Refinement treatment device for fiber-containing mixture

Abstract

To provide a refinement treatment device for a fiber-containing mixture that can maintain the fiber-containing liquid in the refinement treatment device for the fiber-containing mixture in a flowing state and enables stable fiber refinement.SOLUTION: A refinement treatment device for a fiber-containing mixture includes at least a raw material tank, a raw material circulation pump, a pressure booster, a raw material circulation path comprising a raw material supply pipe, a liquid supply side check valve and a raw material return pipe, a chamber supply high-pressure path comprising a chamber supply high-pressure pipe and a high-pressure side check valve, and a chamber comprising refinement treatment means. The raw material return pipe is configured to return the raw material to the raw material tank.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a fiber-refining treatment apparatus for refining a mixed liquid containing fibers. [Background technology]

[0002] Fibers have a wide variety of properties depending on the type, and can be broadly categorized into natural fibers and chemical fibers. Natural fibers include those that exist naturally, such as cotton, hemp, silk, and wool, as well as pulp obtained from fibers that make up wood and grass. Chemical fibers are fibers that have been artificially and chemically created by humans, and can be divided into regenerated fibers, semi-synthetic fibers, synthetic fibers, and inorganic fibers depending on the raw materials used.

[0003] Among natural fibers, products that address environmental issues such as global warming have been in demand in recent years, and attention has been focused on those with a low environmental impact. For example, there are fibers derived from polysaccharides in which glucose, which is most abundant on Earth as a component of the plant cell walls of woody plants such as broad-leaved and coniferous trees, and herbaceous plants such as bamboo, reeds, and sorghum, is linked in a straight chain by β1-4 bonds. As a fiber derived from this polysaccharide, pulp is known that is mass-produced at paper pulp factories using raw materials such as wood and bamboo derived from coniferous and broad-leaved trees, and its main component is cellulose. Cellulose is also known as a component of some animals, such as sea squirts, and as a component of nata de coco, which is produced by some fungi, such as acetic acid bacteria.

[0004] On the other hand, it is known that fibers can be made into materials with excellent properties such as high strength, high elasticity, and low thermal expansion coefficient by miniaturizing the fiber width. In order to enhance this characteristic, fibrillation, which is a process in which the fiber surface is made fluffy and entangled, is being carried out. Here, fibrillation is understood to mean fuzzing or splintering caused by friction of the fiber, and occurs when the small fibers that make up the fiber, the "fibrils," are rubbed and become fluffy. In the textile industry, this phenomenon, called whitening caused by fibrillation, in which the light reflection changes and the product appears whitish, is considered to be a poor appearance of the product, but as the movement to use fibers in various industries spreads, fibrillation is being carried out as a method to utilize the functions of fibers. It is expected that fibrillation will provide functions such as reinforcement by entanglement of fibers, adsorption of various components by increasing the specific surface area, transparency by reducing diffuse reflection of light, smoothing of the surface, and improvement of the feel.

[0005] Regarding fiber fineness treatment methods and fineness treatment devices, various fineness treatment methods and fineness treatment devices, including the manufacturing method described in Patent Document 1, have been studied.

[0006] Patent Document 1 discloses an apparatus for finely processing a mixture of materials containing fibers, the apparatus comprising at least one discharge section having an outlet for a flow path of the fiber mixture, at least one supply device for supplying the fiber mixture to the discharge section at a predetermined processing pressure, at least one positioning device for positioning the discharge section, and a movable processing member for decomposing the fiber mixture, the apparatus being provided opposite the discharge section, and a slit-shaped processing area being formed on the flow path of the fiber mixture that has passed through the discharge section, between the partial surface of the movable processing member with which the fiber mixture collides and the discharge section. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Special Publication No. 2021-517212 Summary of the Invention [Problem to be solved by the invention]

[0008] Fibers have properties such as having their own specific gravity and being insoluble in liquid. Due to these properties, fibers in a mixed liquid containing fibers separate and settle due to the difference in specific gravity, but this separation and settling time varies depending on the raw material from which the fibers are derived or the fiber width and fiber length of the fibers. In addition, fibers do not completely dissolve in liquid, so the fibers in a mixed liquid containing fibers are in a state of being dispersed in the liquid. Therefore, during the fiber refining process, sedimentation can be prevented in areas where the fiber-containing mixed liquid can be kept in a fluid state. On the other hand, in areas where it is difficult to keep the fiber-containing mixed liquid in a fluid state, such as the end of a pipe, the fibers may settle and form a thick aggregate layer, making it difficult to perform a stable fiber refining process. This is particularly likely to be the case with fibers with a large aspect ratio that tend to become entangled with each other and form a cocoon-like shape. The aspect ratio is the value obtained by dividing the length of the fiber by the width of the fiber. If the aspect ratio is higher than 50, the entanglement will be strong, and if it exceeds 100, it will be noticeable.

