KR20090034031A - Method and apparatus for removing nasty smell from exhaust gas using bag filter - Google Patents

Abstract

A method and an apparatus for removing odor from an exhaust gas using a bag filter are provided to remove bad smell materials of many kinds at the same time and to use a filter of the bag filter semi-permanently without exchanging the bag. A method for removing odor from an exhaust gas using a bag filter includes the following steps of: forming a filter protection layer(155) on a surface of a nonwoven fabric bag(152) by supplying filter protection powder in the bag filter while discharging air of the bag filter(150); forming an adsorbent layer(156) on the surface of the filter protection layer; and removing bad smell included in exhaust gas by passing layers in order of precedence.

Description

METHOD AND APPARATUS FOR REMOVING NASTY SMELL FROM EXHAUST GAS USING BAG FILTER}

The present invention relates to a method and apparatus for removing odor contained in exhaust gas by using a bag filter. More specifically, the present invention is a method and apparatus for making a nonwoven bag of a bag filter to act as a support, attaching filter protective powder to form a filter protective layer, and attaching an adsorbent powder to form an adsorbent layer to remove odor contained in exhaust gas. It is about.

Odors contained in the exhaust gas are classified into water-soluble odors, alkaline odors, acidic odors, and volatile organic compounds (VOCs) according to odor components. Alkaline odors are usually generated in manufacturing processes using caustic soda and the odor concentration is not very high. Water-soluble odors are removed by spraying the scrubber with water, and when it is desired to remove acidic odors and water-soluble odors at the same time, the odorous substances are removed by reaction by direct contact with an alkali solution mixed with caustic soda. Odors caused by volatile organic compounds (VOC) are usually removed by combustion when they are released at high concentrations. When volatile organic compounds (VOC) are discharged at low concentrations, they are usually removed using activated carbon adsorption towers, but when used for a long time, the odor adsorption capacity of activated carbon is exceeded and adsorption is prevented (called technical breakthrough in technical terms). There is a problem.

Ceramic filters are also used to remove odors. Ceramic filters may be manufactured by sintering ceramic powder in a uniform form, or by inserting ceramic powder into a fabric bag and inserting it into a stainless steel perforated network. Ceramic filter is used for the catalyst of hot gas, but when used for a long time, the pores are clogged and the reaction force of the catalyst has to be replaced because it is not used to remove the odor of the exhaust gas containing a lot of dust.

Until now, a technique for simultaneously removing various kinds of odors by using a bag filter is not known. In particular, no odor removal method or apparatus has been developed that can simultaneously remove odors caused by acidic or alkaline odors or volatile organic compounds (VOCs) contained in the exhaust gas using a bag filter.

An object of the present invention is to provide a method and apparatus for simultaneously removing various types of odorous substances contained in exhaust gas by attaching ceramic powder to the surface of a nonwoven bag using a nonwoven bag of a bag filter as a supporting member. do. In addition, an object of the present invention is to provide a method and apparatus that can be used semi-permanently without removing the bag of the bag filter to remove the odor contained in the exhaust gas.

According to one aspect of the present invention, there is provided a method for odorizing exhaust gas by supplying a filter protective powder having a neutral porosity of 70% or more while discharging air inside the bag filter so that the filter protective powder is attached to the surface of the nonwoven bag of the bag filter. Forming a filter protective layer, supplying an adsorbent powder so that adsorbent powder adheres to the surface of the filter protective layer, and forming an adsorbent layer, and exhaust gas to remove odor contained in the exhaust gas. It characterized in that it comprises a malodor removing step of sequentially passing through the adsorbent layer and the filter protective layer formed on the bag.

According to the present invention, since the filter protective powder is neutral, it does not react with the exhaust gas and absorbs moisture, but does not become gypsum, and because the porosity is large, the exhaust gas passes smoothly and the pores are not easily blocked by dust. If the adsorption capacity of the adsorbent layer decreases due to prolonged use, or the pressure loss of the bag filter increases due to clogging of the filter protective layer or the adsorbent layer, the adsorbent layer is easily removed from the nonwoven bag together with the filter protective layer attached to the surface of the nonwoven bag. Since it can fall out, the nonwoven bag of a bag filter can be used semi-permanently. In addition, when the component of the adsorbent powder is appropriately selected according to the odor component contained in the exhaust gas, it is possible to remove the odor contained in various kinds of exhaust gas.

