JP2946231B2 - Ultra fine powder classifier - Google Patents

Description

【発明の詳細な説明】 ［産業上の利用分野］ 本願発明は、ニューセラミックスをはじめ最新の微粉
材料を取扱う上で必須の超微粉分級機に係る。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an ultrafine powder classifier essential for handling the latest fine powder materials including new ceramics.

［従来の技術］ 粒径がまちまちの粗粒と微粉の入り混った混合粉粒体
を、粒径ごとに分離して所望の粒径のみの微粉を精度高
く取り出すことは、ニューセラミックスの製造をはじ
め、広範な分野において求められる技術である。[Prior art] Separating mixed powders containing a mixture of coarse particles and fine powders having different particle diameters for each particle diameter and taking out a fine powder having only a desired particle diameter with high precision is a manufacturing method of new ceramics. This is a technology that is required in a wide range of fields.

このため粉粒体のふくまれる固液混合のスラリーや、
含塵気流を処理して固体分のみを分離回収するために数
多くの研究や開発が進められてきた。For this reason, solid-liquid mixed slurries containing powder and granules,
Numerous studies and developments have been made to treat dust-containing airflows to separate and recover only solids.

粉粒体を含む気流を急激に方向転換させ慣性力を利用
して微粉を分級する方式を慣性分級と呼び、その一例と
して特開昭55−167072号公報・第４図を説明する。A method of classifying fine powder using an inertial force by rapidly changing the direction of an air flow containing powders and granules is referred to as inertial classification, and an example of such a method will be described in Japanese Patent Application Laid-Open No. Sho 55-167072 / FIG.

図において密閉容器100内において容器内の空気を吸
引して負圧とし、この中で固気混合の気流を流す管路10
1を開口してノズル102を形成すると、微粉Faのみノズル
から吸引して管路外へ案内され、粗粒Gaは慣性によって
そのまま管路を通り抜けて行くことによって粗細分級を
しようとするものである。In the figure, a line 10 through which air in a container is sucked into a negative pressure in a closed container 100 to make a
When the nozzle 102 is formed by opening 1, only the fine powder Fa is sucked from the nozzle and guided to the outside of the pipe, and the coarse particles Ga are intended to be coarsely and finely classified by passing through the pipe as it is by inertia. .

気流を旋回させて遠心力を働かせ粉体のみを分離回収
する自由渦型は、集塵機のサイクロンとして広く慣用さ
れ、分離の効果を向上するために多くの提案もある（例
えば特開昭59−49817号公報・第５図）。The free vortex type, in which only the powder is separated and collected by turning the airflow to exert centrifugal force to act, is widely used as a cyclone of a dust collector, and there are many proposals for improving the effect of separation (for example, Japanese Patent Application Laid-Open No. 59-49817). No., FIG. 5).

一方、固液混合のスラリーを処理して遠心力の場にお
いて所望の粒径以下の微粉だけを回収しようとする回分
式遠心分離機もある（例えば特開昭63−224752号公報・
第６図）。On the other hand, there is a batch type centrifugal separator which processes a slurry of a solid-liquid mixture to collect only fine powder having a desired particle size or less in a centrifugal force field (for example, Japanese Patent Application Laid-Open No. 63-224752).
(Fig. 6).

図において固定ケーシング103内に回転軸104に保持さ
れた円筒形回転ボウル105を高速回転する構成になって
いる。材料のスラリーは回転ボウルの内側下方部の供給
口106から供給され、回転による遠心力によって分級さ
れて、微粉と液のみが回転ボウルの上方にある取出口10
7より取出して回収される。この発明の要旨は供給され
たスラリーが余りに早く取出口へ達して分級作用がきわ
めて不十分なので、スラリーの流れ方向に交差する様に
もぐり堰108も設けたことを特徴に謳っている。In the figure, a cylindrical rotary bowl 105 held by a rotary shaft 104 in a fixed casing 103 is rotated at a high speed. The slurry of the material is supplied from a supply port 106 at the lower portion inside the rotating bowl, and is classified by centrifugal force due to rotation, so that only fine powder and liquid are taken out of the outlet 10 above the rotating bowl.
Removed from 7 and collected. The gist of the present invention is characterized in that the supplied slurry arrives at the outlet too early and the classifying action is extremely insufficient, so that the boring 108 is provided so as to cross the flow direction of the slurry.

