KR20010026623A - Jet mill - Google Patents

Abstract

PURPOSE: A jet mill is provided to precisely divide a rotational crushing chamber to a classifying section and a crushing section, to blow thick particles to the outside and to improve the shock dependence between raw materials by forming a discharge member on the center line of the rotational crushing chamber. CONSTITUTION: A jet mill(1) contains a hollow circular rotational crushing chamber(2); crushing nozzles(3) to form swiveling flow by injecting gas of high pressure; Venturi nozzles(4) to induce crushing materials with the gas; gas mixing chambers formed on the upper parts of the Venturi nozzles; crushing material supplying portions installed in the gas mixing chambers; a pressurizing nozzle(5) arranged in the gas mixing chamber; and a discharge member(12) to discharge particles. A distance between the inducing portion of the Venturi nozzle and the discharging portion of the pressurizing nozzle is (D/d)sk. K is 8-10.

Description

Jet Mill {JET MILL}

The present invention relates to a jet mill of a horizontal flow type.

BACKGROUND ART Recently, various types of jet mills have been developed which are used in many fields such as the production of heat- weak powders or ceramic powders such as pesticides and toners, and the fine powders are collided by colliding powders by high-speed jets.

For example, JP-A-63-16981 (hereinafter referred to as `` A '') discloses the circumference of the circular separation chamber in the collision space between the collision plate and the nozzle outlet facing the main nozzle outlet for high pressure gas injection. To face a part of the circular separation chamber and the outlet side of the raw material supply passage that is passed through the main nozzle in series, and connects the bypass passage extending in the circumferential tangential direction of the circular separation chamber to the center of the circular separation chamber. Supersonic jet mill connecting the discharge path of powder "is disclosed. Moreover, as a structure of the same aspect, Unexamined-Japanese-Patent No. 57-50554, No. 57-50555, No. 57-50556, No. 4-290560, No. 5-184966, No. 7-275731 8-152742, 8-155324, 8-182937, 8-254855, 8-323234, 3-5-5110, 7-53715 No. 7-8036 and No. 6-19836 are known.

Publication No. 63-17501 (hereinafter referred to as 'B') states that a meat mixing chamber is opened by installing a raw material supply port and a grinding raw material supply nozzle for injecting high pressure gas at one end. And a pulverization pulverization chamber in which a collision plate is disposed at the other end and a pulverization nozzle for discharging high pressure gas is formed, and one end of these meat mixing chambers and the pulverization pulverization chamber is connected to an acceleration tube facing the collision plate. And a classification chamber communicating with the slewing pulverization chamber through the rectifying zone on the outer periphery of the acceleration tube, and surrounding the acceleration tube in the classification chamber to install an annular distribution plate, the inside of which is located in the discharge hole The jet mill of the structure which let the said meat mixing chamber connect to the said meat mixing chamber "is disclosed.

In Special Publication No. 64-9057 (hereinafter referred to as `` D ''), the jet mill of `` B '' was improved, and the `` projection (center pillar protruding from the collision plate toward the center of the accelerator tube) Jet mill provided with "

Japanese Patent Application Laid-Open No. 6-254427 (hereinafter referred to as 'La' publication) discloses a plurality of grinding nozzles that form a swirl flow by injecting high-pressure gas into a swing grinding chamber, and a collision provided facing the nozzles of the grinding nozzles. In a jet mill provided with a member, the collision member is a wide and flat collision plate having a lower end and an upper end shape thinly formed in the shape of a knife in a swirl flow direction, and the impact surface thereof faced in the flow direction of the swirl flow. A jet mill disposed by tilting the angle α formed with the center line in a range of 30 ° to 60 ° and fixed by an attachment means capable of adjusting the angle 'is disclosed.

Japanese Patent Application Laid-Open No. 2-111459 (hereinafter referred to as "Ma" publication) discloses a "jet mill in which an enlarged angle of the acceleration tube is formed at 7 ° to 9 °." Moreover, Unexamined-Japanese-Patent No. 7-25227 is known as a thing of the same aspect.

In addition, in the conventional jet mill, the arrangement design of the supply nozzle of the pulverized raw material and the injection nozzle for injecting the high pressure gas is performed by arranging the injection nozzle at a position equal to the circumference of the swivel crushing chamber, and equally disposing the supply nozzle of the pulverized raw material. It was arranged in one place between one injection nozzle, and the design of the total number of nozzles was odd.

However, the said conventional jet mill had the following subjects.

Jet mills described in the 'A' publication, etc., when a grinding material, for example, a new ceramic grinding material of high hardness, collides with a jet of high-pressure gas, wears at a colliding part and forms a recess. It has a problem that the fixed wall is broken and worn in a short time, and the durability is remarkably deteriorated.

The jet mill described in the 'B' publication has the same problem as the 'A' publication, and at the same time, the pulverized fine powder is fed to the center by supplying the raw material to the center part (reducing part) of the swirling airflow. It remained and had a problem that classification efficiency became low and particle size distribution became remarkably wide.

In the jet mill described in "C", the supply of the pulverized raw material and the discharge of the fine powder are simultaneously performed in the upper part of the swivel grinding chamber, so that the normal flow of the swirl flow forming the pulverizing nozzle is greatly disturbed. Disturbance of such swirling flow increases the pressure loss, and as a result, the flow rate of the swirling flow is lowered, thereby lowering the grinding capacity.

The jet mill described in the 'D' publication uses a collision effect by four impact plates installed in the swing grinding chamber, and is excellent in crushing efficiency. However, the speed of the swirl jet of the high speed jet decreases due to the presence of the impact plate. This has the problem that the shape of the powder becomes horn-shaped and difficult to control the particle size distribution.

In addition, the odd number of arrangement of the grinding raw material supply nozzle and the injection nozzle is conventional, after forming the swirling flow with an even grinding powder and turning the grinding mixture with the one grinding raw material supply nozzle. Since it is pushed into the room, segregation of the swirl flow due to the mixed phase flow which is pushed in later is easy to occur, and operation pressure is complicated because the amount of high pressure gas of the pulverized feed nozzle and the injection nozzle has to be set. As a result, the operability was lowered and segregation was liable to occur because of the odd number of nozzles, resulting in poor grinding efficiency and classification efficiency.

In addition, since each injection nozzle has one injection hole, the swing grinding chamber is manufactured by two-dimensionally analyzing the streamline of the swirl flow into one line, so that the upper portion of the swing grinding chamber (upper liner portion) And the lower portion (lower liner portion) has a problem that the flow velocity is slow, the residence time in the large-volume swirl grinding chamber becomes longer, and the wear of the liner portions of the upper portion and the lower portion is increased.

