TWM628976U - Low temperature air pollution control system - Google Patents

Abstract

The present creation provides a low-temperature air pollution control system, comprising: an exhaust gas channel for entering an exhaust gas containing a particle. A cooling device is connected to the exhaust gas channel, and the operating temperature of the cooling device is between 300°C and 500°C. A scrubbing device is connected to the cooling device, and the scrubbing device scrubs the above _- mentioned exhaust gas, so that the temperature of the exhaust gas is reduced to below a saturated dew point of the exhaust gas. Different, its operating temperature is between 38 ℃ ~ 78 ℃, the water in the exhaust gas condenses into liquid water droplets, the particles form seed crystals and are washed and removed. A water removal device is connected to the washing device, and the water removal device separates the liquid water droplets in the exhaust gas to remove the droplets of the exhaust gas. A reheating device is connected to the water removing device, and the reheating device provides a reheating heat source for the exhaust gas to remove the white smoke problem of saturated water vapor. a dust collecting device connected to the reheating device, the dust collecting device collects the particles remaining in the exhaust gas, and adsorbs heavy metals, volatile organic pollutants, dioxins, persistent organic pollutants such as heavy metals by spraying activated carbon and remove the particulate pollutants and the aforementioned pollutants by the dust collecting equipment. An inducement fan is connected to the dust collecting device and a flue. The inducement fan assists the exhaust gas to enter from the exhaust gas channel, ensuring that the invention operates in a slightly negative pressure environment, and the inducement fan discharges the exhaust gas from the flue.

Description

Low temperature air pollution control system

This creation system provides a low-temperature air pollution control system, especially the use of cooling and washing methods to reduce the temperature of the exhaust gas to the saturation dew point of the exhaust gas, and then use the dust collection equipment to remove dust to increase the removal efficiency of acid, fine particles and heavy metals. A low-temperature air pollution control system that avoids the temperature at which dioxin is regenerated and reduces the amount of dioxin produced.

Chinese Patent Publication No. CN113551251A "A Cremator Tail Gas Purification System" discloses a cremator tail gas purification treatment system, including: a smoke exhaust pipe; a dual-fluid high-efficiency cooling reactor, a spark interception device, A pulse bag filter and a dioxin (dioxin) treatment device; a chimney arranged downstream of the dioxin (dioxin) treatment device, and the opening of the chimney faces the sky; an induced draft fan arranged downstream of the chimney, so The induced draft fan and the dioxin (dioxin) treatment device are respectively arranged on both sides of the chimney.

In addition, the exhaust gas generated by the existing heat treatment manufacturing (such as metal smelting, glass smelting, cement manufacturing, etc.) and waste heat treatment (such as incineration, melting) often contains acid, heavy metals, fine particles and other air pollutants. The methods used include: Wet waste gas treatment method and semi-dry waste gas treatment method.

The conventional wet waste gas treatment method is to remove various pollutants by using dust collection equipment and packed scrubbers after cooling or heat recovery of waste gas. The wet exhaust gas treatment method is to remove particulates first, and then remove acidic pollutants by wet scrubbing. Because the dust collection equipment is located before the wet scrubbing equipment, if the exhaust gas cooling effect is not good, it will cause the resynthesis of dioxin. Higher concentrations of air pollutants emitted.

As for the semi-dry waste gas treatment method, please refer to the first figure. The acid removal tower uses an atomizer to atomize the absorbent (such as liquid alkali or lime) slurry into small droplets with a diameter of about tens of microns, and these small droplets are combined with the waste gas to be treated in the acid removal tower. touch. When the small droplets reach the wall or bottom of the tower, all the water has evaporated into a dry powder state. A part of these dry powders can be separated from the bottom of the tower, and the rest can be handled by the dust collection equipment behind.

The above-mentioned current treatment methods of incinerator and furnace tail gas, coupled with increasingly strict regulations, make the treatment method of heat treatment tail gas unable to meet the increasingly strict regulatory standards, and in the process, the tail gas temperature is not particularly avoided from the dioxin generation temperature (250 ℃). ℃~400℃), and it is easy to regenerate dioxin.

Therefore, in order to solve the above-mentioned problems, the author proposes a low-temperature air pollution control system, which includes: an exhaust gas channel for entering an exhaust gas containing a particle; a cooling device connected to the exhaust channel, the operation of the cooling device The temperature is between 300 ° C and 500 ° C; a washing device is connected to the cooling device, and the washing device washes the above-mentioned exhaust gas, so that the temperature of the exhaust gas is reduced to below a saturation dew point of the exhaust gas, and the water in the exhaust gas is condensed into liquid water droplets, The particles form seeds and are washed and removed; a water removal device is connected to the washing device, and the water removal device separates the liquid water droplets in the exhaust gas; a reheat device is connected to the water removal device, and the reheat device is connected to the The exhaust gas provides a reheating heat source; a dust collecting device is connected to the reheating device, and the dust collecting device collects the particles remaining in the exhaust gas; an inducement fan is connected to the dust collecting device and a flue, the inducement fan will The exhaust gas is discharged from the flue.