In addition, the odor removal method of the exhaust gas according to the present invention, if the exhaust gas is an acidic or alkaline gas, by attaching a reactant powder for neutralization and discharged on the surface of the adsorbent layer or the surface of the filter protective layer to form a reactive layer The process may further include.

In the present invention, the filter protective powder is silica 69 wt% ~ 79.5 wt%, alumina 10.9 wt% ~ 17 wt%, potassium oxide 0.5 wt% ~ 6.4 wt%, sodium oxide 1.5 wt% ~ 5.5 wt%, calcium oxide 0.1 wt% to 3.0 wt%, iron oxide 0.1 wt% to 2.0 wt%, and magnesium oxide preferably 0.1 wt% to 1.0 wt%. In addition, the adsorbent powder, it is preferable to include at least one material selected from acidic clay, loess, diatomaceous earth, activated carbon, bentonite, silica gel, starch, zeolite, pearlite, activated alumina, silica, titanium oxide, metal oxide, ion exchange resin. Do.

In the present invention, when the exhaust gas is an acid gas, the reactant powder is calcium or magnesium-based dolomite, limestone, hydrated lime, limestone, lime, calcium sulfite, gypsum, iron hydroxide, iron chloride, basic coal, ion exchange resin It is preferable to include at least one material selected from among. In addition, in the present invention, when the exhaust gas is an alkaline gas, the reactant powder preferably includes at least one material selected from acidic clay, impregnated activated carbon (sulfonated coal, acid impregnated coal), and ion exchange resin.

According to another aspect of the present invention, there is provided an apparatus for removing odor of exhaust gas, comprising: a bag filter including a nonwoven bag, a filter protective layer formed by attaching a filter protection powder having a porosity of neutral and greater than 70% to the surface of the nonwoven bag; And an adsorbent layer formed by adsorbent powder adhering to the surface of the filter protective layer, wherein the filter protective layer and the adsorbent layer are attached by a negative pressure formed on the bag filter. In the present invention, it may further include a reactant layer formed by attaching a reactant powder for neutralizing the exhaust gas on the surface of the filter protective layer or the adsorbent layer.

According to the present invention, by using a nonwoven bag of a bag filter as a support member, a method and an apparatus capable of simultaneously removing various kinds of odorous substances contained in exhaust gas by attaching ceramic powder to the surface of the nonwoven bag are provided. In addition, the present invention provides a method and apparatus that can be used semi-permanently without removing the bag of the bag filter to remove the odor contained in the exhaust gas. In particular, according to the present invention, it is possible to reduce the installation cost and maintenance cost of the odor prevention facility by providing a method and apparatus capable of simultaneously removing acidic or alkaline odors and odors caused by volatile organic compounds (VOCs) using a bag filter. Will be. In particular, since it uses a filter protective powder that is not gypsum, it is economical to be able to use the non-woven fabric of the bag filter semi-permanently.

The embodiments of the present invention described above and illustrated in the drawings should not be construed as limiting the technical spirit of the present invention. The protection scope of the present invention is limited only by the matters described in the claims, and those skilled in the art can change and change the technical idea of the present invention in various forms. Therefore, such improvements and modifications will fall within the protection scope of the present invention, as will be apparent to those skilled in the art.

Hereinafter, with reference to the accompanying drawings, it will be described in detail with respect to the odor removal method and apparatus of the exhaust gas according to the present invention.

1 is a schematic diagram of an apparatus for explaining a method for removing odor of exhaust gas using a bag filter according to the present invention.

