JP7699189B2 - Microfabrication processing equipment - Google Patents

Description

The present invention relates to a microfabrication processing device.

In a variety of fields, including electronic components, chemical materials, food, pharmaceuticals, and chemistry, micronization processing equipment is used to micronize various substances such as metal particles and plant fibers. This micronization processing equipment generally includes a discharge means, such as a plunger pump, that applies high pressure to the suspension fluid, and a micronization processing means, such as a micronization nozzle or a micronization flow path that micronizes the substances contained in the suspension fluid.

Patent Document 1 discloses that the discharge means of the collision device must be selected depending on the presence or absence of solid matter to be pulverized. Specifically, it discloses that when the raw liquid is a slurry liquid containing solid matter, it is appropriate to use a hydraulic booster type ultra-high pressure pump that can move the plunger slowly from the perspective of device durability so that the pump is not damaged by the solid matter, and that for raw liquids that do not contain solid matter, it is not necessary to use a hydraulic device that can operate the plunger slowly, so a crank type plunger pump that rotates a crankshaft with an electric motor and converts it into reciprocating motion to operate the plunger is appropriate.

JP 2011-088108 A

However, the sliding speed of the cylinder head of the hydraulic booster type ultra-high pressure pump described in Patent Document 1 is low, with one reciprocating speed lasting several seconds, and for industrial-scale continuous micronization processing when the raw material liquid is a slurry liquid containing solids, it is essential to use a combination of multiple hydraulic booster type ultra-high pressure pumps. Therefore, since the high-pressure suspension fluid is discharged alternately from each hydraulic booster type ultra-high pressure pump at intervals of several seconds, the pressure fluctuation range of the discharged high-pressure suspension fluid is large, and in order to control these movements, it is necessary to introduce a proportional valve, a servo motor, etc. This pressure fluctuation causes damage or deterioration inside the ultra-high pressure parts, and wear of the seal parts of the cylinder head that slide at a low speed, and there are several problems.
In addition, hydraulic booster type ultra-high pressure pumps are generally large, so the entire micro-processing apparatus including the pump becomes large, requiring a large installation area and high implementation costs.

On the other hand, if a crank-type plunger pump is used when the suspension fluid is highly viscous or the fluid is a slurry containing solids, fibers, or powder, the high plunger drive speed of the crank-type plunger pump can cause poor suction of the raw liquid due to its viscosity, sedimentation, or coagulation when sucking in the raw material, creating a vacuum inside the cylinder and raising the risk of an explosion caused by the diesel effect at negative pressure.

In view of the above problems, the present invention aims to provide a micronization treatment device that is capable of micronizing a slurry fluid (hereinafter sometimes referred to as a suspension fluid) that has a high viscosity or contains solids, fibers, or powder, and that can prevent equipment damage caused by pulsation of the high-pressure suspension fluid.

Another object of the present invention is to provide a micro-processing apparatus that can reduce the energy consumption per unit of energy required for the micro-processing, stabilizes the pressure fluctuation range of the high-pressure suspension fluid discharged, and performs reliable micro-processing with a stable ultra-high pressure flow, thereby reducing the number of micro-processing steps and reducing costs.

The inventors have conducted extensive research to achieve the above object, and have found that even when performing micronization of a suspension, it is possible to suppress fluid pressure fluctuations in the suspension fluid and increase the amount of micronization per unit time by using a crankshaft drive system for the booster with a high plunger reciprocation speed, making the plunger move at high speed with regularity and periodicity, and by increasing the discharge pressure of the raw material supply pump to stably supply the suspension fluid to the booster.

That is, the present invention is a micronization processing apparatus comprising a raw material tank, a raw material supply pump, a raw material discharge pipe, a raw material suction pipe, a raw material return pipe and/or a raw material circulation pipe, a pressure booster, and a chamber equipped with a micronization processing means, in which the raw material supply pump and the raw material suction pipe are for pressurizing and supplying the raw material to the pressure booster, and the raw material circulation pipe and the raw material return pipe are for maintaining the pressure of the pressurized raw material at a high level while returning the excess to the raw material tank.