[0009] In addition, a pressure intensifier may be used in one step of the fiber-containing mixed liquid microparticulation process, and a check valve using a spring inside may be used on either the suction side or the discharge side or on one side of the pressure intensifier to control the flow direction of the fiber-containing mixed liquid. When this type of check valve is used, fibers are likely to become tangled in the spring. Furthermore, if fibers become tangled in the spring, the check valve will not move well and the non-return function will be lost, or the tangled fibers will accumulate and block the flow path, narrow the flow path, or close the flow path completely. Furthermore, the fibers tangled in the spring will become knots, which may come off (fall off) from the spring and flow into the subsequent process, clogging the path in the subsequent process, making it impossible to perform a stable fiber fine processing.

[0010] Furthermore, in one step of the fiber-containing mixed liquid micro-refining process, a pressure intensifier and a high-pressure injection nozzle may be used. Here, the pressure intensifier is used to pressurize and compress the fiber-containing mixed liquid by sucking and discharging it at a constant alternating timing, and to send it to the next process. Therefore, there are times when the fiber-containing mixed liquid does not flow and remains near the suction side of the pressure intensifier. Even if this lasts for a few seconds, when a fiber-containing mixed liquid with a relatively large fiber width is micro-refined, the fibers may settle and become large fuzzball-like or cocoon-like lumps. When this happens, the lumps are sucked into the pressure intensifier while twisting, and are sent to a high-pressure injection nozzle with a finer diameter through a very narrow high-pressure path. The pressurized and compressed cocoon balls become very hard during this process, which can cause blockages on the inlet side or inside of the high-pressure injection nozzle, making it difficult to perform stable fiber micro-refining.

[0011] The manufacturing apparatus described in Patent Document 1 can improve the quality and homogeneity of the processed fiber mixture by feeding at least a part, or even the entire amount, of the processed fiber mixture back to the apparatus to repeatedly process the fiber mixture. In this case, it is described that a circulation system between the collection tank and the supply unit can be very simply used to achieve a predetermined fiber diameter and / or fiber length distribution. Furthermore, it is described that clogging can be minimized by tilting or bending the movable processing member. However, as mentioned above, the properties of the fibers in the fiber mixture, such as separation and settling time, vary depending on the raw material from which the fibers are derived, and furthermore, adjusting the gap with a movable processing member to prevent clogging can lead to deterioration in quality. Therefore, there is room for further improvement in order to perform stable fiber fine-finishing processing.

[0012] Therefore, the present invention aims to provide a micro-refining treatment device that can make the mixed liquid in the micro-refining treatment device flow even when a mixed liquid containing fibers of various origin components is used, and that can ensure stable quality through stable micro-refining treatment. [Means for solving the problem]

[0013] As a result of extensive research into achieving the above-mentioned object, the inventors have discovered that the flow direction of the liquid can be controlled by using hard balls with a high specific gravity and by utilizing the pressure of the liquid itself, which has been made high pressure by a pressure booster, and that the above-mentioned problems can be solved by providing a path for preventing the separation and sedimentation of fibers in the raw material.

[0014] That is, the present invention is an apparatus for micronizing a mixed liquid containing fibers, comprising at least a raw material tank, a raw material circulation path having a raw material tank, a raw material circulation pump, a booster, a raw material supply pipe, a feed side check valve, and a raw material return pipe, a chamber supply high pressure path having a chamber supply high pressure pipe and a high pressure side check valve, and a chamber having a micronizing means, wherein the raw material return pipe is for returning the raw material to the raw material tank. Effect of the Invention

[0015] According to the present invention, even when a mixed liquid containing fibers of various origin components is used, the mixed liquid in the fine-fining processing device can be made to flow, and a stable fine-fining process can be performed to ensure stable quality. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a schematic diagram of a fiber-containing mixed liquid microparticulation treatment device according to the present invention. [Diagram 2] FIG. 2 is a conceptual diagram of a pressure intensifier used in the fiber-containing mixed liquid microparticulation treatment device according to the present invention. [Diagram 3] FIG. 3 is a basic conceptual diagram of a liquid supply side check valve, a high pressure side check valve, and a booster supply piping used in the fiber-containing mixed liquid microparticulation treatment device according to the present invention. [Figure 4]FIG. 4 is a diagram showing the state of each check valve when the fiber-containing mixed liquid refinement treatment device of the present invention is stopped (a), when the pressure intensifier 6 is sucking in the raw material (b), and when the pressure intensifier 6 is discharging the raw material (c). [Diagram 5] Figure 5 shows electron microscope photographs of ground cotton and cotton after micronization. [Figure 6] FIG. 6 is a conceptual diagram of a conventional microfabrication processing apparatus. [Figure 7] FIG. 7 is a graph showing the settling height test results over time. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] The fiber-containing mixed liquid microparticulation treatment apparatus of the present invention will be described below. However, the following embodiments are intended to aid in understanding the invention and are not intended to limit the invention.

