JP6797384B1 - Exhaust gas treatment chemical manufacturing method, exhaust gas treatment method and exhaust gas treatment system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sodium carbonate production method for producing a porous sodium carbonate which is easy to handle and can efficiently remove an acidic component at a low cost. The method for producing sodium carbonate of the present invention is a method for producing porous sodium carbonate from baking soda, in which 70 to 200 μm of crude sodium carbonate is applied under a vacuum of 10 Pa to 5 kPa at 150 to 200 ° C. Has a step of heating in. Further, in the exhaust gas treatment method of the present invention, porous sodium carbonate produced by the step of heating 70 to 200 μm crude baking soda under a vacuum of 10 Pa to 5 kPa at 150 to 200 ° C. was generated by waste incineration. It has a step of blowing into the exhaust gas. [Selection diagram] Fig. 2

Description

The present invention relates to a method for producing an exhaust gas treatment chemical, an exhaust gas treatment method, and an exhaust gas treatment system, and in particular, highly efficiently produces harmful acid gases such as hydrogen chloride (HCl) and sulfur oxide (SOx) generated when waste is incinerated. Regarding the technique for removing with.

Exhaust gas generated by incineration of municipal waste and industrial waste contains harmful acid gases such as hydrogen chloride (HCl) and sulfur oxides (SOx), and such harmful substances remain as they are. When it is discharged into the atmosphere, it causes damage to the environment.

As a method for neutralizing and removing these harmful acidic components, two means, a dry method and a wet method, are used.

The wet method has been adopted when the regulation value is strict because of its high efficiency of removing acidic components, but it has recently been adopted because it takes time and effort to maintain the equipment used and the maintenance cost is high. There are few examples.

On the other hand, the dry method is widely adopted because the equipment used is simple and maintenance is easy. Until now, slaked lime has been used as a chemical in the dry method, and as a method of using slaked lime, there is a continuous blowing method or a precoat method.

The continuous injection method is a method in which slaked lime is continuously blown into the inlet flue of a bag filter or the like, but the reaction efficiency of slaked lime is low, and generally 1.3 times the required amount of chemicals (equivalent ratio 1.3). ), It is said that the removal rate is about 60 to 90%, and in order to remove it below the regulation value, excess slaked lime must be blown. In addition, since fly ash collected by a dust collector such as a bug filter is treated as specially controlled waste, it is necessary to perform stabilization treatment with a chemical such as chelate and then bury it in a controlled disposal site. There is also a problem that the amount of fly ash collected increases by blowing excess slaked lime, the final disposal cost increases, and it takes time to stabilize the disposal site.

In the precoat type, slaked lime is blown into the flue at the inlet of the bag filter at once for a predetermined time to form a reaction layer of slaked lime on the filter cloth, and a higher removal rate can be obtained as compared with the above continuous blowing type. However, there is a problem that the amount of slaked lime used increases because the concentration is removed to a concentration lower than the regulated value.

In this way, the method using slaked lime in the dry method causes problems associated with low efficiency, so a method using sodium hydrogen carbonate (baking soda) with higher removal efficiency has been proposed, and baking soda is used. There are two methods, one is a fine crushing blow type and the other is a fine crushing type just before coarse baking soda.

In the finely pulverized blowing type, baking soda finely pulverized to about 20 μm is blown into the inlet flue of a bag filter or the like like slaked lime, and a high removal rate of 98% can be obtained with an equivalent ratio of 1.3. Here, the unadjusted baking soda has a particle size of about 70 to 200 μm, and the efficiency is low even if it is blown as it is. Therefore, the reaction efficiency is improved by finely pulverizing to about 20 μm, but the cost for fine pulverization is high. The problem arises. In addition, the finely pulverized baking soda has poor fluidity, and new problems such as a bridge phenomenon in the storage tank and poor discharge from the storage tank occur. When a chemical or the like for preventing these problems is mixed, the finely pulverized baking soda is pulverized. There is a problem that the price is several times higher than that of the previous baking soda.