In addition, since the particle size of the fine powder is adjusted only by changing the pressure or air volume of the jet stream, segregation of the swirl flow and compression of the fine powder to the swirl grinding chamber base are easily caused by the characteristics of the pulverized raw material. It has the drawback that the wear of the ring liner, the upper liner and the lower liner of the slewing grinding chamber becomes severe, and has the problem that stable continuous production is impossible.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and enables high grinding efficiency and classification rate without segregation, thereby obtaining fine powder having a narrow particle size distribution at a very high efficiency, and at the same time, the mixed phase of the swirl grinding chamber. The flow velocity distribution of the powder can be made uniform, the dependence of the grinding material on the inner wall surface of the grinding mill can be reduced and the collision dependency between the grinding materials can be increased to prevent the wear of the wall surface. An object of the present invention is to provide a jet mill which shortens the residence time in the swinging chamber, remarkably improves the processing capacity of the grinding, and enables a long continuous processing.

The jet mill according to claim 1 of the present invention is a horizontal jet flow type jet mill, which forms a swirl flow chamber by injecting a hollow disk-shaped swing grinding chamber and a high-pressure gas inclined to the circumferential wall side to the side wall of the swing grinding chamber. M pulverizing nozzles and n venturi nozzles for introducing pulverized raw materials arranged on the sidewall of the swivel pulverization chamber together with high pressure gas (where m + n = a, a is an integer, m> n), a meat mixing chamber formed upstream of the venturi nozzle, a pulverized raw material supply unit provided in succession to the meat mixing chamber, a press-fit nozzle disposed coaxially with the venturi nozzle in the meat mixing chamber, and the slewing grinding chamber And a discharge port through which fine powder disposed in the upper part of the central part is discharged, and the distance l between the venturi nozzle introduction part of the meat mixing chamber and the discharge side of the indentation nozzle is represented by l = (D / d) × k. And k value is k = 7-12, It has a structure of k = 8-10 (however, D: diameter of a venturi nozzle introduction part and d: diameter of the discharge side of a press-fit nozzle).

Thereby, the distance l between the venturi nozzle introduction part of the meat mixing chamber and the discharge side of the indentation nozzle is represented by l = (D / d) × k, and the k value is k = 7 to 12 preferably k. = 8 to 10 (wherein D: the diameter of the venturi nozzle introduction portion and d: the diameter of the discharge side of the press-fit nozzle), the venturi nozzle and the grinding nozzle can be simultaneously raised to the same air pressure. Regardless of the kind of the grinding raw material, the grinding raw material can be sucked smoothly, and has the effect of enabling continuous operation.

Here, the distance l between the venturi nozzle and the press-in nozzle is a distance between the inlet of the inlet of the venturi nozzle and the tip of the press-in nozzle, and is preferably (D / d) × k = l, k = 7 to 12. Is expressed in the relation k = 8 to 10, and as k becomes smaller than 8, it is recognized that the blowing force of the pulverized raw material becomes small, and as k becomes larger than 10, high-speed jets from the indentation nozzle are completely It is recognized from the analysis and experimental results of the jet mill that the tendency to escape from the venturi nozzle and generate a pressure loss is recognized as not preferable.

Examples of materials for turning grinding chambers, grinding nozzles, press-fitting nozzles, and venturi nozzles include iron, aluminum, copper, titanium-based metals, alloys, or ceramics. Particularly, hard alloys have high wear resistance. desirable.

As the high pressure gas, an inert gas such as air, nitrogen, argon or the like is used in accordance with the type of grinding material or grinding conditions.

The jet mill of Claim 2 of this invention has the structure in which the said venturi nozzle provided the negative pressure generation part between the throat part and the said venturi nozzle introduction part in the invention of Claim 1. .

Thereby, in addition to the function obtained by Claim 1, by providing a negative pressure generation part between the throat part of a venturi nozzle and the venturi nozzle introduction part (upstream), the grinding raw material is ventilated by the high speed jets from a press-fitting nozzle. It sucks without leaking into a nozzle, and has the effect | action which is supplied to a swivel grinding chamber at high speed and stability.

Here, the negative pressure generating portion is formed between the throat portion and the introduction portion of the venturi nozzle. The inclination angle θ ₁ of the inlet of the throat part (the rear part of the negative pressure generating part) and the inclination angle θ ₂ of the outlet of the throat part are 0.5 ° ≦ θ ₁ ≦ θ ₂ , preferably with respect to the axis of the venturi nozzle. Is represented by 0.7 ° ≦ θ ₁ ≦ θ ₂ . Further, θ ₂ is formed from 2.5 ° to 6 °, preferably from 3 ° to 5 °.

As θ ₁ is smaller than 0.7 °, the amount of negative pressure is decreased to show a tendency of insufficiency, and as θ ₂ is larger than 5 °, a tendency of insufficiency is shown to be due to a small amount of negative pressure to be generated in the same manner. All are not desirable.

As θ ₂ becomes smaller than 3 °, pressure loss occurs at the inlet of the inlet part, and the function of the negative pressure generating part is not obtained, which tends to lower the grinding capacity, and as it is larger than 5 °, the flow velocity of the meat mixture flow stream decreases. It is recognized that the tendency to lower the grinding capacity by making it so, all of them do not cheat.

The length g of the negative pressure generating portion is 2 to 4.2 times, preferably 2.2 to 3.8 times the diameter D of the venturi nozzle introduction portion, and the length h of the throat portion is 2.25 of the diameter e of the inlet portion of the throat portion. ˜5 times, preferably 3 to 4 times.

As the length (g) of the negative pressure generating portion is smaller than 2.2 times the diameter (D) of the venturi nozzle introduction portion, there is a tendency to generate swirl flow in the inlet portion and to reduce the negative pressure of suction, and also to be larger than 3.8 times. Therefore, since the tendency to generate | occur | produce in a negative pressure generation part tends to appear, it is not all preferable.

As the length h of the throat portion becomes smaller than three times the diameter e of the inlet portion of the throat portion, the negative pressure influenced by the discharge portion tends to decrease, and as the length h becomes larger than four times, Since the tendency for compression to occur tends to occur, all of them are undesirable.

In the jet mill according to claim 3 of the present invention, in the invention according to claim 1 or 2, the total (m + n) of the grinding nozzle and the venturi nozzle is even, and 5 ≦ m ≦ 15, 1 ≦ n≤5, preferably 5≤m≤14, and 1≤n≤2.

