 0.5 to 15 wt%.

Further, in some embodiments, the gas emission treatment device is a scrubber or an adsorption device.

Further, in some embodiments, the gas discharge processing apparatus is a plasma processing apparatus.

In some embodiments, the iron-based catalyst in the iron-based catalytic reactor is in a solid state.

In some embodiments, the oxidizing gas is ozone.

In some embodiments, the tail gas treatment facility further comprises a carbon capture device. The carbon capture device receives the exhaust gas, performs carbon fixation reaction and then discharges the exhaust gas.

As described in the foregoing embodiment, the exhaust gas treatment apparatus can continuously perform catalytic reaction of the catalyst under the condition that the dehydrated exhaust gas still contains moisture by using the iron-based catalyst reaction device suitably applied to the liquid phase, so as to remove the oxidizing gas in the treated exhaust gas, thereby preventing the discharged exhaust gas from containing components harmful to human body.

Drawings

FIG. 1 is a block diagram of the units of an off-gas treatment plant.

Wherein, the reference numbers:

1 Tail gas treatment equipment

10 defogging device

20 iron-based catalyst reaction device

30 heating device

40 Heat exchanger

41 first gas flow path

43 second gas flow path

50 gas emission treatment device

60 carbon capture device

G exhaust gas

G_WTreating tail gas

G_LDehydrated tail gas

Detailed Description

It will be understood that when an element such as "is connected to" another element, it can mean that the element is directly on the other element or that there may be intermediate elements connecting the element to the other element. In contrast, when an element is referred to as being "directly on" or "directly connected to" another element, it is understood that there are no intervening elements explicitly defined herein.

It will be understood that, although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, or sections, these elements, components, regions, and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, or section from another element, component, region, layer, or section. Thus, a discussion of "a first element," "a first component," "a first region," or "a first portion" below may be interpreted as "a second element," "a second component," "a second region," or "a second portion" without departing from the teachings herein.

FIG. 1 is a block diagram of the units of an off-gas treatment plant. As shown in FIG. 1, the tail gas treatment facility 1 receives treated tail gas G from a wastewater or waste gas treatment facility (not shown) after reaction_W. Treatment of tail gas G_WContaining residual oxidizing gas, e.g. ozone (O)₃) And the like. Treatment of tail gas G_WMay also contain incompletely reacted Volatile Organic Compounds (VOC), nitrogen oxygen gas (NO, NO)₂) And the like. However, this is merely exemplary and not limiting, oxidativeThe gas may also be chlorine (Cl)₂) And the like.

The tail gas treatment equipment 1 comprises a demisting device 10 and an iron-based catalytic reaction device 20. Demisting device 10 for adsorbing and treating tail gas G_WMiddle water vapor and output dehydrated tail gas G_L. In general, the dehydrated tail gas G_LStill containing 0.5 to 15 wt% moisture.

The iron-based catalyst reaction device 20 receives the dehydrated tail gas G_LThe iron-based catalytic reactor 20 contains at least an iron-based catalyst, such as iron hydroxide (FeOOH). The iron-based catalyst is solid and has small gaps, so that the dehydrated tail gas G can be obtained_LThe oxidizing gas in (2) is subjected to a catalytic reduction reaction in the iron-based catalytic reactor 20, for example, the following chemical reaction formula (1), and the exhaust gas G is generated and discharged. However, equation (1) is merely exemplary and not intended to be limiting.

Chemical reaction formula (1): 2O₃(g)→3O₂(g)。

Since the iron-based catalyst is suitable for the catalytic reaction in the liquid phase, even if the exhaust gas G is dehydrated_LThe catalyst is not poisoned due to the moisture, so that the reaction rate is reduced.

Referring again to fig. 1, in some embodiments, the tail gas treatment device 1 further comprises a heating device 30. A heating device 30 disposed between the demister 10 and the iron-based catalytic reactor 20 for receiving the dehydrated tail gas G_LAnd for dehydration tail gas G_LAnd (4) heating. Here, the heating device 30 discharges the dehydrated tail gas G_LHeating to 40 to 150 ℃ can improve the reaction efficiency of the iron-based catalytic reactor 20 for the reduction of the oxidizing gas, in addition to further removing water.

Referring again to fig. 1, in other embodiments, the tail gas treatment device 1 may further comprise a heat exchanger 40. The heat exchanger 40 includes a first gas flow path 41 and a second gas flow path 43. One end of the first gas flow passage 41 is connected with the demisting device 10 for inputting the dehydrated tail gas G_LAnd the other end is connected to a heating device 30. One end of the second gas channel 43 is connected to the Fe-based catalytic reaction device 20 for inputting the exhaust gas G, and the other end is connected to the exhaust pipeline for exhausting the exhaust gas G and the catalystWater tail gas G_LHeat exchange is performed in the heat exchanger 40. Thus, the energy used for heating the heating device 30 can be further reduced, so as to achieve the effect of energy saving.