The pulverization method immediately before the coarse baking soda is a method for solving the above-mentioned problems of the pulverization blowing type, and the crude baking soda is cut out from the storage tank and put into a crusher immediately before being blown into the inlet flue such as a bug filter. It is blown into the inlet flue while being finely pulverized to about 20 μm, and there is no problem such as a bridge in the storage tank. However, there are problems such as it is difficult to crush stably to a particle size of about 20 μm, which is said to be efficient against changes in the amount of baking soda blown, and it takes time and effort to maintain the crusher. is there.

In order to deal with this problem, a method of producing porous sodium carbonate having a high reaction rate and treating the exhaust gas has been proposed. (Patent Document 1)

Patent No. 4841065

According to the technique disclosed in Patent Document 1, efficient acidity is achieved by using porous sodium carbonate produced by finely pulverizing baking soda and blowing the finely pulverized baking soda into exhaust gas for exhaust gas treatment. The components can be removed. However, the technique disclosed in Patent Document 1 is a technique using a wet method, and a separate device for finely pulverizing baking soda is required, so that maintenance of the device to be used is troublesome. However, there was a problem that maintenance costs were high.

The present invention has been made in view of such a problem, and a method for producing a drug which is easy to handle, can efficiently remove acidic components at a low price, and a method for treating exhaust gas using this drug. The purpose is to provide.

The present invention provides the following solutions.

The invention according to the first feature is a method for producing a porous sodium carbonate from baking soda, which comprises a step of heating 70 to 200 μm of crude baking soda under vacuum at 150 to 200 ° C. ..

According to the invention according to the first feature, by heating crude baking soda under vacuum at 150 to 200 ° C., porous sodium carbonate having a high reaction rate can be produced.

The invention according to the second feature provides an exhaust gas treatment method having a step of blowing porous sodium carbonate produced by the exhaust gas treatment chemical manufacturing method according to the first feature into the exhaust gas generated by waste incineration. To do.

According to the invention according to the second feature, it is possible to provide an exhaust gas treatment method capable of removing an acidic component with a high removal rate by blowing the produced porous sodium carbonate into the exhaust gas.

The invention according to the third feature treats the exhaust gas discharged from the waste incinerator in a waste incinerator that incinerates waste and a waste incinerator having a chemical generation tank that generates a chemical that blows into the exhaust gas. It is an exhaust gas treatment method, in which a crude sodium bicarbonate having an average particle size of 70 to 200 μm is stored in a chemical generation tank, a step of recovering heat from a waste incinerator, and a pressure in the chemical generation tank is 10 Pa to 5 kPa. By supplying the heat recovered from the waste incinerator to the chemical generation tank in the step of vacuum exhausting, the crude baking soda is heated at 150 to 200 ° C. in the chemical generation tank held in the vacuum to produce porous sodium carbonate. It has a step of producing and a step of blowing the produced porous sodium carbonate into the exhaust gas.

According to the invention according to the third feature, since the crude baking soda is heated under vacuum by using the heat recovered from the waste incinerator, porous sodium carbonate can be produced without using a separate heating device. By blowing the produced porous sodium carbonate into the exhaust gas, it is possible to provide an exhaust gas treatment method capable of removing an acidic component with a high removal rate.

According to the present invention, it is possible to provide a method for producing a drug which is easy to handle and can efficiently remove acidic components at a low cost, and a method for treating exhaust gas using the drug.

FIG. 1 is a schematic view showing a sodium carbonate production apparatus according to the present embodiment. FIG. 2 is a flowchart showing a procedure for producing sodium carbonate according to the present embodiment. FIG. 3 is a schematic view showing a waste incineration facility including an exhaust gas treatment system according to the present embodiment. FIG. 4 is a flowchart showing an exhaust gas treatment procedure according to the present embodiment.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. It should be noted that this is only an example, and the technical scope of the present invention is not limited to this.

[Sodium carbonate production equipment configuration]
The configuration of the sodium carbonate production apparatus according to the present embodiment will be described with reference to FIG.

As shown in FIG. 1, the sodium carbonate production apparatus of the present embodiment includes a sodium carbonate generation tank 1, a crude baking soda supply device 2, a vacuum exhaust device 3, a heating device 4, and a discharge device 5. ..

