JPH11253722A - Ceramic filter - Google Patents
Ceramic filterInfo
- Publication number
- JPH11253722A JPH11253722A JP5929098A JP5929098A JPH11253722A JP H11253722 A JPH11253722 A JP H11253722A JP 5929098 A JP5929098 A JP 5929098A JP 5929098 A JP5929098 A JP 5929098A JP H11253722 A JPH11253722 A JP H11253722A
- Authority
- JP
- Japan
- Prior art keywords
- ceramic filter
- filter
- ceramic
- aggregate particles
- particle size
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Filtering Materials (AREA)
- Porous Artificial Stone Or Porous Ceramic Products (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】 本発明は、燃焼排ガス等
の、高温で燃えかすや煤を含んだ排ガスを浄化するため
のセラミックフィルターに関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceramic filter for purifying exhaust gas such as combustion exhaust gas, which contains high-temperature combustors and soot.
【０００２】[0002]
【従来の技術】 火力発電所や工場のボイラー、焼却炉
などからの高温排ガス中には、未燃焼カーボンや熱分解
ガスの可燃性物質、あるいはフライアッシュ等煤塵類の
不燃性物質が多量に含まれている。これらの物質は、こ
のまま大気中に放出することは環境衛生上大きな問題で
あり、浄化処理する必要があり、通常、可燃性物質の再
燃焼処理とその後工程での除塵処理が行われる。2. Description of the Related Art High-temperature exhaust gases from boilers, incinerators, and the like in thermal power plants and factories contain large amounts of combustible substances such as unburned carbon and pyrolysis gas, and non-flammable substances such as fly ash and dust. Have been. It is a great problem in terms of environmental sanitation to release these substances into the atmosphere as they are, and it is necessary to carry out a purification treatment. Usually, a reburning treatment of a combustible substance and a dust removal treatment in a subsequent step are performed.
【０００３】 従来、燃焼排ガスからの除塵方法として
は、電気集塵機やバグフィルターが知られているが、高
温の燃焼排ガスをそのまま用いることはできず所定温度
まで冷却する必要があった。また、膜や不織布（フェル
ト）の場合には、目が細かく薄いために煤塵類の捕集性
能は高いものの早期に目詰まりし易く、高温のガスには
使用できないという問題がある。セラミックフォーム
は、気孔率が高いために、通気抵抗は小さいものの、一
旦捕集した煤塵類を流出させ易いという問題がある。Conventionally, as a method of removing dust from combustion exhaust gas, an electric dust collector and a bag filter are known, but high-temperature combustion exhaust gas cannot be used as it is, and it has been necessary to cool it to a predetermined temperature. Further, in the case of a film or a nonwoven fabric (felt), since the fineness is small and thin, dust collection performance is high, but it is easily clogged at an early stage, and there is a problem that it cannot be used for high-temperature gas. Although the ceramic foam has a high porosity and a low airflow resistance, it has a problem that dust collected once is easily discharged.
【０００４】 さらに、アルミナ骨材粒子をガラスボン
ドで結合したフィルターも提案されているが、煤塵類の
濾過性能のバラツキが大きく、しかも熱スポール性に劣
り、逆洗効果も小さいという問題があった。[0004] Furthermore, a filter in which alumina aggregate particles are bonded by a glass bond has been proposed, but there is a problem that the filtration performance of dust is largely varied, the thermal sparing property is poor, and the backwashing effect is small. .
【０００５】[0005]
【発明が解決しようとする課題】 本発明は上記した従
来の課題に鑑みてなされたものであり、その目的とする
ところは、均一で安定な煤塵類除去ができ、長寿命なフ
ィルターを提供することである。SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a filter which can remove dust uniformly and stably and has a long life. That is.
【０００６】[0006]
【課題を解決するための手段】 すなわち、本発明によ
れば、セラミック骨材粒子を無機質結合材で結合して構
成された多孔質のセラミックフィルターであって、該骨
材粒子はＳｉＣからなるとともに、その５０％粒子径の
５０％以下の粒度のものが全体の１０％以下であり、該
セラミックフィルターの気孔率が２５〜５０％で、その
最大気孔径が平均気孔径の２倍以下であり、かつ、単位
体積当たりの通気量（差圧１０ｍｍＡｑ）が０．２〜
０．５リッター／ｍｉｎで、室温での曲げ強度が２００
ｋｇ／ｃｍ2以上であることを特徴とするセラミックフ
ィルター、が提供される。That is, according to the present invention, there is provided a porous ceramic filter formed by bonding ceramic aggregate particles with an inorganic binder, wherein the aggregate particles are made of SiC. The ceramic filter has a particle size of 50% or less of the 50% particle size of 10% or less of the whole, the porosity of the ceramic filter is 25 to 50%, and the maximum pore size is not more than twice the average pore size. And the amount of air per unit volume (differential pressure 10 mmAq) is 0.2 to
0.5 liter / min, bending strength at room temperature is 200
a ceramic filter characterized by being at least kg / cm 2 .