As a result, in addition to the action obtained by claim 1 or 2, the nozzles are arranged on the circumferential wall of the turning grinding chamber at equal intervals without being ubiquitous as in the prior art, so that the pressure injected into the system from the grinding nozzle and the venturi nozzle The balance can be obtained by simultaneously adjusting the segregation, so that segregation of the swirl flow can be prevented, and as a result, an action that can facilitate operation can be obtained, and the collision dependence of the crushed raw material on the wall surface is reduced, and the collision between particles is achieved. It is possible to increase the dependence at, and to significantly suppress the wear of the liner portion in the turning grinding chamber. In addition, since the grinding raw material is prevented from segregating in the turning grinding chamber, the grinding ratio can be increased to increase the classification ratio.

Herein, as the number of grinding nozzles is smaller than 5, the tendency of the controllability of the shape and speed of the swirling flow is inferior, and as the number of grinding nozzles is larger than 14, the structure of the jet mill becomes complicated, making it difficult to control the meat mixture flow. Since the tendency to become is recognized, all are not preferable.

In the jet mill according to claim 4 of the present invention, in the invention according to any one of claims 1 to 3, each of the grinding nozzles has p stages up and down (but 2 ≦ p ≦ 5) and / or from side to side. It has the structure provided with the injection part of q column | paragraph (1 <= q <= 5).

Thereby, in addition to the action obtained by any one of claims 1 to 3, the swirl flow in the grinding zone and the classification zone in the swirl grinding chamber can be controlled three-dimensionally, and the shape of the particles is rounded, It has a function to narrow the particle size distribution and to freely control the range of the particle size distribution.

Each of the grinding nozzles has a multi-stage and / or a multi-row injection section to make the streamline in the swirl grinding chamber three-dimensional as a multi-stage layer, and to reduce the speed difference in the height direction in the mill, thereby shortening the residence time of the particles in the mill. And the effect of improving the processing capacity of the grinding.

Here, as for the stage p of the injection part of the grinding nozzle, 2 <= p <= 5, Preferably p = 3 is used. If the number of stages p is less than 2, the flow velocity of the swirl flow in the up-and-down direction in the turning grinding chamber tends to decrease as compared with the center portion, and the number of p is more than 4 or the number of rows of the injection portion q is 5 rows. It is not preferable because the tendency of the swirling flow to become unbalanced and it becomes difficult to control the swirling flow in three dimensions is exceeded.

The jet mill according to claim 5 of the present invention is the invention according to any one of claims 1 to 4, wherein each row of the injection sections and / or the diameter of the injection port at each stage and / or the injection angle of the injection sections One or more have differently formed configurations.

As a result, in addition to the action obtained by any one of claims 1 to 4, the grinding nozzle has at least one diameter of the injection port of each injection section at each stage. You can control mold and speed. By controlling the mixed swirl flow of meat in three dimensions, it is possible to form the optimum swirl flow in accordance with various grinding materials with different physical properties, thereby preventing particle size adjustment and squeezing of fine powder, and there is no segregation. It has the action to prevent wear.

In addition, since one or more of the spray angles of the rows of the grinding nozzles are different from each other, the collision dependence of the grinding materials in the swirling flow can be improved, and the optimum swirling flow is formed in accordance with various grinding materials having different physical properties. It has the action to do it.

The aperture and the spray angle of each row of the grinding nozzles and the nozzles of each stage can be changed by the nozzle diameter or the spray angle according to the grinding material by closing the upstream side with a stopper. Increasing the air volume by increasing the diameter of the injection hole, and increasing the diameter of the upper injection hole when the specific gravity such as cokes, carbon, or toner for the electrode is small, increases the collision frequency of the pulverized raw material, and thus the particle size distribution in a short time. Has a function of obtaining a narrow fine powder.

By changing the grinding nozzle, it is possible to change the spraying angle in each row, so that the turning flow in the turning mill can be controlled for each grinding material with different physical properties, and it has the function of forming the turning flow suitable for each grinding material. have.

Here, the injection angle of the injection part of each row of the grinding nozzles is adjusted in the range of 20 ° to 80 ° by exchanging the grinding nozzles, whereby the collision dependence between the grinding raw materials in the swirl flow is adjusted. Diameter of the injection hole of each column is, if the air volume of the press nozzle q _p d, and the pulverized nozzle flow rate q 1 _G d, _G is a 0.3q _p ≤q ≤2.1q _G. Here, q _p is the jet in accordance with the milnae larger than 2.1q _G decreases the generation of the negative pressure of the venturi nozzle as Less than 0.3q _G so tends to be the suction of the grinding material around occurs, and _p or q Since the tendency to disturb the swirl flow is recognized, all of them are undesirable.

As the spray angle of each thermal jet of the grinding nozzle becomes smaller than 20 °, it is recognized that the speed of grinding swirl flow is lowered, the raw materials are segregated in the grinding mill, and the grinding efficiency is lowered, or larger than 80 degrees. Therefore, since the tendency for the wear of the ring liner of a swivel grinding chamber to become large is recognized, all are unpreferable.

In addition, the spray angles of the injection sections of each row are 22.5 degrees (a grinding raw material that tends to be segregated or a grinding material that is difficult to disperse), 45 degrees (a grinding raw material that has a high hardness and tends to wear the liner part) in order to provide universality of the grinding nozzle. By combining the spraying angles of 67.5 ° (crushing raw material having compressibility), it is possible to efficiently crush from a large raw material to a small grinding material.

In the jet mill of Claim 6 of this invention, in the invention of Claim 4 or 5, the jet mill of the said grinding nozzle has the structure which has the plug insertion hole formed in the upstream.

Thereby, in addition to the action obtained by any one of claims 4 and 5, only by inserting the plug into the plug insertion hole, it has the action of obtaining an optimum grinding condition according to the grinding material.

Here, as the plug inserted into the plug insertion hole, a metal or synthetic resin can be used.

The jet mill of Claim 7 of this invention WHEREIN: The jet mill of Claim 1 thru | or 6 WHEREIN: WHEREIN: It has a center column arrange | positioned in the center of the lower surface of the said pulverization grinding chamber, the apex of the said center column, and the lower surface of the said discharge port. The above structure is located on the center line in the height direction of the slewing grinding chamber.

Thereby, in addition to the action obtained by any one of claims 1 to 6, the center of the top of the swing grinding chamber and the outlet of the bottom of the swing grinding chamber form a constitution that forms the configuration above the center line of the swing grinding chamber. It can be clearly divided into classification zone and grinding zone, and fine powder of small size and narrow particle size distribution are discharged from the outlet of the upper part of the turning grinding chamber, and coarse particles are blown out by centrifugal force generated by high speed jets. It also has the effect of improving the collision dependence between the raw materials in the high speed jets.

