JPH05253469A - Method and device for producing ceramic powder - Google Patents
Method and device for producing ceramic powderInfo
- Publication number
- JPH05253469A JPH05253469A JP4051475A JP5147592A JPH05253469A JP H05253469 A JPH05253469 A JP H05253469A JP 4051475 A JP4051475 A JP 4051475A JP 5147592 A JP5147592 A JP 5147592A JP H05253469 A JPH05253469 A JP H05253469A
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- reaction chamber
- ceramic powder
- producing
- temperature
- reaction
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- Compositions Of Oxide Ceramics (AREA)
- Oxygen, Ozone, And Oxides In General (AREA)
- Physical Or Chemical Processes And Apparatus (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、セラミックス粉体の製
造方法、更に詳細には、噴霧熱分解法によるセラミック
ス粉体の製造方法およびこれに用いる装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing ceramic powder, and more particularly to a method for producing ceramic powder by a spray pyrolysis method and an apparatus used therefor.
【０００２】[0002]
【従来の技術】近年、セラミックスに対する機能性の向
上が要求されており、高純度、組成均一性、微細性に優
れるセラミックス粉体を製造する観点から、気相または
液相を介するセラミックス粉体の製造方法が注目されて
いる。このうち、液相を介する方法としては、噴霧熱分
解法が注目されている。一般に、噴霧熱分解法では、金
属塩溶液（原料溶液）を、熱分解が起こる温度以上の高
温に保持した雰囲気中に微細な液滴として噴霧し、極く
短時間で溶媒の蒸発、金属塩の析出、その熱分解を行な
い、セラミックス微粉末を製造する。2. Description of the Related Art In recent years, it has been required to improve the functionality of ceramics, and from the viewpoint of producing ceramics powders having high purity, compositional uniformity and fineness, the ceramics powders in the gas phase or liquid phase are used. The manufacturing method is drawing attention. Among them, the spray pyrolysis method has been attracting attention as a method via a liquid phase. In general, in the spray pyrolysis method, a metal salt solution (raw material solution) is sprayed as fine droplets in an atmosphere kept at a temperature higher than the temperature at which pyrolysis occurs, and the solvent is evaporated in a very short time to cause metal salt Of ceramics and its thermal decomposition to produce ceramic fine powder.
【０００３】[0003]
【発明が解決しようとする課題】しかしながら、このよ
うな従来の噴霧熱分解法は、未だ実験室的段階に留まっ
ている状況であり反応の達成に重点が置かれていた。従
って、反応達成率を向上させるために反応温度を上昇さ
せる必要があり、温度を上昇させればさせる程、急激な
反応となり、噴霧される液滴の表面と内部とでは反応の
進行が著しく異なってくることになる。即ち、液滴の表
面は高温にさらされているため、反応および溶媒蒸発が
急激に進行して固化し殻を形成する。一方、内部は、表
面より熱伝達が遅れるため、液状のまま表面の殻に閉じ
込められる。その後、内部の液の反応や溶媒蒸発が進行
すると、表面の殻が膨張、破壊されるかまたは殻の微小
な間隙を通過して溶媒蒸気等が外部に放出される。However, such a conventional spray pyrolysis method is still in the laboratory stage, and emphasis has been placed on achieving the reaction. Therefore, it is necessary to raise the reaction temperature in order to improve the reaction achievement rate, and the higher the temperature, the more rapid the reaction becomes, and the progress of the reaction is significantly different between the surface and the inside of the sprayed droplets. Will come. That is, since the surface of the droplet is exposed to high temperature, the reaction and solvent evaporation rapidly proceed to solidify and form a shell. On the other hand, the heat transfer inside the surface is delayed compared to the surface, so that the liquid is confined in the shell of the surface as a liquid. After that, when the reaction of the liquid inside or the evaporation of the solvent proceeds, the shell on the surface is expanded or destroyed, or the solvent vapor or the like is released to the outside through a minute gap in the shell.
