JP2006176558A - Method for preparing finely ground rubber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To further and efficiently reduce the particle diameter of a finely ground rubber. <P>SOLUTION: The method for preparing the finely ground rubber comprises the crushing step of crushing rubber chips into a coarsely crushed rubber by means of a crusher, the grinding step of grinding the coarsely crushed rubber into a finely ground rubber by means of a fine grinder, the separation step of forcibly separating particles each composed of joined finely ground rubber particles and contained in the finely ground rubber into individual finely ground particles by applying thereto an impact by means of a separator; the mixing step of mixing the finely ground rubber by means of a mixer while adding an antistick agent thereto; and the classification and recovery step of classifying (sorting) the antistick-agent-containing ground rubber into a finely ground rubber product of a specified particle diameter and the rest and recovering them. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for producing finely pulverized rubber for pulverizing used rubber such as waste tires.

For example, powder processing is performed to recycle rubber materials separated from waste tires (old tires), various industrial rubber products that have been discarded, and the like. The rubber pieces produced by crushing and crushing waste tires in the form of granules and powders are collectively referred to as "rubber powder", and this rubber powder generally has a particle size of about 0.3 to 5 mm. Are used as material recycling.
As conventional rubber powder processing methods, those described in JP-B-61-9973, JP-A-10-80901, JP-A-2001-315121, and JP-A-6-179215 (hereinafter referred to as “conventional”). Example 1 ”,“ Conventional Example 2 ”,“ Conventional Example 3 ”and“ Conventional Example 4 ”) have been proposed, and their production methods are as follows.
Conventional Example 1 relates to a method for producing a rubber powder having a particle size of 200 to 1500 μm (0.2 to 1.5 mm) and a powdering agent content of less than 7% by weight. In this manufacturing method, rubber is converted into particles having pores on the surface by a particle size reduction machine, and a powdering agent (a derivative of silica, calcium carbonate, etc.) is sprayed into the supply flow of rubber particles by air pressure to flow the rubber. The rubber particles are crushed at a low temperature so that the surface of the rubber powder formed by pulverization is not damaged, and the rubber powder is pulverized at a low temperature, and after the re-pulverizing agent treatment, the rubber powder is heated to such an extent that no rubber flow occurs. It is cooled by a cooling device.
Conventional Example 2 is a powder rubber having a large number of hollow portions on the surface, a particle size of 200 to 700 μm (0.2 to 0.7 mm), and a bulk specific gravity of less than 0.15 to 0.3 g / cm ³ . It relates to a manufacturing method. In this production method, a lump of rubber as a raw material is put into a kneader and kneading is started. When the temperature of the rubber rises to some extent, a vulcanizing agent and a vulcanization accelerator are added and kneading is continued. It is converted into a body, pulverization starts from the middle of kneading, and hollow powder rubber is obtained.
In the conventional example 3, as described in paragraph 0037 to paragraph 0039 of the sixth page of the gazette, first, an old tire is roughly crushed using a well-known cracker roll while having a certain particle size. In the crushing step, a mesh of 3 mesh or less is used. Next, the coarsely crushed material is pulverized by a pulverizing roll while providing a predetermined mesh to make the particle diameter uniform. Finely pulverize so that the particle size of the pulverized product after grinding is about 5.0 × 10 ⁻⁴ (m). Thereafter, talc as a caking suppressant is blended into the finely pulverized product using a tumbler mixer. Then, the obtained rubber powder is inspected to confirm whether or not it has been obtained in a predetermined manner. Even when the obtained powdered rubber has a fine particle size, the powdered rubber does not solidify with each other, has sufficient fluidity and good handling properties.
Conventional Example 4 relates to a method for pulverizing a vulcanized rubber material. In Example 1, as described in the publication, page 3, paragraph 0014 to page 5, paragraph 0026, the tire waste material is first roughly pulverized to a particle size of about 20 mm using a pulverizer, and then obtained. The obtained coarse powder was put into a hopper of a twin screw extruder having a screw diameter D of 30 mm and a ratio L / D of the screw diameter D to the screw length L of 24. The following temperature is set in each of the divided areas 1 to 4 and fed into the cylinder, and a shearing force is applied in the extruder to give a fine particle size of 10 to 70 μm (0.01 to 0.07 mm). A powder is obtained.
Region 1: 130 ° C
Region 2: 150 ° C
Region 3: 170 ° C
Region 4: 170 ° C
Japanese Patent Publication No.61-9973 Japanese Patent Laid-Open No. 10-80901 JP 2001-315121 A JP-A-6-179215