[0018] (Definition of terms) In this specification, the term "raw material" refers to a mixture containing fibers used as a raw material for fiber refining. 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 "treatment liquid" refers to the liquid after the raw material has been subjected to a microparticulation treatment.

[0019] As shown in FIG. 1, the fiber-containing mixed liquid micro-refining treatment device 1 of this embodiment is mainly composed of a raw material tank 2 for storing the raw material, a raw material circulating pump 3, a raw material circulating path 4, a chamber supply high-pressure path 5, multiple pressure intensifiers 6, and a chamber 8.

[0020] Raw materials are supplied to and stored in the raw material tank 2. The raw material tank may be equipped with various known stirring devices (not shown) to stir the raw materials. The raw material tank 2 is connected to the suction port of a raw material circulating pump 3 via a raw material withdrawal pipe 9.

[0021] Examples of raw materials include cellulose fibers derived from polysaccharides containing natural plants, such as wood fiber, bamboo fiber, sugarcane fiber, seed hair fiber, and leaf fiber; pellicle, a gel-like substance made of 100% cellulose derived from bacterial cellulose (polysaccharide) produced by microorganisms such as acetic acid bacteria; chemical pulp, mechanical pulp, and waste paper made from woody plants such as broad-leaved trees and coniferous trees, and herbaceous plants such as bamboo and reeds; and crop residues derived from the leaves, flowers, stems, roots, and skins of plants, such as bagasse, rice straw, used tea leaves, and fruit juice residue.

[0022] In addition, a raw material such as pulp that has been chemically modified as a pretreatment for the microfining treatment described below can also be used as the raw material in this embodiment. Examples of such pretreatment 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 formation, cationization, etc.

[0023] The raw material circulating pump 3 is preferably a pump that can send the fiber-containing mixed liquid without getting the fibers caught in it, 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.

[0024] The raw material circulation path 4 includes a raw material supply pipe 10, a liquid supply side check valve 11, and a raw material return pipe 12, which will be described later. The raw material supply pipe 10 connects the raw material circulation pump 3, each liquid supply side check valve 11, and the raw material return pipe 12 to supply raw material to the pressure booster 6. The raw material supply pipe 10 is provided with a branch 13a for connecting to the liquid supply side check valve 11. The branch 13a and the liquid supply side check valve 11 may be connected using a pipe such as a T-shaped pipe integrated with the raw material supply pipe 11, or the branch 13a and the liquid supply side check valve 11 may be connected using a separate pipe. In this case, it is preferable to shorten the distance from the branch 13a to the liquid supply side check valve 11. It is also preferable to install the liquid supply side check valve 11 so that the liquid supply side check valve 11 is approximately perpendicular to the floor surface. In addition, it is preferable to connect the branch point 13a and the feed side check valve 11 so that the distance between them can be within 3 m, preferably within 1 m, and more preferably within 0.5 m. In addition, it is preferable to set the flow rate of the fluid in the raw material supply pipe 10 in the raw material circulation path 4 to 0.5 m / min or more. In addition, it is preferable to position the branch point 13a in the height direction at the lowest part of the flow path from the branch point 13a to the check valve 11. In this way, the flow of the raw material supply pipe 10 always eliminates the accumulation of raw material. In addition, it is preferable to position a part of the flow path height on the rear side of the branch point 13a of the raw material supply pipe 10 higher than the height of the check valve 11. An air vent may be provided in this part. In this way, it is preferable to prevent air from being sucked into the booster when air is entrained in the mixed liquid containing fibers.

[0025] The raw material return pipe 12 is connected at one end to the raw material supply pipe 10, and at the other end to the raw material tank 2 using a pipe joint or the like (not shown) so that the raw material can be returned. By connecting in this manner, it is possible to return a part of the mixed liquid containing fibers to the raw material tank 2 through the raw material return pipe 12 while supplying a part of the mixed liquid containing fibers to the booster 6 through the raw material supply pipe 10, and the raw material can be always flowed without remaining in the raw material circulation path 4. Here, the raw material supply pipe 10 is a pipe provided with the branch portion 13a, and the raw material return pipe 12 is a pipe not provided with the branch portion 13a, and the two are distinguished from each other. Of course, the raw material supply pipe 10 and the raw material return pipe 12 can be made into a single pipe. In this case, for convenience, the pipe with the branch portion 13a is distinguished as the raw material supply pipe 10, and the pipe without the branch portion 13a is distinguished as the raw material return pipe 12.