【０００４】この際、膨張、破壊、間隙からの通過のい
ずれになるかは噴霧される原料溶液の組成や反応温度等
により異なるが、いずれにしても製造されるセラミック
ス粉体の性状に悪影響を及ぼすこととなる。この結果、
従来の噴霧熱分解法においては、セラミックス微粉体は
得られるものの、粒子の形状、みかけ比重、流動性等を
調整できず、セラミックスの機能性の向上という要求を
満足できないという課題があった。本発明は、このよう
な従来技術の有する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、粒子の形状、みかけ比重、流
動性等が良好なセラミックス粉体の噴霧熱分解法による
製造方法およびこれに用いる装置を提供することにあ
る。At this time, which of expansion, destruction and passage through the gap depends on the composition of the raw material solution to be sprayed, the reaction temperature and the like, but in any case, the properties of the ceramic powder produced are adversely affected. Will affect. As a result,
In the conventional spray pyrolysis method, although fine ceramic powder was obtained, there was a problem that the shape, apparent specific gravity, fluidity, etc. of the particles could not be adjusted, and the demand for improved ceramic functionality could not be satisfied. The present invention has been made in view of such problems of the conventional technology,
It is an object of the invention to provide a method for producing a ceramic powder having good particle shape, apparent specific gravity, fluidity and the like by a spray pyrolysis method and an apparatus used therefor.
【０００５】[0005]
【課題を解決するための手段】本発明者らは、前記課題
を解決すべく鋭意研究した結果、原料溶液を導入噴霧す
る反応室に温度分布を設けることにより、液滴表面と内
部との反応速度の差を制御できることを見出し、本発明
を完成するに至った。従って、本発明の製造方法は、原
料溶液を所定温度の反応室に導入噴霧し、熱分解してセ
ラミックス粉体を製造するに当り、前記反応室に温度分
布を設け、反応速度を制御したことを特徴とする。Means for Solving the Problems As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that the reaction between the surface of the liquid droplet and the inside of the liquid droplet is caused by providing a temperature distribution in the reaction chamber for introducing and spraying the raw material solution. The inventors have found that the speed difference can be controlled, and have completed the present invention. Therefore, in the production method of the present invention, when the raw material solution is introduced and sprayed into the reaction chamber at a predetermined temperature and pyrolyzed to produce ceramic powder, a temperature distribution is provided in the reaction chamber to control the reaction rate. Is characterized by.
【０００６】また、本発明の製造装置は、原料溶液を所
定温度の反応室に導入噴霧し、熱分解してセラミックス
粉体を製造する装置において、噴霧器と、反応室と、こ
の反応室を包囲する加熱手段とを備え、前記加熱手段
が、検温手段を備えた複数の加熱器を有することを特徴
とする。Further, the production apparatus of the present invention is an apparatus for producing a ceramic powder by introducing and spraying a raw material solution into a reaction chamber at a predetermined temperature, and producing a ceramic powder by enclosing the atomizer, the reaction chamber, and the reaction chamber. And a plurality of heaters each having a temperature measuring means.
【０００７】[0007]
【作用】本発明においては、前記反応室に温度分布を設
けたため、噴霧される液滴の表面と内部との反応速度の
差を制御できる。また、反応室の温度分布を３段階以上
とすることにより、前記反応速度の差を一層微妙に制御
することができ、得られるセラミックス粉体の性状も一
層優れたものとなる。In the present invention, since the temperature distribution is provided in the reaction chamber, it is possible to control the difference in reaction speed between the surface and the inside of the sprayed droplets. Further, by setting the temperature distribution in the reaction chamber to three stages or more, the difference in the reaction rates can be controlled more delicately, and the properties of the obtained ceramic powder become more excellent.
【０００８】さらに、反応室の入口部の温度を、反応室
の他の部分より低温に設定することにより、反応初期に
おいて反応速度を抑制し、液滴の表面および内部の反応
率を近似させ、表面の固化に伴う殻の形成を遅延させる
ことができる。これにより、表面が固化した後における
内部からの蒸気の通過量を低減することができ、得られ
るセラミックス粉体粒子の膨張や破壊を抑制することが
できる。Furthermore, by setting the temperature of the inlet of the reaction chamber to be lower than that of the other parts of the reaction chamber, the reaction rate is suppressed in the initial stage of the reaction, and the reaction rate on the surface and inside of the droplet is approximated. The formation of shells with surface solidification can be delayed. As a result, the amount of vapor passing from the inside after the surface is solidified can be reduced, and expansion and destruction of the obtained ceramic powder particles can be suppressed.