The sodium carbonate generation tank 1 is composed of a container having a structure capable of withstanding a vacuum state of 10 Pa to 5 kPa and a temperature of 150 to 200 ° C., a crude baking soda supply device 2 for supplying crude baking soda upward, and a crude sodium carbonate supply device 2 below. A discharge device 5 for discharging the generated porous sodium carbonate is connected. The sodium carbonate generation tank 1 temporarily stores the crude baking soda supplied by the crude baking soda supply device 2, and discharges the generated porous sodium carbonate by the discharge device 5.

The crude baking soda supply device 2 comprises well-known supply means such as a conveyor and a chute (not shown), and smoothly supplies crude baking soda having an average particle size of 70 to 200 μm to the sodium carbonate generation tank 1 without causing clogging or agglomeration. You can do it.

The vacuum exhaust device 3 is composed of well-known exhaust means such as a vacuum pump and an exhaust blower, and has a function of holding the inside of the sodium carbonate generation tank 1 in a vacuum state of 10 Pa to 5 kPa.

The heating device 4 is composed of well-known heating means such as a heater and a heat transfer tube, and has a function of uniformly heating the inside of the sodium carbonate generation tank 1 to 150 to 200 ° C. Since the inside of the sodium carbonate generation tank 1 is maintained in a vacuum state, a heating means in which hot gas is directly blown is not suitable, and the composition and capacity of the gas in the sodium carbonate generation tank 1 are sudden. A non-variable type of heating means is desirable.

The discharge device 5 is composed of a conveyor or the like connected to the lower end of the sodium carbonate generation tank 1, and the porous sodium carbonate produced in the sodium carbonate generation tank 1 is not clogged or aggregated. It can be discharged smoothly. In addition, a portable tank or the like for storing the generated porous sodium carbonate may be provided, and the generated porous sodium carbonate may be filled and then brought into a waste treatment facility.

[Procedure for producing porous sodium carbonate]
Next, the procedure for producing porous sodium carbonate according to the present embodiment will be described with reference to the flowchart shown in FIG.

[Step S100: Supply of crude baking soda]
First, the crude baking soda supply device 2 is started to supply the crude baking soda having an average particle size of 70 to 200 μm into the sodium carbonate generation tank 1 (step S100).

At this time, the discharge device 5 is not activated, and the crude baking soda can be temporarily stored in the sodium carbonate generation tank 1.

At that time, since the average particle size of the crude baking soda is about 70 to 200 μm, unlike the finely pulverized baking soda, the crude baking soda has good fluidity and is smoothly supplied without causing a bridge in the sodium carbonate generation tank 1. To.

[Step S110: Vacuum exhaust in the sodium carbonate generation tank]
When the crude baking soda is supplied in step S100, the vacuum exhaust device 3 is then activated to exhaust the inside of the sodium carbonate generation tank 1 filled with the crude baking soda so as to be in a vacuum state of 10 Pa to 5 kPa (step S110). ).

At this time, since the crude baking soda in the sodium carbonate generation tank 1 has an average particle size of about 70 to 200 μm, it is not sucked into the vacuum exhaust device 3, that is, without causing clogging of the vacuum exhaust device 3. The inside of the sodium carbonate generation tank 1 can be evacuated to a vacuum.

[Step S120: Heating in the sodium carbonate generation tank]
When the vacuum exhaust in the sodium carbonate generation tank 1 is completed in step S110, the heating device 4 is then started to heat the crude baking soda to 150 to 200 ° C. (step S120).

At this time, in the sodium carbonate production tank 1, the following reaction represented by the formula (1) occurs by heating crude baking soda having an average particle size of 70 to 200 μm to 150 to 200 ° C. under a vacuum of 10 Pa to 5 kPa. , H ₂ O and CO ₂ are released from the baking soda represented by NaHCO ₃ , and sodium carbonate is produced from the crude baking soda.
_{2NaHCO 3 → Na 2 CO 3 +} H 2 O + CO 2 ···· formula (1)

[Step S130: Discharge of sodium carbonate]
When the porous sodium carbonate is generated in step S120, the heating device 4 and the vacuum exhaust device 3 are stopped, the discharge device 5 is started, and the sodium carbonate generated from the sodium carbonate generation tank 1 is discharged ( Step S130), the production of sodium carbonate is completed.

At this time, since the produced sodium carbonate has an average particle size of 70 to 200 μm, it can be smoothly discharged from the sodium carbonate generation tank 1 without causing a bridging phenomenon or discharge failure.

