JPS5924349Y2 - Powder mixture manufacturing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for producing a powder mixture having a desired viscosity composition ratio.

When an intermediate product or a product is produced by mixing powders and granules having different viscosity compositions at a desired ratio, the viscosity composition ratio becomes an extremely important factor in determining the properties of the product.

For example, the viscosity composition of the starch raw material (wheat flour) used in soy sauce brewing has a decisive influence on the quality of koji production and, ultimately, the quality of the soy sauce.Therefore, knowledge regarding the optimal viscosity composition has even been published.

In addition, the particle size structure of raw materials in sintered products such as ceramics has a large effect on shrinkage during firing of the product and on the strength of the product.

In addition, the particle size composition of foundry sand used in casting has a large effect on strength, gas release, casting surface (scooping), etc.

Furthermore, it is known that the adhesion of granular agricultural chemicals to plants differs depending on their viscosity structure, and the viscosity structure is an important factor in the effective use of agricultural chemicals.

Furthermore, the particle size structure of the graphite in a pencil is reflected in the sharpness of the lines drawn.

In this way, control of the viscosity composition of a powder or granule is a very important characteristic value when handling a powder or granule mixture.

Therefore, this viscosity structure is also important know-how in the production of intermediate products or products using powder mixtures as raw materials.

Conventionally, as a method for obtaining a powder mixture having a desired particle size composition ratio, the powder and granule are pre-fractionated and stored for each known particle size composition by controlling the clearance etc. in the crusher in the crushing process. A typical method is a batch method in which required amounts of each component are taken out and mixed, but the particle size composition ratio in this method depends solely on the granulation and pulverization technology.

Therefore, in order to obtain an accurate particle size composition ratio, highly accurate granulation and
Grinding technology is required.

In addition, a fundamental problem is that according to the above method, the amount of each particle size component to be fractionated is determined independently by adjustments in the granulation and pulverization processes, resulting in an imbalance between each component, resulting in mixing. In some cases, excess or deficiency may occur, resulting in the system being unable to operate.

For this reason, although we recognize the importance of the particle size structure in a mixture, in reality, the reality is that the mixture is granulated and pulverized under certain conditions and then mixed as is.

Therefore, it was difficult to obtain a mixture with an accurate particle size composition ratio.

The present invention proposes a technology that eliminates the various drawbacks associated with the above-mentioned batch method, and that can accurately control the particle size composition ratio to continuously obtain a powder mixture having a desired particle size composition ratio. According to the present invention, an apparatus is proposed for continuously producing a powder mixture having a desired particle size composition from particles having a constant particle size or powder having a certain particle size distribution.

As mentioned above, the present invention can be applied to the mixing of all kinds of granular materials and similar effects can be expected, but some examples will be explained below.

As a first example, 20% powder, 30% grains, 50% coarse grains.
An example of producing a mixture of wheat flour having a particle size composition ratio will be described with reference to FIG.

Figure 1 shows the system diagram.

Wheat flour as a raw material is added with steam in the granulation process, granulated in a pellet mill, dried in a fluidized fluid dryer, and then supplied to the next pulverization process.

In the grinding step, the granulated flour is ground by any conventional type of grinder, such as a roll grinder, to adjust the particle size structure within a coarse range.

Rough adjustment of the particle size structure in the crushing process is performed by adjusting the roll clearance or selecting the tooth profile of the brake roll in the case of a roll type crusher.

The pulverized flour powder is supplied to the next particle size sorting step, where it is passed through three types of sieve screens S1. S2. A multi-stage sieve machine consisting of S3 separates particles into 4 separate streams A for each particle size within a specific range.
, B, C.

It is classified as D.

The sieve screen S1 has 8 meshes, the sieve screen S2 has ]-4 meshes, and the sieve screen S3 has 50 meshes.

What is important here is that in order to obtain the desired particle size composition ratio in this example, the components that do not pass through the sieve screen S1 must be There is almost nothing and it passes through the sieve screen 8, but the sieve screen S2
Components that do not pass through are 50% or more of the entire powder and granular material, sieve screen S2
It is necessary that the components that pass through the sieve screen S3 but not the sieve screen S3 account for 30% or more of the entire powder and granular material, and the components that pass through the sieve screen S3 must be not zero.

Among the classified four-command branch streams, component stream A is powder, and is continuously fed to the mixing process by the electromagnetic feeder MFA.