According to the micro-fining treatment device of the present invention, it is possible to perform micro-fining treatment on a slurry fluid having a high viscosity as a suspension fluid or containing solids, fibers, or powder, and it is possible to provide a micro-fining treatment device that can suppress equipment damage, etc. due to pulsation of the high-pressure suspension fluid.
Furthermore, the present invention provides a micro-processing apparatus that can suppress the energy consumption per unit time required for the micro-processing and can reduce costs by reducing the number of times the micro-processing is performed.

FIG. 1 is a conceptual diagram showing a micro-processing apparatus. FIG. 2 is a conceptual diagram showing a booster. FIG. 2 is a conceptual diagram showing a pump head of a booster. 4 is a graph showing pressure fluctuations in Example 1. 13 is a graph showing pressure fluctuations in Comparative Example 1. FIG. 2 is a conceptual diagram showing a wet grinding device. 1 is a graph plotting the transmittance measured in Example 4 and Comparative Example 3.

The microfabrication processing apparatus according to the present invention will be described in detail below. However, the following embodiments are intended to aid in understanding the invention and are not intended to limit the invention.

(Definition of terms)
The term "raw material" as used in this specification refers to a material used as a raw material for the micronization process, and refers to a material that is used in a slurry liquid containing the raw material and has a high viscosity, or a material that is used in a slurry liquid containing solids, fibers, or powder.
The term "micronization treatment" in this specification refers to the application of some kind of physical treatment to a raw material that has been brought to a high pressure state using a pressure intensifier.
In this specification, the term "processed liquid" refers to a liquid obtained after the raw material has been subjected to a micronization process, in other words, a raw material liquid that has passed through the micronization process apparatus of the present invention one or more times.

As shown in FIG. 1, the micronization processing apparatus 1 of this embodiment is mainly composed of a raw material tank 2 for storing raw material, a raw material supply pump 4, a raw material discharge pipe 3, a raw material circulation pipe 5, a raw material suction pipe 6, a raw material return pipe 7, a pressure booster 8, a chamber 10, a processing liquid tank 13, and a processing liquid return pipe 18.

Raw materials are supplied to and stored in the raw material tank 2. The raw material tank may be equipped with any of a variety of known stirring devices 23 to stir the raw materials. The raw material tank 2 is connected to the suction port of a raw material supply pump 4 via a raw material discharge pipe 3.

Examples of raw materials include starch powder, polyvinyl alcohol powder, dissolved cellulose powder, and the like, which have poor solubility and tend to form lumps and form highly viscous solutions, as well as cellulose fibers derived from polysaccharides contained in natural plants, such as wood fibers, bamboo fibers, sugarcane fibers, seed hair fibers, and leaf fibers, which require micronization, and chemically modified versions of these.
As other raw materials, the present invention can be appropriately used without particular limitation, for example, dispersion of toner, preparation of water-based paint, wet dispersion and crushing of organic/inorganic powders/colored pigment powders, etc. used in the chemical industry, wet dispersion and crushing of organic/inorganic powders used in the electronic parts industry, etc. It is particularly suitable for raw materials whose viscosity increases when they are made fine.

In addition, as a pretreatment for the micronization treatment described later, raw materials such as pulp that have been chemically modified can also be used as raw materials in this embodiment. Examples include hydrolysis of polysaccharides with an acid, hydrolysis of polysaccharides with an enzyme, swelling of polysaccharides with an alkali, oxidation of polysaccharides with an oxidizing agent, reduction of polysaccharides with a reducing agent, oxidation with a TEMPO catalyst, phosphate esterification, carbamate conversion, cationization, etc.