The rubber powder obtained by the method for producing powder rubber has a particle diameter of 200 to 1500 μm (0.2 to 1.5 mm) in Conventional Example 1, and a particle diameter of 200 to 700 μm (0.2 to 0.7 mm) in Conventional Example 2. In the conventional example 3, the particle size is about 5.0 × 10 ⁻⁴ (m), and although it is used as rubber powder, it can be used as a raw material for tires in the same manner as ordinary rubber. In order to expand, it is required that the particle size is smaller, and each conventional example has room for improvement. Moreover, in the prior art example 4, since the rubber powder obtained is a fine powder having an average particle size of 10 to 70 μm (0.01 to 0.07 mm), the above requirement is satisfied, but the cylinder of the extruder is divided into four parts. In each region, it is necessary to set a heating temperature of 240 ° C. or lower, temperature management is not easy, and there is a problem in that work efficiency is reduced.
An object of the present invention is to provide a method for producing a finely pulverized rubber capable of further reducing the particle diameter more efficiently.

The first feature of the present invention is a coarse pulverization step in which a crushed rubber raw material is processed into coarse pulverized rubber by means of coarse pulverization means, a fine pulverization step in which the coarse pulverized rubber is processed into fine pulverized rubber by a fine pulverization roll, And a separation step of forcibly separating the rubber particles contained in the finely pulverized rubber and continuous with each other by applying an impact force by a separator to a finely pulverized rubber.
The second feature of the present invention is that, based on the first feature, the crushed rubber raw material is a rubber chip, the rubber chip particle diameter D is 1 mm to 8 mm, and the coarse pulverization means includes a fixed blade, a coarse pulverization roll, The pitch of the pulverizing blades of the coarse pulverization roll is 1.0 mm to 1.5 mm, the angle formed by the adjacent pulverization blades is 85 ° to 95 °, and the fixed blade and the coarse pulverization roll facing each other Is that the gap is D / 30 to 35.
According to a third feature of the present invention, on the premise of the first feature, the crushed rubber raw material is a rubber chip, and the rubber chip particle diameter D is 1 mm to 8 mm. The coarse pulverizing means includes a fixed blade, a coarse pulverization roll, The rotational speed of the pulverizing roll is 80 rpm or more, the pitch of the pulverizing blades of the coarse pulverizing roll is 1.0 mm to 1.5 mm, and the angle θ formed by the adjacent pulverizing blades is 85 ° to 95 °. The gap between the opposed fixed blade and the coarse pulverization roll is D / 30 to 35.
According to a fourth feature of the present invention, on the premise of the first feature, the crushed rubber raw material is a rubber chip, the rubber chip particle diameter D is 1 mm to 8 mm, and the coarse pulverizing means includes a fixed blade, a coarse pulverization roll, The rotational speed of the pulverizing roll is 80 rpm or more, the pitch P of the pulverizing blade of the coarse pulverizing roll is 1.0 mm to 1.5 mm, and the height of the pulverizing blade is P / 2.5-3. 5. The angle formed by the adjacent crushing blades is 85 ° to 95 °, and the gap between the opposed fixed blade and the coarse crushing roll is D / 30 to 35.
According to a fifth feature of the present invention, on the premise of any one of the first to fourth features, the fine grinding means has a plurality of stages with a pair of a low speed side grinding roll and a high speed side grinding roll that rotate in opposite directions. The surface of the pair of pulverizing rolls is a smooth surface, and the rotation ratio of the pulverizing rolls on the low speed side and the high speed side is 1: 15-30.
According to a sixth feature of the present invention, on the premise of any one of the first to fourth features, the fine pulverizing means has a plurality of stages, each paired with a low speed side pulverization roll and a high speed side pulverization roll that rotate in opposite directions. The surface of the pair of pulverizing rolls is a fine uneven surface, and the rotation ratio of the pulverizing rolls on the low speed side and the high speed side is 1: 15-30.
According to a seventh feature of the present invention, on the premise of any one of the first to fourth features, the fine pulverizing means has a plurality of stages with a pair of a low-speed side pulverizing roll and a high-speed side pulverizing roll rotating in opposite directions. The surface of the pair of pulverizing rolls is a fine concavo-convex surface, the rotation ratio of the pulverizing rolls on the low speed side and the high speed side is 1: 15-30, and the height of the protrusions on the concavo-convex surface is greater than 0 mm to 0. It is in being 05 mm or less.
The eighth feature of the present invention is that, based on any one of the first to seventh features, the filling rate of the finely pulverized rubber charged into the separation chamber of the separator is 30% to 40%. is there.
According to a ninth aspect of the present invention, on the premise of any one of the first to eighth aspects, a mixing step of mixing while adding an anti-sticking agent to the finely pulverized rubber that has undergone the separation step by a mixer is provided. There is.
According to a tenth feature of the present invention, on the premise of any one of the first to eighth features, a mixing step of mixing while adding an anti-sticking agent to a finely pulverized rubber that has undergone the separation step by a mixer, and this mixing There exists a classification collection process which classifies the finely pulverized rubber | gum in a process with a classifier, and collect | recovers it as a fine powder rubber product.