【０００９】[0009]
【実施例】以下、本発明を、図面を参照して実施例およ
び比較例により説明する。図１は、本発明の製造装置の
一例を示す断面図である。同図において、この製造装置
１は、噴霧器１０と、反応室２０と、この反応室２０を
包囲する加熱手段３０を備える。この加熱手段３０は、
加熱器、例えば、電気ヒータ３１、３２、３３を備え、
それぞれ加熱領域２１、２２、２３を構成している。こ
れら電気ヒータは、検温手段、例えば、熱電対４１〜４
６を備える。そして、検温手段４４、４５、４６は、反
応室２０内部に貫通しており、検温手段４１、４２、４
３との対応で反応室２０に温度分布を設定することを可
能にするとともに、その温度制御を容易ならしめてい
る。EXAMPLES The present invention will be described below with reference to the drawings through examples and comparative examples. FIG. 1 is a sectional view showing an example of the manufacturing apparatus of the present invention. In the figure, the manufacturing apparatus 1 includes a sprayer 10, a reaction chamber 20, and a heating means 30 surrounding the reaction chamber 20. This heating means 30 is
A heater, for example an electric heater 31, 32, 33,
The heating areas 21, 22 and 23 are respectively configured. These electric heaters are temperature measuring means, for example, thermocouples 41 to 4
6 is provided. The temperature measuring means 44, 45, 46 penetrate the inside of the reaction chamber 20, and the temperature measuring means 41, 42, 4,
In correspondence with No. 3, it is possible to set the temperature distribution in the reaction chamber 20, and the temperature control is facilitated.
【００１０】また、原料溶液５０は、微粒化用ガス（例
えば、エアー、酸素、窒素、アルゴンガス）５１および
噴霧器、例えば、２流体ノズル１０を介して反応室２０
内に噴霧される。次いで、噴霧された液滴５２はキャリ
アガス（例えば、エアー、窒素、アルゴンガス）５３に
より粉体出口６０の方向に同伴される。この同伴過程に
おいて、液滴５２は温度制御された加熱領域２１、２
２、２３を通過しながら反応し固化してセラミックス粉
体を生成し、温風７０を介して粉体出口６０から取り出
される。The raw material solution 50 is supplied to the reaction chamber 20 through a atomizing gas (for example, air, oxygen, nitrogen, argon gas) 51 and an atomizer, for example, the two-fluid nozzle 10.
Is sprayed in. Next, the atomized droplets 52 are entrained by the carrier gas (for example, air, nitrogen, argon gas) 53 toward the powder outlet 60. During this entrainment process, the droplet 52 is heated by the temperature-controlled heating regions 21, 2
While passing 2 and 23, they react and solidify to produce a ceramic powder, which is taken out from the powder outlet 60 via the warm air 70.
【００１１】（実施例１、２および比較例１、２）硝酸
アルミニウムとケイ酸エチルに、水とエタノールとの混
合液（５０：５０容量％）を加え、ムライト（３Ａｌ2
Ｏ3 ・２ＳｉＯ2 ）組成として０．２ｍｏｌ／ｌとなる
ように調整し、得られた溶液を原料溶液とした。この原
料溶液と上述の製造装置１を用いてセラミックス粉体を
製造した。加熱領域２１〜２３の設定温度、得られたセ
ラミックス粉体の物性、反応率およびこれら粉体を用い
て製造した焼結体の性状を、表１に示す。(Examples 1 and 2 and Comparative Examples 1 and 2) A mixed solution of water and ethanol (50: 50% by volume) was added to aluminum nitrate and ethyl silicate, and mullite (3Al 2
The O 3 · 2SiO 2 ) composition was adjusted to 0.2 mol / l, and the obtained solution was used as a raw material solution. Ceramic powder was manufactured using this raw material solution and the manufacturing apparatus 1 described above. Table 1 shows the set temperatures of the heating regions 21 to 23, the physical properties of the obtained ceramic powder, the reaction rate, and the properties of the sintered body produced using these powders.
【００１２】[0012]
【表１】 [Table 1]
【００１３】表１に示すように、実施例１および２によ
り得られたセラミックス粉体は、優れた物性を有した。
また、反応率も優れているとともにこれらを用いて製造
した焼結体の性状も良好であった。As shown in Table 1, the ceramic powders obtained in Examples 1 and 2 had excellent physical properties.
In addition, the reaction rate was excellent and the properties of the sintered body produced using them were good.