Further, the cooling device is one of the following: a heat recovery unit, a water cooling unit or an air cooling unit.

Further, the water cooling unit includes a cooling liquid, and the cooling liquid is a recycled water or a supernatant liquid.

Further, the supernatant liquid contains a trace substance, and the trace substance is mixed in the exhaust gas, forms seed crystals in the washing device, and is washed and removed.

Further, the washing equipment includes a Venturi washing tower and a packed washing tower.

Further, the washing equipment includes a circulating water tank, and the circulating water tank is located below the Venturi washing tower and the packed washing tower.

Further, the operating temperature of the washing equipment is between 38°C and 78°C.

According to the above technical features, the following effects can be achieved:

1. Set up cooling equipment, so that the temperature of the exhaust gas at the outlet of the cooling equipment is controlled above 400 ℃, so as to avoid the exhaust gas staying at the dioxin generation temperature (250 ℃ ~ 400 ℃) for too long, and the dioxin will be regenerated.

2. The gas outlet temperature of the cooling equipment needs to be below the dew point of the acid-base exhaust gas of the treated exhaust gas. This is created when the exhaust gas temperature is lower than the critical temperature, and the water in the exhaust gas coexists in the form of gas and liquid, and its proportion is not fixed. When the water in the exhaust gas coexists in the form of gas and liquid, a small part of the gaseous water begins to condense to form liquid water droplets, and all the particles in the exhaust gas, especially the fine particles, will become seeds, which will be removed in the washing process after condensation. Then, through appropriate water removal equipment, the low-temperature exhaust gas with water vapor removed is introduced into the dust collection equipment for subsequent filtration treatment procedures.

1: exhaust channel

2: Quench tower

3: Venturi scrubber

4: Circulating water tank

5: Packed scrubber

6: Cyclone water separator

7: Heating buffer tank

8: Bag filter dust collector

9: Lure fan

91: flue

[The first figure] is a reference figure of the prior art semi-dry exhaust gas treatment system.

[The second figure] is a schematic diagram of an embodiment of the low-temperature air pollution control system of the present invention.

Combining the above technical features, the main effects of the low-temperature air pollution control system of the present invention will be clearly presented in the following embodiments.

Please refer to the second figure to illustrate the structure of the embodiment of the low-temperature air pollution control system of the present invention, including an exhaust gas channel 1, a quenching tower 2, a Venturi scrubber 3, a circulating water tank 4, a packed scrubber 5, and a cyclone water removal 6, heating buffer tank 7, bag filter 8, inducement fan 9, flue 91.

The exhaust gas is guided by the induced fan 9 and enters from the exhaust gas channel 1. The exhaust gas contains particles, and the type of exhaust gas includes the exhaust gas generated by the incineration equipment or the exhaust gas produced by the experimental waste liquid and the waste incinerator, but the type of the exhaust gas is not the same. limited.

The quench tower 2 is connected to the exhaust gas channel 1, and the exhaust gas is cooled by means of heat recovery, liquid cooling or washing, and its operating temperature is between 300°C and 500°C.

The bottom of the Venturi scrubbing tower 3 and the packed scrubbing tower 5 is connected to the circulating water tank 4, and the Venturi scrubbing tower 3 is connected to the quenching tower 2, and the tail gas is washed by the Venturi scrubbing tower 3, the circulating water tank 4, and the packed scrubbing tower 5. , the temperature of the exhaust gas is reduced to below the exhaust gas saturation dew point to remove air pollutants in the exhaust gas, and the exhaust gas saturation dew point varies according to the acid components (such as SO ₂ , HCl concentration) in the exhaust gas. Then the water in the exhaust gas condenses into liquid water droplets, and the particles in the exhaust gas form seeds and are washed and removed, thereby removing air pollutants in the exhaust gas. The operating temperature is between 38°C and 78°C.

The cyclone water remover 6 is connected to the packed washing tower 5, and the cyclone water remover 6 separates the liquid water droplets in the exhaust gas. The heating buffer tank 7 is connected to the cyclone water separator 6, and the heating buffer tank 7 provides a reheat heat source for the exhaust gas to remove the white smoke problem of saturated water vapor.

The bag filter type dust collector 8 is connected to the heating buffer tank 7. The bag filter type dust collector 8 collects the residual particles in the exhaust gas. The bag filter type dust collector 8 can remove the particles in the exhaust gas. Activated carbon is injected between the tank 7 and the bag filter 8, and the activated carbon adsorption capacity is used to absorb the pollutants contained in the exhaust gas. For some volatile heavy metals, or injecting activated carbon into the bag filter 8 to adsorb volatile heavy metals. Further, the unreacted absorbent can further react with other pollutants remaining in the exhaust gas, so that the treatment efficiency of the whole system can be further improved.