The flow rate of component flow A is measured by impact line flowmeter FA.

Similarly, component stream B is fine particles and is continuously fed to the mixing process by electromagnetic feeder MFB, and component stream C is coarse particles and is continuously fed to the mixing process by electromagnetic feeder MFC. .

The flow rates of component streams B and C are measured by impact line flowmeters FB and FC, respectively.

The excess of the component stream A is returned to the granulation process by the screw feeder SFA for granulation, then pulverized in the pulverization process and fed again to the particle size selection process.

The excess of component streams B and C is fed to screw feeder SFB.
Then, it is supplied to a second pulverization step different from the above by SFC, and after being pulverized, it is again supplied to the particle size selection step.

The component stream is fed in its entirety directly to a second grinding step where it is ground and also fed to a particle sizing step.

In the second pulverization step, the flour powder is further pulverized using an impact mill, ball mill, impact pulverizer, or the like.

Proportional setters PB and PC are provided for component flows B and C, respectively, and proportional setter PB is connected to flowmeter F.
Output signal corresponding to the flow rate of component flow A from A and component flow B
The electromagnetic feeder MF receives an output signal corresponding to the flow rate of
Control the feeding amount of B.

In this example, since the desired particle size composition ratio is 20% powder, 30% grains, and 50% coarse particles, the electromagnetic feeder MF
The feeding amount of B is determined by the electromagnetic feeder M by this proportional setting device PB.
It is controlled to be 1.5 times the feed amount of FA.

Similarly, the proportional setter PC controls the component flow A from the flowmeter FA.
The feeding amount of the electromagnetic feeder MFC is controlled in response to an output signal corresponding to the flow rate of the component flow C and an output signal corresponding to the flow rate of the component flow C.

Specifically, the feed amount of the electromagnetic feeder MFC is controlled by the proportional setting device PC to be 2.5 times the feed amount of the electromagnetic feeder MFA.

The proportional setting device may be of the type that receives a signal corresponding to the flow rate in the form of DC voltage and outputs an output signal corresponding to the desired feed rate in the form of DC current. The flow rate can be set within a range of ±0.2 with respect to the ratio setting value, and an alarm can be issued if the flow rate deviates from this set value.

In this way, component streams A, B, and C are 20%, 30%, and 50%.
% ratio is continuously fed to the mixing step and mixed to obtain a flour granule mixture with a desired particle size composition ratio.

Furthermore, in the above embodiments, when the raw material is wheat flour, it is subjected to a granulation process in advance, but the granulation process may be omitted depending on the particle size of the powder raw material.

In the above embodiment, the screw feeder 5FA-8
FC1 electromagnetic feeder MFA-MFC1 flowmeter FA-FC
may have a conventional structure.

Next, with reference to FIG. 2, an example relating to the production of finely divided agricultural chemicals will be described.

In FIG. 2, the same letters as those in FIG. 1 indicate the same components, and the configuration and operation of each component are the same as those described with respect to FIG. 1, so a description thereof will be omitted.

92 parts of clay, 5 parts of sodium ligninsulfonate, 0.5 part of phosphoric acid, 2 parts of surfactant, and 0.5 part of kasugamycin (purity 60%) are blended with pneumascale, and mixed with a ribbon mixer to obtain raw materials. It is supplied to the granulation process as

In the granulation step, 100 parts of this mixture are mixed with stirring while spraying 5 parts of water, granulated with a pellet mill, and then dried with a fluidized fluid dryer.

The granular material thus obtained is supplied to the next pulverization step and pulverized by a pulverizer with adjusted roll clearance and the like.

Next, the pulverized powder is supplied to a particle size sorting process, where three types of sieve screens S1. It is classified by a multistage sieve machine composed of S2 and S3.

The entire amount of the component stream A passing through the sieve screen S3 is returned to the granulation step by a suitable feeding device, granulated there, then ground in a pulverization step and fed again to the particle size selection step.

The component flow B that has passed through the sieve screen S2 and is on the sieve screen S3 is continuously fed to the mixing process by an electromagnetic feeder MFB via an impact line flow meter FB.

Similarly, the component stream C that has passed through the sieve screen S1 and is on the sieve screen S2 passes through the proportional setting device PC, which is controlled to have a constant ratio of 0.25 times the flow rate of the component stream B, and then continues to the mixing process by a predetermined amount. will be sent to

The excess of component streams B and C is fed to screw feeder SFB.
and is fed to a second grinding step by SFC where it is ground and returned to the particle size selection step.

