JP2018149481A - Manufacturing apparatus of microparticle by spray pyrolysis process - Google Patents

Manufacturing apparatus of microparticle by spray pyrolysis process Download PDF

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JP2018149481A
JP2018149481A JP2017046892A JP2017046892A JP2018149481A JP 2018149481 A JP2018149481 A JP 2018149481A JP 2017046892 A JP2017046892 A JP 2017046892A JP 2017046892 A JP2017046892 A JP 2017046892A JP 2018149481 A JP2018149481 A JP 2018149481A
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core tube
furnace core
furnace
particles
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JP6851230B2 (en
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広樹 山崎
Hiroki Yamazaki
広樹 山崎
雄一 館山
Yuichi Tateyama
雄一 館山
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Taiheiyo Cement Corp
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Abstract

PROBLEM TO BE SOLVED: To provide an apparatus capable of stably manufacturing microparticles by a spray pyrolysis process, the apparatus preventing a furnace core tube from cracking and splitting caused by thermal shock or thermal distortion to improve durability of the furnace core tube.SOLUTION: In a manufacturing apparatus of microparticles, a raw material solution is sprayed into a spray pyrolysis apparatus having a drying zone and a heating zone and subjected to drying and pyrolysis. A furnace core tube of a furnace is made of ceramics and linearly divided into two or more parts in the longitudinal direction. The parting planes are tightly adhered to each other and have an angle of 45 degrees or more and 70 degrees or less to an arc tangent of the upper edge face of the furnace core tube.SELECTED DRAWING: Figure 1

Description

本発明は、噴霧熱分解法による微小粒子の製造装置に関する。   The present invention relates to an apparatus for producing fine particles by a spray pyrolysis method.

従来の噴霧熱分解法は、超音波霧化装置やノズルを用いて、管状炉などの加熱炉に原料溶液を霧状(ミスト状)に噴霧し、炉内で加熱処理して液滴を乾燥させて、微小粒子や中空粒子を合成し、回収する装置を用いた製造方法である(特許文献1、2)。この方法は、微小粒子を原料投入・加熱処理・回収まで連続で一気通貫生産するため、反応系外からの不純物の混入を回避でき、かつ大量に生産できる利点がある。
管状炉に使用する炉芯管は、加熱する温度や被加熱処理材料の種類により、金属製、石英製、セラミックス製などが使用されている。
金属製や石英製の炉芯管の場合、高温度中で強酸、強塩基性の原料溶液を用いた場合、原料溶液の成分と反応して脆くなったり、腐食が起こり、得られる粒子に不純物として混入することが起きる。不純物の混入を防止するため、高温度中での耐薬品性、耐熱性などから金属製や石英製より、セラミック素材の方が適していて、広く使用されている。
また、噴霧熱分解法では、一つの管状炉で加熱温度を入り口から出口に向けて高くして反応を行うという特徴がある(特許文献3〜7)。
In the conventional spray pyrolysis method, the raw material solution is sprayed in a mist form (mist form) in a heating furnace such as a tubular furnace using an ultrasonic atomizer or nozzle, and the droplets are dried by heat treatment in the furnace. It is a manufacturing method using a device that synthesizes and collects microparticles and hollow particles (Patent Documents 1 and 2). This method is advantageous in that it can avoid the introduction of impurities from the outside of the reaction system and can be produced in large quantities because the microparticles are continuously produced through the raw material charging, heat treatment, and recovery.
The furnace core tube used for the tubular furnace is made of metal, quartz, ceramics, or the like depending on the temperature to be heated and the kind of the material to be heated.
In the case of a core tube made of metal or quartz, when a strong acid or strong basic raw material solution is used at a high temperature, it reacts with the components of the raw material solution to become brittle or corrode, resulting in impurities in the resulting particles. It happens to be mixed in. In order to prevent impurities from being mixed, ceramic materials are more suitable and widely used than metals or quartz because of their chemical resistance and heat resistance at high temperatures.
Further, the spray pyrolysis method is characterized in that the reaction is carried out by increasing the heating temperature from the entrance to the exit in one tubular furnace (Patent Documents 3 to 7).

特開昭58−223606号公報JP 58-223606 A 特開平3−33011号公報JP-A-3-33011 特開平5−253469号公報JP-A-5-253469 特開平7−265689号公報Japanese Patent Laid-Open No. 7-265689 特開平7−267613号公報JP-A-7-267613 特開平11−236607号公報JP-A-11-236607 特開2009−23888号公報JP 2009-23888 A

