JP2807841B2 - 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 coarse particles and fine powders having different particle diameters for each particle diameter, and taking out fine powders having only a desired particle diameter with high accuracy is a problem of new ceramics. This technology is required in a wide range of fields, including manufacturing.

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。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通す管路101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。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. In the figure, the air in the container is sucked to a negative pressure in the closed container 100 to form a nozzle 102 by opening a pipe 101 through which a gas flow of the solid-gas mixture flows, and only the fine powder Fa is sucked from the nozzle. The coarse Ga is guided outside the pipe, and passes through the pipe as it is due to inertia to perform coarse and fine classification.

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合に
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）。図において固定ケーシング103内に回転軸1
04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107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。On the other hand, there is a batch type centrifugal separator which processes a slurry of a solid-liquid mixture to recover only fine powder having a desired particle size in the case of centrifugal force (for example, Japanese Patent Application Laid-Open No. 63-224752, FIG. 6). ). In the figure, the rotating shaft 1
The configuration is such that the cylindrical rotary bowl 105 held at 04 rotates at high speed. The slurry of the material is supplied from a supply port 106 at a lower portion inside the rotating bowl, is classified by centrifugal force due to rotation, and only fine powder and liquid are taken out and collected from an outlet 107 above the rotating bowl. 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 utilizing the centrifugal force due to the swirling flow is originally intended to separate the solid (dust) and gas from each other. To separate and collect the powder by particle size, the strong airflow velocity and the 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
めて濃度の小さい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
ーは操作中にデット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
と行っても差支えないのではないか。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 the Stokes' resistance formula, but this formula is applicable only to very low concentration slurries and is non-industrial, and in actual production levels, Slurry stays as debt 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 and to keep it in the place of centrifugal force, so as to increase the classification accuracy. The thickness of the sedimentation layer attached to the inner wall of the rotating bowl only increases as long as the operation is performed properly, so the strength of the centrifugal force tends to decrease, and if the accuracy of classification gradually decreases, it may be possible to perform it. Isn't it? In the 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、回転軸心の一方を被
分級材料の供給口、他方を微粉の排出口とし、両者を始
端と終端とする回転自在の環状管路の中途に軸線と等距
離の全断面に亘る粗粒排出口を開口し、該開口部の後端
から管路内の始端側へ向けて分離板をそれぞれ突出し、
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 is a rotatable rotary machine having one of the rotation axes as a supply port for the material to be classified, the other as a discharge port for fine powder, and both as a start end and an end. Open the coarse particle discharge port over the entire cross section equidistant from the axis in the middle of the annular conduit, and project the separation plates from the rear end of the opening toward the start end in the conduit, respectively.
The above-mentioned problem has been solved by sequentially reducing the distance between the outer circumference and the axis of the annular conduit from the opening to the end.

またより具体的な実施レベルにおいては、以上の構成
にあって、分離板はそのまま終端側へ延長して残りの環
状管路外周を形成すること、また軸線と直角に截った環
状管路の断面が、軸心と同心の２ケの同心円に囲まれた
環状形を形成すること、あるいは軸線Ｃと同心の２ケの
同心円弧と、該円弧のそれぞれの両端を結ぶ２ケの直線
で囲まれた部分環状形を形成し、両円弧の中点P,Qを通
過する直線が軸線Ｃと交わることが最も望ましいことも
明らかにした。Further, at a more specific implementation level, in the above configuration, the separation plate is extended to the terminal side as it is to form the outer periphery of the remaining annular pipeline, and the annular pipeline cut at a right angle to the axis is formed. The cross section forms an annular shape surrounded by two concentric circles concentric with the axis, or is surrounded by two concentric arcs concentric with the axis C and two straight lines connecting both ends of the arc. It is also clarified that it is most desirable that a straight line passing through the midpoints P and Q of the two arcs intersects the axis C, forming a partially annular shape.