[0026] An automatic adjustment valve (not shown) may be installed in the flow path of the raw material return pipe 12, and a pressure gauge or the like (not shown) may be installed between the raw material circulation pump 3 and the raw material supply pipe 10. By applying pressure to the raw material supply pipe 10, it is possible to facilitate the feeding of the raw material into the intensifier 6 through the liquid supply side check valve 11, and to assist in preventing the treatment liquid chamber 22 from becoming negative pressure. It is possible to prevent the occurrence of an explosion due to the diesel effect caused by the negative pressure, which would result in scorching or elution of the sealing parts inside the intensifier. These devices make it possible to keep the raw material supply pressure constant, and the operability of the fiber-containing mixed liquid micronization treatment device according to the present invention is stabilized. In addition, early detection of abnormalities is possible by monitoring the valve opening and the pressure in the raw material circulation path.

[0027] The chamber supply high pressure path 5 includes a chamber supply high pressure pipe 15 and a high pressure side check valve 14. The high pressure side check valve 14 is connected to the chamber supply high pressure pipe 15, and the chamber supply high pressure pipe 15 is connected to the chamber 8. The chamber supply high pressure pipe 15 includes a branch portion 13b for connecting the high pressure side check valve 14. It is also preferable to install the high pressure side check valve 14 approximately perpendicular to the floor surface. The chamber supply high pressure pipe 15 is formed of a pressure resistant material such as stainless steel.

[0028] The chamber 8 is equipped with a micronization means for carrying out a 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.

[0029] 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 16 extending from and connected to the chamber supply high-pressure pipe 15 is connected to the chamber 8, and the raw material is subjected to a micronization treatment in the chamber 8. In addition, a treatment liquid return pipe 17 and / or a treatment liquid recovery pipe 18 can be connected to the chamber 8 depending on the number of times of micronization treatment. The processing liquid return pipe 17 is for returning (transporting) the liquid after the raw material is processed one or more times by the high-pressure spray nozzle 16 in the chamber 8 to the raw material tank 2. Therefore, when the micronization process is performed only once, the processing liquid return pipe 17 does not need to be connected. On the other hand, the treated liquid recovery pipe 18 is for sending the liquid after the raw material has been treated one or more times by the high-pressure spray nozzle 16 in the chamber 8 to the product tank 19. In addition, a heat exchanger (not shown) for cooling the processing liquid may be connected to the processing liquid return piping 17 and the processing liquid recovery piping 18 to cool the processing liquid when it is delivered to the raw material tank 2 and / or when it is delivered to the product tank 19.

[0030] The raw material, which has been made high-pressure by the pressure booster 6, is sent from the chamber supply high-pressure pipe 15 to the high-pressure injection nozzle 16. The sent raw material is injected from the high-pressure injection nozzle 16 at a high pressure of 30 to 250 MPa to form an injection stream, and this injection stream is quickly and simultaneously lowered to a low pressure state to perform a process of refining the fibers in the raw material. The high-pressure injection nozzle 16 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 performed multiple times on the fibers in the raw material. That is, the treatment liquid obtained in the chamber 8 may be sent to the raw material tank 2 using the treatment liquid return pipe 17, and then the micronization treatment may be performed again in the chamber 8. When the micronization treatment is performed multiple times, the treatment liquid is sent to the product tank 19 using the treatment liquid recovery pipe 18 and recovered as soon as the micronization treatment is completed. The product tank 19 may not be provided, and the raw material tank 2 and the product tank 19 may be shared. Also, the product tank 19 may be used as the raw material tank for the next micronization treatment to perform the second micronization treatment in the series.

[0031] If multiple high-pressure injection nozzles are connected to the chamber 8 and the injection flows collide at an angle of collision θ, the pulverization is more likely to proceed, and if 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, if 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, and the polymerization degree often decreases by more than 10% even after one round of pulverization. On the other hand, if it is greater than 178°, for example if the collision is 180°, i.e. if they collide head-on, the atomization effect will be increased, but there is a possibility that the opposing nozzle and surrounding equipment will be damaged. In the case of three nozzles, setting the angle θ to 120° will maximize the collision efficiency while minimizing damage to the nozzle and surrounding equipment. In addition, a pocket or the like may be provided in chamber 8 to receive the nozzle jets that are unable to collide with each other in the direction of travel of the nozzle jets and still retain momentum, thereby preventing damage to equipment.