しかし、噴霧熱分解法においては、原料溶液のミストを炉心管に直接噴霧し、加熱、分解と一気に短時間で粒子を生産するため、噴霧口付近の高温となっている炉心管に冷たいミストが接触して、サーマルショックが発生する。また、一つの管状炉で加熱温度を入り口から出口に向けて、高くするため、炉芯管に熱歪みが発生する。サーマルショックや熱歪みのため、セラミックス製の炉心管に亀裂や割れが発生して、耐久性が問題となっていた。
従って、本発明の課題は、炉芯管のサーマルショックや熱歪みによる亀裂、割れを防止し、炉芯管の耐久性を改善し、安定して噴霧熱分解法により微粒子を製造可能とする装置を提供することである。
However, in the spray pyrolysis method, the mist of the raw material solution is directly sprayed onto the core tube, and particles are produced in a short time by heating and decomposition. Touching and a thermal shock occurs. Moreover, since the heating temperature is increased from the inlet toward the outlet in one tubular furnace, thermal distortion occurs in the furnace core tube. Due to thermal shock and thermal distortion, cracks and cracks occurred in the ceramic core tube, and durability was a problem.
Therefore, an object of the present invention is to prevent cracks and cracks due to thermal shock and thermal distortion of the furnace core tube, improve the durability of the furnace core tube, and stably produce fine particles by spray pyrolysis. Is to provide.

そこで本発明者は、前記課題を解決すべく種々検討した結果、円筒状の炉芯管として、分割面の角度が特定範囲になるように、長手方向に分割した分割式炉芯管を用いることにより、炉芯管のサーマルショックや熱歪みによる亀裂、割れを防止し、炉芯管の耐久性を改善し、安定して噴霧熱分解法により微粒子が製造できることを見出し、本発明を完成した。   Accordingly, as a result of various studies to solve the above-mentioned problems, the present inventor uses, as a cylindrical furnace core tube, a split furnace core tube that is divided in the longitudinal direction so that the angle of the dividing surface falls within a specific range. Thus, it was found that cracks and cracks due to thermal shock and thermal distortion of the furnace core tube were prevented, durability of the furnace core tube was improved, and fine particles could be stably produced by spray pyrolysis, and the present invention was completed.

すなわち、本発明は、原料溶液を乾燥ゾーン及び加熱ゾーンを有する噴霧熱分解装置に噴霧し、乾燥及び熱分解させる微小粒子の製造装置であって、加熱炉の炉芯管が、長手方向に2以上に直線状に分割され、該分割面は圧着され、該分割面が炉芯管の上端面の弧上接線に対して45度以上70度以下の角度であるセラミック製炉芯管であることを特徴とする熱分解による微小粒子の製造装置を提供するものである。   That is, the present invention is an apparatus for producing microparticles in which a raw material solution is sprayed on a spray pyrolysis apparatus having a drying zone and a heating zone, and dried and pyrolyzed. It is a ceramic furnace core tube that is divided into straight lines as described above, the divided surfaces are crimped, and the divided surfaces are at an angle of 45 degrees or more and 70 degrees or less with respect to the arc tangent of the upper end surface of the furnace core pipe. An apparatus for producing fine particles by thermal decomposition is provided.

本発明の噴霧熱分解装置によれば、耐熱性、耐薬品性に優れたセラミック製の炉芯管の亀裂や割れを防止できるため、安定した微小粒子の製造及び不純物の混入がない均一な高品質の微小粒子が高収率で得られる。   According to the spray pyrolysis apparatus of the present invention, it is possible to prevent cracking and cracking of a ceramic furnace core tube excellent in heat resistance and chemical resistance. Quality microparticles are obtained in high yield.

2分割の炉芯管と分割面の角度を示す図である。It is a figure which shows the angle of a 2-part furnace core pipe and a division surface. 本発明の熱分解装置の概略図である。It is the schematic of the thermal decomposition apparatus of this invention. 本発明の熱分解装置の加熱炉(2分割)の概略図である。It is the schematic of the heating furnace (2 division | segmentation) of the thermal decomposition apparatus of this invention. 従来の熱分解装置の加熱炉の概略図である。It is the schematic of the heating furnace of the conventional thermal decomposition apparatus. 3分割の炉芯管の概略図である。It is the schematic of a 3-part furnace core pipe. 4分割の炉芯管の概略図である。It is the schematic of a 4-part furnace core pipe. 2分割の炉芯管を2段積み重ねた炉芯管の概略図である。It is the schematic of the furnace core tube which piled up two steps of furnace core tubes of 2 divisions.

本発明の熱分解による微粒子の製造装置は、原料溶液を乾燥ゾーン及び加熱ゾーンを有する噴霧熱分解装置に噴霧し、乾燥及び熱分解させる微小粒子の製造装置であって、加熱炉の炉芯管が、長手方向に2以上に直線状に分割され、該分割面は圧着され、該分割面が炉芯管の上端面の弧上接線に対して45度以上70度以下の角度であるセラミック製炉芯管であることを特徴とする。   The apparatus for producing fine particles by pyrolysis according to the present invention is an apparatus for producing fine particles in which a raw material solution is sprayed onto a spray pyrolysis apparatus having a drying zone and a heating zone, and dried and pyrolyzed. Is divided into two or more linearly in the longitudinal direction, the divided surfaces are crimped, and the divided surfaces are at an angle of 45 degrees or more and 70 degrees or less with respect to the arc tangent of the upper end surface of the furnace core tube It is a furnace core tube.