Here, examples of the material of the discharge or the center column include a combination of iron, aluminum, copper, titanium, metals, alloys, or ceramics. Particularly, hard alloys are preferable in terms of wear resistance.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing of the principal part of the jet mill in Embodiment 1 of this invention.

FIG. 2 is a sectional view of principal parts of the line I-I of FIG. 1; FIG.

Fig. 3 is a sectional view of the main parts of the meat mixing chamber of the jet mill in Embodiment 1 of the present invention.

It is sectional drawing of the principal part of the venturi nozzle of the jet mill in Embodiment 1 of this invention.

5 is a sectional view showing the main parts of a jet mill in accordance with the second exemplary embodiment of the present invention.

FIG. 6 is a sectional view of principal parts of the II-II line of FIG. 5; FIG.

In Fig. 7, (a) is a rear perspective view of the grinding nozzle of Embodiment 2 of the present invention, (b) is a bottom view of the grinding nozzle, and (c) is a sectional view of the main portion of III-III line of Fig. 7 (b). .

Fig. 8 is a schematic diagram showing the relationship between the bore size and the swirl flow of the first row injection port of the composite spray nozzle of the present invention.

In Fig. 9, (a) is a sectional view of the main part of the main assembly of the assembly grinding nozzle of Embodiment 2 of the present invention, (b) is a bottom view of the main assembly of the assembly grinding nozzle, and (c) is a front view of the main assembly of the assembly grinding nozzle. (D) is sectional drawing of the principal part of the fitted-injection part of the granulated grinding nozzle.

FIG. 10 is a graph showing the relationship between the particle size and cumulative particle size% of the ground fine powder of Example 2 and Comparative Example 2 of the present invention. FIG.

Fig. 11 shows the dependence of the particle size distribution% of the fine powder at a pressure of 7.5 kgf / cm 2 on the high speed jets of Example 3 of the present invention.

Fig. 12 shows the dependence of the particle size distribution% of the fine powder at 4.5 kgf / cm 2 on the pressure of the high speed jets of Example 3 of the present invention.

* Description of the symbols for the main parts of the drawings *

One… … … … … … The jet mill in Embodiment 1,

2… … … … … … Turning grinding chamber, 3... … … … … … Grinding Nozzle,

4… … … … … … Venturi nozzle, 5... … … … … … Indentation nozzle,

6... … … … … … Body casing; … … … … … Ring liner,

8… … … … … … Meat Mixing Room, 9... … … … … … Top liner,

10... … … … … … Bottom liner, 11... … … … … … Center-Column,

12... … … … … … Outlet, 13.. … … … … … Grinding Material Inlet,

14... … … … … … Fine powder outlet, 14a... … … … … … sleeve,

15... … … … … … High pressure header tube, 15a... … … … … … High pressure air pipe,

16... … … … … … Pressure regulating valve,

30... … … … … … The jet mill in the second embodiment,

31... … … … … … Composite grinding nozzle, 32,33,34... … … … … … Jet,

35... … … … … … Central pillar, 36... … … … … … outlet,

37,38,39... … … … … … Nozzle, 40... … … … … … Jet,

41... … … … … … Plug insertion hole, 42.. … … … … … plug,

50... … … … … … Assembly grinding nozzle of the modification of Embodiment 2,

51... … … … … … Body of assembly grinding nozzle, 52, 53, 54... … … … … … Insertion Hole,

52a, 53a, 54a... … … … … … Insertion Jet,

θ ₁ . … … … … … Inclination angle of the inlet of the throat part,

θ ₂ . … … … … … Inclination angle of outlet of throat part,

θ ₃ . … … … … … Angle of inclination of the inlet of the venturi nozzle,

Z ₁ . … … … … … Inlet of the venturi nozzle, Z ₂ . … … … … … Negative pressure generating unit,

Z ₃ . … … … … … Throat portion, Z ₄ ... … … … … … Discharge part of the throat part,

e… … … … … … Throat caliber,

D… … … … … … Inlet diameter of opening part upstream of venturi nozzle,

h… … … … … … Throat length, g… … … … … … Length of the negative pressure generating section,

d… … … … … … Outlet diameter of press-fit nozzle,

l… … … … … … The distance between the inlet of the venturi nozzle and the discharge side of the indentation nozzle,

α ... … … … … … The blowing angle of the venturi nozzle,

β, γ, δ. … … … … … The spray angle of the spray part of the grinding nozzle,

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described using drawing.

Embodiment 1

The jet mill in Embodiment 1 of this invention is demonstrated using drawing below.

1 is a sectional view of a main part of a jet mill in Embodiment 1 of the present invention, FIG. 2 is a sectional view of a main part of line I-I in FIG. 1, and FIG. 3 is a meat mixing chamber of a jet mill in Embodiment 1 of the present invention. 4 is a sectional view of the main part, and FIG. 4 is a sectional view of the main part of the venturi nozzle of the jet mill according to the first embodiment of the present invention.

In Fig. 1, reference numeral 1 denotes a jet mill in Embodiment 1, reference numeral 2 denotes a swirl grinding chamber formed in a hollow disk shape, and reference numeral 3 denotes a swing grinding chamber 2. 7 grinding nozzles arranged at equal intervals, reference numeral 4 denotes a venturi nozzle disposed in the turning grinding chamber 2, and reference numeral 5 denotes a meat mixing chamber upstream of the venturi nozzle 4. The indentation nozzle coaxially disposed with the venturi nozzle 4 through reference numeral 8 denotes the main body casing, the reference numeral 7 denotes the ring liner of the slewing grinding chamber 2, and the reference numeral 8 denotes the Meat mixing chamber, reference numerals 9 and 10 are upper and lower liners disposed up and down of the turning grinding chamber 2, and reference numeral 11 is an upper part which is freely detachable at the center of the lower liner 10. The central column is formed in a substantially conical shape, the reference numeral 12 is formed coaxially with the central pillar 11 and the outlet is freely disposed on the upper liner 9, the reference numeral 13 is a meat horn The pulverized raw material inlet continuously connected to the yarn 8, the reference numeral 14 is a fine powder outlet formed by a sleeve 14a, the reference numeral 14a is a sleeve, the reference numeral 15 is a high-pressure header tube, and a reference numeral 15a. ) Denotes a high pressure gas pipe for sending high pressure gas from the high pressure header pipe 15 to the grinding nozzle 3 or the press injection nozzle 5, and the reference numeral 16 for adjusting the pressure of the high pressure gas pipe 15a. Pressure regulating valve.

In Fig. 2, α is an injection angle of the venturi nozzle, and γ is an injection angle of the injection portion of the grinding nozzle. α is adjusted to 20 ° to 70 °, preferably 30 ° to 50 °. As it is smaller than 30 °, it tends to cause resistance to the intake of the mixed phase and disturbs the swirl flow, and as it is larger than 50 °, there is a tendency that squeezing or abrasion at the liner part tends to occur easily. not. γ depends on the number of grinding nozzles and the type of grinding material.

