JP4355817B2 - High temperature exhaust gas purification treatment agent and high temperature exhaust gas purification treatment method using the same - Google Patents

Description

  The present invention relates to a purification treatment agent for high-temperature exhaust gas for purifying high-temperature exhaust gas generated from an incinerator that incinerates waste, municipal waste, and the like, and a high-temperature exhaust gas purification treatment method using the same.

  Conventionally, in the high temperature gas temperature range (600-900 ° C) from the request to recover heat energy with high efficiency from the high temperature exhaust gas generated in waste incinerators, municipal waste incinerators, etc., and to suppress the generation of dioxins. Gas purification is required. The high-temperature exhaust gas contains hydrogen chloride gas (500 to 1500 ppm in a municipal waste incinerator), sulfur oxide (SOx) gas, alkali compounds, heavy metals and their compounds, and soot, and these are used in devices such as heat exchangers. On the other hand, it is known to cause intense corrosion.

As countermeasures, there are known methods that use highly corrosion-resistant materials for the equipment and methods for collecting and removing soot and dust by installing a ceramic filter in front of the equipment. Therefore, a method of reacting a corrosion-causing substance has also been proposed. For example, CaCO ₃ (calcium carbonate), CaO (quick lime), MgO (magnesia) are placed in the incinerator to neutralize acidic gases such as hydrogen chloride gas and sulfur oxide (SOx) gas, which are corrosion-causing substances. A method of adding a desalting agent such as is known (for example, see Patent Document 1). In addition, a desalting agent formed into pellets or spheres of soda lime or 3MgO ₄ SiO ₂ H ₂ O (talc) is filled into the incinerator outlet pipe, and hydrogen chloride gas in the exhaust gas at high temperature (400 to 800 ° C.) A removal method is known (see, for example, Patent Document 2). Furthermore, a method for treating acidic exhaust gas by spraying it on an exhaust gas flue using a material containing calcium oxide and silicon dioxide is also known (see, for example, Patent Document 3).
JP-A-7-83422 (Pages 2 and 3) Japanese Patent Laid-Open No. 11-276852 (pages 2 and 3) JP 2000-140565 A (2nd and 3rd pages)

  However, the above-described conventional method mainly targets acidic exhaust gas as a harmful substance contained in high-temperature exhaust gas, and is only partially purified. The high-temperature exhaust gas contains alkali compounds, heavy metals, or compounds thereof in addition to acidic gas, and it is necessary to reduce them simultaneously. However, such a purification treatment agent is not known at present.

  The present invention has been made paying attention to such problems existing in the prior art. The object of the present invention is to provide a purification treatment agent for high temperature exhaust gas capable of simultaneously reducing acid gas, alkali compound and heavy metal or its compound in the high temperature exhaust gas, and a purification treatment method for high temperature exhaust gas using the same. It is in.

In order to achieve the above object, the purification treatment agent for high-temperature exhaust gas according to the first aspect of the present invention comprises a mixed granulated product obtained by mixing and granulating lime, silica sand and kaolin, and the content of the lime. Is 70 to 45% by mass as calcium oxide, the content of silica sand is 20 to 10% by mass as silicon dioxide (excluding silicon dioxide in kaolin), and the content of kaolin is 10 to 45% by mass as kaolin. The mixed granulated product is characterized by containing 85% by mass or more of particles having a particle diameter of 45 to 300 μm .

According to a second aspect of the present invention, there is provided a method for purifying high-temperature exhaust gas, wherein the high-temperature exhaust gas is brought into contact with the high-temperature exhaust gas purification treatment agent according to claim 1 at a temperature of 600 to 900 ° C. It is characterized by collecting .

According to the present invention, the following effects can be exhibited.
According to the purification treatment agent for high-temperature exhaust gas of the invention described in claim 1, the calcium compound and silicon dioxide-containing substance in the mixed granulated product react with acidic gases such as hydrogen chloride gas and sulfur oxide gas in the high-temperature exhaust gas. To produce a stable mineral. Moreover, the clay mineral in the mixed granulated product reacts with an alkali compound and heavy metal or a compound thereof. Therefore, it is possible to simultaneously reduce the acidic gas, the alkali compound and the heavy metal or the compound thereof in the high temperature exhaust gas.