前記加熱炉の炉芯管は、図1に示すように、長手方向に2以上に分割され、該分割面は圧着されており、該分割面が炉芯管の上端面の弧上接線に対して45度以上70度以下の角度である。
長手方向とは、縦炉の場合は縦方向、横型炉の場合は横方向であり、炉芯管の入り口から出口方向を意味する。分割は、図1のように2以上であればよく、好ましくは2以上12以下、より好ましくは2以上8以下、さらに好ましくは2以上6以下である。12を超えて(例えば15)分割した場合、炉芯管の組立(例えば、縦型炉の場合は立てること、横型炉の場合は積むこと)が困難となり、炉芯管を形成できなくなる。また、噴霧熱分解装置内が減圧となるため、炉芯管がずれて、崩れることがあるため、好ましくない。図5は3分割された炉芯管、図6は4分割された炉芯管である。また、図7のように2分割された炉芯管を積み重ねて炉芯管として使用することもできる。
As shown in FIG. 1, the furnace core tube of the heating furnace is divided into two or more in the longitudinal direction, the divided surface is crimped, and the divided surface is against the arc tangent of the upper end surface of the furnace core tube. The angle is not less than 45 degrees and not more than 70 degrees.
The longitudinal direction means the vertical direction in the case of a vertical furnace, the horizontal direction in the case of a horizontal furnace, and means the direction from the entrance to the exit of the furnace core tube. The division may be 2 or more as shown in FIG. 1, preferably 2 or more and 12 or less, more preferably 2 or more and 8 or less, and further preferably 2 or more and 6 or less. If the number exceeds 12 (for example, 15), the assembly of the furnace core tube (for example, standing in the case of a vertical furnace and stacking in the case of a horizontal furnace) becomes difficult, and the furnace core tube cannot be formed. Moreover, since the inside of the spray pyrolysis apparatus is depressurized, the furnace core tube may be displaced and collapse, which is not preferable. FIG. 5 shows a furnace core tube divided into three parts, and FIG. 6 shows a furnace core pipe divided into four parts. Further, as shown in FIG. 7, the furnace core tubes divided into two can be stacked and used as a furnace core tube.

分割面は、圧着されており、元の管状炉の形状に圧着接合されている。この圧着は、炉芯管の外周に供えられたヒーターの設置で実施されるのが好ましい。この分割面の圧着は、何ら接着剤等を介在させずに単なる圧着が好ましい。   The split surfaces are crimped and crimped and joined to the original tubular furnace shape. This crimping is preferably performed by installing a heater provided on the outer periphery of the furnace core tube. The crimping of the divided surfaces is preferably a simple crimping without any adhesive.

該分割面の角度は、図1のように、炉芯管の上端面の弧接線に対して45度以上70度以下である。45度未満であると炉芯管の分割面に亀裂や欠けなどが発生しやすくなるため、好ましくない。70度を越えると、分割面から減圧されている炉芯管内に空気が吸引され、装置内の圧力が高くなり、微小粒子の回収効率の低下、炉芯管内の堆積などが起こり、生産効率が低下するため好ましくない。また、90度の場合には、炉芯管の亀裂や割れが防止できない。   As shown in FIG. 1, the angle of the dividing surface is 45 degrees or more and 70 degrees or less with respect to the arc tangent of the upper end surface of the furnace core tube. If it is less than 45 degrees, cracks and chips are likely to occur on the split surface of the furnace core tube, which is not preferable. If it exceeds 70 degrees, air is sucked into the furnace core tube, which is decompressed from the dividing surface, and the pressure in the apparatus increases, resulting in a decrease in the collection efficiency of fine particles, deposition in the furnace core tube, and the production efficiency. Since it falls, it is not preferable. Moreover, in the case of 90 degree | times, the crack and crack of a furnace core tube cannot be prevented.

炉芯管の材質は、ムライト、アルミナ、窒化珪素等のセラミックスを使用することができる。   As the material of the furnace core tube, ceramics such as mullite, alumina, and silicon nitride can be used.

図2には、炉芯管を2分割した本発明熱分解装置の全体像を示す。図3は、炉芯管を2分割した加熱炉を示す。図4は、従来の炉芯管を備えた加熱炉を示す。
炉芯管の上部には、原料溶液を噴霧するためのノズルを有し、炉芯管の下部には、製造された微粒子の捕集装置を備える。炉芯管の外周部には加熱源であるヒーターを備えている。この炉芯管とヒーターとを併せて加熱炉を構成している。
In FIG. 2, the whole image of the thermal decomposition apparatus of this invention which divided | segmented the furnace core tube into 2 is shown. FIG. 3 shows a heating furnace in which the furnace core tube is divided into two parts. FIG. 4 shows a heating furnace provided with a conventional furnace core tube.
The upper part of the furnace core tube has a nozzle for spraying the raw material solution, and the lower part of the furnace core tube is provided with a device for collecting the produced fine particles. A heater as a heating source is provided on the outer peripheral portion of the furnace core tube. The furnace core tube and the heater together constitute a heating furnace.