In Fig. 3, D is the inlet diameter of the opening on the upstream side of the venturi nozzle 4, d is the outlet diameter of the indentation nozzle 5, and l is the inlet of the venturi nozzle 4 and the indentation nozzle 5. Distance from the discharge side.

The distance l between the introduction portion of the venturi nozzle 4 of the meat mixing chamber 8 and the discharge side end portion of the indentation nozzle 5 satisfies the expression of l = (D / d) × k. ) Is determined. Here, k value is a value obtained by analysis and experiment, and k = 7-12, Preferably the value of 8-10 is employ | adopted.

In Fig. 4, θ ₁ is the inclination angle of the inlet (rear of the negative pressure generating portion Z ₂ ) of the throat portion Z ₃ with respect to the axis of the venturi nozzle, and θ ₂ is the throat portion of the venturi nozzle ( Inclination angle of the exit of Z ₃ ), θ ₃ is the inclination angle of the inlet portion Z ₁ of the venturi nozzle, Z ₁ is the inlet portion of the widened meat mixture upstream of the venturi nozzle upstream, Z ₂ is the axis at the inlet end gentle slope so the negative pressure producing formed portions, Z ₃ is the throat section, Z ₄ substantially formed parallel to the axis is widened discharge portion in the rear of the throat section (Z _3), (e) is a throat section (Z ₃ Is the length of the throat portion Z ₃ , and g is the length of the negative pressure generating portion Z ₂ .

The inclination angle θ ₁ of the inlet of the throat portion Z ₃ (after the negative pressure generating portion) and the inclination angle θ ₂ of the outlet of the throat portion Z ₃ are 0.5 ° relative to the axis of the venturi nozzle. the θ ₁ ≤θ _2, preferably is formed of a 0.7 ° ≤θ ₁ ≤θ _2. And (theta) ₂ is 2.5 degrees-6 degrees, Preferably it is formed in 3 degrees-5 degrees. Further, the length g of the negative pressure generating portion Z ₂ is 2 to 4.2 times the diameter D of the venturi nozzle introduction portion, preferably 2.2 to 3.8 times the length h of the throat portion Z ₃ . Is formed 2.25 to 5 times, preferably 3 to 4 times the diameter e of the inlet of the throat portion Z ₃ .

The operation | movement is demonstrated below about the jet mill of Embodiment 1 comprised as mentioned above.

The high pressure gas is supplied to the grinding nozzle 3 and the press-in nozzle 5 at the same pressure only by opening one pressure regulating valve 16. The grinding raw material is supplied from the grinding raw material introduction port 13, and the grinding raw material and the air are mixed in the meat mixing chamber 8 by the high speed jets injected from the indentation nozzle 5. When the distance l between the venturi nozzle 4 and the press-in nozzle 5 satisfies the relationship of (D / d) × k = l, k = 7-12, preferably 8-10, the pulverization is performed. Since there is no pressure loss at the outlet of the chamber 2 and the venturi nozzle 4, the mixed phase flow from the venturi nozzle 4 is introduced from the venturi nozzle 4 into the swirl grinding chamber 2 at a stable and high speed. . High-speed jets from the grinding nozzle 3 generate swirl flow in the turning grinding chamber 2, and a grinding zone is formed on the outer circumferential side of the turning grinding chamber 2, and classified at the center side of the turning grinding chamber 2 Zones are formed. Due to the high speed jet and the swirl flow, the grinding raw materials collide with each other, and the grinding raw materials are pulverized. The fine powder classified in the classification zone is discharged through the fine powder discharge port 14 from the outlet 12 of the turning grinding chamber, and at the same time, the coarse particles are turned around by the centrifugal force generated by the turning, and the coarse particles collide with each other. It is crushed repeatedly.

By the negative pressure generating portion of the venturi nozzle, the meat mixing upstream introduced from the inlet portion is accelerated and injected into the swing grinding chamber. In addition, while maintaining the inlet portion of the press-fit nozzle and the venturi nozzle at a predetermined distance, the negative pressure generating portion is provided to balance the swirl flow by spraying the mixed phase flow into the swirl grinding chamber without losing the air volume and the wind pressure of the press-press nozzle. Controlled swirling flow can be achieved without breaking down.

As described above, according to the first embodiment, it is possible to realize a smooth meat mixture flow of the venturi nozzle, and as a result, it is possible to achieve high grinding efficiency and classification rate without generating segregation, and to effectively make fine powder having a narrow particle size distribution. In addition, it is possible to provide a jet mill with a uniform flow velocity distribution in the mixed phase of the slewing grinding chamber, shortening the residence time in the slewing grinding chamber of the grinding material, and remarkably improving the processing capacity of the grinding mill. have.

Embodiment 2

The jet mill in Embodiment 2 of this invention is demonstrated using drawing below.

Fig. 5 is a sectional view of an essential part of a jet mill in Embodiment 2 of the present invention, Fig. 6 is a sectional view of an essential part of line II-II in Fig. 5, and Fig. 7 (a) is a rear perspective view of the grinding nozzle in Embodiment 2 of the present invention. 7 (b) is a bottom view of the grinding nozzle, and FIG. 7 (c) is a cross-sectional view of the main parts of the III-III line of FIG. 7 (b). In addition, the same thing as Embodiment 1 attaches | subjects the same code | symbol, and abbreviate | omits description.

In Fig. 5, reference numeral 30 denotes a jet mill according to the second embodiment, and reference numeral 31 denotes a composite injection nozzle in which nine injection parts are formed in three stages of up and down, and three rows in a row. Seven (31) are arrange | positioned at the turning grinding chamber 2 at equal intervals. Reference numerals 32, 33 and 34 denote injection parts respectively formed at the upper and lower ends of the composite injection nozzle 31, and reference numerals 35 and 36 denote the center column and the discharge port.

In Fig. 6, reference numeral 37 denotes an injection hole of the first thermal grinding nozzle in which the injection angle β is 67.5 °, and reference numeral 38 denotes a second thermal grinding nozzle in which the injection angle γ is 45 °. The injection hole in Fig. 39 is the injection hole of the third thermal grinding nozzle in which the injection angle δ is 22.5 degrees, and the reference numeral α is the injection angle of the venturi nozzle.

In Fig. 7, reference numeral 40 denotes an injection part of the composite injection nozzle 31, and reference numeral 41 denotes a kind of pulverized raw material formed by being widened at the base of the injection part 40 of the composite injection nozzle 31. (B) A plug insertion hole for inserting and attaching the plug 42 according to processing conditions, and 42 is a plug.