According to the high temperature exhaust gas purification treatment method of the invention described in claim 2 , in addition to the effect of the invention of claim 1, fine particles after the purification treatment can be easily removed with a ceramic filter.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings.
Purification treatment agent for high temperature exhaust gas of the present embodiment, lime, and is configured Ri by quartz sand and mixtures granules obtained by mixing granulated kaolin. Here, the high temperature in the high temperature exhaust gas means a high temperature of about 600 to 900 ° C. The harmful components in the high temperature exhaust gas include acid compounds, alkali compounds and heavy metals, or compounds thereof. Examples of the acid gas include hydrogen chloride (HCl) gas and sulfur oxide (SOx) gas. Examples of the alkali compound include potassium compounds and sodium compounds. Examples of heavy metals or compounds thereof include heavy metals such as zinc (Zn), cadmium (Cd), and lead (Pb), zinc chloride (ZnCl ₂ ), cadmium chloride (CdCl ₂ ), lead chloride (PbCl ₂ , PbCl ₄ ), and the like. Heavy metal compounds.

Lime constituting the purification treatment agent mainly reacts with acidic gas such as hydrogen chloride gas and sulfur oxide gas (SOx gas) in the high temperature exhaust gas to generate a stable mineral. Specific examples of the lime, quicklime, anti-stone ash is used.

Silica sand , like lime , reacts mainly with hydrogen chloride gas and sulfur oxide gas in high-temperature exhaust gas to produce stable minerals. Silicofluoride sand are specifically used as silica sand.

Kaolin is for reacting mainly with alkali compounds and heavy metals or their compounds in high-temperature exhaust gas to collect these components and prevent fusion to other substances. Kaolin is a layered silicate having a layered structure. Specifically as kaolin kaolin minerals it is used.

Mixture granulated product, lime is a mixture of three parties silica sand and kaolin obtained by the granulation (shaping into granules) to Turkey. Granulation is performed by a method of adding water or an organic solvent to the raw material and spray-drying with a spray dryer as a slurry, or a method of drying after granulation with a stirring granulator. The particle size of the mixed granulated product is set to such a particle size that it is easy to capture harmful substances in the high temperature exhaust gas, and the ceramic filter is less clogged and adhered. Specifically, those containing 85% by mass or more of particles having a particle diameter of 45 to 300 μm are preferable.

Composition of the mixed granules is 70 to 45 mass% lime as CaO, silica sand 20 to 10 wt% as SiO ₂ (except for SiO ₂ in kaolin), Ru 10 to 45% by mass kaolin as kaolin . This composition, 60 to 45 mass% lime as CaO, silica sand 15 to 10% by mass as SiO _2, and still more preferably kaolin is 25 to 45 mass% of kaolin.

As a mixed granulated product, a mixture of lime , quartz sand and kaolin and granulated is more preferable than a mixture of lime and quartz sand and granulated with kaolin . This is because the three components are almost uniformly contained in the particles constituting the mixed granulated product, and all the particles can contact the high-temperature exhaust gas and contribute to the purification treatment.

  The ceramic filter is for removing fine particles after being purified by the mixed granulated product. This ceramic filter is made of a sintered body such as cordierite, silicon carbide, alumina, mullite, or an oxide or silicon carbide composite material such as aluminosilicate using oxide fibers as reinforcing fibers. Among these, those formed of cordierite or mullite are preferable from the viewpoint of impact resistance, heat resistance, and corrosion resistance.

  Examples of the structure of the ceramic filter include a tube type, a candle type, and a honeycomb type. Use a honeycomb ceramic filter with a large filtration area per unit volume because the apparent processing gas volume is higher in the high temperature range than in the low temperature range, and the ceramic filter used must be compact. Is desirable. In this case, a sufficient backwashing property is obtained because the viscosity of the collected fine particles (dust, ash) is increased in a high temperature range, and the opening of 2.5 mm is less likely to cause clogging of the honeycomb flow path. As described above, it is more desirable to use a honeycomb type ceramic filter of 4 mm or more.