本発明の微粒子製造装置においては、図2のように、原料溶液を乾燥ゾーン及び加熱ゾーンを有する縦型の噴霧熱分解装置の上部から噴霧し、乾燥及び熱分解させる。すなわち、原料溶液を噴霧熱分解装置の入り口から噴霧し、乾燥させて、前記原料溶液の噴霧液滴を形成し、当該液滴から溶媒を除去する。   In the fine particle production apparatus of the present invention, as shown in FIG. 2, the raw material solution is sprayed from the upper part of a vertical spray pyrolysis apparatus having a drying zone and a heating zone, and dried and pyrolyzed. That is, the raw material solution is sprayed from the inlet of the spray pyrolysis apparatus and dried to form spray droplets of the raw material solution, and the solvent is removed from the droplets.

前記原料溶液の噴霧には、超音波式の噴霧装置、流体ノズルによる噴霧装置など一般的な液滴を形成する装置を使用することができる。生産性の観点から、流体ノズルによる噴霧装置を使用するのが好ましく、具体的には、2流体ノズルや4流体ノズルで噴霧するのが、粒子径の調整、生産性の点で好ましい。ここで2流体ノズルの方式には、空気と前記溶液とをノズル内部で混合する内部混合方式と、ノズル外部で空気と前記溶液を混合する外部混合方式があるが、いずれも採用できる。   For spraying the raw material solution, a general apparatus for forming droplets such as an ultrasonic spray apparatus or a spray apparatus using a fluid nozzle can be used. From the viewpoint of productivity, it is preferable to use a spray device using a fluid nozzle. Specifically, spraying with a two-fluid nozzle or four-fluid nozzle is preferable in terms of particle diameter adjustment and productivity. Here, the two-fluid nozzle method includes an internal mixing method in which air and the solution are mixed inside the nozzle, and an external mixing method in which the air and the solution are mixed outside the nozzle.

噴霧される液滴の平均粒子径は、ノズル径や空気の圧力によって調整することができ、0.5〜150μmが好ましく、1〜100μmがより好ましく、1〜50μmがさらに好ましい。   The average particle diameter of the sprayed droplets can be adjusted by the nozzle diameter and the air pressure, preferably 0.5 to 150 μm, more preferably 1 to 100 μm, and further preferably 1 to 50 μm.

原料溶液としては、目的の微小粒子を構成する元素を含有する溶液が挙げられ、目的の微小粒子が無機酸化物微小粒子の場合、無機酸化物微小粒子を構成する元素を含有する溶液が好ましく、水等の溶媒に溶解する化合物がより好ましい。そのような化合物としては、無機塩、金属アルコキシド等が挙げられる。より具体的には、アルミニウム塩、チタン塩、マグネシウム塩、アルミノケイ酸塩、アルミニウムアルコキシド、テトラエトキシシラン、テトラメトキシシラン等が挙げられる。また、アルミニウム酸化物、ケイ素酸化物を溶媒に分散した溶液、アルミニウム酸化物、ケイ素酸化物のゾル溶液も原料溶液として用いることができる。さらに、溶融温度、耐熱性、粒子強度を調整するために他の元素の原料を添加することもできる。また、これらの原料化合物から得られる酸化物としては、無機酸化物、例えば金属酸化物、アルミナ、シリカ、アルミニウムおよびケイ素からなる酸化物などが挙げられ、より具体的には、アルミナ、シリカ、アルミニウムおよびケイ素からなる酸化物、チタン酸化物、マグネシウム酸化物、ジルコニウム酸化物、バリウム酸化物、セリウム酸化物、イットリウム酸化物などが挙げられ、これら酸化物を組み合わせた複合酸化物も挙げられる。   Examples of the raw material solution include a solution containing an element constituting the target microparticle. When the target microparticle is an inorganic oxide microparticle, a solution containing the element constituting the inorganic oxide microparticle is preferable. A compound that is soluble in a solvent such as water is more preferred. Examples of such compounds include inorganic salts and metal alkoxides. More specifically, aluminum salts, titanium salts, magnesium salts, aluminosilicates, aluminum alkoxides, tetraethoxysilane, tetramethoxysilane and the like can be mentioned. A solution in which aluminum oxide or silicon oxide is dispersed in a solvent, or a sol solution of aluminum oxide or silicon oxide can also be used as a raw material solution. Furthermore, raw materials of other elements can be added to adjust the melting temperature, heat resistance, and particle strength. Examples of the oxides obtained from these raw material compounds include inorganic oxides such as metal oxides, aluminas, silicas, aluminums and silicon oxides, and more specifically, aluminas, silicas, aluminums. And oxides composed of silicon, titanium oxide, magnesium oxide, zirconium oxide, barium oxide, cerium oxide, yttrium oxide, and the like, and composite oxides combining these oxides are also included.