The operation | movement is demonstrated below about the jet mill in Embodiment 2 comprised as mentioned above.

In the ring liner 7 of the turning grinding chamber 2, seven composite grinding nozzles 31 are provided at predetermined positions and angles, and one composite grinding nozzle 31 has nine injection holes in total in three rows and three stages. It is. The upper injection section 32 controls the upper layer in the height direction of the jet mill 30, the middle injection section 33 controls the intermediate layer in the height direction of the jet mill 30, the lower injection section ( 34) can control the shape and speed of the grinding swirl flow in three dimensions by controlling the lower layer in the height direction of the jet mill. By controlling the injection angle β of the first row injection port 37 of the composite grinding nozzle 31 in the range of 50 ° to 80 °, it is possible to control the dependency of the collision between the grinding raw material and the ring liner 7 of the turning grinding chamber. Can be. By controlling the injection angle γ of the second row injection port 38 of the composite grinding nozzle 31 in the range of 30 ° to 60 °, the collision dependence between the grinding raw materials in the swirl flow can be controlled. By adjusting the injection angle δ of the third row injection port 39 of the composite grinding nozzle 31 in the range of 20 ° to 50 °, the commutation time of the pulverized raw material in the jet mill can be controlled. Due to the high speed jets from each injection port of the composite grinding nozzle 31, swirl flow is generated in the swing grinding chamber 2, a grinding zone is formed on the inner circumferential side of the swing grinding chamber 2, and the swing grinding chamber 2 A classification zone is formed at the center of The raw materials collide with each other by the high speed jet and the swirl flow, and the grinding raw materials are pulverized. The fine powder classified in the classification zone is discharged through the fine powder discharge port 14a from the discharge opening 36 of the turning grinding chamber, and the coarse particles are rotated outward by the centrifugal force generated by the turning, so that the grinding raw materials It collides and it crushes repeatedly.

In addition, by inserting and inserting the plug 42 into the insertion hole 40, the swirl angle suitable for various powders can be formed by controlling the injection angle and the number of injection holes of the injection section.

Next, the state of the swirl flow at the time of changing the diameter of the injection port of each injection part by making the injection part of a grinding nozzle into one row is demonstrated using a schematic diagram.

Fig. 8 is a schematic diagram showing the relationship between the bore size and the swirl flow of the first row injection port of the composite spray nozzle.

In Fig. 8, by changing the diameter of the one row injection port of the grinding nozzle 31 at each stage, the swirl flow according to the grinding raw material can be obtained.

In the case of (a), since the swirl flow can be uniformly formed in the entire layer, various kinds of ground raw materials can be ground with high efficiency.

In the case of (b), since a large amount of air volume is obtained in the upper layer, it is suitable for a pulverized raw material having light specific gravity such as toner or carbon.

In the case of (c), since a large amount of air volume is obtained in the lower layer, it is suitable for a pulverized raw material having a high specific gravity such as fine ceramics.

In the case of (d), it is suitable for mixed pulverized raw materials of powders having different specific gravity.

In the case of (e), it is suitable for pulverizing various powders with a small power.

In the case of (f), it is suitable for the pulverized raw material of powder having a high specific gravity and particularly poor dispersibility.

In the case of (g), it is suitable for pulverized raw materials of powder with light specific gravity and brittleness.

Here, it was found by the confirming test that the ratio of the public-to-small-scale as a ratio was a: b: c = a: 1.5 to 3a: 3a to 6a when a small diameter was a, a medium diameter was b, and a large diameter was c. .

Next, the modification of Embodiment 2 is demonstrated using drawing.

Fig. 9 (a) is a sectional view showing main parts of the assembly grinding nozzle main body of Embodiment 2 of the present invention, Fig. 9 (b) is a bottom view of the assembly grinding nozzle main body, and Fig. 9 (c) is a front view of the assembly grinding nozzle main body. 9 (d) is a cross-sectional view of the main parts of the fitted jetting portion of the assembly grinding nozzle.

In Fig. 9, reference numeral 50 denotes an assembling pulverization nozzle having an insertion hole of a fitted jetting part provided in which each row penetrates at a different angle in the axial direction of the main body in the modification of Embodiment 2 of the present invention. Reference numeral 51 is a main body of the assembly grinding nozzle, and 52, 53, 54 are insertion holes formed in the shape of horns into which the injection nozzles of the first row, the second row, and the third row are inserted, respectively. The insertion holes 52 and 54 are arranged in the axial direction of the main body 51 so that a predetermined injection angle (for example, 22.5 degrees and 67.5 degrees) is obtained when the assembly grinding nozzle 50 is inserted into the turning grinding chamber. It is slanted and drilled. Reference numerals 52a, 53a, and 54a denote insertion jets fitted into the insertion holes 52, 53, and 54, respectively, and reference numerals 42 denote insertion holes 52, 53, ( It is a plug inserted as needed in the plug insertion hole formed in the upstream of 54).

The operation of the granulated grinding nozzle in the modification of the second embodiment configured as described above will be described below.

The diameters and / or spray angles of the injection holes of the rows 52, 53, 54 and / or the ends 32, 33, 34 of the granulated grinding nozzle 50 are the type of grinding material or the grinding conditions. By selecting and inserting the appropriate optimum fitting injection | pouring part 52a, 53a, 54a according to this, the optimum swirl flow according to a grinding raw material is obtained by this.

Since the insertion hole is formed in a horn shape, even when the high-pressure gas is introduced, the jetting portion can maintain the predetermined position and angle without shifting.

Then, the insertion holes 52 and 54 are drilled at an angle with respect to the axial direction of the main body 51 so as to obtain a predetermined spray angle, or the insertion holes 52 and 54 are parallel to the axial direction of the main body 51. The injection holes of the injection-type injection parts 52a and 54a may be inclined at a predetermined angle with respect to the axial direction of the main body 51.

As described above, according to Embodiment 2, in addition to the action obtained in Embodiment 1, the injection angle α of the venturi nozzle and the injection angle β of the injection portion of the composite grinding nozzle are adjusted, By providing one or more rows and one or more stages of injection nozzles in the composite grinding nozzle, it becomes possible to control the swirl flow of the grinding zone and the classification zone in the rotary grinding chamber three-dimensionally, and to prevent particle size adjustment and crushing of fine powder. It prevents segregation of crushed raw materials in the slewing grinding chamber, minimizes abrasion of the ring part, the upper part and the lower part of the liner part, and improves the crushing efficiency, makes the shape of the particles round and narrows the particle size distribution. At the same time, it is possible to provide a horizontal flow type jet mill capable of freely controlling the particle size distribution range.