  According to the present invention, a rubber raw material is subjected to a coarse pulverization process and a fine pulverization process, whereby finely pulverized rubber having pores on the surface and a very small particle size in a crimped form is obtained, and further pulverized by a separator. A finely pulverized rubber can be efficiently produced by applying an impact force to continuous rubber particles in the rubber and forcibly separating them.

The method for producing finely pulverized rubber according to the present invention shown in FIGS. 1 and 2 includes the following five steps.
Coarse pulverization step: The rubber chips are processed into coarse pulverized rubber by the coarse pulverizer 1.
Fine pulverization step: The coarse pulverized rubber is processed into fine pulverized rubber by the fine pulverizer 2.
Separation step: Separator for finely crushed rubber particles connected to each other.
The impact force is applied by 3 to forcibly separate into a finely crushed rubber.
Mixing step: Mixing is performed while adding an anti-sticking agent to the finely pulverized rubber by the mixer 4.
Classifying and collecting step: The finely pulverized rubber to which the anti-sticking agent has been added by the classifier 5 has a predetermined particle size.
Classify (select) and collect fine rubber product and other products.

In the coarse pulverization step, as shown in FIG. 2, for example, rubber chips (tire chips) obtained by crushing a cut tire obtained by cutting a waste tire (having a tire reinforcing material such as a beat wire removed) into a predetermined size are used as rubber raw materials. As shown in FIG. 3, the pulverizer is fed into the hopper 1a of the coarse pulverizer 1 from the supply tower 6 and processed into coarse pulverized rubber by the coarse pulverization means 7 (FIG. 3) provided in the pulverization chamber. The particle size of the rubber chip to be introduced is, for example, in the range of 1 mm to 8 mm.
The coarsely pulverized rubber is a rubber having pores on the surface, in a crimped form and having flexibility (hereinafter, referred to as “coarse crumb rubber”).
In order to make it possible to efficiently produce rough curled rubber, the coarse crushing means 7 shown in FIG. 3 has a combination of a fixed blade 7a and a crushing roll 7b arranged in a single stage or a plurality of stages (two stages in the figure) in the vertical direction of the figure. Configured.
In addition, what combined the fixed blade 7a and the grinding | pulverization roll 7b may be arranged in the horizontal direction, and may be arranged in multiple steps in the horizontal direction.
A gap W (FIG. 3) is provided between the opposed fixed blade 7a and the grinding roll 7b. When the particle diameter of the rubber chip to be introduced is D, the gap W is preferably D / 30 to 35.
In one fixed blade 7a, as shown in FIGS. 4 and 5, an arc surface 7a1 which is concave on the inner side (left side in FIG. 4) is formed on the side facing the crushing roll 7b. The outer peripheral surface of the pulverizing roll is fitted. A plurality of grooves 7a11 extending in the left-right direction in FIG. 5 are provided on the circular arc surface 7a1 of the fixed blade 7a at intervals in the vertical direction.
In the other grinding roll 7b, as shown in FIGS. 3 and 6, a grinding blade 7b1 is provided on the outer peripheral surface of the grinding roll. In FIG. 6, the direction of the pulverizing blade 7b1 is inclined from the central part of the pulverizing roll 7b on both the left and right sides and obliquely upward, and has a “V” shape centering on this central part. As shown in FIG. 7, the pitch P of the pulverizing blades 7b1 is preferably in the range of 1.0 mm to 1.5 mm. If the value of the pitch P is out of the above range, it is difficult to produce the expected rough crumb rubber. If it is less than about 1.0, it takes time for the coarse pulverization process. It adversely affects work efficiency at the process stage. The angle θ formed by the adjacent crushing blade 7b1 is preferably in the range of 85 ° to 95 °. When the angle θ is out of the above range, the expected production efficiency of the rough rubber is lowered. When the angle θ <85 °, the durability of the cutting edge is lowered. When the angle θ> 95 °, Coarse pulverization takes time. As for the rotation speed of the grinding | pulverization roll 7b, 80 rpm or more is desirable. If the rotational speed does not reach 80 rpm, there is a risk that the production efficiency of the expected rough drown rubber will be reduced. The height d of the crushing blade 7b1 is preferably a pitch P / 2.5 to 3.5.
During coarse pulverization, the pulverization work is performed while rotating the pulverization roll 7b with respect to the fixed blade 7a in a fixed state. Rubber can be manufactured, and the direction of the grinding blade 7b1 is “V” centered on the center of the grinding roll 7b, so that the coarsely crushed rubber is moved to the center of the grinding roll 7b and coarsely crushed. Work is done efficiently.
Coarse rubber that has been processed in the coarse pulverization process is small in that the combined action of compressive force and frictional force propagates through the particles in the rubber that is the object of coarse pulverization, generating smaller boundaries in the rubber particles. It is in a pulverized state while forming a lump.
In the coarse pulverization step, even if the rubber particles of the coarsely crushed rubber are combined and in an agglomerated state, one particle (rubber particle) can be pulverized to a particle size of 0.5 mm or less. Various conditions such as the rotational speed, P (pitch), θ (angle), d (height) of the grinding blade, and the gap W between the fixed blade 7a and the grinding roll 7b are adjusted.
Note that the direction of the crushing blade 7b1 does not necessarily need to form a “V” shape.
The coarse crushing means 7 may be a biaxial one that rotates a pair of rolls in the opposite direction and has different rotation speeds. In this case, it becomes possible to produce a coarse rubber of a certain size by the action of the shearing force and frictional force between the grinding blades of the pair of rolls.