Next, a system for purifying high-temperature exhaust gas using the above mixed granulated product will be described.
As shown in FIG. 1, one end of an exhaust gas duct 3 is connected to an outlet 2 of an incinerator 1 for incinerating waste, municipal waste, etc., and the other end is connected to a dust collector 4 having a substantially cylindrical shape. Yes. A high temperature exhaust gas of 600 to 900 ° C. generated in the incinerator 1 is introduced into the dust collector 4 through the exhaust gas duct 3. Inserted into the exhaust gas duct 3 is a tip of a purification treatment agent supply pipe 6 for supplying the purification treatment agent 5 made of the mixed granulated material together with air. The insertion portion 6a at the tip of the purification treatment agent supply pipe 6 is bent in the direction in which the high-temperature exhaust gas flows at substantially the center position of the exhaust gas duct 3 so that the purification treatment agent 5 is supplied smoothly. An air compressor 7 is provided on the proximal end side of the purification treatment agent supply pipe 6, and compressed air is supplied from the purification treatment agent supply pipe 6 to the exhaust gas duct 3.

  The lower part of the purification treatment agent hopper 8 in which the purification treatment agent 5 is accommodated is formed in a tapered shape with a diameter decreasing toward the bottom, and the lower end thereof is used to stably supply the purification treatment agent 5 as a quantitative supply device. A screw feeder 9 is provided. The purification treatment agent supply pipe 6 at a position below the screw feeder 9 is provided with an ejector 10, and the purification treatment agent 5 supplied from the screw feeder 9 is sucked by the air passing through the ejector 10 to be purified treatment supply pipe 6. It is transported and fed in. As described above, the purification treatment agent 5 rides on the flow of air and is introduced into the exhaust gas duct 3 from the insertion portion 6a through the purification treatment agent supply pipe 6, and hydrogen chloride gas in the high temperature exhaust gas in the air stream, Sulfur oxide gas, alkali compounds and heavy metals or their compounds react with the purification treatment agent 5.

  A honeycomb-type ceramic filter 11 is disposed in the upper part of the dust collecting device 4 so as to collect the fine particles after the purification treatment. Connected to the upper end of the dust collector 4 is an exhaust pipe 14 for releasing the gas after the fine particles are collected by the ceramic filter 11. The lower part of the dust collector 4 is formed in a taper shape with a diameter decreasing toward the bottom, and a lead-out pipe 12 for discharging fine particles accumulated in the dust collector 4 is connected to the bottom. The outlet pipe 12 is provided with a valve 13 for opening and closing the pipe line, and the lower end of the outlet pipe 12 is connected to a dust hopper 15 for collecting fine particles.

  Now, when the high temperature exhaust gas discharged from the incinerator 1 is purified with the purification treatment agent 5 made of the mixed granulated material, the high temperature exhaust gas is introduced into the exhaust gas duct 3 connected to the discharge port 2 of the incinerator 1. To do. On the other hand, the purification agent 5 sucked into the purification agent supply pipe 6 from the purification agent hopper 8 by the ejector 10 is discharged into the exhaust gas duct 3 into the exhaust gas duct 3. In the exhaust gas duct 3, the mixed granulated product of the purification treatment agent 5 comes into contact with harmful substances while being stirred in the stream of high-temperature exhaust gas maintained at 600 to 900 ° C. At this time, hydrogen chloride gas, sulfur oxide gas, alkali compound and heavy metal in the high-temperature exhaust gas or their compounds react with the purification treatment agent 5 based on the following reaction formulas (1), (2) and (3). .

