TWM578189U - Low temperature catalyst denitration and dust removal equipment with ceramic fiber filter tube - Google Patents

Abstract

The invention relates to a low-temperature catalyst denitration and dust removal device with a ceramic fiber filter tube, which is suitable for removing dust and nitrogen oxides in an exhaust gas, and comprises a method suitable for mixing an amino reducing agent in the exhaust gas and forming the exhaust gas into a gas to be reduced. a pre-processing unit and a catalyst unit connected to the pre-processing unit. The catalyst unit includes at least one filter tube adapted for passage of the gas to be reduced, and a catalyst attached to the at least one filter tube. The catalyst has titanium oxide, vanadium oxide, molybdenum oxide and tungsten oxide, and when the gas to be reduced passes through the at least one filter tube, a reducing gas for removing dust and nitrogen oxides is formed. Through the low-temperature catalyst denitration and dedusting equipment with the ceramic fiber filter tube, the exhaust gas can be treated with good denitration efficiency without heating the exhaust gas.

Description

Low temperature catalyst denitration and dust removal equipment with ceramic fiber filter tube

The invention relates to a soot processing device, in particular to a low temperature catalytic denitration and dust removal device with a ceramic fiber filter tube for treating exhaust gas.

The boiler in the factory will generate exhaust gas with a temperature of up to 200 ° C to 1400 ° C after the combustion operation. In order to properly apply the heat energy in the exhaust gas, heat recovery of the exhaust gas is often performed, and the recovered heat energy is used for power generation. The temperature of the exhaust gas after heat recovery will usually fall below 200 °C, and the dust and nitrogen oxides need to be removed before it can be discharged to avoid environmental and air pollution.

Referring to Fig. 1, a conventional exhaust gas dedusting apparatus comprises a heater 81 suitable for heating the exhaust gas to 350 ° C, an electrostatic precipitator 82 suitable for adsorbing dust, and a method suitable for mixing the exhaust gas with an ammonia type agent. a honeycomb catalyst reaction device 83 for removing nitrogen oxides by a catalyst, a desulfurizer 84 suitable for removing sulfur element by mixing or washing the exhaust gas with water and limestone, and a gas desulfurizer 84 suitable for removing dust in the exhaust gas again. A non-woven filter 85, and an exhaust pipe 86 suitable for discharging the exhaust gas.

Since the catalyst used in the denitrator 83 is at a temperature of 250 In the environment of °C to 350 °C, good denitration efficiency can be obtained, so the heater 81 is required to heat the exhaust gas. In addition to the need to consume additional energy, the heated exhaust gas is more likely to cause the nonwoven filter 85 to be easily damaged by high temperatures and needs to be improved.

Therefore, the object of the present invention is to provide a low-temperature catalyst denitration and dedusting device with a ceramic fiber filter tube which can provide good denitration efficiency without heating the exhaust gas.

Therefore, the novel low-temperature catalyst denitration and dedusting device with a ceramic fiber filter tube is suitable for removing dust and nitrogen oxides in an exhaust gas, and comprises a method suitable for mixing an amino reducing agent in the exhaust gas and forming the exhaust gas into a gas. a pretreatment unit for the gas to be reduced, and a catalyst unit connected to the pretreatment unit. The catalyst unit includes at least one filter tube adapted for passage of the gas to be reduced, and a catalyst attached to the at least one filter tube. The catalyst has titanium oxide, vanadium oxide, molybdenum oxide and tungsten oxide, and when the gas to be reduced passes through the at least one filter tube, a reducing gas for removing dust and nitrogen oxides is formed.

The utility model has the advantages that the exhaust gas which is heat-recovered is not required to be heated again, and the catalyst unit can remove dust and nitrogen oxides in the exhaust gas with good efficiency, can reduce energy consumption, and can avoid the catalyst. The unit is damaged by high temperatures, which saves equipment costs.

2‧‧‧Desulfurization unit

3‧‧‧Pre-processing unit

4‧‧‧catalyst unit

41‧‧‧ filter tube

411‧‧‧ openings

42‧‧‧ catalyst

5‧‧‧burning unit

6‧‧‧Exhaust unit

Other features and effects of the present invention will be apparent from the following description of the drawings, wherein: FIG. 1 is a schematic diagram illustrating a conventional exhaust gas dedusting apparatus; FIG. 2 is a schematic view showing the present invention having a ceramic fiber An embodiment of a low temperature catalytic denitration and dedusting apparatus for a filter tube; and FIG. 3 is a schematic view showing a catalyst unit of the embodiment.