これらの酸化物を構成する元素の原料を溶解あるいは分散する溶媒としては、水及び有機溶媒が挙げられるが、環境への影響、製造コストの点から水が好ましい。
原料溶液中の酸化物を構成する元素の原料濃度は、得られる酸化物粒子の密度、強度等を考慮し、0.01mol/L〜飽和濃度が好ましく、0.1mol/L〜2.0mol/Lがより好ましい。なお、元素の原料濃度を高くすれば、得られる酸化物粒子の粒子径が大きくなるため、粒子径の大きい粒子を得るためには元素濃度を0.3〜1.5mol/Lとするのが好ましい。
噴霧した原料溶液の液滴を加熱炉に設置された炉芯管内にて乾燥及び熱分解を行う。
乾燥工程は、前記原料溶液の噴霧液滴から溶媒を除去する乾燥工程であり、ここでは、噴霧液滴粒子から溶媒が蒸発し、液滴粒子表面に無機塩が析出し、粒子内部に空隙が形成される。この乾燥工程の温度は、用いる原料溶液の噴霧液滴から、溶媒が蒸発する温度であればよいが、乾燥工程で無機塩が析出する必要性から、室温〜600℃の範囲内であって0.1秒から1分程度で当該蒸発及び析出が生じる温度であるのが好ましい。より好ましくは100℃〜600℃であり、さらに好ましくは150℃〜500℃であり、さらに好ましくは150〜450℃である。
Examples of the solvent that dissolves or disperses the raw materials of the elements constituting these oxides include water and organic solvents, but water is preferable from the viewpoint of environmental impact and production cost.
The raw material concentration of the element constituting the oxide in the raw material solution is preferably from 0.01 mol / L to a saturated concentration, taking into account the density and strength of the resulting oxide particles, and preferably from 0.1 mol / L to 2.0 mol / L is more preferable. In addition, since the particle diameter of the oxide particle obtained will become large if the raw material density | concentration of an element is made high, in order to obtain a particle with a large particle diameter, it is 0.3-1.5 mol / L of element concentration preferable.
The sprayed raw material solution droplets are dried and pyrolyzed in a furnace core tube installed in a heating furnace.
The drying step is a drying step for removing the solvent from the spray droplets of the raw material solution. Here, the solvent evaporates from the spray droplet particles, an inorganic salt is deposited on the surface of the droplet particles, and voids are formed inside the particles. It is formed. The temperature of this drying step may be any temperature at which the solvent evaporates from the spray droplets of the raw material solution to be used, but is within the range of room temperature to 600 ° C. and 0 because of the necessity of depositing inorganic salts in the drying step. It is preferably a temperature at which the evaporation and precipitation occur in about 1 second to 1 minute. More preferably, it is 100 degreeC-600 degreeC, More preferably, it is 150 degreeC-500 degreeC, More preferably, it is 150-450 degreeC.

次に、乾燥された粒子は、加熱され熱分解される。この熱分解工程は、乾燥された液滴および粒子を熱分解して酸化物粒子を形成する工程であり、ここでは、液滴および粒子表面の無機塩が熱分解および酸化されて酸化物粒子が生成する。この熱分解工程の温度は、前記熱分解および酸化反応が進行する温度であればよいが、熱分解工程で酸化反応が終了する必要性から、150℃〜1200℃が好ましい。また0.1秒〜1分程度で当該酸化反応が終了する温度が好ましく、具体的には、400℃〜1200℃が好ましく、500℃〜1200℃が好ましい。
また、本発明装置においては、微小粒子として中空粒子も製造することができる。中空粒子を製造する場合、酸化物粒子の表面を溶融し、粒子強度の高い中空粒子を得るため、熱分解工程後に、粒子の外殻表面の孔を閉塞させて、さらに溶融工程を行うのが好ましい。溶融工程は、形成された酸化物粒子の表面を溶融する工程であり、酸化物粒子の表面を溶融し、表面に存在する孔を閉塞させる工程である。この溶融工程の温度は、酸化物粒子の表面が溶融する温度であればよいが、溶融工程で溶融により酸化物粒子表面の孔が閉塞する点から600℃以上が好ましい。また、0.1秒〜1分程度で酸化物粒子表面が溶融する点から、700℃以上が好ましく、800℃以上がより好ましく、900℃以上がさらに好ましく、1200℃以上がさらに好ましい。なお、経済性の点から1500℃以下が好ましい。また、溶融温度が600〜1200℃と低い酸化物であれば、熱分解ゾーンと溶融ゾーンの加熱温度を同じにしてもよい。
The dried particles are then heated and pyrolyzed. This pyrolysis step is a step of thermally decomposing dried droplets and particles to form oxide particles. Here, the inorganic salts on the droplets and the surface of the particles are pyrolyzed and oxidized to form oxide particles. Generate. Although the temperature of this thermal decomposition process should just be the temperature which the said thermal decomposition and oxidation reaction advance, 150 to 1200 degreeC is preferable from the necessity for an oxidation reaction being complete | finished in a thermal decomposition process. Moreover, the temperature which the said oxidation reaction complete | finishes in about 0.1 second-about 1 minute is preferable, and 400 degreeC-1200 degreeC is specifically preferable, and 500 degreeC-1200 degreeC is preferable.
In the device of the present invention, hollow particles can also be produced as fine particles. When producing hollow particles, the surface of the oxide particles is melted to obtain hollow particles with high particle strength. After the pyrolysis step, the pores on the outer shell surface of the particles are closed and the melting step is further performed. preferable. The melting step is a step of melting the surface of the formed oxide particles, and is a step of melting the surface of the oxide particles and closing the pores existing on the surface. The temperature of the melting step may be any temperature at which the surface of the oxide particles melts, but is preferably 600 ° C. or higher from the viewpoint that the pores on the surface of the oxide particles are blocked by melting in the melting step. Moreover, from the point which the oxide particle surface fuse | melts in about 0.1 second-1 minute, 700 degreeC or more is preferable, 800 degreeC or more is more preferable, 900 degreeC or more is more preferable, 1200 degreeC or more is further more preferable. In addition, from the point of economical efficiency, 1500 degrees C or less is preferable. If the melting temperature is as low as 600 to 1200 ° C., the heating temperature of the thermal decomposition zone and the melting zone may be the same.