［作用・実施例］ 第１図（イ）は本願実施例の垂直断面図、同図（ロ）
は図（イ）のＡ−Ａ′断面を示したものである。[Operation and Embodiment] FIG. 1 (a) is a vertical sectional view of the embodiment of the present application, and FIG.
FIG. 4 shows a cross section taken along the line AA ′ of FIG.

超微粉分級機１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図
（イ）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
截った断面は図（ロ）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の中途点に軸線Ｃを中心とする全断
面に亘る開口部を設け、これが粗粒Ｇの排出口５を形成
する。The ultrafine classifier 1 is mainly composed of an annular pipeline 2 rotatably supported at one end, and one end of the pipeline is a supply port 3 of a classifying material S,
The other end is a discharge port 4 for the fine powder F, and a ring-shaped pipe is formed with these ports as a start end and an end, and the whole rotates around the axis C. As an example of the implementation of the annular pipe 2, an oval like a track in a field competition is good as shown in FIG. (A), but it may be a regular polygon, and a cross section cut perpendicular to the axis C is shown in FIG. It is desirable that the donut-like ring as shown in (b) has a wide and uniform classification effective space. However, as shown in FIG. 2, it is also possible to form a cross section obtained by cutting out only a part of the first example, and various modes can be applied to the cross section. An opening is provided at a midpoint of the annular conduit 2 over the entire cross section centered on the axis C, and this forms an outlet 5 for the coarse particles G.

少くとも、全断面に亘る排出口５の後端から分離板６
がそれぞれ流路の始端へ逆行して突出する。分離板６の
態様としては第１図（イ）に例示するように先端が鋭角
的なナイフエッヂを流路と平行に円状に突出するのが標
準的とも言えるが、分離板の向きや形状については種々
の態様を試みる余地が残っている。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。At least the separation plate 6 is connected to the rear end of the outlet 5 over the entire cross section.
Respectively project backward to the beginning of the flow path. As a mode of the separation plate 6, as shown in FIG. 1 (a), it can be said that a knife edge having a sharp tip protrudes in a circular shape in parallel with the flow path. There is still room for trying various aspects of. 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 a stepwise state each time when two sets 5A and 5B of discharge ports 5 for coarse particles G are set instead of one set as in the third embodiment shown in FIG.

分級の効率性から見れば、突出した分離板６が排出口
５の後端からそのまま延長して残りの管路の外周を形成
するのが最も望ましく、また装置の製作や取扱いなどに
おいても有利な点が多い。From the viewpoint of the efficiency of classification, it is most desirable that the protruding separation plate 6 extends from the rear end of the discharge port 5 as it is to form the outer periphery of the remaining pipeline, and is advantageous in the manufacture and handling of the apparatus. There are many points.

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とし
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 irregular coarse particles G and the fine particles F are mixed irregularly and made flowable, a dust-containing gas stream or a slurry (slurry) is continuously supplied from the supply port 3 of the ultrafine particle classifier 1 rotating at a high speed, so that the particles become particles. 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 air flow, this effect is exerted over the entire cross section of the pipeline, and when the fluid is in the form of a solid-liquid mixed slurry, it does not normally fill the entire cross section of the pipeline. 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、分離
板６が突出して分布のある範囲を境に内周側と外周側と
を分断し、分断された外周側の粗粒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。At the point where the particle size distribution is concentrically formed in the pipe, the separation plate 6 protrudes and separates the inner peripheral side and the outer peripheral side from a certain range of the distribution, and only the separated coarse particles G on the outer peripheral side are separated. Only the fine powder remaining on the inner peripheral side continues to flow down into the remaining annular pipe whose outer circumference is reduced by being forcibly extruded from the discharge port 5 opened over the entire circumference. It is finally recovered as a classified product.

この分割と以後の流通を考えると、分離板６の延長で
残りの外周を形成することが最も円滑な整流を保つ構成
と言えよう。この場合、回転速度、流体の進行速度、分
離板の大きさ、位置、角度、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。Considering this division and the subsequent distribution, it can be said that the formation of the remaining outer periphery by extending the separation plate 6 is the configuration that maintains the smoothest straightening. In this case, the properties of the material to be classified and the target classification accuracy can be sufficiently satisfied by appropriately adjusting the rotation speed, the traveling speed of the fluid, the size, the position, the angle, and the number of the separation plates.