3CaO + SiO ₂ + 2HCl → Ca ₃ SiO ₄ Cl ₂ + H ₂ O (1)
_{10CaO + 3SiO 2 + 2HCl + 3SO} 2 + 3 / 2O 2 →
Ca ₁₀ (SiO ₄ ) ₃ (SO ₄ ) ₃ Cl ₂ + H ₂ O (2)
2NaCl + Al ₂ O ₃ 2SiO ₂ + H ₂ O →
_{Na 2 OAl 2 O 3 2SiO 2} + 2HCl ··· (3)
That is, according to the reaction formula (1), hydrogen chloride (HCl) gas in the high temperature exhaust gas reacts with lime and silica sand in the mixed granulated product to generate a stable mineral (Ca ₃ SiO ₄ Cl ₂ ). Further, according to the reaction formula (2), hydrogen chloride gas and sulfur oxide (SOx) gas react with lime and silica sand in the mixed granulated product to generate a stable mineral. Furthermore, sodium chloride (NaCl) reacts with kaolin in the mixed granulated product and is captured by the reaction formula (3), thereby preventing the sodium chloride from fusing to the surface of the ceramic filter 11. Cadmium chloride (CdCl ₂ ) and lead chloride (PbCl ₂ , PbCl ₄ ) react and are trapped in the same manner as sodium chloride.

  Thereafter, the purified gas enters the dust collector 4 and passes through the honeycomb-type ceramic filter 11 located from the lower part to the upper part. At this time, fine particles (dust) made of mineral or the like as a reaction product contained in the purified gas are collected and removed. The fine particles are adsorbed by the mixed granulated material, and can be easily peeled off from the ceramic filter 11 to prevent clogging and adhesion. Further, in the ceramic filter 11, unreacted components in the high temperature exhaust gas react with the mixed granulated material held on the ceramic filter 11 based on the reaction formulas (1) to (3) and are purified. The fine particles collected by the ceramic filter 11 are peeled off from the filter wall by high-pressure air and dropped. The fine particles can be accommodated in the dust hopper 15 by opening the valve 13. On the other hand, the gas that has passed through the ceramic filter 11 is sent from the exhaust pipe 14 to a heat exchanger (not shown) where the high-temperature purified gas is cooled.

The effects exhibited by the embodiment described in detail above will be collectively described below.
· Purification treatment agent 5 for high temperature exhaust gas of the present embodiment, lime, and is configured Ri by mixing granules obtained by mixing granulated silica sand and kaolin. For this reason, lime and silica sand in the mixed granulated product react with acidic gases such as hydrogen chloride gas and sulfur dioxide gas in the high-temperature exhaust gas to generate stable minerals. Further, kaolin in the mixed granulated product reacts with an alkali compound and heavy metal or a compound thereof. Therefore, it is possible to simultaneously reduce the acidic gas, the alkali compound and the heavy metal or the compound thereof in the high temperature exhaust gas.

  -In the purification processing agent 5, what has a particle diameter of 45-300 micrometers as a mixed granulated material is contained 85 mass% or more, and the particle size distribution is in a certain range. For this reason, the purification treatment effect by the purification agent 5 can be improved.

- content of lime mixture granulated product in the 70 to 45 mass% of calcium oxide, the content of silica sand content of 20 to 10 wt% and kaolin as silicon dioxide is set to 10 to 45 mass% of kaolin ing. For this reason, the purification treatment effect by the purification agent 5 can be improved.

The high temperature exhaust gas purification treatment method of the present embodiment uses the above-described high temperature exhaust gas purification treatment agent 5, contacts the high temperature exhaust gas with the purification treatment agent 5 at a temperature of 600 to 900 ° C., and then the inside of the dust collector 4. The ceramic filter 11 collects fine particles. For this reason, it is possible to simultaneously reduce the acidic gas, alkali compound and heavy metal or compound thereof in the high-temperature exhaust gas by the purification treatment agent 5, and it is possible to easily remove the fine particles after the purification treatment with the ceramic filter 11.
(Second Embodiment)
Next, a second embodiment of the present invention will be described in detail based on the drawings. In the second embodiment, differences from the first embodiment will be mainly described.