The raw material supply pump 4 is preferably a pump that can send the liquid without getting caught in solid matter in the suspension and can send the liquid even if the viscosity increases, and is preferably a positive displacement metering pump. Among positive displacement metering pumps, foreign matter such as contaminant powder can cause the injection nozzle to become clogged, so from the viewpoint of preventing this, a non-contact pump is preferable, and in particular, a bead pump, a tube pump, or a twin-axis screw pump are preferable.
It is also preferable to use various volumetric pumps whose upper limit of discharge pressure is 0.2 MPa to 10 MPa.
Furthermore, by setting the discharge pressure of each volumetric pump to at least 0.2 MPa, preferably 0.3 MPa, and more preferably 0.4 MPa or more, it becomes possible to prevent poor suction of the raw material liquid.

The raw material supply pump 4 is also connected to the raw material suction pipe 6, the raw material circulation pipe 5, and a pressure control valve (not shown). It is also possible to provide a switching valve (not shown) or the like to the raw material circulation pipe 5 and the raw material suction pipe 6 so that the liquid can be sent to one of them. By connecting in this way, the suspension fluid can be circulated between the booster 8 and the raw material tank 2. When using in this way, a pressure control valve (not shown) can be attached to the raw material circulation pipe 5 or the raw material return pipe 7, or the raw material circulation pipe 5 can be used without using the raw material return pipe 7. This reduces the number of places where the raw material stagnates, making the circulation even smoother.

By installing a pressure control valve (not shown), the pressure on the inlet side of the booster can be kept constant, stabilizing the operability of the microfabrication processing device according to the present invention. In addition, by monitoring the valve opening, abnormalities can be detected early. For example, if the nozzle becomes clogged, the valve opening tends to increase, and if the inside of the nozzle becomes worn, the valve opening tends to decrease.

The raw material circulation pipe 5 is connected to a product recovery pipe 21 for recovering the product after the micronization process has been performed a specified number of times, and the product recovery tank 21 is connected to a product tank 22. Although not shown, the product recovery pipe 21 may be connected to a cooler 17 and the product may be removed from the cooler, or of course the product may be removed from the chamber outlet pipe 12, in which case the product can be obtained at a high temperature.

The chamber 10 is equipped with a micronization means for carrying out the micronization process within the chamber. Examples of the micronization means include means for carrying out the micronization process by physical methods such as shear force or cavitation due to changes in pressure or speed, collision with a hard body for collision such as an impact ring, or mutual collision between high-pressure jets.

Hereinafter, a case where the microparticulation treatment is performed using a high-pressure jet nozzle as the microparticulation treatment means will be described.
A high-pressure injection nozzle 11 extending from and connected to the chamber supply ultra-high pressure pipe 9 is connected to the chamber 10, and the raw material is subjected to a micronization process in the chamber 10. In addition, a chamber outlet pipe 12, a processing liquid tank 13, a processing liquid discharge pipe 14, a processing liquid return pump 15, a cooler feed pipe 16, a cooler 17, and a processing liquid return pipe 18 can be connected to the chamber 10 depending on the number of times of micronization. By providing the processing liquid tank 13, the processing liquid discharge pipe 14, and the processing liquid return pump 15, the cooler 17 can be a highly efficient type cooler that applies exhaust pressure. In addition, since the exhaust pressure at the chamber outlet can be set to atmospheric pressure, the pressure difference at the nozzle outlet side becomes larger, and the processing efficiency of micronization can be improved.