［発明の効果］ 本願発明に係る超微粉分級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でき
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。[Effect of the Invention] The ultrafine powder classifier according to the present invention has a relatively simple structure based on the above-described operation, and is easy to manufacture, operate, and maintain. Drained,
It is possible to classify and collect only fine powders with uniform particle size with high accuracy. It is possible to freely connect multiple stages to remove coarse particles for each stage in accordance with the desired classification accuracy, and even after installation, a wide range can be obtained by fine adjustment of operating conditions, separator shape, 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図イ，ロは本願発明の実施例を示す垂直断面図
（イ）と、図（イ）におけるＡ−Ａ′断面図（ロ）、第
２図は別の実施例の軸線と直角に截った垂直断面図、第
３図は第三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）、６……分離板 Ｓ……被分級材、Ｆ……微粉、Ｇ……粗粒 Ｃ……軸線1 (a) and 1 (b) are a vertical sectional view (a) showing an embodiment of the present invention and FIG. 1 (a) is a sectional view taken along the line AA '(b), and FIG. FIG. 3 is a vertical sectional view of a third embodiment, and FIGS. 4 to 6 are vertical sectional views showing different prior arts. DESCRIPTION OF SYMBOLS 1 ... Ultra fine powder classifier, 2 ... Annular pipe line 3 ... Supply port, 4 ... Discharge port (fine powder) 5 ... Discharge port (coarse particles), 6 ... Separating plate S ... Classifying material, F: fine powder, G: coarse particles C: axis

Claims (4)

(57)【特許請求の範囲】(57) [Claims] 【請求項１】回転軸線Ｃの一方を被分級材Ｓの供給口
３、他方を微粉Ｆの排出口４とし、両者を始端と終端と
する回転自在の環状管路２の中途に全断面に亘る粗粒の
排出口５を開口し、該開口部の後端から管路内の始端側
へ向けて分離板６をそれぞれ突出し、開口部からの残り
環状管路２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 end of a rotation axis C is a supply port 3 for the material S to be classified, and the other is a discharge port 4 of fine powder F. The coarse-grain discharge port 5 is opened, and the separation plates 6 protrude from the rear end of the opening toward the starting end side of the pipe, and the remaining annular pipe 2 from the opening has a distance between the outer periphery and the axis. An ultra-fine powder classifier characterized by gradually reducing to the end. 【請求項２】請求項（１）において分離板６はそのまま
終端側へ延長して残りの環状管路外周を形成する超微粉
分級機。2. A superfine powder classifier according to claim 1, wherein the separation plate 6 is extended to the terminal side as it is to form the outer periphery of the remaining annular conduit. 【請求項３】請求項（１）又は（２）において、軸線Ｃ
と直角に截った環状管路２の断面が、軸線Ｃと同心の２
ケの同心円に囲まれた環状形を形成する超微粉分級機。3. The method according to claim 1, wherein the axis C
The cross section of the annular conduit 2 cut at right angles to the axis C is 2
Ultrafine powder classifier that forms an annular shape surrounded by concentric circles. 【請求項４】請求項（１）又は（２）において軸線Ｃと
直角に截った環状管路の断面が、軸線Ｃと同心の２ケの
同心円弧と、該円弧のそれぞれの両端を結ぶ２ケの直線
で囲まれた部分環状形を形成し、両円弧の中点P,Qを通
過する直線が軸線Ｃと交わることを特徴とする超微粉分
級機。4. A cross section of the annular conduit cut at right angles to the axis C in claim 1 or 2 connects two concentric arcs concentric with the axis C and both ends of the arc. An ultrafine classifier characterized by forming a partially annular shape surrounded by two straight lines, wherein a straight line passing through the midpoints P and Q of both arcs intersects an axis C.