As shown in FIG. 2, one end of an exhaust gas duct 3 is connected to the discharge port 2 provided at the top of the incinerator 1, and the other end is connected to a reaction tube 22 via a flow meter 20 and a pressure gauge 21. Yes.
A support shelf 23 is provided at a lower position in the reaction tube 22, a ceramic filter 11 is disposed on the support shelf 23, and a purification treatment agent 5 made of the mixed granulated material is further supported on the support shelf 23. It can be passed. Then, the high-temperature exhaust gas passing from above to below contacts with the purification treatment agent 5 and is purified, and the generated fine particles (dust) are collected by the ceramic filter 11. A heating device 24 is disposed around the reaction tube 22 so that the reaction tube 22 is heated and held at 600 to 900 ° C. The outlet tube 12 is connected to the bottom of the reaction tube 22 and the purified gas is discharged.

  When the high temperature exhaust gas discharged from the incinerator 1 is purified with the purification treatment agent 5 made of the mixed granulated material, the high temperature exhaust gas is flowed from the exhaust gas duct 3 connected to the discharge port 2 of the incinerator 1. It introduces into the reaction tube 22 through the meter 20 and the pressure gauge 21. The hot gas introduced into the reaction tube 22 passes through the purification treatment agent 5 made of the mixed granulated material while being kept at 600 to 900 ° C. by the heating device 24. At this time, hydrogen chloride gas, sulfur oxide gas, alkali compound and heavy metal or compound thereof in the high temperature exhaust gas are based on the purification treatment agent 5 and the reaction formulas (1), (2) and (3) described in the first embodiment. React.

  Thereafter, the purified gas passes through the ceramic filter 11. At this time, fine particles made of mineral or the like as a reaction product contained in the purified gas are collected and removed. The fine particles are adsorbed by the mixed granulated material, and are easily peeled off from the ceramic filter 11, and clogging and adhesion are suppressed. The high-temperature purified gas that has passed through the ceramic filter 11 is discharged from the outlet tube 12, sent to a heat exchanger (not shown), and cooled there.

It should be noted that both the above embodiments can be modified and embodied as follows.
When the high-temperature exhaust gas contains a large amount of acidic gas such as hydrogen chloride gas or sulfur dioxide gas, the lime content in the purification treatment agent 5 is 70% by mass or more as calcium oxide, and the silica sand content is 20 as silicon dioxide. It can also be made into mass% or more. On the other hand, when there are many heavy metal compounds such as zinc chloride in the high-temperature exhaust gas, the kaolin content can be 45% by mass or more as kaolin.

  -By increasing the opening of the ceramic filter 11, the content of the mixed granulated product having a particle size of 45 to 300 [mu] m is less than 85% by mass and having a particle size of less than 45 [mu] m.

  -In 1st Embodiment, when the incinerator 1 is a fluidized bed or a circulating fluidized bed, the insertion part 6a of the purification treatment agent supply pipe 6 is inserted in the incineration furnace 1, and the purification treatment agent is in the incineration furnace 1. It is also possible to carry out purification treatment by reacting the mixed granulated product 5 with harmful substances in the high temperature exhaust gas.

  -In 2nd Embodiment, the purification processing agent 5 and the ceramic filter 11 can also be arrange | positioned in the position spaced apart.

Examples and comparative examples will be given below to describe the embodiment more specifically.
(Examples 1 to 3 and Comparative Examples 1 and 2)
As the purification treatment agent 5 of Examples 1 to 3, a mixed granulated product obtained by mixing and granulating lime , silica sand and kaolin was used. That is, (45-57 wt% as CaO) slaked lime as lime, 10 to 45 mass as silica sand (as SiO ₂ 10 to 45% by weight) and kaolin as silica sand Georgia Kaolin (Kaolin was produced in the United States of Georgia, as kaolin %) Was used, and a mixed granulated product obtained by mixing these substances and granulating them with a spray dryer was used. The particle size of the mixed granulated product was adjusted so that the particle size of 45 to 300 μm was 85% by mass or more. As the ceramic filter 11, a honeycomb type ceramic filter having a mesh opening (opening pitch of honeycomb cells) of 4.0 mm was used.