The chamber outlet pipe 12 is used to take out the liquid after the raw material has been subjected to micronization treatment once or more times by the high-pressure spray nozzle 11 in the chamber 10 and store it in a treatment liquid tank 13 .
The processing liquid tank 13 is provided with a connection port (not shown) for connecting a processing liquid discharge pipe 14 and a processing liquid return pump 15 .
The processing liquid tank 13 and the head tank 19 are connected using a processing liquid discharge pipe 14, a processing liquid return pump 15, a cooler feed pipe 16, a cooler 17, and a processing liquid return pipe 18, and are connected so as to be able to send the liquid after the micronization process to the head tank 19. A discharge valve 24 and a discharge pipe 20 are connected to the head tank 19, and by opening and closing the discharge valve 24, it is possible to instantly return the processing liquid to the raw material tank 2 at any desired timing without requiring energy.
The treatment liquid return pump 15 is preferably a pump that can send the suspension without getting solid matter caught in it, similar to the raw material supply pump 4, and can send the suspension even if the viscosity increases.
The cooler 17 is for lowering the temperature of the treatment liquid, and may be disposed between the outlet of the chamber 10 and the inlet of the raw material tank 2, or may be disposed in the raw material circulation pipe 5, and the installation position is not limited. The raw material temperature can also be controlled by adjusting the temperature and flow rate of the cold water sent to the cooler 17. Moreover, by using hot water instead of the cooling water or adding a heating device, the micronization treatment can also be performed in a heated state.
In addition, the outlet of the chamber outlet piping 12 may be connected to the inlet of the cooler 17, eliminating the need to provide the treatment liquid tank 13, treatment liquid discharge piping 14, treatment liquid return pump 15, and cooler feed piping 16, and further, the treatment liquid return piping 18 may be connected to the outlet of the chamber 10 to return the treatment liquid directly to the raw material tank 2.

The raw material, which has been made into a high-pressure state by the pressure booster 8, is sent from the chamber supply ultra-high pressure pipe 9 to the high-pressure injection nozzle 11. The sent raw material is injected from the high-pressure injection nozzle 11 at a high pressure of 30 to 250 MPa to form an injection stream, and this injection stream is suddenly and simultaneously lowered in pressure to cause cavitation, collisions between the injection streams, and collisions with hard objects, thereby homogenizing or pulverizing the raw material. The high-pressure injection nozzle 11 may be a known high-pressure injection nozzle made of ceramics, diamond, sapphire, or the like, capable of injecting a high-pressure fluid.
Here, the micronization treatment of the raw material may be carried out multiple times on the solid matter in the raw material. That is, the treatment liquid obtained in the chamber 10 may be sent to the raw material tank 2 using the treatment liquid discharge pipe 14 or the like, and then the micronization treatment may be carried out again in the chamber 10. The second micronization treatment is called 2-pass.

Micronization is more likely to proceed when multiple high-pressure injection nozzles 11 are connected to the chamber 10 and the injection flows collide at an angle of collision θ, and when two nozzles are used, the angle θ is preferably 95 to 178°, particularly 100 to 170°. If the angle is less than 95°, for example, when the nozzles collide at a right angle of 90°, the collision dispersion is structurally more likely to collide directly with the wall of the chamber in some parts, and there are many cases where the polymerization degree decreases by more than 10% even after one micronization.
On the other hand, when the angle is greater than 178°, for example when the collision is 180°, that is, when the particles are collided head-on, the effect of the atomization is increased, but the nozzle on the other side and the surrounding equipment may be damaged. When three nozzles are used, the angle θ is set to 120°, which can maximize the collision efficiency while suppressing damage to the nozzle and surrounding equipment.

When the micronization process is carried out multiple times, the number of times can be adjusted as desired within the range of approximately 2 to 200 times. When a slurry liquid containing long fiber raw materials is used as the raw material, the properties of the resulting treated liquid become smoother and more homogeneous the more the process is repeated, the finer the solids in the liquid become, and the thinner and shorter the fibers in the liquid become. Therefore, it is possible to carry out the micronization process repeatedly the number of times appropriate for the application.

The crank-driven intensifier 8 will be described with reference to the structural diagram of Fig. 2. Fig. 2 shows an intensifier having three plungers, but the number of plungers may be one, two, or four or more depending on the purpose of treatment and the installation location. In addition, for the purpose of suppressing pulsation, it is preferable that the number of plungers is three or more.
The intensifier 8 includes a crank portion 81 and a pump head 82 .

The crank section 81 includes a crankshaft 83 and a power source 35. The crankshaft 83 is composed of a crankshaft 30 and crank pins 31a, 31b, and 31c that are arranged with a phase shift of 120 degrees from one another in the rotational direction.
A journal 36 is connected to the power 35, and a main gear 33 is engaged with the journal 36. In addition, a meshing gear 32 is engaged with a crank journal 34, and the meshing gear 32 and the main gear 33 are disposed so as to mesh with each other. In this manner, the crankshaft 83 can be rotated by the driving force of the power 35. The power 35 can be an inverter motor. In this manner, the rotation speed of the crankshaft can be easily changed, and the discharge amount required for the micronization process can be controlled.