Referring to FIG. 2, an embodiment of the low temperature catalytic denitration and dust removal device with a ceramic fiber filter tube is suitable for removing dust and nitrogen oxides in an exhaust gas, and comprises a mixed desulfurizing agent suitable for the exhaust gas. And the exhaust gas forms a desulfurization unit of the desulfurized gas, a pretreatment unit 3 that communicates with the desulfurization unit 2, and a catalyst unit 4 that communicates with the pretreatment unit 3.

The desulfurization unit 2 is adapted to be connected to a combustion unit 5 for generating the exhaust gas, and is adapted to mix a desulfurizing agent in the exhaust gas, and absorb the sulfur oxide (SO _x ) in the exhaust gas by the desulfurizing agent, so that the desulfurization unit 2 The exhaust gas forms the desulfurized gas. In this embodiment, the desulfurizing agent is selected from the group consisting of limestone, dolomite, hydrated lime, or a calcium-based absorbent.

The pretreatment unit 3 is adapted to mix an amino reducing agent in the desulfurized gas to form the desulfurized gas to form the gas to be reduced. In this embodiment, the amino group is also The raw agent is selected from ammonia, urea, or ammonia.

Referring to FIG. 2 and FIG. 3, the catalyst unit 4 is adapted to be connected to a discharge unit 6 for discharging the reducing gas, and includes a plurality of filter tubes 41 which are spaced apart and are suitable for the passage of the gas to be reduced, and a filter unit The catalyst 42 attached to the filter tubes 41. Each of the filter tubes 41 has a plurality of ceramic fibers (not shown) which are interwoven and can withstand high temperatures, and are formed with an opening 411 facing the exhaust unit 6. In this embodiment, the catalyst 42 has a titanium oxide, a vanadium oxide, a molybdenum oxide, a tungsten oxide, a magnesium oxide, and a fluorine compound, and the catalyst 42 is attached to the filter tubes 41 by an impregnation method. The toxic nitrogen oxide (NO _x ) in the gas to be reduced is reacted with ammonia (NH ₃ ), and the nitrogen oxide is reduced to non-toxic nitrogen (N ₂ ) and water (H ₂ O).

In actual operation, the gas to be reduced will pass through the filter tubes 41 in the direction indicated by the arrow in Fig. 3, and flow from the openings 411 to the exhaust unit 6, during which the dust will be treated. The filter tube 41 is filtered out, and the nitrogen oxides are catalyzed by the catalyst 42 to react into nitrogen gas, so that the gas to be reduced forms the reducing gas in compliance with environmental emission standards. In this embodiment, the reducing gas is nitrogen and moisture. In addition to the larger particle size dust (Particulate Matter, PM for short), these filter tubes 41 can also effectively remove PM _2.5 grade dust (particles smaller than or equal to 2.5 microns). In an embodiment, the filter tubes 41 are capable of removing 80% to 99.9% of suspended particulates, and 50% to 95% of PM _2.5 grade dust.

In the catalyst unit 4, the reaction temperature is from 150 ° C to 250 ° C. Wherein, the denitration efficiency of the catalyst 42 is 70% to 95% at 150 ° C to 200 ° C, and the denitration efficiency of the catalyst 42 can reach 90% to 99% at 200 ° C to 225 ° C. The catalyst 42 has a denitration efficiency of 95% to 100% at 225 ° C to 250 ° C. Since the vanadium oxide of the catalyst 42 catalyzes the nitrogen oxides, the sulfur dioxide (SO ₂ ) in the gas to be reduced is also oxidized to sulfur trioxide (SO ₃ ), in an environment below 320 ° C, Sulfur trioxide readily reacts with ammonia to produce a viscous ammonium hydrogen sulfate (NH ₄ HSO ₄ ) which, when adhered to the catalyst unit 4, shields the catalyst unit 4 and causes the catalyst 42 loses activity, which in turn affects the efficiency of nitrogen oxide removal. Therefore, the sulfur oxides in the exhaust gas must be removed as much as possible by the desulfurization unit 2 to avoid the production of ammonium hydrogen sulfate.