【０００７】 なお、無機質結合材はガラス質であって
も結晶質であってもよい。結合材がガラス質の場合に
は、５００〜９００℃の比較的低温度のガスに使用する
ことが好ましく、結合材が結晶質の場合には１０００℃
以上の高温ガスに適用することが好ましい。[0007] The inorganic binder may be glassy or crystalline. When the binder is glassy, it is preferable to use a gas at a relatively low temperature of 500 to 900 ° C., and when the binder is crystalline, 1000 ° C.
It is preferable to apply to the above high-temperature gas.
【０００８】[0008]
【発明の実施の形態】 本発明のセラミックフィルター
は、セラミック骨材粒子を無機質結合材で結合して構成
された多孔質のセラミックフィルターで、骨材粒子はＳ
ｉＣから構成されており、骨材粒子の粒度は、５０％粒
子径の５０％以下の粒度のものが全体の１０％以下を占
めるものである。また、セラミックフィルターの気孔率
は２５〜５０％で、その最大気孔径は平均気孔径の２倍
以下である。本発明のセラミックフィルターは、上記の
ように、骨材粒子の粒度を極めて狭くして微粒骨材を少
なくすることによって、気孔径分布をシャープにしたの
で、均一で安定な煤塵など不純物除去を達成できるとと
もに、目詰まりし難く長寿命なセラミックフィルターを
提供することができる。BEST MODE FOR CARRYING OUT THE INVENTION The ceramic filter of the present invention is a porous ceramic filter formed by binding ceramic aggregate particles with an inorganic binder, wherein the aggregate particles are S
It is composed of iC, and the particle size of the aggregate particles is 50% or less of the 50% particle size, which accounts for 10% or less of the whole. Further, the porosity of the ceramic filter is 25 to 50%, and the maximum pore size is not more than twice the average pore size. As described above, the ceramic filter of the present invention has a sharp pore size distribution by extremely narrowing the particle size of the aggregate particles and reducing the fine aggregate, thereby achieving uniform and stable removal of impurities such as dust. It is possible to provide a long-life ceramic filter which is not easily clogged.
【０００９】 以下、本発明のセラミックフィルターを
詳細に説明する。本発明は、セラミック骨材粒子を無機
質結合材で結合して構成された多孔質のセラミックフィ
ルターである。本発明で用いる骨材粒子は、炭化珪素
（ＳｉＣ）から構成されていることが必要である。Ｓｉ
Ｃは、熱伝導率が高く、熱スポール性に優れるので、得
られるセラミックフィルターは、燃焼排ガスのような高
温ガスに対しても好ましく適用することができる。Hereinafter, the ceramic filter of the present invention will be described in detail. The present invention is a porous ceramic filter formed by combining ceramic aggregate particles with an inorganic binder. The aggregate particles used in the present invention need to be composed of silicon carbide (SiC). Si
Since C has high thermal conductivity and excellent thermal spalling properties, the obtained ceramic filter can be preferably applied to high-temperature gases such as combustion exhaust gas.
【００１０】 この骨材粒子の粒度は、５０％粒子径の
５０％以下の粒度のものが全体の１０％以下を占めるも
のである。すなわち、このように、骨材粒子の粒度幅を
狭くして粒度を揃え、しかも微粒子を極力少なくするこ
とにより、得られる多孔質フィルターの気孔径分布を狭
くシャープにした。Regarding the particle size of the aggregate particles, those having a particle size of 50% or less of the 50% particle size occupy 10% or less of the whole. That is, in this way, the pore size distribution of the obtained porous filter was narrowed and sharpened by narrowing the particle size width of the aggregate particles to make the particle size uniform and reducing the fine particles as much as possible.