［発明が解決しようとする課題］ 最初に掲げた従来技術である慣性力方式は分離力が弱
く、密閉器内の開口部（ノズル）においてのみ瞬間的に
作用するものであるから、余程強力な吸引力を以ってし
ても効率的にはきわめて低いレベルにあると言わざるを
得ない。旋回流による遠心力を利用する方式は本来固体
（粉塵）と気体とを分離するのが使命であり、粉粒体を
さらに粒径別に分離回収するためには、強力な気流速度
と広大な分離室とを必要とするであろうから、設備面積
やその費用から見て到底採用し難いと考えられる。[Problem to be Solved by the Invention] The inertia force method, which is the first prior art, has a weak separation force and acts instantaneously only at the opening (nozzle) in the enclosure. It must be said that even with a large suction force, the efficiency is extremely low. The method of using centrifugal force due to swirling flow is originally intended to separate solids (dust) and gas, and in order to separate and collect powders by particle size further, strong airflow velocity and vast separation It will probably require a room, so it is considered difficult to adopt it in terms of the equipment area and its cost.

スラリーの湿式分級は回転ボウル中の遠心力の差を利
用するもので、遠心分離機の典型的な方式である。この
方式については所定の粒径以上の粒子の沈降速度を遠心
力で高めて短時間に沈澱物層Gbへ沈積させ、微粒子層ス
ラリーFbを分級回収するのであるが、沈澱物層へ行かず
微粒子層スラリー内に残るのはストークスの抵抗式によ
って理論上決定できるが、この式が適用できるのはきわ
めて濃度の小さなスラリーに留まるので非工業的であ
り、実際の生産レベルにあっては回転ボウル内のスラリ
ーは操作中にデッドストックとして滞留して了うので、
後から供給されても、スラリーの平衡液面上を上滑りに
短絡して分級の余地がきわめて小さいと考えられる。こ
のような短絡を防止するために、もぐり堰108を設けて
供給スラリーの回転ボウル内で滞留時間を延長して遠心
力の場に留め、分級精度を高めて行こうとするのである
が、連続的に操作をする限り、回転ボウルの内壁に添着
する沈澱層の層厚は肥大するばかりだから、遠心力の強
さは減退する方向にあり、分級の精度は次第に低下する
と言っても差支えないいのではないか。その他回転体中
の遠心力の場を利用する方式では常に分級の継続が精度
の劣化を誘発するという課題がつきまとう。Wet classification of slurry utilizes a difference in centrifugal force in a rotating bowl, and is a typical type of centrifugal separator. In this method, the sedimentation speed of particles having a predetermined particle size or more is increased by centrifugal force to deposit the particles in the sediment layer Gb in a short time, and the fine particle layer slurry Fb is classified and collected. What remains in the bed slurry can be determined theoretically by Stokes's resistance formula, but this formula is applicable only to very low concentration slurries and is non-industrial, and at actual production levels, Of the slurry will remain as dead stock during the operation,
Even if it is supplied later, it is considered that there is very little room for classification due to short-circuiting on the equilibrium liquid level of the slurry by sliding upward. In order to prevent such a short circuit, a boring weir 108 is provided to extend the residence time of the supply slurry in the rotating bowl, to keep it in the place of centrifugal force, and to improve the classification accuracy. As long as the operation is performed properly, the thickness of the sedimentation layer attached to the inner wall of the rotating bowl only increases, so the strength of the centrifugal force tends to decrease, and the accuracy of classification may gradually decrease. Isn't it? In the other method using the centrifugal force field in the rotating body, there is a problem that continuation of classification always causes deterioration of accuracy.

本願発明は以上の課題を解決するために乾式（気
流）、湿式（スラリー）を問わず、精度の高い超微粉分
級を常に持続でき、かつ構成も簡単で保全の容易な超微
粉分級機の提供を目的とする。SUMMARY OF THE INVENTION The present invention provides an ultrafine particle classifier that can always maintain high-precision ultrafine particle classification regardless of a dry type (air flow) or a wet type (slurry) and has a simple configuration and easy maintenance. With the goal.

［課題を解決するための手段］ 本願発明に係る超微粉分級機は、回転軸線の一方を被
分級材料の供給口、他方を微粉の排出口とし、両者を始
端と終端として断面が円環状又は軸線に対して対称的な
同一円周上に均等割り付けされて配置されている複数個
の同一形状の回転自在の環状管路の中途に少くとも一周
の粗粒排出口を開口し、開口部からの残り環状管路は外
周と軸線の距離を順次縮小して終端に至ることによって
前記の課題を解決した。[Means for Solving the Problems] The ultra-fine powder classifier according to the present invention has one of the rotation axes as a supply port for the material to be classified and the other as a discharge port for fine powder, and has a circular or circular cross section with both starting and end points. Open at least one round of coarse particle discharge port in the middle of a plurality of rotatable annular pipes of the same shape that are equally allocated on the same circumference symmetrical with respect to the axis. The above-mentioned problem has been solved by sequentially reducing the distance between the outer circumference and the axis to reach the end of the remaining annular conduit.