【００１４】以上、本発明の一実施例につき説明した
が、本発明はこれに限定されるものではなく、本発明の
要旨の範囲内において種々の変形が可能である。例え
ば、製造できるセラミックス粉体としては、ムライトの
みならずアルミナ、酸化鉄、酸化亜鉛、スピネル、酸化
チタン、ジルコニア等が挙げられる。また、原料溶液の
混合組成および用いる溶媒などは、製造すべきセラミッ
クス粉体により適宜変更し得る。また、加熱領域２１〜
２３の設定温度および加熱領域の個数も、製造すべきセ
ラミックス粉体により適宜変更し得る。更に、各加熱領
域に検温手段を２個配設したが、１個であってもよい。
また、温度分布を設けるに必ずしも検温手段を必要とせ
ず、電気抵抗の異なる発熱体を複数設置してもよい。Although one embodiment of the present invention has been described above, the present invention is not limited to this, and various modifications can be made within the scope of the gist of the present invention. For example, examples of the ceramic powder that can be produced include mullite, alumina, iron oxide, zinc oxide, spinel, titanium oxide, and zirconia. Further, the mixed composition of the raw material solution, the solvent used, and the like can be appropriately changed depending on the ceramic powder to be produced. In addition, the heating region 21 to
The set temperature of 23 and the number of heating regions can also be appropriately changed depending on the ceramic powder to be manufactured. Further, although two temperature measuring means are provided in each heating area, one temperature measuring means may be provided.
Further, the temperature measuring means is not necessarily required to provide the temperature distribution, and a plurality of heating elements having different electric resistances may be installed.
【００１５】[0015]
【発明の効果】以上説明したように、本発明によれば、
反応室に温度分布を設け、噴霧液滴の反応速度を制御す
ることとしたため、粒子の形状、みかけ比重、流動性等
が良好なセラミックス粉体の噴霧熱分解法による製造方
法およびこれに用いる装置を提供することができる。As described above, according to the present invention,
Since a temperature distribution is provided in the reaction chamber to control the reaction rate of spray droplets, a method for producing a ceramic powder by spray pyrolysis method, which has good particle shape, apparent specific gravity, fluidity, etc., and an apparatus used therefor Can be provided.
【図１】本発明の製造装置の一実施例を示す断面図であ
る。FIG. 1 is a sectional view showing an embodiment of a manufacturing apparatus of the present invention.
１ セラミックス粉体製造装置 １０ 噴霧器 ２０ 反応室 ２１ 加熱領域 ２２ 加熱領域 ２３ 加熱領域 ３０ 加熱手段 ３１ 加熱器 ３２ 加熱器 ３３ 加熱器 ４１ 検温手段 ４２ 検温手段 ４３ 検温手段 ４４ 検温手段 ４５ 検温手段 ４６ 検温手段 ５０ 原料溶液 ５１ 微粒化用ガス ５２ 噴霧液滴 ５３ キャリアガス ６０ 粉体出口 ７０ 温風 DESCRIPTION OF SYMBOLS 1 Ceramics powder manufacturing apparatus 10 Sprayer 20 Reaction chamber 21 Heating area 22 Heating area 23 Heating area 30 Heating means 31 Heating device 32 Heating device 33 Heating device 41 Temperature measuring means 42 Temperature measuring means 43 Temperature measuring means 44 Temperature measuring means 45 Temperature measuring means 46 Temperature measuring means 50 raw material solution 51 atomizing gas 52 atomized droplets 53 carrier gas 60 powder outlet 70 hot air
───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.5 識別記号 庁内整理番号 ＦＩ 技術表示箇所 // Ｃ０１Ｂ 13/34 8516−4Ｇ (72)発明者 伊藤 崇 神奈川県横浜市緑区池辺町3847 大川原化 工機株式会社内─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. 5 Identification number Reference number within the agency FI Technical display location // C01B 13/34 8516-4G (72) Inventor Takashi Ito 3847 Ikebe-cho, Midori-ku, Yokohama-shi, Kanagawa Okawara Kakoki Co., Ltd.
Claims (4)
し、熱分解してセラミックス粉体を製造するに当り、前
記反応室に温度分布を設け、反応速度を制御したことを
特徴とするセラミックス粉体の製造方法。1. When a raw material solution is introduced and sprayed into a reaction chamber at a predetermined temperature and pyrolyzed to produce ceramic powder, a temperature distribution is provided in the reaction chamber to control the reaction rate. Method for producing ceramic powder.
し、これに対応して反応速度を制御したことを特徴とす
る請求項１記載のセラミックス粉体の製造方法。2. The method for producing a ceramic powder according to claim 1, wherein the temperature distribution in the reaction chamber is set to three stages or more, and the reaction rate is controlled correspondingly.
り低温に設定することを特徴とする請求項１または２記
載のセラミックス粉体の製造方法。3. The method for producing a ceramic powder according to claim 1, wherein the temperature of the inlet portion of the reaction chamber is set to be lower than that of other portions.