【００１１】 本発明に用いる無機質結合材の組成とし
ては、骨材粒子の組成と同一であっても異質であっても
よい。また、結合材の状態も、ガラス質でも結晶質でも
よい。結合材がガラス質の場合には、比較的低温度な略
５００〜９００℃の排ガスに対して適用されるが、結合
材が結晶質の場合、低温から高温の広い範囲の排ガスに
対して適用でき、好ましい。なお、結合材が結晶質の場
合、結晶が生成する過程で骨材粒子を結合するものと、
骨材粒子が高温で再結合したものとがある。The composition of the inorganic binder used in the present invention may be the same as or different from the composition of the aggregate particles. The state of the binder may be glassy or crystalline. When the binder is glassy, it is applied to exhaust gas of relatively low temperature of about 500 to 900 ° C, but when the binder is crystalline, it is applied to exhaust gas in a wide range from low temperature to high temperature. Yes, it is. In the case where the binder is crystalline, the binder binds aggregate particles in the process of forming crystals,
Some aggregate particles have recombined at high temperatures.
【００１２】 上記のように、セラミック骨材粒子を無
機質結合材で結合して多孔質のセラミックフィルターが
作製されるが、このセラミックフィルターの形状は特に
限定されず、チューブ状（パイプ状）でも板状でも任意
な形状に成形することができる。セラミックフィルター
の気孔率は２５〜５０％とすることが重要である。気孔
率が２５％未満では、早期に目詰まりし、一方、５０％
を超えると結合材による結合力が弱くなり骨材粒子の目
こぼれが生じる。As described above, a porous ceramic filter is produced by bonding ceramic aggregate particles with an inorganic binder, but the shape of the ceramic filter is not particularly limited, and a tube-shaped (pipe-shaped) plate may be used. It can be molded into any shape. It is important that the porosity of the ceramic filter be 25 to 50%. If the porosity is less than 25%, clogging occurs early, while 50%
If the ratio exceeds the range, the bonding force of the bonding material is weakened, and the aggregate particles are spilled.
【００１３】 また、セラミックフィルターの気孔径分
布としては、最大気孔径が平均気孔径の２倍以下である
ことが重要である。このように、気孔径分布が狭く気孔
径が揃っているので、本発明のセラミックフィルター
は、均一で安定な不純物除去が可能になった。[0013] As for the pore size distribution of the ceramic filter, it is important that the maximum pore size is not more than twice the average pore size. As described above, since the pore diameter distribution is narrow and the pore diameters are uniform, the ceramic filter of the present invention can remove impurities uniformly and stably.
【００１４】 更に、本発明のセラミックフィルター
は、単位体積当たりの通気量（差圧１０ｍｍＡｑ）が
０．２〜０．５リッター／ｍｉｎの範囲にあることが重
要である。通気量が０．２リッター／ｍｉｎ未満の場
合、フィルターが早期に目詰まりし、通気抵抗が大きく
なる。一方、通気量が０．５リッター／ｍｉｎを超える
と、不純物の捕集効率が低下するという問題がある。Furthermore, it is important that the ceramic filter of the present invention has a ventilation volume per unit volume (differential pressure of 10 mmAq) in the range of 0.2 to 0.5 liter / min. When the ventilation amount is less than 0.2 liter / min, the filter is clogged early and the ventilation resistance is increased. On the other hand, if the ventilation rate exceeds 0.5 liter / min, there is a problem that the efficiency of collecting impurities is reduced.
【００１５】 このセラミックフィルターは、室温にお
ける曲げ強度が２００ｋｇ／ｃｍ2以上であることが必
要である。セラミックフィルターは一端で保持されて使
用されることが多く、自重に耐え得る強度が必要であ
り、そのため、曲げ強度が２００ｋｇ／ｃｍ2未満では
自重で折れる可能性がある。This ceramic filter needs to have a bending strength at room temperature of 200 kg / cm 2 or more. A ceramic filter is often used while being held at one end, and needs to have a strength that can withstand its own weight. Therefore, if the bending strength is less than 200 kg / cm 2 , it may be broken by its own weight.
【００１６】[0016]
【実施例】 次に、本発明を実施例を用いてさらに詳し
く説明するが、本発明はこれらの実施例に限られるもの
ではない。 （実施例１）表１に示す粒度のＳｉＣ原料（骨材粒子）
を用い、無機質結合材としてＡｌ2Ｏ3が３０重量％、Ｂ
2Ｏ3が４５重量％、ＣａＯが１５重量％、ＭｇＯが１０
重量％の組成で、表１のようにガラス質または結晶質と
変えるとともに、その通気量、気孔率、気孔径及び室温
での曲げ強度を変化させて、外径６０ｍｍ、内径４０ｍ
ｍ、長さ１５００ｍｍの一端を封じたパイプ形状のセラ
ミックフィルターを作製した。EXAMPLES Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. (Example 1) SiC raw material (aggregate particles) having the particle size shown in Table 1
And 30% by weight of Al 2 O 3 as an inorganic binder,
2 O 3 45% by weight, CaO 15% by weight, MgO 10%
By changing the composition to be glassy or crystalline as shown in Table 1 and changing the air permeability, porosity, pore diameter and bending strength at room temperature, the outer diameter is 60 mm and the inner diameter is 40 m.