In the above description, an example in which seven grinding nozzles are provided at predetermined angles except for the venturi nozzle at the position where the circumference grinding chamber 2 is divided into eight equal parts is described. It can be implemented in the same aspect.

Although the number of rows has been described in three rows, the number of rows may be one row or a plurality of rows.

(Example)

Next, this invention is demonstrated concretely based on an Example.

Example 1

By means of a jet mill according to the first embodiment it was subjected to the grinding tests of V ₂ O ₅ catalyst.

As the turning grinding chamber, an inner diameter of 400 mm and a height of 70 mm were used.

The grinding nozzles were arranged at respective positions in which the circumferential wall of the turning grinding chamber was divided into eight parts using seven injection nozzles having a diameter of 3.4 mm and one venturi nozzle.

(2) grinding materials:

V ₂ O ₅ catalyst, X ₅₀ = 15 μm.

(3) Grinding condition:

The air pressure of the press-fitting nozzle and the grinding nozzle was 7 kgf / cm 2, the grinding material introduction amount was 60 kg / hr, and the continuous operation was 72 hours.

In the above condition it was subjected to the grinding tests of V ₂ O ₅ catalyst. After the end of operation, the jet mill was analyzed to measure the V ₂ O ₅ catalyst press layer of the ring liner in the slewing chamber. As a result, the thickness of the maximum crimping layer was 3.7 mm.

(Comparative Example 1)

In Comparative Example 1, a grinding test of the V ₂ O ₅ catalyst was conducted using a conventional jet mill.

(1) size and structure of jet mill:

As the swirl grinding chamber, one having the same size as in Example 1 was used. In addition, the grinding nozzle and the venturi nozzle used the same thing as Example 1. Eight grinding nozzles were arrange | positioned in the eight equal positions of the turning grinding chamber, and one venturi nozzle was arrange | positioned between two grinding nozzles.

(2) grinding materials:

The same thing as Example 1 was used.

(3) Grinding condition:

It carried out under the same conditions as in Example 1.

After the end of operation, the jet mill was analyzed to measure the V ₂ O ₅ catalyst pressed layer of the ring liner in the slewing chamber. As a result, the thickness of the maximum crimping layer was 12 mm.

As can be clearly seen from the thickness values of the maximum compressed layer of Example 1 and Comparative Example 1, the jet mill of Example 1 was operated for 72 hours, compared to the conventional one, and then the V ₂ O ₅ catalyst maximum of the ring liner in the jet mill. It was found that the thickness of the compressed layer was only 31% of Comparative Example 1.

As mentioned above, according to Example 1 of Embodiment 1, it turns out that the grinding | pulverization raw materials can collide with the high speed jet in a slewing grinding chamber, and grinding | pulverization efficiency can be improved. In addition, the shape of particle | grains is all round. This shows that a fine powder of high quality is obtained.

Example 2

Using the jet mill in Embodiment 2, the grinding test of the V ₂ O ₅ catalyst was carried out.

(1) size and structure of jet mill:

As the swirl grinding chamber, the same one as in Example 1 was used.

Seven composite grinding nozzles were used having three nozzles (diameter of 2.0 mm) in one row. One Venturi nozzle was used, and it arrange | positioned in each position which divided the circumferential wall of the turning grinding chamber into 8 equal parts.

(2) Grinding raw materials and (3) Grinding conditions were performed under the same grinding raw materials and conditions as in Example 1.

In the evaluation, the pulverized fine powder was measured for particle distribution and particle size with a laser particle distribution system. The results are shown in FIG. Fig. 10 is a graph showing the relationship between the particle diameter and the cumulative particle diameter% of the fine powder.

(Comparative Example 2)

Comparative Example 2 was carried out under the same conditions as in Example 2 using the jet mill of Comparative Example 1. Next, evaluation was performed under the same conditions as in Example 2. The results are shown in FIG.

As apparent from Fig. 10, it was found that the maximum particle diameter of the pulverized fine powder of Example 2 was 6.0 mu m, while in Comparative Example 2 it was 32.0 mu m. It can be seen that the particle size distribution range can be narrowed to 18% of Comparative Example 2. Example 2 improves the grinding efficiency by colliding the grinding materials with the high speed jet in the turning grinding chamber, and improves the grinding efficiency without segregating the grinding raw materials in the turning grinding chamber, and the particle size as fine powder precision. The distribution can be narrowed and the particle size distribution range can be adjusted.

Further, with respect to the Example 2 particle size (X ₅₀₎ of the 1.82㎛, it can be seen that in Comparative Example 2 particle size (X ₅₀₎ of the 3.82㎛. Example 2 is exemplary of the particle size (X ₅₀₎ from which the comparative example 2 which is only a 47% of the particle size (X ₅₀₎ of Example 2, the particle size distribution can be seen that remarkably narrow.

In addition, when the jet mill of Example 2 was analyzed and the inside of the turning grinding chamber was confirmed after the end of the experiment, the crushing phenomenon of the fine powder could not be confirmed. On the other hand, in the comparative example 2, the crimp of the same aspect as the comparative example 1 was shown. This shows that segregation does not occur in Example 2, and the swirl flow is balanced.

Example 3

Using the jet mill in Embodiment 2, the dependence of the particle size distribution of the grinding | pulverization raw material on the pressure of high speed jets was confirmed.

(1) High speed jets were carried out at a pressure of 7.5 kgf / cm 2 (a) and 4.5 kgf / cm 2 (b).

(2) Grinding material and introduction amount:

Using an epoxy-based resin (X ₅₀ = 50㎛), each of the introduced amount was set to 10kg / hr.

The pulverized fine powder was measured in the same manner as in Example 2 distribution range and particle size distribution. The results are shown in FIGS. 11 and 12. Fig. 11 shows the dependence of the particle size distribution of the fine powder at the pressure of the high speed jets at 7.5 kgf / cm 2, and Fig. 12 is the particle size distribution of the fine powder at the pressure of 4.5 kgf / cm 2 at the high speed jets. This diagram shows the dependency of.

As apparent from Figs. 11 and 12, it can be seen that Fig. 12 is in the range of 7.0 µm to 35.0 µm, while the particle size distribution of the fine powder in Fig. 11 is in the range of 2.5 µm to 23.3 µm. It can also be seen that the particle size distribution curve hardly changes.

It can be seen from this that only by changing the pressure of the high speed jets, it is possible to freely change the size of the particle size in a narrow particle size distribution.

As described above, according to the jet mill in the present invention, the following excellent effects can be realized.