The porous sodium carbonate produced in this way is brought into the waste treatment facility and blown into the exhaust gas from the exhaust gas flue by a separate blowing device, whereby the formulas (2) and (3) are used. The following reactions shown occur.
Na ₂ CO ₃ + 2HCl → 2 NaCl + H ₂ O + CO ₂ ... Equation (2)
Na ₂ CO ₃ + SO ₂ + 1 / 2O ₂ → Na ₂ SO ₄ + CO ₂ ... Equation (3)

That is, when sodium carbonate reacts with hydrogen chloride, hydrogen chloride is neutralized, sodium chloride, water and carbon dioxide are generated, and sodium carbonate reacts with sulfur dioxide and oxygen to neutralize sulfur dioxide. , Sodium sulfate and carbon dioxide are produced.

Here, in Table 1, the ratio of uncrushed baking soda (crude baking soda) heated under atmospheric pressure, fine powdered sodium bicarbonate heated under atmospheric pressure, and crude baking soda according to the present embodiment heated under vacuum Indicates the surface surface, pore diameter, and pore volume.

According to Table 1, the porous sodium carbonate produced by the production procedure according to the present embodiment has a specific surface area of 2 times or more and 10 times or more of total fineness as compared with the case where crude baking soda is simply heated under atmospheric pressure. It can be seen that it has a much higher removal efficiency because it has a pore volume. Further, it can be seen that the specific surface area and the total pore volume are larger than those of the finely pulverized baking soda heated under atmospheric pressure, and the removal efficiency is higher than that of the finely pulverized baking soda. Further, unlike the finely pulverized one, since the average particle size is 70 to 200 μm, problems such as bridging and poor discharge in the storage tank do not occur, and no device for pulverization is required. By using the porous sodium carbonate produced by the production procedure according to the above as a chemical for exhaust gas treatment, it is possible to provide an exhaust gas treatment method excellent in maintenance cost and running cost.

[Structure of exhaust gas treatment system]
Next, the configuration of the exhaust gas treatment system according to the second embodiment will be described with reference to FIG. The exhaust gas treatment system includes a waste incinerator 10, a gas cooling device 20, a dust collector 30 such as a bag filter, a chemical supply device 40, an attracting ventilator 50, a chimney 60, and a control device 70.

The waste incinerator 10 incinerates municipal waste, industrial waste, and the like using combustion air supplied by a primary combustion air supply means (not shown), and the type thereof does not matter.

Further, the waste incinerator 10 according to the present embodiment is provided with a heat recovery means 11 for recovering heat generated by incineration. In the present embodiment, the heat recovery means 11 is composed of an air-cooled jacket 11a that covers the periphery of the waste incinerator 10 and a furnace body cooling blower 11b that supplies air to the air-cooled jacket 11a, but the present invention is limited to this. There are various heat recovery means that recover heat and generate high-temperature fluid, such as those that recover heat by steam or water, and those that recover heat by heat transfer tubes arranged in the furnace. Used.

The gas cooling device 20 can supply the temperature of the exhaust gas discharged from the waste incinerator 10 to the dust collector 30 such as a bag filter, and is described in the "Guidelines for Prevention of Dioxins Generation Related to Waste Disposal". The temperature is lowered to about 200 ° C. or lower, and the type does not matter.

The dust collector 30 neutralizes or adsorbs and removes impurities such as dust and harmful components contained in the exhaust gas by filtering the exhaust gas whose temperature has been reduced by the gas cooling device 20. Does not matter.

In the present embodiment, as the dust collector 30, a bug filter provided with a filter cloth (not shown) for filtering dust and harmful components is used.

A chemical supply device 40 is provided on the upstream side of the dust collector 30, and is contained in the exhaust gas and the alkaline chemical for neutralizing acidic components such as hydrogen chloride and sulfur oxides contained in the exhaust gas. An adsorbent such as activated carbon for adsorbing harmful substances is supplied to the exhaust gas and the dust collector 30.

The attraction ventilator 50 is a ventilator arranged downstream of the dust collector 30, and is for sucking the exhaust gas purified by the dust collector 30 and releasing the exhaust gas from the chimney 60 to the atmosphere. ..