The crankshaft 83 is connected to the connecting rods 29a, 29b, and 29c via connecting rod connecting shafts (not shown) which are connected to the crank pins 31a, 31b, and 31c, respectively.
Furthermore, plungers 27a, 27b, 27c are connected to the connecting rods 29a, 29b, 29c by connecting pins 28a, 28b, 28c.

When the crankshaft 83 rotates in the direction of the arrow R, the connecting rods 29a, 29b, 29c swing, causing the plungers 27a, 27b, 27c to reciprocate in the direction of the arrow S.
Here, the plunger reciprocating speed at this time is determined by the gear ratio of the meshing gear 32 and the main gear 33, so by appropriately setting these combinations or by changing the rotation speed of the power 35, the plunger reciprocating speed can be set to any range. The plunger reciprocating speed can be appropriately set according to the discharge pressure value of various volumetric metering pumps. In the present invention, it is preferable to set the plunger reciprocating speed to 60 times/minute or more. Considering production efficiency, 100 times/minute or more is preferable, and 200 times/minute or more is even better. In order to suppress pulsation and further stabilize the equipment, 300 times/minute or more is even better. Also, if it is 1,000 times/minute or more, it is not preferable because the supply pressure needs to be increased to a level higher than the capacity of the general-purpose pump, and 1,000 times/minute or less is preferable, and 800 times/minute or less is even more preferable.

By eccentrically connecting the connecting rods 29a, 29b, and 29c to the crank pins 31a, 31b, and 31c, respectively, the timing of pressurizing and discharging the suspended fluid can be shifted, stabilizing the discharge pressure and improving the efficiency of the atomization process. Therefore, the movement of the plunger describes a sine curve, and pulsation of the discharge pressure of the booster can be suppressed. In addition, it is possible to accurately control the movement of the phase difference, and it becomes possible to reproduce the overlap of the sine curves.

The pump head 82 connected to the top of the crank section 81 has a communication port 25 for supplying the suspension fluid from the raw material tank 2 into the pump head 82 using the raw material supply pump 4. In addition to the communication port 25, a connection port (not shown) is provided for discharging the suspension fluid and returning it to the raw material tank 2. A raw material return pipe 7 is connected to the connection port. High pressure suspension fluid is supplied from inside the pump head 82 to the chamber supply ultra-high pressure pipe 9.

The pump head 82 will be described with reference to the structural diagram of Fig. 3. The pump head 82, which is connected to the top of the crank portion 81, is provided with a pressure chamber 37, a high-pressure side check valve 45 consisting of a valve seat 39, a spring 38, and a ball 40, a low-pressure side check valve 46 consisting of a valve seat 43, a spring 44, and a ball 42, a suction chamber 41, a raw material supply low-pressure flow path 47, and a raw material discharge high-pressure flow path 48.
The low pressure side check valve 46 and the piston seal assembly 26 are connected, and a space is formed between them in which the supplied suspended fluid is filled, and the pressure chamber 37 is connected to the chamber supply ultra-high pressure piping 9.