In Comparative Example 1, using purification treatment agent consisting of the granulated product of quartz sand and as silica sand (79 wt% as CaO) slaked lime as lime (21% by mass as SiO _2). In Comparative Example 2, using purification treatment agent consisting of granulated product only Georgia Kaolin as kaolin.

Using this purification treatment agent 5, a high-temperature exhaust gas containing 1000 ppm of hydrogen chloride (HCl) gas, 200 ppm of sulfur dioxide (SO ₂ ) gas and 1000 ppm of zinc chloride (ZnCl ₂ ) in the purification treatment system shown in FIG. The purification treatment was performed at ° C. The removal rate (%) of hydrogen chloride gas, sulfur dioxide gas and zinc chloride after the purification treatment and clogging of the ceramic filter 11 were examined, and the results are shown in Table 1.

  In Table 1, the removal rate of hydrogen chloride gas and sulfur dioxide represents 1- (initial concentration−concentration after 30 minutes) / (initial concentration). Moreover, the removal rate of zinc chloride represents (the amount of zinc contained in the purification agent after 30 minutes) / (the initial amount of zinc).

表１に示したように、実施例１〜３では塩化水素ガスの除去率８７％以上、二酸化硫黄ガスの除去率１００％及び塩化亜鉛の除去率５９％以上を達成することができた。更に、セラミックフィルター１１の目詰まりも認められなかった。これに対し、消石灰と珪砂との造粒物よりなる浄化処理剤を用いた場合（比較例１）には、塩化水素ガス及び二酸化硫黄ガスの除去率は良好であったが、塩化亜鉛の除去率が１７．３％という低い結果であった。更に、ジョージアカオリンの造粒物よりなる浄化処理剤を用いた場合（比較例２）には、塩化亜鉛の除去率は良好であったが、塩化水素ガス及び二酸化硫黄ガスの除去率は低いものであった。

As shown in Table 1, in Examples 1 to 3, it was possible to achieve a hydrogen chloride gas removal rate of 87% or more, a sulfur dioxide gas removal rate of 100%, and a zinc chloride removal rate of 59% or more. Furthermore, clogging of the ceramic filter 11 was not recognized. On the other hand, when the purification agent comprising a granulated product of slaked lime and silica sand was used (Comparative Example 1), the removal rate of hydrogen chloride gas and sulfur dioxide gas was good, but the removal of zinc chloride The rate was as low as 17.3%. Furthermore, when the purification agent comprising the granulated product of Georgia Kaolin was used (Comparative Example 2), the removal rate of zinc chloride was good, but the removal rate of hydrogen chloride gas and sulfur dioxide gas was low. Met.

  In addition, in order to simultaneously purify alkaline compounds (potassium chloride and sodium chloride), the combustion gas after burning woody biomass (combustion gas when burning cedar trees) is added to the above high-temperature exhaust gas, and potassium and sodium are added. The removal rate (%) and clogging of the ceramic filter 11 were examined, and the results are shown in Table 2.

表２に示したように、実施例１及び３では、カリウムの除去率が６０％以上及びナトリウムの除去率が９１％以上であり、良好であった。これに対し、比較例１ではカリウムの除去率が３５％及びナトリウムの除去率が７４％という低い結果であった。
（実施例４、５及び比較例３）
また、実施例４では実施例１と同じ浄化処理剤５、実施例５では実施例３と同じ浄化処理剤５及び比較例３では比較例１と同じ浄化処理剤を用いた。そして、アルカリ化合物（塩化カリウム及び塩化ナトリウム）の浄化処理試験について図２の浄化処理システムを用い、６００℃で実施した。木質バイオマス燃焼後の燃焼ガスを用い、カリウム及びナトリウムの除去率（％）とセラミックフィルターの目詰まりを調べ、それらの結果を表３に示した。

As shown in Table 2, in Examples 1 and 3, the removal rate of potassium was 60% or more and the removal rate of sodium was 91% or more, which was good. On the other hand, in Comparative Example 1, the potassium removal rate was 35% and the sodium removal rate was 74%.
(Examples 4 and 5 and Comparative Example 3)
In Example 4, the same purification treatment agent 5 as in Example 1 was used, in Example 5, the same purification treatment agent 5 as in Example 3, and in Comparative Example 3, the same purification treatment agent as in Comparative Example 1 was used. Then, a purification treatment test for alkaline compounds (potassium chloride and sodium chloride) was performed at 600 ° C. using the purification treatment system of FIG. Using the combustion gas after burning woody biomass, the removal rate (%) of potassium and sodium and clogging of the ceramic filter were examined, and the results are shown in Table 3.