In the present embodiment, the catalyst 42 has a weight percentage of 80 wt% to 90 wt% of titanium oxide, and a weight percentage of 1 wt% to 7 wt% of vanadium oxide, based on 100 wt% of the total weight of the catalyst 42. The weight percentage is from 1 wt% to 10 wt% of molybdenum oxide, from 1 wt% to 10 wt% of tungsten oxide, from 0.1 wt% to 5 wt% of magnesium oxide, and from 0.1 wt% to 5 wt% by weight. Fluorine compound. However, in practical applications, the catalyst 42 may also have only titanium oxide, vanadium oxide, molybdenum oxide, and tungsten oxide, and the proportion of the composition of the catalyst 42 may be appropriately adjusted according to the execution requirements, instead of The above ratio is limited, and the effect of removing nitrogen oxides can also be achieved.

It should be specially stated that the new type of low temperature catalyst strip with ceramic fiber filter tube The deniturization device may also include only the pre-processing unit 3 and the catalyst unit 4, and the catalyst unit 4 may also include only a filter tube 41 and a catalyst 42 to remove dust and nitrogen oxides in the exhaust gas. .

In summary, the novel low-temperature catalyst denitration and dedusting device having a ceramic fiber filter tube is made of ceramic fiber by using a catalyst 42 capable of performing denitration reaction in an environment of 150 ° C to 250 ° C. The filter tubes 41 do not need to reheat the heat-recovered exhaust gas, and the catalyst unit 4 can remove dust and nitrogen oxides in the exhaust gas with good efficiency. The energy consumption can be reduced, and the catalyst unit 4 can be prevented from being damaged by high temperature, and the equipment cost can be saved, so that the purpose of the present invention can be achieved.

However, the above is only the embodiment of the present invention, and when it is not possible to limit the scope of the present invention, all the simple equivalent changes and modifications according to the scope of the patent application and the contents of the patent specification are still This new patent covers the scope.

Claims (7)

The invention relates to a low-temperature catalytic denitration and dust removal device with a ceramic fiber filter tube, which is suitable for removing dust and nitrogen oxides in an exhaust gas, and comprises: a pre-processing unit, suitable for mixing an amino reducing agent in the exhaust gas to make the exhaust gas Forming a gas to be reduced; and a catalyst unit connected to the pretreatment unit, and including at least one filter tube suitable for the passage of the gas to be reduced, and a catalyst attached to the at least one filter tube, the catalyst The titanium oxide, the vanadium oxide, the molybdenum oxide and the tungsten oxide are used to form a reducing gas for removing dust and nitrogen oxides when the gas to be reduced passes through the at least one filter. The invention relates to a low-temperature catalytic denitration and dust removal device with a ceramic fiber filter tube, which is suitable for removing dust and nitrogen oxides in an exhaust gas, and comprises: a desulfurization unit, which is suitable for mixing a desulfurizing agent in the exhaust gas to make the exhaust gas Forming a desulfurized gas; a pretreatment unit, communicating the desulfurization unit, and being adapted to mix the amino reducing agent in the desulfurized gas to form the desulfurized gas to form a gas to be reduced; and a catalyst unit Connecting the pretreatment unit, and including at least one filter tube suitable for the passage of the gas to be reduced, and a catalyst attached to the at least one filter tube, the catalyst having titanium oxide, vanadium oxide, molybdenum oxidation And the tungsten oxide, when the gas to be reduced passes through the at least one filter tube, forming a reducing gas for removing dust and nitrogen oxides. The low temperature catalytic denitration and dedusting apparatus having a ceramic fiber filter according to claim 1 or 2, wherein the at least one filter tube has a plurality of ceramic fibers interwoven with each other. The low-temperature catalyst denitration and dedusting apparatus having a ceramic fiber filter according to claim 1 or 2, wherein the catalyst further has magnesium oxide and a fluorine compound. The low temperature catalyst denitration and dedusting device having a ceramic fiber filter tube according to claim 4, wherein the catalyst has a titanium oxide and a weight percentage of 60 wt% to 100 wt% of the total weight of the catalyst. 90wt%; vanadium oxide, 0.1% by weight to 10% by weight; molybdenum oxide, 1% by weight to 20% by weight; tungsten oxide, 1% by weight to 20% by weight; magnesium oxide, by weight 0.1% by weight to 10% by weight; and a fluorine compound in a weight percentage of 0.1% by weight to 10% by weight. The low-temperature catalyst denitration and dedusting device having a ceramic fiber filter tube according to claim 1 or 2, wherein the catalyst unit comprises a plurality of filter tubes disposed at intervals and adapted for passage of the gas to be reduced, and an attached The catalyst of these filter tubes. The low-temperature catalyst denitration and dedusting device having a ceramic fiber filter tube according to claim 6, wherein each of the filter tubes has a plurality of ceramic fibers interwoven with each other.