The flow of the raw material inside the pump head 82 is shown in Figure 3, and is specifically shown below in terms of the up-down relationship on the figure. The piston seal assembly 26 in which the plunger 27 is housed is disposed in the sliding direction of the plunger 27. When the plunger 27 stops rising upward inside the piston seal assembly 26 and starts to be pulled downward, the ball 40 moves down due to the force of the spring and the pressure of the pressure chamber 37, closing the gap, and the ball 42 moves down and opening the gap, and as the plunger 27 moves down due to the pushing pressure of the raw material supply pump 4, the suspended fluid is rapidly sucked into the space inside the piston seal assembly 26 from the suction chamber 41 via the raw material supply low-pressure flow path 47 (Figures 3(i) to (ii)).
Next, the suspension fluid is sucked in through the raw material supply low pressure flow path 47, and as the plunger 27 descends to the bottom inside the piston seal assembly 26 and then begins to rise, the spring force and the pressure inside the piston seal assembly 26 cause the ball 42 to rise and close the gap. Next, when the pressure rises to the discharge pressure and becomes higher than the pressure chamber 37, the ball 40 rises, the gap opens, and the suspension fluid is discharged into the pressure chamber 37 through the raw material discharge high pressure flow path 48 (FIGS. 3(ii) to (iii)). The pressurized and discharged suspension fluid is sent under high pressure to the high pressure injection nozzle 11 through the chamber supply ultra high pressure pipe 9.

The micronizing apparatus according to the present invention having the above-mentioned configuration has the following advantages: A specific example will be described below in which pulp containing long fibers is used as the raw material.
The pulp-containing suspension can be kept in a state of flowing in the raw material circulation path by circulating between two paths, namely, the path between the raw material tank 2, raw material discharge pipe 3, raw material circulation pipe 5, and raw material tank 2, and the path between the raw material discharge pipe 3, raw material suction pipe 6, pressure booster 8, and raw material return pipe 7. By keeping it in this state, it is possible to prevent the pulp mixture liquid from stagnating and settling in the path, which would cause the pulp concentration to increase, and to eliminate malfunctions at the beginning of production and during production.

In addition, in the process of returning the processing liquid discharged from the chamber 10 to the raw material tank 2 and carrying out multiple refining processes, even if the viscosity gradually increases due to the refining of the pulp, the raw material is circulated through the above two routes at a constant flow rate or higher, and the thixotropy of the raw material itself allows the liquid to be maintained in a flowing state with low viscosity, making it possible to stably carry out the fiber refining process.

The present invention will be described below based on examples, but the present invention is not limited to these examples. In addition, the particle size distribution described in the examples and comparative examples was measured by the following measurement method.

(Particle size distribution measurement)
The particle size distribution of the dispersion after the micronization treatment was measured by the following measurement method.
Each sample was placed in a 50 ml centrifuge tube and purified water was added to prepare 40 g of a 0.1% fine cellulose fiber dispersion. The tip of a homogenizer (Ultra Turrax T18 manufactured by IKA) was then inserted into the centrifuge tube up to the 25 ml mark, and the mixture was stirred at 10,000 rpm for 3 minutes before measurement.
The particle size distribution measuring device used was Mastersizer 3000 (manufactured by Malvern Panalytical).
The stirring speed of the particle size distribution measuring device was set to 3,000 rpm, and the background measurement was performed, followed by adding the sample. After the sample was added, the sample was measured 30 seconds later. After five measurements were completed, the device was cleaned, and the next sample was measured in the same manner. The average value of the five measurements was used as the "volume distribution" data.

Example 1
Using the refining treatment apparatus according to the present invention shown in Figure 1, the refining treatment was carried out with bamboo pulp having a solid concentration of 2% as the raw material at a discharge pressure of 0.35 MPa for the raw material supply pump, a pressure of 200 MPa, and a plunger reciprocating speed of 400-500 times/min by inverter control. During this treatment, the pressure fluctuation was measured using a pressure gauge placed on the inlet side of the chamber. Note that repeating the refining treatment is called a pass, and repeating X times is called Xpass. The results of the pressure fluctuation measurement over one minute of the measurement time are shown in Figure 4.

(Comparative Example 1)
The pressure booster 110 in the wet grinding apparatus shown in Figure 6 was replaced with a hydraulic booster type ultra-high pressure pump, and the milling process was carried out at a pressure of 180 MPa using softwood pulp with a solid concentration of 2% as the raw material. At that time, the pressure fluctuation was measured using a pressure gauge placed on the inlet side of the chamber. The results of the pressure fluctuation measurement for one minute during the measurement time are shown in Figure 5. The reciprocating speed of the plunger was 10-25 times/minute.