A pipe-shaped ceramic filter having a length of 1,500 mm and an end sealed was prepared.
【００１７】 なお、配合割合は、ＳｉＣ原料（骨材粒
子）１００重量部に対し、無機質結合材１２重量部と
し、それに有機バインダー、水を添加し、混練した。次
いで、突き固め成形機で上記パイプ状に成形後、乾燥し
た。その後、この成形体を無機質結合材の強度が発現す
る温度（ガラス質の場合は１３００℃、結晶質の場合は
１６００℃）で焼成し、セラミックフィルターを得た。The mixing ratio was 12 parts by weight of the inorganic binder with respect to 100 parts by weight of the SiC raw material (aggregate particles), and an organic binder and water were added thereto and kneaded. Next, it was dried after being formed into the pipe shape by a tamping molding machine. Thereafter, the formed body was fired at a temperature at which the strength of the inorganic binder is exhibited (1300 ° C. for a glassy material and 1600 ° C. for a crystalline material) to obtain a ceramic filter.
【００１８】 このセラミックフィルターに対して、焼
却炉排ガスを流し、不純物の除去性能を測定した。な
お、不純物の除去性能は、７０％以上を合格（○）、７
０％未満を不合格（×）とした。結果を表１に示す。な
お、室温での曲げ強度は、ＪＩＳ Ｒ２２１３に基づい
て測定した。An incinerator exhaust gas was passed through the ceramic filter, and the performance of removing impurities was measured. In addition, the removal performance of impurities passed 70% or more (o), 7
Less than 0% was rejected (x). Table 1 shows the results. The bending strength at room temperature was measured based on JIS R2213.
【００１９】[0019]
【表１】 [Table 1]
【００２０】（実施例２）表２に示す粒度のＳｉＣ原料
を用い、形状が３００ｍｍ×３００ｍｍ×２０ｍｍ（厚
さ）の板状のフィルターとした以外は、実施例１と同じ
方法にて、セラミックフィルターを得た。実施例１と同
様に、焼却炉排ガスを流し、不純物の除去性能を測定し
た。結果を表２に示す。Example 2 A ceramic was produced in the same manner as in Example 1 except that a SiC raw material having the particle size shown in Table 2 was used and a plate-shaped filter having a shape of 300 mm × 300 mm × 20 mm (thickness) was used. A filter was obtained. In the same manner as in Example 1, the exhaust gas from the incinerator was flown, and the performance of removing impurities was measured. Table 2 shows the results.
【００２１】[0021]
【表２】 [Table 2]
【００２２】（評価）表１、表２の結果からわかるよう
に、本願発明に規定する粒度、気孔率、気孔径、通気量
などの範囲を逸脱する場合には、不純物の除去性能に劣
ることが判明した。(Evaluation) As can be seen from the results in Tables 1 and 2, when the particle size, porosity, pore diameter, air permeability and the like are out of the ranges specified in the present invention, the performance of removing impurities is inferior. There was found.
【００２３】[0023]
【発明の効果】 以上説明したように、本発明のセラミ
ックフィルターによれば、均一で安定な煤塵類の不純物
除去ができ、熱スポール性に優れた長寿命なフィルター
を提供することができる。As described above, according to the ceramic filter of the present invention, it is possible to uniformly and stably remove impurities of dust, and to provide a long-life filter excellent in thermal spalling property.
Claims (3)
合して構成された多孔質のセラミックフィルターであっ
て、 該骨材粒子はＳｉＣからなるとともに、その５０％粒子
径の５０％以下の粒度のものが全体の１０％以下であ
り、 該セラミックフィルターの気孔率が２５〜５０％で、そ
の最大気孔径が平均気孔径の２倍以下であり、 かつ、単位体積当たりの通気量（差圧１０ｍｍＡｑ）が
０．２〜０．５リッター／ｍｉｎで、室温での曲げ強度
が２００ｋｇ／ｃｍ2以上であることを特徴とするセラ
ミックフィルター。1. A porous ceramic filter formed by bonding ceramic aggregate particles with an inorganic binder, wherein the aggregate particles are made of SiC and have a particle size of 50% or less of a 50% particle size thereof. Is less than 10% of the whole, the porosity of the ceramic filter is 25 to 50%, the maximum pore diameter is less than twice the average pore diameter, and the air permeability per unit volume (differential pressure) (10 mmAq) 0.2 to 0.5 liter / min, and a bending strength at room temperature of 200 kg / cm 2 or more.