Referring to FIG. 1, a plurality of nonwoven fabric bags 152 are installed in the housing 158 of the bag filter 150, and an inlet 158a of the bag filter 150 is connected to a duct 154 and an outlet thereof. 158b is connected to the blower 160 through the duct 161. The blower 160 sucks the gas inside the bag filter 150 and discharges it to the chimney 170. A baffle 151 is provided between the inlet 158a and the nonwoven fabric bag 152. The duct 154 is connected with a hopper 140 for supplying the filter protective powder, a hopper 141 for supplying the adsorbent powder, and a hopper 142 for supplying the reactant powder, respectively. Although not shown, a screw conveyor for pulverizing and transporting powder is installed at the bottom of each hopper 140, 141, 142. The pneumatic system may be supplied to the duct 154 instead of the screw conveyor.

On the surfaces of the plurality of nonwoven bags 152, powder is sequentially supplied from each of the hoppers 140, 141, and 142 in a state in which negative pressure is applied to the inside of the nonwoven bag 152 by the operation of the blower 160. The filter protective agent layer 155, the adsorbent layer 156, and the reactive agent layer 157 are laminated | stacked and formed. The filter protective powder is neutral, has a low specific gravity of about 70-100 kg / m 3, has a porosity of 70% or more, and can be any powder having a property of not being gypsumized even when water is absorbed. The filter protective powder used in this embodiment is silica (SiO ₂ ), which is a drying / moisture agent, alumina (Al ₂ O ₃ ), which is a adsorption / dehydrating agent, potassium oxide (K ₂ O), which is a catalyst that reacts with water, and reduction / Sodium oxide (Na ₂ O) as a catalyst, calcium oxide (CaO) as a water trapping / drying agent, iron oxide (Fe ₂ O ₃ ) as a water adsorbent, and magnesium oxide (MgO) are included. Each component powder is composed of 69 wt% to 79.5 wt% silica, 10.9 wt% to 17 wt% alumina, 0.5 wt% to 6.4 wt% potassium oxide, 1.5 wt% to 5.5 wt% sodium oxide, 0.1 wt% to 3.0 calcium oxide It is preferable to have a mixing ratio of wt%, iron oxide 0.1 wt% to 2.0 wt%, and magnesium oxide 0.1 wt% to 1.0 wt%. The technology disclosed in Korean Patent No. 0613304, which is registered and registered by the inventor of the present invention as a filter protection powder, is incorporated as part of the present invention.

In addition, the adsorbent powder may be various kinds of metal oxides such as acid clay, loess, diatomaceous earth, activated carbon, bentonite, silica gel, starch, zeolite, pearlite, activated alumina, silica, titanium oxide and the like, depending on the odorous substances contained in the exhaust gas. At least one or more materials of the composite powder and the ion exchange resin may be sequentially supplied and laminated or mixed.

In addition, when reactant powder is removed by reacting and removing odor contained in acidic exhaust gas, calcium or magnesium dolomite, limestone, hydrated lime, limestone, lime, calcium sulfite, gypsum, iron hydroxide, iron chloride, base coal, ion exchange At least one or more materials of the resin may be laminated and used or mixed. In addition, when the odor contained in the alkaline exhaust gas is reacted and removed, at least one or more substances of acidic clay, impregnated activated carbon (sulfonated coal, acid impregnated carbon) and ion exchange resin may be sequentially supplied and laminated or mixed. have.

Under the housing 158 of the bag filter 150, the filter protection layer 155, the adsorbent layer 156 and the reactant layer 157 which are dropped from the nonwoven fabric bag 152 by the high pressure air of the compressor are discharged. An outlet 158c is formed. In addition, a rotary valve 153 is provided at the discharge port 158c. The rotary valve 153 includes a plurality of blades 153 formed at regular intervals along the circumferential direction, and filter protective powders, adsorbent powders, and reactions accumulated and dropped inside the bag filter by the rotation of the plurality of blades 153. The powder is discharged to the outside. The rotary valve 153 and the baffle 151 function to stack the filter protective layer 155, the adsorbent layer 156, and the reactant layer 157 on the surface of the nonwoven fabric bag 152 with a uniform thickness, respectively. . That is, when the filter protection powder, the adsorbent powder and the reactant powder are supplied into the housing 158, the blower 160 is operated while rotating the rotary valve 153 at a constant speed. The flowing powder rises on the upper air supplied intermittently to the gap C formed by the rotation of the rotary valve 153, and is uniformly attached to the plurality of nonwoven fabric filters 152. Reference numeral 153b is a reinforcement plate installed to adjust a gap between the housing and the blade and to prevent wear of the blade 153.