In the fine pulverization step, the coarsely crushed rubber is processed into fine pulverized rubber by the fine pulverizer 2.
As shown in FIG. 2, the coarsely pulverized rubber processed by the coarse pulverizer 1 is conveyed to the fine pulverizer 2 by the screw conveyor 1b and the belt conveyor 8, and is put into the hopper 2a of the fine pulverizer, and into the pulverization chamber. The finely pulverized rubber is processed by the finely pulverizing means 9 (FIG. 8).
The finely crushed rubber is a rubber having a pore size on the surface as compared with the coarsely crushed rubber and having a smaller particle size and being in a crimped form (hereinafter referred to as “finely crushed rubber”).
The fine pulverizing means 9 is a combination of a pair of pulverizing rolls 9a and 9b arranged in a plurality of stages in the vertical direction (six stages in the figure) as shown in FIG. Configured.
A combination of a pair of crushing rolls 9a and 9b may be arranged in the horizontal direction and arranged in a plurality of stages in the horizontal direction.
The pulverizing roll 9a and the pulverizing roll 9b have different rotational speeds. The crushed rolls 9a and 9b further pulverize the coarsely squeezed rubber (by reducing the particle size of the coarsely squeezed rubber and narrowing the distribution of the diameters) so that the fine squeezed can be produced. The surface of the roll is preferably a smooth surface or a fine uneven surface. In the fine pulverization process for converting from coarsely crushed rubber to finely crushed rubber, the gap between the opposing pulverizing rolls 9a and 9b is set as narrow as possible, for example, 0.05 mm or less, while the pulverized rubber is guided between the pulverizing rolls. The compression force gradually increases and the compression force increases as it approaches the gap between the pulverization rolls, and the compression force and the frictional force are applied to the pulverized rubber due to different relative speed differences of the rotation ratio of the pulverization rolls. In the gap, a shearing force is finally applied, and the pulverization is realized.
The grinding efficiency of the finely crushed rubber greatly depends on the relative rotation ratio of the grinding rolls 9a and 9b. The rotation ratio between the low-speed side pulverizing roll 9a and the high-speed side pulverizing roll 9b is preferably in the range of 1:15 to 30 (1/30 to 1/15). If the rotation ratio is out of the above range, the production efficiency of the finely squeezed rubber may be lowered. When the rotation ratio is less than 1:30, that is, less than 1/30, the rotation of the high-speed side pulverizing roll 9b is considerably faster than that of the low-speed side pulverizing roll 9a. If it exceeds 1:15, that is, 1/15, the pulverization efficiency may be reduced.
Further, when the surface of each pulverizing roll on the low speed side and the high speed side is a fine concavo-convex surface (in FIG. 9, a rough surface in which protrusions 19a1 having a predetermined height h are densely arranged on the surface of the pulverizing roll 19a), In order to reduce the particle size of the twisted rubber, the height h of the protrusion 19a1 on the uneven surface is preferably set to be greater than 0 mm and not greater than 0.05 mm. By setting in this way, the finely crushed rubber is combined and in a condensed state, but it becomes possible to make one rubber particle size 0.15 mm or less. About 90% of the rubber was occupied by rubber particles having a particle size of 0.15 mm or less.