溶融工程が終了した酸化物中空粒子は、表面の孔が閉塞されていることから外殻に孔がなく、粒子強度の高い酸化物中空粒子となっている。
熱分解工程、更に必要により溶融工程を行った酸化物中空粒子を冷却後回収すれば、目的の酸化物中空粒子が得られる。酸化物中空粒子の回収は、高性能サイクロン粉体回収機やバグフィルターを用いた粉体回収装置を用いることができる。また、酸化物中空粒子の回収にあたっては、フィルターを通過させることにより粒子径の調整をすることができる。
本発明装置により得られる酸化物粒子の好ましい例としては、中空室を区画する殻を有する酸化物中空粒子であって、形状がほぼ球状(平均円形度0.85以上)、平均粒子径が0.5μm〜100μm、前記殻の厚みが4500nm以下のものが挙げられる。
ここで、円形度は、走査型電子顕微鏡写真から粒子の投影面積(A)と周囲長(PM)を測定し、周囲長(PM)に対する真円の面積を(B)とすると、その粒子の円形度はA/Bとして表される。そこで、試料粒子の周囲長(PM)と同一の周囲長を持つ真円の周囲長および面積は、それぞれPM=2πr、B=πr2であるから、B=π×(PM/2π)2となり、この粒子の円形度は、円形度=A/B=A×4π/(PM)2として算出される。100個の粒子について円形度を測定し、その平均値でもって平均円形度とする。なお、本発明の酸化物中空粒子は、各種フィラーとして混合したときの分散性、混合性など点から、平均円形度は、0.85以上、好ましくは0.90以上である。
The oxide hollow particles that have undergone the melting step are oxide hollow particles that have no pores in the outer shell and have high particle strength because the pores on the surface are closed.
If the oxide hollow particles subjected to the pyrolysis step and, if necessary, the melting step are recovered after cooling, the desired oxide hollow particles are obtained. The oxide hollow particles can be collected by using a high-performance cyclone powder collecting machine or a powder collecting apparatus using a bag filter. Further, in collecting the oxide hollow particles, the particle diameter can be adjusted by passing through a filter.
Preferable examples of the oxide particles obtained by the apparatus of the present invention are oxide hollow particles having shells that define a hollow chamber, and have a substantially spherical shape (average circularity of 0.85 or more) and an average particle size of 0. 0.5 μm to 100 μm, and the thickness of the shell is 4500 nm or less.
Here, the circularity is determined by measuring the projected area (A) and the perimeter (PM) of a particle from a scanning electron micrograph, and assuming that the area of a perfect circle with respect to the perimeter (PM) is (B). Circularity is expressed as A / B. Therefore, the circumference and area of a perfect circle having the same circumference as the sample particle (PM) are PM = 2πr and B = πr 2 , respectively, so that B = π × (PM / 2π) 2 . The circularity of the particles is calculated as circularity = A / B = A × 4π / (PM) 2 . The circularity is measured for 100 particles, and the average value is defined as the average circularity. The oxide hollow particles of the present invention have an average circularity of 0.85 or more, preferably 0.90 or more from the viewpoint of dispersibility and mixing properties when mixed as various fillers.