［作用・実施例］ 第１図は本願実施例の垂直断面図、第２図イ，ロ，ハ
は第１図のＡ−Ａ′断面における種々の態様を示したも
のである。[Operations and Embodiments] FIG. 1 is a vertical sectional view of an embodiment of the present invention, and FIGS. 2A, 2B, and 3C show various aspects in the AA 'section of FIG.

超微粉分級機は回転自在に軸支された環状管路２を主
体とし、管路の一端が被分級材Ｓの供給口３であり、他
端が微粉Ｆの排出口４であって、この両口を始端と終端
としてリング状の管路を形成し、全体が軸線Ｃの周囲を
回転する、この環状管路２の実施の一例としては第１図
のようにフィールド競技のトラック様の長円形がよい
が、規則的な多角形でもよく、また軸線Ｃと直角に截っ
たＡ−Ａ′断面は第２図イのようにドーナツ様の円環で
あるのが、分級有効空間が広くかつ均等で望ましい。し
かし第２図ロ，ハに示すように第一例の一部だけを切り
取った断面で形成することも可能であり、断面は種々の
態様が適用できる。環状管路２の中途点に少くとも一周
の開口部を設け、これが粗粒Ｇの排出口５を形成する。The ultra-fine powder classifier is mainly composed of an annular pipeline 2 rotatably supported, one end of the pipeline being a supply port 3 for the material S to be classified, and the other end being a discharge port 4 of the fine powder F. A ring-shaped pipe is formed with both mouths as a starting end and a terminating end, and the entire pipe rotates around an axis C. As an example of the implementation of the annular pipe 2, as shown in FIG. Although a circular shape is preferable, a regular polygonal shape may be used. The AA 'section cut at right angles to the axis C is a donut-like ring as shown in FIG. And even and desirable. However, as shown in FIGS. 2 (b) and 2 (c), it is also possible to form a cross section in which only a part of the first example is cut out, and various cross sections can be applied. At least one round of an opening is provided at a middle point of the annular pipe 2, and this forms an outlet 5 for the coarse particles G.

この排出口５以後の環状管路２の外周と軸線Ｃとの距
離は順次縮小する。順次と言う意味は第３図に示す第三
実施例のように、粗粒Ｇの排出口５が一組ではなく二組
5A,5B設定されているときにはその都度段階的と言う状
態を指す。The distance between the outer periphery of the annular conduit 2 after the discharge port 5 and the axis C gradually decreases. The meaning of “sequential” means that, as in the third embodiment shown in FIG.
When 5A and 5B are set, it indicates a state that is stepwise each time.

本願発明の構成は以上のような形状、組合せよりなる
から、どのような態様であれ、基本的な作用としては、
不揃いな粗粒Ｇと微粉Ｆを不規則に混じて流動可能にし
た含塵気流、又はスラリー（泥漿）を高速回転中の超微
粉分級機１の供給口３から連続的に供給すると、粒子に
は遠心力が作用するが、その他に摩擦抵抗力や流体の浮
力などが相互に影響を及ぼし合って複雑な力を合成し、
結局粒径が大きく単重量も大きく、比表面積の小さい粗
粒ほど早く環状管路の外周側へ押しやられ、一方管路の
外壁面については粒子の濃度の増加につれて、反対側へ
粒子を拡散しようとするが、ここでも粒径の小さい微粉
ほど拡散しようとする作用が強く働く。Since the configuration of the present invention consists of the shapes and combinations as described above, in any mode, as a basic operation,
When the dust-containing gas stream or the slurry (slurry) made to flow by irregularly mixing the coarse particles G and the fine particles F is continuously supplied from the supply port 3 of the ultrafine classifier 1 rotating at a high speed, the particles become Centrifugal force acts, but in addition, frictional resistance and buoyancy of the fluid affect each other and synthesize complex forces,
Eventually, coarse particles having a large particle size, a large single weight, and a small specific surface area are pushed to the outer peripheral side of the annular conduit faster, while the outer wall surface of the conduit tends to diffuse particles to the opposite side as the particle concentration increases. However, also in this case, the action of diffusing the finer powder with a smaller particle size works more strongly.

したがって回転中の環状管路のどこを截って見ても遠
心方向の粒子移動速度と反対方向への拡散速度の平衡に
よって、管内の断面においては外周側壁に最も粗大な粒
子が集中し、軸線へ近づく程、粒は細かく並び管路の最
内周側は最も微粉体を形成する。流動体が気流のときは
管路の全断面に亘ってこの作用が及び、流動体が固液混
合のスラリー状であるときは普通は管路断面の全域を埋
め切らないが、外周側から内周側へ至る粒度の分布状態
は全く同じ傾向を見せる。Therefore, no matter where you cut the rotating annular pipe, the most coarse particles are concentrated on the outer peripheral side wall in the cross section inside the pipe due to the equilibrium between the particle movement velocity in the centrifugal direction and the diffusion velocity in the opposite direction. As it approaches, the particles are finely arranged and the innermost side of the pipeline forms the finest powder. When the fluid is in the air flow, this effect is exerted over the entire cross section of the pipeline. When the fluid is in the form of a solid-liquid mixed slurry, the entire area of the pipeline cross section is not usually filled, but the inner portion is formed from the outer peripheral side. The distribution of the particle size to the peripheral side shows exactly the same tendency.