In the fine pulverization step, in order to finely pulverize the coarse rubber, as described above, the rotation ratio of the pulverizing rolls 9a and 9b, the surface of the pulverizing roll (smooth surface, fine uneven surface, projection height h) and Adjust each condition such as the number of grinding (single stage, multiple stages).
The finely crushed rubber obtained in the fine pulverization process forms a lump (condensed state) in which rubber particles are combined, but the particle size of one rubber particle (rubber particle) is small and the surface is fine. When used as a raw material, it has an uneven surface, has a large surface area, and has a large reaction surface with other raw materials, and as a result, the rubber strength is maintained.

In the separation step, impact force is applied to the finely pulverized rubber particles connected to each other by the separator 3 to forcibly separate the finely pulverized rubber particles into a finely pulverized rubber. .
As shown in FIG. 2, the finely crushed rubber processed by the fine pulverizer 2 is conveyed to the separator 3 by the screw conveyor 2b, is introduced into the inlet 3a of the separator, and is provided in the separation chamber. It is processed into finely crushed rubber by rotation of a rotating disk with a pin. The rotating disk with the pin is rotated by the driving force of the driving motor 3b, and the pin rotates and moves in the circumferential direction in the separation chamber along with the rotation, and the small rubber thrown into the moving pin repeatedly collides with the impact. The force and the frictional force between the squeezed rubbers on the airflow generated by the pin rotating at high speed contribute to the separation. The peripheral speed of the rotating disk with pins is preferably 50 m / s or more, but the range of this peripheral speed is appropriately set according to the size and volume ratio of the rotating disk with pins and the required particle size.
The amount of the finely crushed rubber into the separator 3 varies depending on the filling rate relative to the volume of the separation chamber. However, according to the experimental example, the filling rate ranges from 30% to 40% to obtain the maximum efficiency. Is preferred. This fact is considered to be efficiently separated not only by the collision force of the fine rubber but also the pin, but also by the collision and friction of the fine rubber.
In order to suppress a decrease in separation efficiency, the room temperature (treatment temperature region) of the separation chamber in the separator 3 is preferably 40 ° C to 160 ° C. If the temperature exceeds 160 ° C, the stickiness of the finely crushed rubber will increase and the separation effect will be reduced. If the temperature is lower than 40 ° C, the rubber will put a load on the separator as it hardens, reducing the production efficiency. There is a risk of inviting.