本発明装置で得られる酸化物中空粒子の平均粒子径は、0.5μm〜100μmであり、好ましくは1μm〜50μmであり、より好ましくは2μm〜30μmであり、さらに好ましくは2μm〜20μmであり、さらに好ましくは2μm〜10μmである。100μmを超える場合は一部が円形度の小さい球となることがあり、好ましくない。なお、平均粒子径の調整は、噴霧に使用する流体ノズルの直径および圧縮空気の圧力の調節によって行うことができる。ここで粒子径は、電子顕微鏡の解析によって測定でき、その平均は、JIS R 1629「ファインセラミックス原料のレーザ回折・散乱法による粒子径分布測定方法」、レーザー回折・散乱法による粒子径分布測定装置として、例えばマイクロトラック(日機装株式会社製)などによって計算できる。
本発明装置で得られる酸化物中空粒子の粒子径分布(粒度分布)は、せまい程好ましく、粒子の80%以上が平均粒子径の±5.0μmにあるのが好ましく、粒子の80%以上が平均粒子径の±4.5μmにあるのがより好ましく、粒子の80%以上が平均粒子径の±4.0μmにあるのがさらに好ましい。
本発明方法で得られる酸化物中空粒子の殻の厚みは、4500nm以下であり、1〜2000nmが好ましく、10〜500nmがより好ましく、50〜350nmがさらに好ましい。殻の厚みが4500nmを超えると、中空室が十分でなく、熱伝導率が十分に小さい粒子とならない。また、殻の厚みが小さすぎる場合には、粒子の強度が十分でない可能性がある。殻の厚みは透過型電子顕微鏡(TEM)像から測定できる。
The average particle diameter of the oxide hollow particles obtained by the device of the present invention is 0.5 μm to 100 μm, preferably 1 μm to 50 μm, more preferably 2 μm to 30 μm, still more preferably 2 μm to 20 μm, More preferably, it is 2 micrometers-10 micrometers. When it exceeds 100 μm, a part of the sphere may be a sphere having a small circularity, which is not preferable. The average particle diameter can be adjusted by adjusting the diameter of the fluid nozzle used for spraying and the pressure of the compressed air. Here, the particle size can be measured by analysis with an electron microscope, and the average is JIS R 1629 “Method for measuring particle size distribution by laser diffraction / scattering method of fine ceramic raw material”, Particle size distribution measuring device by laser diffraction / scattering method For example, it can be calculated by a micro truck (manufactured by Nikkiso Co., Ltd.).
The particle size distribution (particle size distribution) of the oxide hollow particles obtained by the device of the present invention is preferably as narrow as possible, and 80% or more of the particles are preferably within ± 5.0 μm of the average particle size, and 80% or more of the particles are The average particle diameter is more preferably ± 4.5 μm, and more preferably 80% or more of the particles are in the average particle diameter of ± 4.0 μm.
The thickness of the oxide hollow particle shell obtained by the method of the present invention is 4500 nm or less, preferably 1 to 2000 nm, more preferably 10 to 500 nm, and still more preferably 50 to 350 nm. When the thickness of the shell exceeds 4500 nm, the hollow chamber is not sufficient, and particles having a sufficiently low thermal conductivity are not obtained. If the shell thickness is too small, the strength of the particles may not be sufficient. The thickness of the shell can be measured from a transmission electron microscope (TEM) image.

本発明の装置によれば、耐熱性、耐薬品性に優れたセラミック製の炉芯管の亀裂や割れを防止できるため、安定した微粒子の製造及び不純物の混入がない均一な高品質の微小粒子が高収率で得ることができる。   According to the apparatus of the present invention, since cracks and cracks in a ceramic furnace core tube excellent in heat resistance and chemical resistance can be prevented, stable fine particle production and uniform high quality fine particles free from impurities Can be obtained in high yield.

次に実施例を挙げて本発明を更に詳細に説明する。   EXAMPLES Next, an Example is given and this invention is demonstrated still in detail.

(実施例1)
図1に示す2分割され、接触面が45度のムライト製の炉芯管を組合わせて、図2に示すように加熱炉とした。炉芯管は、加熱炉の上部と下部で固定し、炉芯管同士を密着させ、原料やガスの漏れがないようにした。炉芯管の大きさは、直径220mm、厚み10mm、長さ600mmとした。
ノズルユニットを炉芯管に設置した。次いで蒸留水1リットルに硝酸アルミニウムを0.04mol、オルトケイ酸テトラエチルを0.16mol溶解したアルミニウム及びケイ素の混合水溶液を溶液タンクに投入した。投入された水溶液は送液ポンプにより、2流体ノズルを介してミスト状に噴霧され、乾燥ゾーン(約400℃)、次いで熱分解ゾーン(1000℃)を通過させた。ポンプの吸引を一定とし、装置の圧力計により、炉芯管内の圧力の変化を確認した。
装置の圧力計の変化はなく、炉芯管内の圧力は一定であり、炉芯管が外部の空気を吸引していないことを確認した。
8時間後、噴霧、加熱を停止し、冷却後、炉芯管の状態を確認した。試験後、炉芯管に亀裂や割れなどは確認されなかった。
Example 1
A furnace core tube made of mullite divided into two parts as shown in FIG. 1 and having a contact surface of 45 degrees was combined to form a heating furnace as shown in FIG. The furnace core tubes were fixed at the upper and lower parts of the heating furnace, and the furnace core tubes were brought into close contact with each other so that no leakage of raw materials or gases occurred. The size of the furnace core tube was 220 mm in diameter, 10 mm in thickness, and 600 mm in length.
A nozzle unit was installed in the furnace core tube. Next, a mixed aqueous solution of aluminum and silicon in which 0.04 mol of aluminum nitrate and 0.16 mol of tetraethyl orthosilicate were dissolved in 1 liter of distilled water was charged into the solution tank. The introduced aqueous solution was sprayed in a mist form by a liquid feed pump through a two-fluid nozzle, and passed through a drying zone (about 400 ° C.) and then a thermal decomposition zone (1000 ° C.). The pump suction was kept constant, and the pressure change in the furnace core tube was confirmed by the pressure gauge of the device.
There was no change in the pressure gauge of the apparatus, the pressure in the furnace core tube was constant, and it was confirmed that the furnace core tube was not sucking outside air.
After 8 hours, spraying and heating were stopped, and after cooling, the state of the furnace core tube was confirmed. After the test, no cracks or cracks were found in the furnace core tube.