管内で同心円的に粒度分布を形成し終った点で、外周
側の粗粒Ｇのみが、全周に亘って開口した排出口５から
強制的に押し出され、外周の縮小された残りの環状管路
内には内周側に残った微粉だけが流下を続け、微粉の排
出口４に至って分級品として回収される。この場合、回
転速度、流体の進行速度、粗粉排出口の大きさ、位置、
個数などを適宜調整することによって被分級材の性状や
目標の分級精度などを十分満たすことができる。At the point where the particle size distribution has been formed concentrically in the pipe, only the outer peripheral coarse particles G are forcibly pushed out from the discharge port 5 opened over the entire circumference, and the remaining annular pipe having the reduced outer circumference is reduced. Only fine powder remaining on the inner peripheral side in the road continues to flow down, reaches the fine powder discharge port 4 and is collected as a classified product. In this case, the rotation speed, the traveling speed of the fluid, the size, position,
By appropriately adjusting the number and the like, the properties of the material to be classified and the target classification accuracy can be sufficiently satisfied.

［発明の効果］ 本願発明に係る超微粉分機は以上に述べた作用に基
き、比較的簡単な構造であるため製作，運転，保全が容
易であるにも拘らず、粗粒を分別して効果的に排出し、
常に精度の高い粒径の揃った微粉だけを分級回収する。
所望の分級精度に対応して粗粒を段階ごとに排除する複
数の段列を連ねることが自由に計画できるし、一旦設置
した後も運転条件や分離板の形状、傾斜などの微調整で
広範に適応できる汎用性も具えている。[Effects of the Invention] The ultrafine powder separator according to the present invention has a relatively simple structure based on the above-described operation, and is easy to manufacture, operate, and maintain. Discharged to
Classify and collect only fine powders with consistently high particle size.
It is possible to freely connect multiple stages to remove coarse particles for each stage according to the desired classification accuracy, and even after installation once, it can be extensively adjusted by fine adjustment of operating conditions, shape of separator, inclination, etc. It also has versatility that can be adapted to.

【図面の簡単な説明】[Brief description of the drawings]

第１図は本願発明の実施例を示す垂直断面図、第２図
イ，ロ，ハは第１図のＡ−Ａ′断面における種々の態様
を示す断面図、第３図は別の実施例の垂直断面図、第４
図から第６図まではそれぞれ別の従来技術を示す垂直断
面図。 １……超微粉分級機、２……環状管路 ３……供給口、４……排出口（微粉） ５……排出口（粗粒）、Ｓ……被分級材 Ｆ……微粉、Ｇ……粗粒、Ｃ……軸線FIG. 1 is a vertical sectional view showing an embodiment of the present invention, FIGS. 2 (a), 2 (b) and 2 (c) are cross-sectional views showing various modes in the AA 'section of FIG. 1, and FIG. 3 is another embodiment. Vertical sectional view of the fourth
FIG. 6 to FIG. 6 are vertical sectional views showing different prior arts. DESCRIPTION OF SYMBOLS 1 ... Ultra fine powder classifier, 2 ... Annular pipe 3 ... Supply port, 4 ... Discharge port (fine powder) 5 ... Discharge port (coarse particles), S ... Classified material F ... Fine powder, G …… coarse grain, C …… axis

───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.⁶，ＤＢ名) B03B 5/00 - 5/74 B07B 7/08 B04B 1/00 - 15/12 ──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int.Cl. ⁶ , DB name) B03B 5/00-5/74 B07B 7/08 B04B 1/00-15/12

Claims (1)

(57)【特許請求の範囲】(57) [Claims] 【請求項１】回転軸線の一方を被分級材料の供給口、他
方を微粉の排出口とし、両者を始端と終端として断面が
円環状又は軸線に対して対称的な同一円周上に均等割り
付けされて配置されている複数個の同一形状の回転自在
の環状管路の中途に少くとも一周の粗粒排出口を開口
し、開口部からの残り環状管路は外周と軸線の距離を順
次縮小して終端に至ることを特徴とする超微粉分級機。1. One of the rotation axes is a supply port of the material to be classified and the other is a discharge port of the fine powder. At least one round of coarse-grain discharge port is opened in the middle of a plurality of rotatable annular pipes of the same shape that are arranged and the remaining annular pipe from the opening gradually reduces the distance between the outer circumference and the axis. An ultra fine powder classifier, which reaches the end.