The same holds true for the total amount of component streams that do not pass through the sieve screen S1.

In this way, it was possible to continuously prepare a fine granular pesticide having a particle size composition ratio of 79% of the component in the particle size range of 145 mesh to 70 mesh and 21% of the component in the particle size range of 70 mesh to 48 mesh.

Next, as a third embodiment, an example in which corn is crushed and classified to produce chicken feed will be described.

Regarding this embodiment, the granulation step is not required in the first embodiment shown in FIG. 1, and the only difference is the number of meshes of the sieve screen of the multi-stage sieve machine, so no drawings are particularly shown.

After supplying corn as a raw material to the grinding process and pulverizing it, in the particle size sorting process, a multi-stage sieve machine consisting of a 6-mesh sieve screen, a 16-mesh sieve screen, and a 22-mesh sieve screen is used to collect powder of 22 meshes or less. And ■6 mesh ~ 22
Classified into medium grains of mesh and coarse grains of 6 to 16 meshes.

The ratio of each component determined according to the palatability of the chickens was set in the proportion setting devices PB and PC to produce a corn mixed feed having a desired particle size composition ratio.

In the three examples above, the particle size structure of the final mixture rf7
．． e, the number of fractions is 2 or 3, but any number of particle size components can be obtained in any ratio in the present invention.

In that case, a number of classification means equal to the number of particle size components will be required.

As the classification means, in addition to the multi-stage sieve in the above embodiment, a conventional type such as an air classifier may be used.

Preferably, the proportional setter controlling the flow rate of each component stream can be variably set over a wide range.

In the present invention, as shown in the above embodiments, it is clear that the component flow serving as the reference for flow rate control is not limited to the component flow with the minimum particle size, but may be a component flow with any particle size.

Excess component streams other than the component streams used as standards for flow rate control are returned to the granulation process or returned to the particle size sorting process via the second pulverization process depending on the difference between the component streams. This makes it possible to continuously provide an accurate particle size composition ratio without requiring high-precision granulation and pulverization technology, and since there is no imbalance between component flows, it is possible to prevent the system from being unable to operate due to excess or deficiency. No situation arises.

The present invention can be applied to powders and granular mixtures having different particle size composition ratios, and is particularly useful in the fields of food industry, feed, cement, and pesticide manufacturing.

[Brief explanation of drawings]

Figure 1 of the attached drawings is a production system diagram of a flour mixture having a specific particle size composition ratio as an embodiment of the present invention, and Figure 2 is a production system diagram of a flour mixture having a specific particle size composition ratio as another embodiment of the present invention. FIG. Sl, S2. S3...Sieve, A, B, C, D
...Component flow, SFA, SFB, SFC, ...
...Screw feeder, MFA. MFB, MFC... Electromagnetic feeder, FA, F
B, FC...Flowmeter, PB, PC...
...Proportional setting device.

Claims (1)

[Claims for Utility Model Registration] An apparatus for producing a powder mixture having a predetermined particle size composition ratio by mixing each of a plurality of powder and granule components having a predetermined particle size range, the device producing a powder mixture having an arbitrary particle size distribution. a first pulverizing means for pulverizing a granular material raw material consisting of a granular material, and a plurality of classification devices for classifying the granular material pulverized by the first pulverizing means into a plurality of granular material components having a desired particle size range. means, and if necessary, when producing a powder mixture by mixing each of the plurality of powder and granule components, the amount of each of the plurality of powder and granule components mixed as the mixture; and In order to continuously correct the imbalance with the unmixed excess quantity, said first pulverization is carried out after granulating said excess quantity through a second pulverization means and by a granulation means according to the respective particle size. In an apparatus for producing a powder mixture, which also includes a means for returning the powder mixture to the classification means via a means, each of the plurality of powder components provided at the outlet of the classification means is continuously mixed for mixing. a flow meter for measuring the flow rate of each of the plurality of powder components, which is provided at an outlet of the feeding means; controlling and in response to the flow rate of any one of the plurality of powder or granule components, setting the flow rate of other powder or granule components to be mixed to a predetermined ratio with respect to the arbitrary one flow rate; and means for continuously mixing the arbitrary one powder component and the other powder components to be mixed according to a predetermined particle size composition ratio. A manufacturing device for a powder mixture.