(実施例2)
2分割され、接触面が70度のムライト製の炉芯管を使用し、以下実施例1と同様に行った。
装置の圧力計の変化はなく、炉芯管内の圧力は一定であり、炉芯管が外部の空気を吸引していないことを確認した。
8時間後、噴霧、加熱を停止し、冷却後、炉芯管の状態を確認した。試験後、炉芯管に亀裂や割れなどは確認されなかった。
(Example 2)
A furnace core tube made of mullite having two contact surfaces and a contact surface of 70 degrees was used, and the same procedure as in Example 1 was performed.
There was no change in the pressure gauge of the apparatus, the pressure in the furnace core tube was constant, and it was confirmed that the furnace core tube was not sucking outside air.
After 8 hours, spraying and heating were stopped, and after cooling, the state of the furnace core tube was confirmed. After the test, no cracks or cracks were found in the furnace core tube.

(比較例1)
図4に示すように円筒状のムライト製の炉芯管を使用し、以下実施例1と同じとした。
ポンプの吸引を一定にしていたが、装置の圧力計が大きくなり、炉芯管が外部の空気を吸引していることを確認した。
8時間後、噴霧、加熱を停止し、冷却後、炉芯管の状態を確認した。試験後、炉芯管が割れていることを確認した。
(Comparative Example 1)
A cylindrical mullite furnace core tube was used as shown in FIG.
Although the pump suction was kept constant, it was confirmed that the pressure gauge of the device became large and the furnace core tube was sucking outside air.
After 8 hours, spraying and heating were stopped, and after cooling, the state of the furnace core tube was confirmed. After the test, it was confirmed that the furnace core tube was cracked.

(比較例2)
2分割され、接触面が90度のムライト製の炉芯管を使用し、以下実施例1と同様に行った。
ポンプの吸引を一定にしていたが、装置の圧力計が大きくなり、炉芯管が外部の空気を吸引していることを確認した。
8時間後、噴霧、加熱を停止し、冷却後、炉芯管の状態を確認した。試験後、炉芯管に亀裂や割れなどは確認されなかった。
(Comparative Example 2)
Using a mullite furnace core tube divided into two and having a contact surface of 90 degrees, the same procedure as in Example 1 was performed.
Although the pump suction was kept constant, it was confirmed that the pressure gauge of the device became large and the furnace core tube was sucking outside air.
After 8 hours, spraying and heating were stopped, and after cooling, the state of the furnace core tube was confirmed. After the test, no cracks or cracks were found in the furnace core tube.

Claims (1)

原料溶液を乾燥ゾーン及び加熱ゾーンを有する噴霧熱分解装置に噴霧し、乾燥及び熱分解させる微小粒子の製造装置であって、加熱炉の炉芯管が、長手方向に2以上に直線状に分割され、該分割面は圧着され、該分割面が炉芯管の上端面の弧上接線に対して45度以上70度以下の角度であるセラミック製炉芯管であることを特徴とする熱分解による微小粒子の製造装置。   A device for producing fine particles in which a raw material solution is sprayed on a spray pyrolysis apparatus having a drying zone and a heating zone, and dried and pyrolyzed. The furnace core tube is divided into two or more in the longitudinal direction linearly. And the split surface is a ceramic furnace core tube having an angle of not less than 45 degrees and not more than 70 degrees with respect to the arc tangent of the upper end surface of the furnace core pipe. Production equipment for fine particles.
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6018496U (en) * 1983-07-15 1985-02-07 石川島播磨重工業株式会社 radiation tube
JPH1177635A (en) * 1997-09-03 1999-03-23 Ngk Spark Plug Co Ltd Production of hollow ceramic sintered object
WO2000078672A1 (en) * 1999-06-22 2000-12-28 Merck Patent Gmbh Spray pyrolysis or spray drying method and facility for the implementation thereof
JP2010208917A (en) * 2009-03-12 2010-09-24 Ohkawara Kakohki Co Ltd Method and device for pulse spray thermal decomposition
JP2015229622A (en) * 2014-06-06 2015-12-21 太平洋セメント株式会社 Production apparatus of hollow particle

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6018496U (en) * 1983-07-15 1985-02-07 石川島播磨重工業株式会社 radiation tube
JPH1177635A (en) * 1997-09-03 1999-03-23 Ngk Spark Plug Co Ltd Production of hollow ceramic sintered object
WO2000078672A1 (en) * 1999-06-22 2000-12-28 Merck Patent Gmbh Spray pyrolysis or spray drying method and facility for the implementation thereof
JP2003502264A (en) * 1999-06-22 2003-01-21 メルク パテント ゲゼルシャフト ミット ベシュレンクテル ハフトング Spray pyrolysis or spray drying process and plant for performing it
JP2010208917A (en) * 2009-03-12 2010-09-24 Ohkawara Kakohki Co Ltd Method and device for pulse spray thermal decomposition
JP2015229622A (en) * 2014-06-06 2015-12-21 太平洋セメント株式会社 Production apparatus of hollow particle

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