[0032] In addition, when the micronization treatment is carried out multiple times, the number of times of treatment can be arbitrarily adjusted between 1 and 200 times. The properties of the resulting treatment liquid become smoother and more uniform as the treatment is repeated, and the fibers in the liquid become thinner and shorter. Therefore, it is possible to carry out the micronization treatment repeatedly the number of times according to the application. The fiber is subjected to the micronization treatment so that the average particle length of the fibers after pulverization is 1 / 4 or less, preferably 1 / 5 to 1 / 1000, more preferably 1 / 6 to 1 / 500, and even more preferably 1 / 7 to 1 / 100 of the average particle length of the polysaccharide before pulverization. Furthermore, to obtain fibers with an average particle length of 100 μm or less, a small number of repetitions is preferable, to obtain fibers with an average particle length of 20 μm or less, it is preferable to increase the number of repetitions to 5 or more, and to obtain fibers with an average particle length of 10 μm or less, it is preferable to have at least 10 repetitions.

[0033] 2, the intensifier 6 has an oil chamber 20 and a treatment liquid chamber 22. In the oil chamber 20, there is a rod 21b connected to an actuating member 21a. In addition, in the oil chamber 20, a pair of oil inlets and outlets 20a, 20b are provided with the actuating member 21a disposed in the center. In addition, the intensifier 6 is provided with connection ports 23 for suctioning and discharging raw material, respectively, which are connected to the intensifier supply pipe 7. When hydraulic pressure is applied to the inside of the oil chamber 20 through the oil inlet / outlet 20b and, at the same time, oil is discharged from the oil inlet / outlet 20a, the operating member 21a slides (from right to left in the figure), and the raw material is sucked into the treatment liquid chamber 22 through the liquid supply side check valve 11, the booster supply piping 7, the shared piping 33 and the connection port 23. On the other hand, when hydraulic pressure is applied to the oil chamber 20 through the oil inlet / outlet 20a and oil is simultaneously discharged from the oil inlet / outlet 20b, the operating member 21a slides (from left to right in the figure), and the raw material in a high-pressure state is discharged from the treatment liquid chamber 22 through the connection port 23, the common pipe 33, the booster supply pipe 7 and the high-pressure side check valve 14.

[0034] As a result of the pressure intensifiers 6 operating as described above, the device for micronizing a fiber-containing mixed liquid of this embodiment repeatedly sucks in and discharges the raw material in each pressure intensifier 6, and the raw material in a high-pressure state is supplied to the chamber 8 continuously and with little pulsation. In the embodiment described above, the actuation member 21a is driven by hydraulic pressure, but other power sources such as electricity may be used. These may also be used in combination. Using a servo device for position control allows smoother operation. In addition, while Fig. 1 shows a fiber finer device using three intensifiers, a single intensifier may be used, or four or more intensifiers may be used, each operated with a delay time of one cycle equal to the number of intensifiers, to more efficiently suppress pulsation. An odd number is preferable, and three is preferable in terms of the simplest control and cost reduction. In addition, an intensifier having a raw material suction port and a raw material discharge port at both ends and having an operating member 21a in the center may be used.

[0035] FIG. 3 shows a basic conceptual diagram of the liquid supply side check valve 11, the high pressure side check valve 14 and the booster supply piping 7. Supply-side check valve 11 is mainly composed of ball 25, a housing member 26, a removable member 24, and a valve seat 34. The material of ball 25 should preferably be a steel ball or the like with a high specific gravity (specific gravity in the range of 3 to 9, and more preferably 7 to 9), as this will ensure stable operation. Since dimension C, which is half the difference between the inner diameter A of containing member 26 inside the check valve and the outer diameter B of ball 25, is the space through which the mixed liquid flows, the larger dimension C is, the easier the mixed liquid will flow, and the smaller it is, the harder it will flow. The size of the ball should be selected so that the ratio of dimension C to inner diameter A is 10% to 50%, and 15% to 40% is even better. The accommodation member 26 is used to accommodate the removable member 24 and the ball 25, and the removable member 24 is used to accommodate the ball 25. The raw material supply pipe 10 and the accommodation member 26 are connected using a connection member 27. Here, the connection member 27 has a function of connecting them, as well as a function as a valve seat for the ball 25. The removable member 24 is provided with a liquid passage hole for passing the raw material. This can improve the durability of the liquid supply side check valve 11 itself. The size and shape of the liquid passage hole are not particularly limited, but it is better to make the liquid passage hole larger in order to pass the liquid smoothly and prevent the fibers from getting tangled. The inside of the removable member 24 may be provided with a mechanism such as a groove for guiding the ball 25 when passing the raw material. This can allow the ball 25 to operate stably and smoothly without being loose. The housing member 26 and the connection member 27 are formed of a metal such as stainless steel that is resistant to pressure and ultra-high pressure. The detachable member 24 receives substantially the same pressure from the outside and inside even in a high-pressure environment, so that it is not subjected to tension, twisting, bending, distortion, etc., and can maintain the movement of the ball. In addition, any material or thickness is acceptable as long as it can withstand compressive force, and plastic is not limited to metal, and can be used. The valve seat 34 is used as an auxiliary to reliably press the ball 25 against the connecting member 27 having a valve seat function to seal the raw material (see FIG. 4(c)). The valve seat 34 is an elastic member with a liquid passage hole in the center. If the ball 25 and the connecting member 27 were not used and sealing was performed by the line contact pressure on the circumference, the sealing performance would be significantly reduced if the line contact point was damaged, such as scratched, or if foreign matter was mixed in. In addition, there is a possibility that the valve seat 34 will not quickly settle into the sealing position. The material of the valve seat 34 is preferably elastic, and resin is preferable, and it is even more preferable that the material has excellent impact resistance. The use of the valve seat 34 stabilizes the operation, increases the transfer volume efficiency of the mixed liquid, increases the processing volume per stroke, and improves production efficiency.