The induction fan 9 is connected to the bag filter 8 and the flue 91. The induction fan 9 assists the exhaust gas to enter from the exhaust passage 1 and is discharged from the flue 91, so that the present invention can filter the exhaust gas in a slightly negative pressure environment.

Continuing to explain the implementation of this creative example, after the exhaust gas enters the quenching tower 2 through the exhaust gas channel 1 to cool down, the temperature is between 300 ° C and 500 ° C, and then the exhaust gas will continue to go to the Venturi scrubber 3, the circulating water tank 4 and the filling type The washing tower 5, and the critical temperature (Critical point) of the water is 374 ℃, when the exhaust gas temperature is above 374 ℃, the water all exists in the gaseous state, when entering the Venturi washing tower 3, the circulating water tank 4 and the packed washing tower 5 After that, the outlet temperature dropped sharply to 58°C, which could reduce the residence time of the exhaust gas at the oxin generation temperature (250°C~400°C) and reduce the generation of dioxin. In addition, when the temperature of the exhaust gas entering the Venturi scrubber 3, the circulating water tank 4 and the packed scrubber 5 is lower than the critical temperature of water, a small part of the gaseous water begins to condense to form liquid water droplets, and all the particles in the exhaust gas, especially the fine particles, will It becomes a seed crystal, which is removed in the Venturi scrubber 3 and the packed scrubber 5 after condensation, and removes heavy metals and particulate matter in the exhaust gas. Table 1 is the embodiment of the air pollution control equipment sludge. and the pollutant concentration of the wastewater, Table 2 shows the comparison of the air pollutant discharge between the prior art of the embodiment and the present creation. As can be seen from Table 1, in the waste water of the Venturi washing tower 3 and the packed washing tower 5 and the bottom residue (sludge) thereof, a considerable amount of heavy metals and particulate matter are found, indicating that the present embodiment can remove a large amount of heavy metals and It can be seen from the comparison of the discharge amount of air pollutants between the prior art and the present invention in Table 2 that the present invention has a better removal effect for various air pollutants than the prior art.

Table 1 Concentration of pollutants in the residues of various air pollution control equipment in the embodiment

Generally, dioxin is a low-solubility pollutant. After the treatment in this embodiment, it passes through the Venturi washing tower 3, the circulating water tank 4, the packed washing tower 5 and the cyclone 6 before the bag filter 8, that is, There is a removal rate of close to 92.55% (calculated by I-TEQ). After the bag filter 8 injected with activated carbon, the removal effect is as high as 99.976%, and the overall dioxin removal rate is as high as 99.998% or more. , that is, the dioxin concentration change of the exhaust gas as revealed in Table 3.

Based on the descriptions of the above-mentioned embodiments, one can fully understand the operation, use and effects of the present creation, but the above-mentioned embodiments are only the preferred embodiments of the present creation, and should not limit the implementation of the present creation. The scope, that is, the simple equivalent changes and modifications made according to the scope of the patent application and the description of the creation, are all within the scope of the creation.

1: exhaust channel

2: Quench tower

3: Venturi scrubber

4: Circulating water tank

5: Packed scrubber

6: Cyclone water separator

7: Heating buffer tank

8: Bag filter dust collector

9: Lure fan

91: flue

Claims (7)

A low-temperature air pollution control system, comprising: a tail gas channel for entering a tail gas containing a particle; a cooling device connected to the tail gas channel, the operating temperature of the cooling device is between 300°C and 500°C; a washing device , connected to the cooling device, the washing device washes the above-mentioned exhaust gas, so that the temperature of the exhaust gas drops below a saturated dew point of the exhaust gas, the water in the exhaust gas condenses into liquid water droplets, and the particles form crystal seeds and are washed and removed; A water device, connected to the washing device, the water removal device separates the liquid water droplets in the exhaust gas; a reheat device, connected to the water removal device, the reheat device provides a reheat heat source for the exhaust gas; a dust collection device, connected to The reheating device, the dust collecting device collects the particles remaining in the exhaust gas; an induction fan is connected to the dust collecting device and a flue, and the induction fan discharges the exhaust gas from the flue. The low-temperature air pollution control system as claimed in claim 1, wherein the cooling device is one of the following: a heat recovery unit, a water cooling unit or an air cooling unit. The low-temperature air pollution control system as claimed in claim 2, wherein the water cooling unit comprises a cooling liquid, and the cooling liquid is a recovered water or a supernatant liquid. The low-temperature air pollution control system according to claim 3, wherein the supernatant liquid contains a trace substance, and the trace substance is mixed in the exhaust gas, forms seeds in the washing equipment, and is washed and removed. The low-temperature air pollution control system as claimed in claim 1, wherein the scrubbing device comprises a Venturi scrubber and a packed scrubber. The low-temperature air pollution control system according to claim 5, wherein the washing device comprises a circulating water tank, and the circulating water tank is located below the Venturi scrubber and the packed scrubber. The low-temperature air pollution control system as claimed in claim 1, wherein the operating temperature of the washing equipment is between 38°C and 78°C.

Images