According to the graph shown in FIG. 4, the average injection pressure in Example 1 was 200.19 MPa, the standard deviation was ±2.39 MPa, the pressure range was about 15 MPa, and the pressure fluctuation range was about 8%.
In addition, according to the graph shown in Figure 5, the average injection pressure in Comparative Example 1 was 176.11 MPa, the standard deviation was ±7.51 MPa, the pressure range was about 30 MPa, and the pressure fluctuation range was about 17%. It is considered that when the pressure fluctuation range is large, there is a high risk of damage to the equipment such as each stand, each pipe, chamber, and high-speed injection nozzle. Furthermore, as a secondary effect, in Example 1, the power consumption per pass was reduced by 37% compared to Comparative Example 1.

Example 2
Using the micronization treatment apparatus according to the present invention shown in Figure 1, the discharge pressure of the raw material supply pump was set to 0.35 MPa, and the micronization treatment was carried out for 25 passes using bamboo pulp with a solid concentration of 1.20% as the raw material at a pressure of 200 MPa and a plunger reciprocation speed of 400-500 times/min. In the micronization treatment, particle size distribution was measured for the dispersion at the 20th and 25th passes, and the volume-based average diameter and specific surface area were measured. The results are shown in Table 1 together with the time required for the micronization treatment.

Example 3
Using the micronization treatment device used in Example 2, the discharge pressure of the raw material supply pump was set to 0.75 MPa, and the micronization treatment was performed 35 times using bamboo pulp with a solid concentration of 1.25% as the raw material at a pressure of 200 MPa and a plunger reciprocation speed of 400-500 times/min. In the micronization treatment, particle size distribution was measured for the dispersion liquid at 20 passes, 25 passes, and 35 passes, and the volume-based average diameter and specific surface area were measured. The results are shown in Table 1 along with the time required for the micronization treatment. In addition, since the treatment liquid becomes smoother as the number of repetitions increases, it is possible to operate without problems even if the discharge pressure of the raw material supply pump is lowered, and it was confirmed that operation is possible even at 0.30 MPa.

Example 4
Using the micronization treatment device used in Example 2, the discharge pressure of the raw material supply pump was set to 0.54 MPa, and the micronization treatment was performed for 25 passes using bamboo pulp with a solid concentration of 1.19% as the raw material at a pressure of 200 MPa and a plunger reciprocation speed of 400-500 times/min. In the micronization treatment, particle size distribution was measured for the dispersion at the 23rd and 25th passes, and the volume-based average diameter and specific surface area were measured. The results are shown in Table 1, along with the time required for the micronization treatment.

(Comparative Example 2)
Using the wet grinding apparatus used in Comparative Example 1, bamboo pulp with a solid concentration of 1.19% was used as the raw material for the micronization treatment at a pressure of 200 MPa for 50 passes. The particle size distribution of the dispersion at the 50-pass point in the micronization treatment was measured, and the volume-based average diameter and specific surface area were measured. The results are shown in Table 1, along with the processing time per liter required for the micronization treatment. The reciprocating speed of the plunger was 15-25 min ^-1 .

From the results of Comparative Example 2 in Table 1, in the case of the wet-type grinding apparatus using the hydraulic booster type ultra-high pressure pump, the number of repeated processes required to reduce the volume-based arithmetic mean diameter to 2.5 μm or less was 50 times.
On the other hand, when the micro-pulverization treatment device according to the present invention was used, the number of micro-pulverization treatments was roughly half that of the wet-type pulverization device using a hydraulic booster-type ultra-high pressure pump, and the volume-based arithmetic mean diameter was 1.5 μm.
From this result, it became clear that the time required for the micronization processing apparatus according to the present invention can be reduced by half or more. In addition, when the power consumption rate required for one pass was reduced by 37% to 63%, it became clear that the power consumption could be reduced by 63% x 0.5 = 31.5%, which is a significant reduction of 68.5%. In addition, since the pressure fluctuation width can be suppressed, it is considered that the reproducibility of the micronization processing can be improved.