[0036] The high pressure side check valve 14 is mainly composed of a ball 29, a housing member 30, and a valve seat 35. The ball 29 may be a steel ball having a heavy specific gravity similar to the ball 25. The storage member 30 is used to store the ball 29. The chamber supply high pressure pipe 15 and the storage member 30 are connected using a connection member 31. Although not shown, the storage member 30 and the connection member 31 are provided with a liquid passage hole through which the raw material flows when in the state of FIG. 4(c) described later. The size, shape, etc. of the liquid passage hole are not particularly limited. In addition, the inside of the storage member 30 may be provided with a groove or the like for guiding the ball 29 when passing the raw material. In this way, it is possible to prevent the ball 29 from being loose. Furthermore, although not shown, a member based on the same technical idea as the detachable member 24 may be provided. The storage member 30 and the connection member 31 are formed of a metal having pressure resistance to ultra-high pressure resistance such as stainless steel. Like valve seat 34, valve seat 35 is used auxiliary to reliably press ball 29 against connecting member 28 to seal in the raw material (see FIG. 4(b)). Also, its structure and material are similar to those of valve seat 34. Note that connecting member 28 also functions as a valve seat for ball 29, like connecting member 27.

[0037] The booster supply piping 7 is connected to the high pressure side check valve 14 using a connecting member 28, to the liquid feed side check valve 11 using a connecting member 32, and to the booster 6 using a branch piping 33. In this case, the shape of the booster supply piping 7 itself is not particularly limited, but it is preferable that the connecting member 28 has a shape corresponding to the liquid feed side check valve 11 and the high pressure side check valve 14 being installed approximately perpendicular to the floor surface. In another embodiment, as long as it is possible to connect so as to allow the raw material to pass and to enable stable production of the fiber refinement device, other methods and means may be used for connection, such as forming the members other than the detachable member 24, the balls 25, 29, and the valve seats 34, 35 into an integrated structure by machining. In this case, openings are provided that allow the liquid to pass when the balls 25, 29 are located on the upper side away from the connecting members 27, 28. Furthermore, the upper parts of the connecting members 27, 28 are provided with valve seats 34, 35 to ensure sealing when the balls are located on the lower side.

[0038] Fig. 4 shows (a) a state where the fiber refining device is stopped, (b) a state where the intensifier 6 is sucking in the raw material, and (c) a state where the intensifier 6 is discharging the raw material. The solid arrows in the figure indicate the flow of the raw material. The dashed arrows in the figure indicate that the raw material does not flow in the direction of the arrow. State (a) shows that ball 25 and ball 29 are both in the lower position. In addition, in state (b), a downward force of (1)+(2)+(3) is applied to ball 29 due to (1) the pressure toward ball 25 caused by the high-pressure raw material in the chamber supply high-pressure pipe, (2) the suction force of pressure intensifier 6, and (3) its own weight. On the other hand, an upward force of (1)+(2)-(3) is applied to the ball 25 due to (1) the suction force of the pressure intensifier 6, (2) the discharge pressure of the raw material circulating pump 3, and (3) its own weight.

[0039] In state (c), ball 29 is subjected to (1) an upward force due to the pressurization of pressure intensifier 6, (2) a downward force due to the internal pressure of the high-pressure pipe supplying to the chamber, and (3) upward forces (1)-(2)-(3) due to its own weight. On the other hand, a downward force of (1) - (2) + (3) is applied to ball 25 due to (1) the downward pressure from booster 6, (2) the upward force from the discharge pressure of pump 3, and (3) its own weight.