According to the jet mill of Claim 1 of this invention,

(1) The distance l between the venturi nozzle introduction portion of the meat mixing chamber and the discharge side of the indentation nozzle is represented by l = (D / d) × k, and the k value is k = 7-12, preferably k = Since it is formed to satisfy 8 to 10 (wherein D is the diameter of the venturi nozzle introduction part and d is the diameter of the discharge side of the press-fit nozzle), the venturi nozzle and the grinding nozzle are simultaneously raised to the same air pressure and the grinding material Regardless of the type, the grinding raw material can be sucked smoothly and continuous operation can be made possible.

According to the jet mill of Claim 2 of this invention, in addition to the effect of Claim 1,

(2) By providing a negative pressure generating portion between the throat portion of the venturi nozzle and the venturi nozzle introduction portion (upstream side), the pulverized raw material is sucked without leaking into the venturi nozzle by the high speed jets from the indentation nozzle, It can be supplied stably to the turning grinding chamber.

According to the jet mill of Claim 3 of this invention, in addition to the effect of any one of Claims 1 or 2,

(3) Since the nozzles are arranged on the circumferential wall of the turning grinding chamber at equal intervals without being unevenly distributed as in the prior art, a balance can be obtained by matching the pressure injected into the system from the grinding nozzle and the venturi nozzle. As a result, it is possible to reduce the occurrence of collisions on the surface of the pulverized raw material and to increase the dependence in the collision between particles, and to significantly suppress the wear of the liner part in the slewing grinding chamber. Can be. In addition, by preventing the raw materials from being segregated into the slewing grinding chamber, the grinding efficiency can be improved and the classification rate can be increased.

According to the jet mill of Claim 4 of this invention, in addition to the effect of any one of Claims 1-3,

(4) It is possible to control the vortex flows in the grinding zone and the classification zone in the slewing grinding chamber three-dimensionally, rounding the shape of the particles, narrowing the particle size distribution, and freely controlling the range of the particle size distribution. have.

(5) By holding a multi-stage jetting unit in the multi-row grinding nozzle, the streamline in the swivel grinding chamber is three-dimensional as a multi-stage layer, and by reducing the speed difference in the height direction in the mill, the residence time of the particles is shortened, and the grinding processing Improve your skills.

According to the jet mill of Claim 5 of this invention, in addition to the effect of any one of Claims 1-4,

(6) Since the grinding nozzles have different injection angles in each injection section in multiple rows, the shape and speed of the three-dimensional grinding swirl flow of the horizontal plane and the height can be controlled. By controlling the mixed swirl flow of meat in three dimensions, it is possible to form the optimum swirl flow in accordance with various grinding materials with different physical properties, thereby preventing particle size adjustment and crushing of fine powder, and eliminating segregation. Wear of the liner portion can be prevented.

(7) Since at least one of the diameter and / or injection angle of the injection port of each row of the grinding nozzles is different, it is possible to improve the collision dependence between the grinding raw materials in the swirling flow and to provide various grinding materials with different physical properties. It is possible to form an optimum swirl flow in accordance with.

(8) Since the diameters of the thermal nozzles of the grinding nozzle can be changed, in the case of heavy specific gravity such as ceramics, the diameter of the lower injection ports can be increased to increase the air volume, and also the specific gravity of coke, carbon, toner, etc. for electrodes. In this small case, by increasing the diameter of the upper injection port, the collision frequency of the pulverized raw material can be increased to obtain a fine powder having a narrow particle size distribution in a short time.

(9) By changing the grinding nozzle, the spray angle can be changed in each row, so that the swirl flow in the jet mill can be controlled for each grinding material having different physical properties, and a swirl flow suitable for each grinding material can be formed. .

According to the jet mill of Claim 6 of this invention, in addition to the effect of any one of Claims 4 or 5,

(10) Only by inserting the plug into the plug insertion hole, optimum grinding conditions according to the grinding material can be obtained.

According to the jet mill of Claim 7 of this invention, in addition to the effect of any one of Claims 1-6,

(11) The center column of the upper surface of the turning grinding chamber and the outlet of the lower surface of the turning grinding chamber form a configuration above the center line of the turning grinding chamber, so that the turning grinding chamber can be clearly divided into the classification zone and the grinding zone, The fine powder and the narrow particle size distribution are discharged from the outlet of the upper part of the pulverization chamber, and the coarse particles are blown out by the centrifugal force generated by the high speed jets, thereby improving the dependency of the grinding materials in the high speed jets. Can be.

Claims (7)

A horizontal-flow jet jet mill, a hollow disk-shaped swing grinding chamber, m grinding nozzles for forming a swirl flow by injecting high pressure gas inclined toward the circumferential wall by a jetting port on the side wall of the swing grinding chamber, and the swirl grinding chamber. N venturi nozzles (where m + n = a, a is an integer, m> n) for introducing the grinding raw material disposed on the side wall with high pressure gas, a meat mixing chamber formed upstream of the venturi nozzle, And a pulverized raw material supply unit provided in succession to the meat mixing chamber, a press-fit nozzle disposed coaxially with the venturi nozzle in the meat mixing chamber, and a discharge port through which fine powder disposed at an upper portion of the center of the pulverizing chamber is discharged. The distance l between the venturi nozzle introduction portion of the meat mixing chamber and the discharge side of the indentation nozzle is represented by l = (D / d) × k, and the k value is k = 7 to 12, preferably k = 8. 10, where D is the diameter of the venturi nozzle inlet and d is the indentation furnace The diameter of the discharge side) of the jet mill, characterized in that. The jet mill according to claim 1, wherein the venturi nozzle includes a negative pressure generating portion between the throat portion and the venturi nozzle introduction portion. The total (m + n) of the grinding nozzle and the venturi nozzle is an even number, and 5 ≦ m ≦ 15, 1 ≦ n ≦ 5, preferably 5 ≦ m ≦ 14, 1 Jet mill, characterized in that ≤ n ≤ 2. The grinding nozzle according to any one of claims 1 to 3, wherein each of the grinding nozzles has p columns (up to 2 ≦ p ≦ 5) and / or q columns (up to 1 ≦ q ≦ 5) up and down. The jet mill is provided with the injection part of the. The jet according to any one of claims 1 to 4, wherein at least one of the rows of the jetting section and / or the diameter of the jetting port at each stage and / or the jetting angle of the jetting section is formed differently. wheat. The jet mill according to claim 4 or 5, wherein the jetting portion of the grinding nozzle has a plug insertion hole formed upstream. The center of a lower surface of the said turning grinding chamber is provided, and the apex of the said center pillar and the lower end surface of the said discharge port are the height direction of the said turning grinding chamber. A jet mill characterized by being on a center plane.