Hereinafter, a method of simultaneously removing acidic or alkaline odors and volatile organic compound (VOC) odors using an exhaust gas odor removal device as shown in FIG. 1 will be described.

First, the blower 160 connected to the bag filter 150 is operated to form a vacuum lower than atmospheric pressure in the housing 158 of the bag filter 150. Next, a certain amount of filter protective powder is supplied from the hopper 140 to the duct 154 to form the filter protective layer 155 on the surface of the nonwoven bag 152. Next, a predetermined amount of adsorbent powder is supplied from the hopper 141 to the duct 154 to form the adsorbent layer 156 on the surface of the filter protective layer 155. Next, a certain amount of reagent powder is supplied from the hopper 142 to the duct 154 to form the reagent layer 157 on the surface of the adsorbent layer 156. When supplying powder from each of the hoppers 140, 141, and 142, the rotary valve 153 is operated at the same time so that external air is intermittently supplied into the gap between the discharge hole 158c and the blade 153a. The powder is evenly attached to the surface of 152). In addition, the external air is supplied by the rotation of the rotary valve 153 to scatter the supplied powder to the upper side there is also an effect that can be attached to the nonwoven fabric filter 152 of the bag filter 150. When the process of attaching the filter protective layer 155, the adsorbent layer 156, and the reactant layer 157 is completed, the rotation of the rotary valve 153 is stopped.

Next, an exhaust gas containing an acidic or alkaline odor and a volatile organic compound (VOC) is introduced into the bag filter 150. Acidic or alkaline odor contained in the exhaust gas is first removed by the neutralization reaction while passing through the reactant layer 157, and volatile organic compounds (VOC), polar substances, and unsaturated while passing through the adsorbent layer 156 secondly. Substances and aromatics are removed by adsorption.

When the exhaust gas is treated for a long time, the air gap between the filter protection layer 155, the adsorbent layer 156, and the reactant layer 157 is clogged to increase the pressure loss of the bag filter 150. Air is supplied so that the filter protection layer 155 is detached from the surface of the nonwoven fabric 152 to separate the adsorbent layer 156 and the reactant layer 157 from the nonwoven fabric 152. The filter protection layer 155 is easily removed when a high pressure air such as a compressor is applied to the dust removal facility installed in the bag filter for dust removal because the gypsum does not proceed even if the moisture is absorbed. Therefore, the adsorbent layer 156 and the reactant layer 157 attached to the filter protective layer 155 are easily separated from the nonwoven fabric bag 152. Therefore, after dedusting, the filter protective powder, the adsorbent powder, and the reactant powder are reattached to the nonwoven fabric bag 152 as described above, and thus semi-permanently used without replacing the nonwoven fabric bag 152 of the bag filter. The technical content of the dust removal means for removing the dust attached to the nonwoven fabric bag 152 of the bag filter 150 belongs to a known technique and will not be further described.

1 is a schematic diagram of an apparatus for explaining a method for removing odor of exhaust gas using a bag filter according to the present invention.

<Brief Description of Drawings>

140, 141, 142 Powder Feed Hopper 150 Bag Filter

151 Baffle 152 Non Woven Bag

154 duct 155 filter protection layer

156 Adsorbent Layer 157 Reagent Layer

160 blower 170 chimney

Claims (14)