As shown in fig. 1, in some embodiments, the tail gas treatment device 1 further includes a gas emission treatment device 50, and the gas emission treatment device 50 is connected to the iron-based catalytic reaction device 20, and further purifies and discharges the exhaust gas G. The gas emission treatment device 50 includes various devices capable of purifying the exhaust gas G, for example, reducing fine dust and harmful substances, which will be described below by way of example, but the following embodiments are only examples and are not intended to be limiting.

In some embodiments, the gas discharge processing device 50 may be a washing tower or an adsorption device, and the fine solid particles of the exhaust gas G may be reduced by washing and settling the exhaust gas G through the washing tower or adsorbing the exhaust gas G through the adsorption device.

In other embodiments, to further reduce the residual Volatile Organic Compounds (VOC), nitrogen oxides (NO, NO) in the exhaust gas G₂) In this case, the gas discharge processing device 50 may be a plasma processing device, which further cracks and oxidizes the gas molecules by plasma to become water vapor, carbon dioxide or nitrogen, which is less harmful to human body.

Referring again to fig. 1, in some embodiments, the tail gas treatment facility 1 further comprises a carbon capture device 60. The carbon capture device 60 receives the exhaust gas G and performs a carbon sequestration reaction. For example, in the chemical reaction formula (2) below, the carbon dioxide in the exhaust gas G is subjected to a carbon fixation reaction, and then the exhaust gas G can be discharged. However, the chemical reaction formula (2) is merely an example, and is not intended to be limiting.

Chemical reaction formula (2): CO 2₂(g)+CaO(s)→CaCO₃(s)。

The purpose of the carbon capture device 60 to receive the exhaust gas G is to reduce the emission of carbon dioxide in accordance with the resolution of the kyoto protocol. Further, a product which can be recycled, for example, gypsum, can be produced and utilized. Although the carbon capture device 60 is disposed before the gas emission treatment device 50 in fig. 1, this is merely an example and is not intended to be limiting. In fact, the positions of each other can be changed and exchanged.

In summary, the exhaust gas treatment device 1 comprises an iron-based catalytic reaction device 20, which is capable of treating the dehydrated exhaust gas G by its characteristics suitable for application in the liquid phase_LThe catalytic reaction of the catalyst is continuously carried out under the condition of containing moisture. Therefore, the problem that the reaction rate is reduced because of the generation of catalyst poisoning in the prior art is solved. Further, the tail gas G is sufficiently removed and treated by the method_WThe oxidizing gas in the exhaust gas to avoid the exhausted exhaust gas G containing components harmful to human body.

Although the present invention has been described with reference to the preferred embodiments, it is to be understood that the invention is not limited thereto, and that various changes and modifications can be made without departing from the spirit of the invention.

Claims

1. A tail gas treatment device for receiving and treating tail gas, comprising:

the demisting device is used for adsorbing water vapor in the treated tail gas and outputting dehydrated tail gas; and

and the iron-based catalyst reaction device is connected with the demisting device and used for receiving the dehydrated tail gas, and the iron-based catalyst reaction device comprises an iron-based catalyst and is used for catalytically reducing the oxidizing gas in the dehydrated tail gas to generate exhaust gas and then discharging the exhaust gas.

2. The exhaust gas treatment device according to claim 1, characterized in that:

the heating device is arranged between the demisting device and the iron-based catalyst reaction device, receives the dehydrated tail gas and heats the dehydrated tail gas.

3. The exhaust gas treatment device according to claim 2, characterized in that:

the device comprises a demister, a heating device, an iron-based catalyst reaction device and a heat exchanger, wherein the demister is arranged in the shell, the heat exchanger comprises a first gas flow channel and a second gas flow channel, one end of the first gas flow channel is connected with the demister so as to input the dehydrated tail gas, the other end of the first gas flow channel is connected with the heating device, one end of the second gas flow channel is connected with the iron-based catalyst reaction device so as to input the exhaust gas, and the exhaust gas and the dehydrated tail gas exchange heat in the heat exchanger.

4. The exhaust gas treatment device according to claim 1, characterized in that:

the moisture content in the dehydration tail gas is 0.5 to 15 wt%.

5. The exhaust gas treatment device according to claim 1, characterized in that:

the iron-based catalytic reaction device is connected with the iron-based catalytic reaction device, and the exhaust gas is further purified and then discharged.

6. The exhaust gas treatment device according to claim 5, characterized in that:

the gas emission treatment device is a washing tower or an adsorption device.

7. The exhaust gas treatment device according to claim 5, characterized in that:

the gas discharge processing device is a plasma processing device.

8. The exhaust gas treatment device according to claim 1, characterized in that:

the iron-based catalyst in the iron-based catalytic reaction device is in a solid state.

9. The exhaust gas treatment device according to claim 1, characterized in that:

the oxidizing gas is ozone.

10. The exhaust gas treatment device according to claim 1, characterized in that:

the device also comprises a carbon capture device which receives the exhaust gas, performs carbon fixation reaction and then discharges the exhaust gas.