The chimney 60 discharges the exhaust gas discharged from the waste incinerator 10 into the atmosphere, and is arranged downstream of the induction ventilator 50.

The control device 90 produces a chemical and supplies the chemical to the flue gas stack depending on the situation.

[Structure of drug supply device 40]
The chemical supply device 40 according to the present embodiment uses the heat recovered from the waste incinerator 10 to generate porous sodium carbonate and supplies it into the exhaust gas from the exhaust gas stack, and is a sodium carbonate generation tank. It is composed of 41, a crude sodium carbonate supply device 42, a vacuum exhaust device 43, a heating device 44, and a discharge device 45.

The sodium carbonate generation tank 41 is composed of a container having a structure capable of withstanding a vacuum state of 10 Pa to 5 kPa and a temperature of 150 to 200 ° C., a crude baking soda supply device 42 for supplying crude baking soda upward, and a crude sodium carbonate supply device 42 below. A discharge device 45 for discharging the generated porous sodium carbonate is connected. The sodium carbonate generation tank 41 temporarily stores the crude baking soda supplied by the crude baking soda supply device 42, and discharges the generated porous sodium carbonate by the discharge device 45.

The crude baking soda supply device 42 comprises well-known supply means such as a conveyor and a chute (not shown), and causes clogging or aggregation of crude baking soda having an average particle size of 70 to 200 μm carried into a waste treatment facility by, for example, a lorry or the like. It can be smoothly supplied to the sodium carbonate generation tank 41 without any problem.

The vacuum exhaust device 43 is composed of well-known exhaust means such as a vacuum pump and an exhaust blower, and has a function of holding the inside of the sodium carbonate generation tank 41 in a vacuum state of 10 Pa to 5 kPa. The gas in the sodium carbonate generation tank 41 exhausted by the vacuum exhaust device 43 may be supplied to the dust collector 30 to be purified and then released to the atmosphere together with the exhaust gas.

The heating device 44 is composed of a heat transfer tube inserted into the sodium carbonate generation tank 41, and uses the heat of the waste incinerator 10 recovered by the heat recovery means 11 to move 150 to 150 in the sodium carbonate generation tank 1. It has a function of uniformly heating to 200 ° C.

In the present embodiment, the air heated by flowing through the air-cooled jacket 11a constituting the heat recovery means 11 flows through the heat transfer tube constituting the heating device 44, thereby passing through the sodium carbonate generation tank 1. Heat to 150-200 ° C.

The heating device 44 is not limited to the heat transfer tube inserted into the sodium carbonate generation tank 41, and may be configured by a jacket covering the sodium carbonate generation tank 41.

The discharge device 45 includes a discharge conveyor 45a connected to the lower end of the sodium carbonate generation tank 41, a sodium carbonate storage tank 45b for temporarily storing the generated porous sodium carbonate, and a porous sodium carbonate storage tank. It is composed of a chemical supply blower 45c or the like that cuts out sodium carbonate as needed and supplies it to the flue at the entrance of the dust collector, and clogs or aggregates the porous sodium carbonate generated in the sodium carbonate generation tank 41. It can be smoothly discharged from the sodium carbonate generation tank 41 and supplied into the exhaust gas without causing it to occur.

[Exhaust gas treatment procedure]
Next, the procedure for exhaust gas treatment using the exhaust gas treatment system according to the present embodiment will be described with reference to the flowchart shown in FIG.

[Step S200: Heat recovery]
First, during the operation of the waste incinerator 10, the heat generated by the incineration of the waste is recovered by the heat recovery means 11 (step S200).

In the present embodiment, the heat recovery means 11 is composed of an air-cooled jacket 11a that covers the periphery of the furnace body of the waste incinerator 10 and a furnace body cooling blower 11b that supplies air to the air-cooled jacket 11a. Therefore, step S200. High-temperature air is generated as the heat is recovered, but when the high-temperature air is not supplied to the sodium carbonate generation tank 41, it may be supplied as combustion air into the waste incinerator 10 through a branch path (not shown).