[0040] As described above, by using heavy steel balls for balls 25, 29 and by installing feed side check valve 11 and high pressure side check valve 14 approximately perpendicular to the floor surface, balls 25, 29 are installed so as to move approximately perpendicular to the floor surface. This allows each ball to fall under its own weight, making it possible to pass the raw material in only one direction. The supply side check valve and high pressure side check valve of the present invention are also advantageous in that they contribute to stable fiber refinement processing because the fibers in the dispersion do not get tangled in the spiral iron wire of a spring, which occurs in check valves that use elastic bodies such as springs in the past, and in that they prevent the outflow of ties of fibers into the high pressure spray nozzle, thereby eliminating clogging. Therefore, the supply side check valve and high pressure side check valve of the present invention can also be called check valves that do not use a spring, check valves that do not use a ball-retaining elastic body, or valves that utilize gravity and changes in flow pressure.

[0041] The fiber finer device according to the present invention having the above-mentioned configuration has the following advantages: In the following, a specific example will be described in which pulp is used as the raw material. The pulp mixture liquid is circulated between the raw material tank 2 and the raw material circulation path 4, so that the pulp can be made to flow in the raw material circulation path. By making it in this state, it is possible to prevent the pulp mixture liquid from staying and settling in the path, which would cause the pulp concentration to increase partially, and to eliminate malfunctions at the beginning of production and during production.

[0042] Furthermore, when the treatment liquid discharged from chamber 8 is returned to the raw material tank 2 to perform multiple refining processes, it is possible to return the mixed liquid to the raw material tank 2. Therefore, even if the viscosity gradually increases as the pulp is refined during the pulp refining process, by circulating the raw material at a constant flow rate or higher, the thixotropic properties of the raw material itself can be used to maintain the liquid in a flowing state with low viscosity, making it possible to stably carry out the fiber refining process. EXAMPLES

[0043] The present invention will be described below based on examples, but the present invention is not limited to these examples.

[0044] (Fiber length measurement) Using a fiber length measuring device (FS5 manufactured by Valmet), the fiber length of each fiber of hardwood pulp, softwood pulp, bamboo pulp, and ground cotton was measured according to JIS P 8226-2:2011. Note that the longer the fiber length and the larger the aspect ratio of the fiber, the more likely it is to become entangled in the spring inside the check valve. The measurement results are shown in Table 1.

[0045] [Table 1]

[0046] (Settling height test) The concentration of hardwood pulp, softwood pulp, bamboo pulp, ground cotton and chitin powder was adjusted to 1wt%, and a pulp settling height test was carried out using a 50ml centrifuge tube. The ratio of the settling height Hx at the time of measurement to the liquid surface height H0 of the mixed liquid containing fiber at each start time after 0 to 15 minutes (Hx / H0×100) is shown. Here, this settling height test is for evaluating the state inside the pipes of the micro-fining treatment device when the raw material is retained inside the pipes. A larger initial rate of change indicates that the fiber separates from the water and settles in a shorter time. A smaller value after 24 hours indicates that the volume occupied by the fibers holding water is smaller and the fiber bundle is more likely to become tighter. A larger value after 24 hours indicates that the fibers are more likely to spread out in a network-like manner in water and become entangled in the spring. The measurement results are shown in Table 2, and a graph showing time progression is shown in Figure 7. Cotton and chitin are considered to be materials that tend to settle in the pipes because they drain quickly in the initial stage (after 1 minute). In addition, coniferous trees and bamboo have a high chance of settling to a high depth after 24 hours, and are therefore considered to be materials that are likely to cause problems due to entanglement with the spring. On the other hand, based on the difference in settling height after 15 minutes and 24 hours (88.5-74.0=14.5%), it can be said that hardwood pulp has the property of settling slowly and gently, and is therefore considered to be a raw material with a high possibility of being able to undergo stable defibration processing.

[0047] [Table 2]

[0048] (Freeness measurement) According to JIS P 8121-2:2012, aqueous mixtures of hardwood pulp, softwood pulp, bamboo pulp, ground cotton, and chitin powder were prepared and freeness measurements were performed. The freeness measurements were performed to evaluate the ease of drainage when shear was applied. The higher the freeness measurement value, the faster the drainage, and it is thought that fibers that instantly lost water would clog the pipes. The measurement results are shown in Table 3. Ground cotton is a fiber that has a drying history, and has a high freeness value and is not compatible with water, so it drains quickly, and it is difficult to stably treat it with conventional equipment that does not have a circulation system. On the other hand, chitin powder has a lower freeness than hardwood pulp and is compatible with water.

[0049] [Table 3]

[0050] Example 1 Using the fiber-containing mixed solution refining treatment device of the present invention shown in Figure 1, refining treatment was carried out four times using softwood pulp with a solid concentration of 1% as the raw material at a pressure of 200 MPa and a high-pressure jet nozzle with an inner diameter of 0.5 mm. Here, a repetition is referred to as a pass, and four repetitions are referred to as 4 passes. After each refining treatment, a portion of the treatment solution was sampled and diluted with pure water to adjust the solid concentration to 0.1%, and the transmittance at 800 nm was measured. The measurement results are shown in Table 4.