１記載のセラミックフィルター。2. The ceramic filter according to claim 1, wherein said inorganic binder is glassy.
記載のセラミックフィルター。3. The method according to claim 1, wherein said inorganic binder is crystalline.
The ceramic filter as described.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5929098A JPH11253722A (en) | 1998-03-11 | 1998-03-11 | Ceramic filter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5929098A JPH11253722A (en) | 1998-03-11 | 1998-03-11 | Ceramic filter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH11253722A true JPH11253722A (en) | 1999-09-21 |
Family
ID=13109116
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5929098A Pending JPH11253722A (en) | 1998-03-11 | 1998-03-11 | Ceramic filter |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH11253722A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1170270A1 (en) * | 2000-01-17 | 2002-01-09 | Ngk Insulators, Ltd. | Honeycomb structure and method for manufacture thereof |
| WO2002062726A1 (en) * | 2001-02-02 | 2002-08-15 | Ngk Insulators,Ltd. | Honeycomb structure and method for preparation thereof |
| JP2002274947A (en) * | 2001-03-16 | 2002-09-25 | Ibiden Co Ltd | Sintered porous silicon carbide, method for manufacturing the same and filter for diesel particulate |
| WO2003082771A1 (en) * | 2002-03-29 | 2003-10-09 | Ngk Insulators, Ltd. | Porous material and method for production thereof |
| EP1493722A1 (en) * | 2002-03-29 | 2005-01-05 | Ngk Insulators, Ltd. | Silicon carbide based porous material and method for production thereof |
| WO2005064128A1 (en) * | 2003-12-25 | 2005-07-14 | Ibiden Co., Ltd. | Exhaust gas purifying device and method for recovering exhaust gas purifying device |
-
1998
- 1998-03-11 JP JP5929098A patent/JPH11253722A/en active Pending
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1170270A1 (en) * | 2000-01-17 | 2002-01-09 | Ngk Insulators, Ltd. | Honeycomb structure and method for manufacture thereof |
| EP1170270A4 (en) * | 2000-01-17 | 2006-02-22 | Ngk Insulators Ltd | Honeycomb structure and method for manufacture thereof |
| WO2002062726A1 (en) * | 2001-02-02 | 2002-08-15 | Ngk Insulators,Ltd. | Honeycomb structure and method for preparation thereof |
| JP2002234779A (en) * | 2001-02-02 | 2002-08-23 | Ngk Insulators Ltd | Honeycomb structure and production method therefor |
| US6764742B2 (en) | 2001-02-02 | 2004-07-20 | Ngk Insulators, Ltd. | Honeycomb structure body and production method thereof |
| JP2002274947A (en) * | 2001-03-16 | 2002-09-25 | Ibiden Co Ltd | Sintered porous silicon carbide, method for manufacturing the same and filter for diesel particulate |
| EP1493722A1 (en) * | 2002-03-29 | 2005-01-05 | Ngk Insulators, Ltd. | Silicon carbide based porous material and method for production thereof |
| WO2003082771A1 (en) * | 2002-03-29 | 2003-10-09 | Ngk Insulators, Ltd. | Porous material and method for production thereof |
| EP1493722A4 (en) * | 2002-03-29 | 2006-02-22 | Ngk Insulators Ltd | Silicon carbide based porous material and method for production thereof |
| US7452591B2 (en) | 2002-03-29 | 2008-11-18 | Ngk Insulators, Ltd. | Silicon carbide based porous material and method for production thereof |
| US7473464B2 (en) | 2002-03-29 | 2009-01-06 | Ngk Insulators, Ltd. | Porous material and method for production thereof |
| US8092740B2 (en) | 2002-03-29 | 2012-01-10 | Ngk Insulators, Ltd. | Method of manufacturing a porous material |
| US8173054B2 (en) | 2002-03-29 | 2012-05-08 | Ngk Insulators, Ltd. | Silicon carbide based porous material and method for production thereof |
| WO2005064128A1 (en) * | 2003-12-25 | 2005-07-14 | Ibiden Co., Ltd. | Exhaust gas purifying device and method for recovering exhaust gas purifying device |
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