In the mixing step, an anti-sticking agent is added and mixed by the mixer 4 to the finely pulverized rubber that has undergone the separation step.
As shown in FIG. 2, the finely pulverized rubber processed by the separator 3 is pumped to the tank 4a of the mixer 4 by the transport duct 3c and supplied into the mixing chamber 4b provided at the lower part of the tank. . An anti-sticking agent supply tank 4c is connected to the mixing chamber 4b, and the anti-sticking agent is supplied from the supply tank 4c into the mixing chamber. The finely crushed rubber and the anti-sticking agent supplied into the mixing chamber 4b are stirred and mixed by the mixing means 4d including a stirring screw provided in the mixing chamber.
As the anti-sticking agent, fillers (calcium carbonate, alumina, etc.) and reinforcing materials (carbon black, talc, silica, etc.) are suitable.
When calcium carbonate is selected as the anti-sticking agent, the amount added is preferably 7% to 15% of the finely crushed rubber. If it is less than 7%, the anti-sticking function is lowered, and if it exceeds 15%, the field of use when it is commercialized is limited.
By adding an anti-sticking agent to the finely pulverized rubber, the surface of the finely pulverized rubber can be coated to prevent the finely pulverized rubber from adhering and bonding again, and a predetermined particle size is required depending on the use of the rubber. In this case, there is an advantage that the required particle size can be classified (selected) by a simple classifier. While securing this kind of advantage, a small addition amount of the anti-sticking agent contributes to cost reduction and is advantageous for reuse as a tire raw material. For this reason, the mixing speed by the mixing means 4d is a low speed range so that once coated, it does not peel from the surface of the finely pulverized rubber, and does not enter the fine holes on the surface and disable the sticking prevention function. It is preferable.

The classifying and collecting step is a step of classifying and collecting the finely pulverized rubber added with the anti-sticking agent in the mixing step with the classifier 5.
In the classifying and collecting step, the finely pulverized rubber added with the anti-sticking agent in the mixer 4 is stored in the primary storage tank 5a of the classifier 5 by the transport duct 4e, and is transferred from the primary storage tank 5a to the secondary storage tank 5b. Stored. The finely pulverized rubber stored in the secondary storage tank 5b gradually falls from the lower outlet to the sieve 5c, and by this sieve, finely pulverized rubber having a predetermined particle diameter, and other than that, that is, fine pulverized rubber exceeding the predetermined particle diameter. The finely crushed rubber having a predetermined particle diameter is collected in the collection tank 5d as a fine powder rubber product, and the fine pulverized rubber exceeding the predetermined particle diameter is collected as a fine powder rubber product separately from the collection tank 5d. It is recovered in the tank and returned to the fine pulverizer 2 as necessary to perform a process for obtaining finely pulverized rubber having a predetermined particle size.
The finely pulverized rubber having a predetermined particle size is, for example, one having a particle size of 0.15 mm (# 100) or less, and other finely pulverized rubbers having a particle size exceeding 0.15 mm (# 100).