表３に示したように、実施例４及び５では、カリウムの除去率が６２％以上及びナトリウムの除去率が９３％以上であり、良好であった。これに対し、比較例３ではカリウムの除去率が３９％及びナトリウムの除去率が７１％という低い結果であった。

As shown in Table 3, in Examples 4 and 5, the removal rate of potassium was 62% or more and the removal rate of sodium was 93% or more, which was good. In contrast, in Comparative Example 3, the potassium removal rate was 39% and the sodium removal rate was 71% .

( Examples 6 and 7 )
Purifying treatment was performed in the same manner as in Example 1 except that the ratio of the mixed granulated product having a particle size of 45 to 300 μm was changed. The removal rate (%) of hydrogen chloride gas, sulfur dioxide gas and zinc chloride and clogging of the ceramic filter 11 were examined, and the results are shown in Table 4 .

表４に示したように、実施例６及び７では塩化水素ガスの除去率９２％以上、二酸化硫黄ガスの除去率８５％以上及び塩化亜鉛の除去率６０％以上を達成することができた。また、実施例７ではセラミックフィルター１１の目詰まりは認められなかったが、実施例６では混合造粒物の粒度として４５μｍ未満の割合が４０質量％と大きいことから、セラミックフィルター１１の目詰まりが認められた。

As shown in Table 4 , in Examples 6 and 7 , it was possible to achieve a hydrogen chloride gas removal rate of 92% or more, a sulfur dioxide gas removal rate of 85% or more, and a zinc chloride removal rate of 60% or more. Moreover, although clogging of the ceramic filter 11 was not recognized in Example 7 , since the ratio of less than 45 μm is large as 40% by mass as the particle size of the mixed granulated product in Example 6 , clogging of the ceramic filter 11 was observed. Admitted.

Next, the technical idea that can be grasped from the embodiment will be described below .

- the content of the lime 60-45% by weight as calcium oxide, the content of silica sand content of 15 to 10 wt% and kaolin as silicon dioxide according to claim 1 which is 25 to 45 mass% of kaolin Purification agent for high temperature exhaust gas. When comprised in this way, the purification process effect by a purification processing agent can be improved further.

The method for purifying high-temperature exhaust gas according to claim 2 , wherein the purification treatment is performed while flowing a purification treatment agent in the air flow of the high-temperature exhaust gas. According to this purification treatment method, the high temperature of the exhaust gas discharged from an incinerator or the like can be used, and the contact time between the harmful substance in the high temperature exhaust gas and the purification treatment agent can be lengthened to improve the purification treatment efficiency. .

Schematic explanatory drawing which shows the system for purifying the high temperature exhaust gas from the incinerator in 1st Embodiment. Schematic explanatory drawing which shows the system for purifying the high temperature exhaust gas from the incinerator in 2nd Embodiment.

Explanation of symbols

  5 ... Purification agent, 11 ... Ceramic filter.

Claims (2)

Excluding lime, Ri silica sand and Rina by mixing granules kaolin by mixing granulating, 70-45 wt% as the calcium oxide content of the lime content of silica sand silicon dioxide in silicon dioxide (kaolin ) 20 to 10% by mass and the content of kaolin is 10 to 45% by mass as kaolin, and the mixed granulated product contains 85% by mass or more having a particle diameter of 45 to 300 μm. A cleansing agent for high temperature exhaust gas . A method for purifying high-temperature exhaust gas, comprising: bringing the high-temperature exhaust gas into contact with the purification treatment agent for high-temperature exhaust gas according to claim 1 at a temperature of 600 to 900 ° C, and collecting fine particles with a ceramic filter.

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