[0051] Example 2 Except for using bamboo pulp with a solid concentration of 1% as the raw material, the refining treatment was carried out in the same manner as in Example 1. The measurement results are shown in Table 4.

[0052] Example 3 Except for using ground cotton with a solid concentration of 1% as the raw material, the micronization treatment was carried out in the same manner as in Example 1. The measurement results are shown in Table 4. Moreover, electron microscope photographs of the ground cotton and after 4 passes are shown in FIG.

[0053] Example 4 The micronization process was carried out in the same manner as in Example 1, except that chitin powder with a solid concentration of 1% was used as the raw material, and it was confirmed that the micronization process could be carried out without any problems.

[0054] [Table 4]

[0055] Table 4 shows that for all raw materials, the transmittance decreased as the number of passes increased, indicating that fibers refined by high pressure treatment were present in the supernatant and that this increased as the number of passes increased. Figure 5 also shows that cotton was refined to a fiber width of 25 nm or less, and that some of the fibers were refined to a fiber width of 15 nm or less.

[0056] Comparative Example 1 A conventional refining treatment device 36 shown in FIG. 6 was used, which has a check valve 39 using a spring on each of the suction and discharge sides of the booster and no path for circulating the raw material, to perform refining treatment using softwood pulp with a solid concentration of 1% as the raw material.

[0057] Comparative Example 2 The micronization treatment was carried out in the same manner as in Comparative Example 1, except that ground cotton with a solid concentration of 1% was used as the raw material.

[0058] (result) In Comparative Example 1, the micronization device stopped during the first treatment shortly after it started, and when the piping was removed and the inside was inspected, the fibers were entangled in the spring. The second micronization treatment could not be performed. In Comparative Example 2, the treatment liquid was no longer discharged immediately after it started. When the piping was removed and the inside was inspected, the fibers were entangled in the spring, and the surrounding piping was filled with fibers and the cotton was infarcted in the piping. The micronization treatment could not be continued. [Explanation of symbols]

[0059] 1... Fiber-containing mixed liquid micronization device, 2... Raw material tank, 3... Raw material circulation pump, 4... Raw material circulation path, 5... Chamber supply high pressure path, 6... Booster, 7... Booster supply piping, 8... Chamber, 9... Raw material withdrawal piping, 10... Raw material supply piping, 11... Liquid supply side check valve, 12... Raw material return piping, 13a, 13b... Branching section, 14... High pressure side check valve, 15... Chamber supply high pressure piping, 16... High pressure spray nozzle, 17... Processed liquid return piping, 18... Processed liquid recovery piping, 19... Product tank, 20... Oil chamber, 20a, 20b... oil inlet / outlet, 21a... operating member, 21b... rod, 22... treatment liquid chamber, 23... connection port, 24... detachable member, 25... ball, 26... accommodation member, 27... connection member, 28... connection member, 29... ball, 30... accommodation member, 31... connection member, 32... connection member, 33... branch pipe, 34... low pressure side valve seat, 35... high pressure side valve seat, 36... conventional refinement treatment device, 37... pressure booster, 38... refinement treatment means, 39... check valve using a spring, 40... heat exchanger, 41... raw material tank

Claims

1. At least a raw material tank, a raw material circulation pump, A booster and a raw material circulation path including a raw material supply pipe, a feed side check valve, and a raw material return pipe; a chamber supply high pressure path including a chamber supply high pressure pipe and a high pressure side check valve; A chamber equipped with a micro-processing means. A fiber-containing mixed liquid microparticulation treatment device, The raw material return pipe is for returning the raw material to the raw material tank.

2. The liquid supply side check valve is installed so as to be approximately perpendicular to the floor surface. A device for treating a mixed liquid containing the fiber according to claim 1 to refine the fiber.

3. The supply side check valve includes a removable member. A device for treating a mixed liquid containing the fiber according to claim 1 to refine the fiber.

4. The liquid supply side check valve is a check valve that does not use a spring. A device for treating a mixed liquid containing the fiber according to claim 1 to refine the fiber.

5. The ball used in the liquid supply side check valve is made of a material having a specific gravity of 3 to 9. A device for treating a mixed liquid containing the fiber according to any one of claims 1 to 4.

6. The high pressure side check valve is a check valve that does not use a spring. A device for treating a mixed liquid containing the fiber according to claim 1 to refine the fiber.

7. The ball used in the high pressure side check valve is made of steel. A device for treating a mixed liquid containing the fiber according to claim 5 to refine the fiber.

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