A first embodiment will be described.
Using a coarse pulverizer 1 having a fixed blade and a pulverizing roll in which 3 mm rubber chips are arranged in two stages, the clearance W between the fixed blade 7a and the pulverizing roll 7b is 3/31, the rotational speed of the pulverizing roll is 82 rms, P = It was set to 1.20 and processed into a rough crushed rubber by the grinding chamber.
Using a fine pulverizer 2 equipped with six low speed side pulverizing rolls 9a and high speed side pulverizing rolls 9b, the rotation ratio of the high and low side pulverizing rolls is set to 1:15, and the coarsely squeezed rubber is fined. Processed slightly.
A finely crushed rubber was obtained by performing separation processing at a peripheral speed of a rotating disk with a pin of 60 m / s, setting the filling rate of finely crushed rubber into the separation chamber of the separator to 35%. Of the finely pulverized rubber, those having a particle size of 0.15 mm (# 100) or less were about 90%, and the remainder were those exceeding 0.15 mm.
In the mixing chamber of the mixer 4, 8% calcium carbonate as an anti-sticking agent was added to the finely crushed rubber and mixed, and then classified. The finely pulverized rubber having a particle size of 0.15 mm (# 100) or less was recovered as a product, and the finely pulverized rubber exceeding the particle size was returned to the fine pulverizer 2.

In the method for producing finely pulverized rubber of the present invention described above, in the coarse pulverization step, pores are formed on the surface of the rubber chip so that the coarse pulverization means 7 pulverizes by shearing while applying frictional force or compression force to the surface of the rubber chip. In addition, in the fine pulverization step, the surface of the coarsely crushed rubber is pulverized while applying a frictional force or a compressive force by the fine pulverization means 9, so that the pulverization step is further compared with the coarse pulverization step. Concavities and convexities are formed on the surface and processed into a finely crushed rubber, and in the separation step, an impact force is applied to the finely crushed rubber, so that the particles in the bound state are forcibly separated and a particle size of 0. Finely pulverized rubber smaller than 15 mm (# 100) can be mass-produced.
By adjusting the processing conditions of the coarse pulverization means 7 and fine pulverization means 9, fine powder rubber having a fine pulverization region of 0.15 mm (# 100) to 0.075 mm (# 200) or a particle size within the range is machined. It can be mass-produced by mechanical grinding.
In the separation process, the finely crushed rubber is forcibly dispersed into the finely crushed rubber that is in an agglomerated state where the rubber particles are continuous, but the separated finely crushed rubber is classified and collected without going through the mixing process. The process may be shifted to a fine powder rubber having a predetermined particle size and other types by using a classifier using wind power, for example, and a mixing process for adding an anti-sticking agent is not necessarily required.

It is a flowchart of the manufacturing method of the pulverized rubber | gum which concerns on this invention. It is a block diagram which shows the manufacturing system for enforcing the manufacturing method of the fine ground rubber | gum which concerns on this invention. It is an enlarged front view of the crushing means used at the coarse grinding | pulverization process of the manufacturing method of the fine grinding rubber | gum which concerns on this invention. It is an enlarged front view of the fixed blade of the crushing means used in the rough crushing step of the method for producing finely pulverized rubber according to the present invention. It is an enlarged side view of the fixed blade of the crushing means used in the rough crushing step of the method for producing finely pulverized rubber according to the present invention. It is an enlarged front view which shows the principal part of the grinding | pulverization roll used at the coarse grinding | pulverization process of the manufacturing method of the fine grinding rubber | gum which concerns on this invention. It is an expanded block diagram which shows a part of blade of the grinding | pulverization roll used at the coarse grinding | pulverization process of the manufacturing method of the fine grinding rubber | gum which concerns on this invention. It is an enlarged front view which shows the grinding | pulverization roll of the fine grinding | pulverization means used at the fine grinding | pulverization process of the manufacturing method of the fine grinding rubber | gum which concerns on this invention. It is an enlarged front view which shows a part of outer peripheral part of the grinding | pulverization roll of the other example in the fine grinding | pulverization means used at the fine grinding process of the manufacturing method of the fine grinding rubber | gum which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Coarse pulverizer 2 Fine pulverizer 3 Separator 4 Mixer 5 Classifier 7 Coarse pulverizer 7a Fixed blade 7a1 Arc surface 7a11 Groove 7b Crush roll 7b1 Crush blade 9 Fine pulverizer 9a, 9b Crush roll 19a Crush roll 19a1 Projection P Pitch of coarse pulverizing roll pulverizing blade W Clearance between opposed fixed blade and coarse pulverizing roll d Height of coarse pulverizing roll pulverizing blade h Height of protrusion θ Angle formed by adjacent pulverizing blade