[Step S210: Storage of crude baking soda]
In producing porous sodium carbonate in the exhaust gas treatment system according to the present embodiment, first, the crude baking soda supply device 42 of the chemical supply device 40 is started, and the average particle size is 70 in the sodium carbonate generation tank 41. A crude baking soda of ~ 200 μm is supplied (step S210). The crude baking soda supply device 42 brings the crude baking soda carried into the waste treatment facility by a lorry or the like into the sodium carbonate generation tank 41 installed in the waste treatment facility by using means such as a conveyor or a chute (not shown). It is what we supply.

At this time, the discharge device 45 is not activated, and the crude baking soda can be temporarily stored in the sodium carbonate generation tank 41.

At that time, since the average particle size of the crude baking soda is about 70 to 200 μm, unlike the finely pulverized baking soda, the crude baking soda has good fluidity and is smoothly supplied without causing a bridge in the sodium carbonate generation tank 41. be able to.

[Step S220: Vacuum exhaust in the sodium carbonate generation tank]
When the crude baking soda is supplied in step S210, the vacuum exhaust device 43 is then activated to exhaust the inside of the sodium carbonate generation tank 41 filled with the crude baking soda so as to be in a vacuum state of 10 Pa to 5 kPa (step S220). ).

At this time, since the crude baking soda in the sodium carbonate generation tank 41 has an average particle size of about 70 to 200 μm, it is not sucked into the vacuum exhaust device 43, that is, without causing clogging of the vacuum exhaust device 43. The inside of the sodium carbonate generation tank 41 can be evacuated to a vacuum.

The gas in the sodium carbonate generation tank 41 exhausted by the vacuum exhaust device 43 may be supplied to the dust collector 30 to be purified and then released to the atmosphere together with the exhaust gas.

[Step S230: Heating in the sodium carbonate generation tank]
When the vacuum exhaust in the sodium carbonate generation tank 41 is completed in step S220, the heating device 44 is then activated, and the crude baking soda is heated to 150 to 200 ° C. using the heat recovered by the heat recovery means 11. Step S230).

The heating device 44 according to the present embodiment is composed of a heat transfer tube through which high-temperature air heated by the air-cooled jacket 11a constituting the heat recovery means 11 flows, and in step S230, the combustion air supply means and the like until then. The high temperature air supplied to the heating device 44 is operated so as to be supplied to the heat transfer tube constituting the heating device 44. In this way, in step S230, the inside of the sodium carbonate generation tank 1 is heated to 150 to 200 ° C. by utilizing the heat generated in the waste incinerator 10.

At this time, in the sodium carbonate generation tank 41, the reaction of the above formula (1) occurs by heating crude baking soda having an average particle size of 70 to 200 μm to 150 to 200 ° C. under a vacuum of 10 Pa to 5 kPa, and NaHCO3 H ₂ O and CO ₂ are released from the represented baking soda to produce porous sodium carbonate.

[Step S240: Supply of sodium carbonate into the exhaust gas]
In step S230, when the porous sodium carbonate is generated, the heating device 44 and the vacuum exhaust device 43 are stopped, the discharge device 45 is started, and the sodium carbonate generated from the sodium carbonate generation tank 41 is discharged. It is supplied into the exhaust gas (step S240).

That is, the discharge conveyor 45a connected to the lower end of the sodium carbonate generation tank 41 is started, sodium carbonate is cut out from the sodium carbonate generation tank 41 and temporarily stored in the sodium carbonate storage tank 45b, and the stored sodium carbonate is stored. A chemical supply blower 45c is used to supply the dust collector inlet flue as needed.

At this time, since the produced sodium carbonate has an average particle size of 70 to 200 μm, it can be smoothly discharged from the sodium carbonate generation tank 41 without causing a bridging phenomenon or discharge failure.

The porous sodium carbonate blown into the exhaust gas from the dust collector inlet flue in this way causes the reaction of the above formulas (2) and (3) with the acidic substance in the exhaust gas.

That is, when sodium carbonate reacts with hydrogen chloride, hydrogen chloride is neutralized, sodium chloride, water and carbon dioxide are generated, and sodium carbonate reacts with sulfur dioxide and oxygen to neutralize sulfur dioxide. , Sodium sulfate and carbon dioxide are produced.