In the hydraulic booster type ultra-high pressure pump system, the piston reciprocating speed is slow, and it is considered to be in the boundary lubrication state on the Stribeck curve, or near the border between the boundary lubrication state and the mixed lubrication state. Therefore, the load increases when the piston slides, and the power consumption rate required for one pass becomes large.
In this regard, it is considered that the plunger reciprocation speed of the crankshaft type intensifier is fast, and the plunger slides in the fluid lubrication zone of the Stribeck curve. Therefore, it is possible to reduce the size of the motor required for driving, and as a result, the size of the micro-processing device itself can also be reduced.

Example 5
In the micronization treatment of Example 4, the transmittance of the treatment solution obtained in each of the treatments of 1 pass to 25 passes was measured using an ultraviolet-visible spectrophotometer (U-3900, manufactured by Hitachi High-Technologies Corporation). A graph in which each value is plotted is shown in FIG.

(Comparative Example 3)
In the micronization treatment of Comparative Example 2, the transmittance of the treatment solution obtained in each of the treatments from 1 pass to 50 passes was measured using an ultraviolet-visible spectrophotometer (U-3900, manufactured by Hitachi High-Technologies Corporation). A graph in which each value is plotted is shown in FIG.

The graph in Figure 7 shows that Example 4 has a higher transmittance in each pass, and that even with the same number of processing steps, the micro-finishing process performed using the micro-finishing process device according to the present invention is able to achieve finer micro-finishing.

1: Micronization treatment device, 2: Raw material tank, 3: Raw material discharge pipe, 4: Raw material supply pump, 5: Raw material circulation pipe, 6: Raw material suction pipe, 7: Raw material return pipe, 8: Pressure booster, 9: Chamber supply ultra-high pressure pipe, 10: Chamber, 11: High pressure spray nozzle, 12: Chamber outlet pipe, 13: Treatment liquid tank, 14: Treatment liquid discharge pipe, 15: Treatment liquid return pump, 16: Cooler feed pipe, 17: Cooler, 18: Treatment liquid return pipe, 19: Head tank, 20: Discharge pipe, 21: Product recovery pipe, 22: Product tank, 23: Agitator, 24: Discharge valve, 25: Communication port, 26: Piston seal assembly, 27: Plunger, 28: Connecting pin, 29: connecting rod, 30: crankshaft, 31: crank pin, 32: meshing gear, 33: main gear, 34: crank journal, 35: power, 36: journal, 37: pressure chamber, 38: spring, 39: valve seat, 40: ball, 41: suction chamber, 42: ball, 43: valve seat, 44: spring, 45: high pressure side check valve, 46: low pressure side check valve, 47: raw material supply low pressure flow path, 48: raw material discharge high pressure flow path, 81: crank portion, 82: pump head, 83: crankshaft, 107: chamber, 108: high pressure injection nozzle, 109: tank, 110: pressure booster, 111: heat exchanger

Claims (2)

At least a raw material tank, a raw material supply pump,
A raw material discharge pipe, a raw material suction pipe, a raw material return pipe, and/or a raw material circulation pipe;
A crank-driven intensifier with a plunger reciprocating speed of 60-1000 times/min ;
A chamber equipped with a micro-processing means;
A micronization treatment apparatus having a treatment liquid return pipe ,
the raw material supply pump and the raw material suction piping are connected to the raw material tank and the raw material discharge piping, the raw material supply pump is connected to the raw material suction piping, and the raw material suction piping is connected to the booster, in order to supply the raw material under pressure to the booster ;
the raw material circulation pipe and the raw material return pipe are connected to circulate the raw material between the booster and the raw material tank ,
The processing liquid return pipe is for returning the processing liquid that has been subjected to the micronization treatment from the chamber to the raw material tank . The raw material supply pump supplies the raw material to the pressure booster at a pressure of 0.2 MPa or more and 10 MPa or less.
The microfabrication processing apparatus according to claim 1 .

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