Discharging the air inside the bag filter to attach the filter protection powder to the surface of the nonwoven bag of the bag filter, and supplying the filter protection powder having a neutral porosity of 70% or more to form a filter protection layer; Supplying an adsorbent powder so that adsorbent powder adheres to the surface of the filter protective layer, and forming an adsorbent layer; And a malodor removing step of exhausting the exhaust gas sequentially passing through the adsorbent layer and the filter protection layer formed on the bag of the bag filter to remove the malodor contained in the exhaust gas. The method of claim 1, After the adsorbent layer forming process, the step of supplying the reactant powder so that the reactant powder for neutralizing the exhaust gas on the surface of the adsorbent layer to form a reactant layer, characterized in that it further comprises a step of forming a reactant layer How to remove. The method of claim 1, After the filter protective layer forming step, further comprising the step of supplying the reactant powder to attach the reactant powder to neutralize the exhaust gas on the surface of the filter protective layer to form a reactive layer characterized in that the exhaust gas How to get rid of odors. The method according to claim 2 or 3, The filter protective powder is silica 69 wt% ~ 79.5 wt%, alumina 10.9 wt% ~ 17 wt%, potassium oxide 0.5 wt% ~ 6.4 wt%, sodium oxide 1.5 wt% ~ 5.5 wt%, calcium oxide 0.1 wt% ~ 3.0 Wt%, iron oxide 0.1 wt% to 2.0 wt%, magnesium oxide 0.1 wt% to 1.0 wt% comprising the odor removal method of the exhaust gas. The method of claim 4, wherein The adsorbent powder is characterized in that it comprises at least one material selected from acidic clay, loess, diatomaceous earth, activated carbon, bentonite, silica gel, starch, zeolite, pearlite, activated alumina, silica, titanium oxide, metal oxide, ion exchange resin. How to remove odor of exhaust gas The method of claim 4, wherein The reactant powder is characterized in that it comprises at least one material selected from calcium or magnesium-based dolomite, limestone, hydrated lime, limestone, lime, calcium sulfite, gypsum, iron hydroxide, iron chloride, base coal, ion exchange resin How to remove odor from exhaust gas. The method of claim 4, wherein The reactant powder is odor removal method of the exhaust gas, characterized in that it comprises at least one material selected from acidic clay, impregnated activated carbon (sulfonated coal, acid impregnated coal), ion exchange resin. A bag filter comprising a nonwoven bag, A filter protective layer formed by attaching a filter protective powder that is neutral and has a porosity of 70% or more on the surface of the nonwoven fabric; An adsorbent layer formed by adsorbent powder adhering to a surface of the filter protective layer, The filter protection layer and the adsorbent layer is an odor removal device of the exhaust gas, characterized in that attached to the negative pressure formed in the bag filter. The method of claim 8, The apparatus for removing odor of exhaust gas, further comprising a reactant layer formed by attaching a reactant powder for neutralizing the exhaust gas on the surface of the adsorbent layer. The method of claim 8, An apparatus for removing odor of exhaust gas, further comprising a reactant layer formed by attaching a reactant powder for neutralizing the exhaust gas between the filter protective layer and the adsorbent layer. The method of claim 9 or 10, The filter protective powder is silica 69 wt% ~ 79.5 wt%, alumina 10.9 wt% ~ 17 wt%, potassium oxide 0.5 wt% ~ 6.4 wt%, sodium oxide 1.5 wt% ~ 5.5 wt%, calcium oxide 0.1 wt% ~ 3.0 Wt%, iron oxide 0.1 wt% to 2.0 wt%, magnesium oxide 0.1 wt% to 1.0 wt% comprising a odor removal device of the exhaust gas. The method of claim 11, The adsorbent powder is characterized in that it comprises at least one material selected from acidic clay, loess, diatomaceous earth, activated carbon, bentonite, silica gel, starch, zeolite, pearlite, activated alumina, silica, titanium oxide, metal oxide, ion exchange resin. Deodorizer of exhaust gas to be. The method of claim 11, The reactant powder is characterized in that it comprises at least one material selected from calcium or magnesium-based dolomite, limestone, hydrated lime, limestone, lime, calcium sulfite, gypsum, iron hydroxide, iron chloride, base coal, ion exchange resin Deodorizer of exhaust gas. The method of claim 11, The reactant powder may include at least one material selected from acidic clay, impregnated activated carbon (sulfonated coal, acid impregnated carbon), and ion exchange resin.

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