し、熱分解してセラミックス粉体を製造する装置におい
て、噴霧器と、反応室と、この反応室を包囲する加熱手
段とを備え、前記加熱手段が、検温手段を備えた複数の
加熱器を有することを特徴とする装置。4. An apparatus for producing a ceramic powder by injecting and spraying a raw material solution into a reaction chamber at a predetermined temperature, which comprises a sprayer, a reaction chamber, and heating means surrounding the reaction chamber, An apparatus characterized in that the heating means comprises a plurality of heaters equipped with temperature measuring means.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4051475A JPH05253469A (en) | 1992-03-10 | 1992-03-10 | Method and device for producing ceramic powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4051475A JPH05253469A (en) | 1992-03-10 | 1992-03-10 | Method and device for producing ceramic powder |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH05253469A true JPH05253469A (en) | 1993-10-05 |
Family
ID=12887981
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4051475A Pending JPH05253469A (en) | 1992-03-10 | 1992-03-10 | Method and device for producing ceramic powder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH05253469A (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07187763A (en) * | 1993-12-24 | 1995-07-25 | Ngk Insulators Ltd | Production of beta-alumina sintered compact |
| JP2008303111A (en) * | 2007-06-07 | 2008-12-18 | Dai Ichi Kogyo Seiyaku Co Ltd | Metal oxide particulate powder, method for producing metal oxide particulate, and production system therefor |
| JP2010018466A (en) * | 2008-07-09 | 2010-01-28 | Japan Fine Ceramics Center | Reaction chamber for spray thermal decomposition apparatus, and spray thermal decomposition apparatus |
| KR101149019B1 (en) * | 2010-01-05 | 2012-05-24 | 금호석유화학 주식회사 | Apparatus for preparing catalyst for synthesis of carbon nano tube |
| JP2014121704A (en) * | 2012-11-26 | 2014-07-03 | Ohkawara Kakohki Co Ltd | Atomization thermal decomposition treatment apparatus and atomization thermal decomposition treatment method |
| JP2015229622A (en) * | 2014-06-06 | 2015-12-21 | 太平洋セメント株式会社 | Production apparatus of hollow particle |
| JP2016098155A (en) * | 2014-11-25 | 2016-05-30 | 太平洋セメント株式会社 | Method for manufacturing hollow particle |
| JP2018065078A (en) * | 2016-10-18 | 2018-04-26 | 太平洋セメント株式会社 | Atomization thermal decomposition device |
| KR101876870B1 (en) * | 2017-04-20 | 2018-07-12 | 한국생산기술연구원 | Flow device for luquid metal to preventing high-temperature corrosion and its operation method |
-
1992
- 1992-03-10 JP JP4051475A patent/JPH05253469A/en active Pending
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07187763A (en) * | 1993-12-24 | 1995-07-25 | Ngk Insulators Ltd | Production of beta-alumina sintered compact |
| JP2008303111A (en) * | 2007-06-07 | 2008-12-18 | Dai Ichi Kogyo Seiyaku Co Ltd | Metal oxide particulate powder, method for producing metal oxide particulate, and production system therefor |
| JP2010018466A (en) * | 2008-07-09 | 2010-01-28 | Japan Fine Ceramics Center | Reaction chamber for spray thermal decomposition apparatus, and spray thermal decomposition apparatus |
| KR101149019B1 (en) * | 2010-01-05 | 2012-05-24 | 금호석유화학 주식회사 | Apparatus for preparing catalyst for synthesis of carbon nano tube |
| JP2014121704A (en) * | 2012-11-26 | 2014-07-03 | Ohkawara Kakohki Co Ltd | Atomization thermal decomposition treatment apparatus and atomization thermal decomposition treatment method |
| JP2015229622A (en) * | 2014-06-06 | 2015-12-21 | 太平洋セメント株式会社 | Production apparatus of hollow particle |
| JP2016098155A (en) * | 2014-11-25 | 2016-05-30 | 太平洋セメント株式会社 | Method for manufacturing hollow particle |
| JP2018065078A (en) * | 2016-10-18 | 2018-04-26 | 太平洋セメント株式会社 | Atomization thermal decomposition device |
| KR101876870B1 (en) * | 2017-04-20 | 2018-07-12 | 한국생산기술연구원 | Flow device for luquid metal to preventing high-temperature corrosion and its operation method |
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