Then, as shown in Table 1, the porous sodium carbonate produced by the production procedure according to the present embodiment has a specific surface area that is twice or more twice as much as that in the case where crude baking soda is simply heated under atmospheric pressure. Since it has the above total pore volume, it has a much higher removal efficiency. In addition, the specific surface area and the total pore volume are both larger than those of finely pulverized baking soda heated under atmospheric pressure, and the removal efficiency can be higher than that of finely pulverized baking soda. Further, unlike the finely pulverized one, since the average particle size is 70 to 200 μm, there are no problems such as bridging in the storage tank and poor discharge, and no device for pulverization is required. By following the treatment procedure according to the above, it is possible to provide an exhaust gas treatment method excellent in maintenance cost and running cost.

As described above, by applying the exhaust gas treatment procedure according to the present embodiment, it is possible to efficiently remove the acidic component without using a separate device such as a pulverizer, and moreover, the chemical can be used. It is possible to provide an exhaust gas treatment method that is easy to handle and can save maintenance costs. Moreover, since the heat generated in the waste incinerator 10 is recovered and used, no separate heating means is required, and it can be easily applied to the existing waste treatment equipment.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments described above. In addition, the effects described in the embodiments of the present invention merely list the most preferable effects arising from the present invention, and the effects according to the present invention are limited to those described in the embodiments of the present invention. is not.

Further, the above-described embodiment has been described in detail in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to the one including all the described configurations.

The exhaust gas treatment chemical manufacturing method, the exhaust gas treatment method and the exhaust gas treatment system of the present invention can be applied to various types of waste incineration facilities that treat various types of waste.

1 Sodium carbonate generation tank 2 Coarse baking soda supply device 3 Vacuum exhaust device 4 Heating device 5 Discharge device 10 Waste incinerator 11 Heat recovery means 11a Air cooling jacket 11b Blower for cooling the furnace body 20 Gas cooling device 30 Dust collector 40 Chemical supply device 41 Sodium carbonate generation tank 42 Crude baking soda supply device 43 Vacuum exhaust device 44 Heating device 45 Discharge device 45a Conveyor 45b Sodium carbonate storage tank 45c Chemical supply blower 50 Induction blower 60 Chimney

Claims (4)

An exhaust gas treatment chemical manufacturing method that produces porous sodium carbonate from baking soda.
A method for producing an exhaust gas treatment chemical, which comprises a step of heating crude baking soda having an average particle size of 70 to 200 μm under a vacuum of 10 Pa to 5 kPa at 150 to 200 ° C. The porous sodium carbonate produced by the method for producing an exhaust gas treatment chemical according to claim 1 is used.
Has a step to blow into the exhaust gas generated by waste incineration,
Exhaust gas treatment method. This is an exhaust gas treatment method for treating the exhaust gas discharged from the waste incinerator in a waste incineration facility having a waste incinerator that incinerates waste and a chemical generation tank that generates chemicals to be blown into the exhaust gas.
A step of storing crude baking soda having an average particle size of 70 to 200 μm in the drug generation tank.
Steps to recover the heat of the waste incinerator,
A step of vacuum exhausting so that the pressure in the chemical generation tank becomes 10 Pa to 5 kPa.
By supplying the heat recovered from the waste incinerator to the chemical generation tank, the crude baking soda is heated at 150 to 200 ° C. in the chemical generation tank held in a vacuum to generate porous sodium carbonate. Step,
With the step of blowing the generated porous sodium carbonate into the exhaust gas,
Exhaust gas treatment method. An exhaust gas treatment system that treats the exhaust gas discharged from the waste incinerator in a waste incineration facility having a waste incinerator that incinerates waste and a chemical generation tank that generates chemicals to be blown into the exhaust gas.
A storage means for storing crude baking soda having an average particle size of 70 to 200 μm in the drug generation tank.
A heat recovery means for recovering heat from the waste incinerator,
A vacuum exhaust means for vacuum exhaust so that the pressure in the chemical generation tank is 10 Pa to 5 kPa.
A heating means for heating the crude baking soda to 150 to 200 ° C. in the drug generation tank held in a vacuum by supplying the heat recovered by the heat recovery means to the drug generation tank.
A blowing means for blowing porous sodium carbonate produced in the chemical generation tank into the exhaust gas.
Has an exhaust gas treatment system.