Claims (10)

A coarse pulverization step of processing the crushed rubber raw material into coarse pulverized rubber by means of coarse pulverization;
A fine pulverization step of processing the coarsely pulverized rubber into fine pulverized rubber by a fine pulverization roll;
Separating the rubber particles contained in the finely pulverized rubber and connected to each other by applying an impact force with a separator to forcibly separate them into a finely pulverized rubber. A method for producing finely crushed rubber.   The crushed rubber raw material is a rubber chip, the rubber chip particle diameter D is 1 mm to 8 mm, the coarse pulverizing means has a fixed blade and a coarse pulverization roll, and the pitch of the pulverization blade of the coarse pulverization roll is 1.0 mm to The angle between adjacent grinding blades is 85 ° to 95 °, and the gap between the opposed stationary blade and the coarse grinding roll is D / 30 to 35. A process for producing the finely pulverized rubber described.   The crushed rubber raw material is a rubber chip, and the rubber chip particle diameter D is 1 mm to 8 mm. The coarse pulverizing means has a fixed blade and a coarse pulverization roll, and the rotational speed of the pulverization roll is 80 rpm or more. The pitch between the pulverizing blades is 1.0 mm to 1.5 mm, the angle θ formed by the adjacent pulverizing blades is 85 ° to 95 °, and the gap between the opposed fixed blade and the coarse pulverizing roll is D / 30 to The method for producing a finely pulverized rubber according to claim 1, wherein   The crushed rubber raw material is a rubber chip, and the rubber chip particle diameter D is 1 mm to 8 mm. The coarse pulverizing means has a fixed blade and a coarse pulverization roll. The pitch P of the crushing blades is 1.0 mm to 1.5 mm, the height of the crushing blades is P / 2.5 to 3.5, and the angle formed by the adjacent crushing blades is 85 ° to 95 °, 2. The method for producing finely pulverized rubber according to claim 1, wherein a gap between the opposed fixed blade and the coarsely pulverized roll is D / 30 to 35.   The fine pulverizing means has a plurality of stages of a pair of a low speed side pulverizing roll and a high speed side pulverizing roll that rotate in directions opposite to each other, the surfaces of the pair of pulverizing rolls are smooth surfaces, and the low speed side and high speed side pulverizing rolls The method for producing a finely pulverized rubber according to any one of claims 1 to 4, wherein the rotation ratio is 1:15 to 30.   The fine pulverizing means has a plurality of stages with a pair of a low-speed side pulverizing roll and a high-speed side pulverizing roll that rotate in directions opposite to each other, and the surface of the pair of pulverizing rolls is a fine uneven surface, and the low-speed side and high-speed side pulverization The method for producing a finely pulverized rubber according to any one of claims 1 to 4, wherein a rotation ratio of the roll is 1:15 to 30.   The fine pulverizing means has a plurality of pairs of low-speed side pulverization rolls and high-speed side pulverization rolls rotating in opposite directions, and the surface of the pair of pulverization rolls is a fine uneven surface, and the low-speed side and high-speed side pulverization rolls The pulverization ratio according to any one of claims 1 to 4, wherein the rotation ratio is 1:15 to 30 and the height of the protrusions on the concavo-convex surface is greater than 0 mm and less than or equal to 0.05 mm. How to make rubber.   The method for producing a finely pulverized rubber according to any one of claims 1 to 7, wherein a filling rate of the finely pulverized rubber introduced into a separation chamber in the separator is 30% to 40%.   The method for producing a finely pulverized rubber according to any one of claims 1 to 8, further comprising a mixing step of mixing the finely pulverized rubber having undergone the separation step while adding an anti-sticking agent by a mixer.   It has a mixing step of mixing while adding an anti-sticking agent to the finely pulverized rubber that has passed through the separation step, and a classifying and recovering step of classifying the finely pulverized rubber in this mixing step with a classifier and recovering it as a finely powdered rubber product. The method for producing a finely pulverized rubber according to any one of claims 1 to 8, wherein:

Images