阅读说明：本技术 团粒的制造方法和块状体的制造方法 (Method for producing pellet and method for producing block ) 是由 中村昌生 于 2019-02-04 设计创作，主要内容包括：本发明的一个方式是在团粒的制造方法中包含下述工序：在沿规定方向流动的温水中供给橡胶溶液和过热蒸汽、使上述橡胶溶液与上述过热蒸汽接触。(One embodiment of the present invention is a method for producing pellets, comprising the steps of: a rubber solution and superheated steam are supplied to warm water flowing in a predetermined direction, and the rubber solution is brought into contact with the superheated steam.)

1. A method for producing pellets, comprising the steps of: a rubber solution and superheated steam are supplied to warm water flowing in a predetermined direction, and the rubber solution is brought into contact with the superheated steam.

2. The method for manufacturing a granule according to claim 1, wherein the warm water contains a dispersant.

3. The manufacturing method of pellets according to claim 1 or 2, wherein the warm water flows in a horizontal direction,

the rubber solution is supplied in a direction at a right angle or an acute angle with respect to the direction in which the warm water flows,

the superheated steam is supplied in a direction in which the warm water flows.

4. The method for producing pellets according to any one of claims 1 to 3, wherein the superheated steam has a temperature of 140 to 300 ℃ and a pressure of 0.4 to 10 MPa.

5. The method for producing pellets according to any one of claims 1 to 4, wherein the temperature of the warm water is 70 ℃ or higher and the flow rate is 0.1 to 10 m/s.

6. A method for producing a block-shaped body, comprising a step of producing a pellet by using the method for producing a pellet according to any one of claims 1 to 5.

Technical Field

The present invention relates to a method for producing pellets and a method for producing block-shaped bodies (balls).

Background

Conventionally, a steam stripping method has been known as a method for producing pellets (for example, see patent document 1).

Specifically, when the solvent contained in the rubber solution is removed after the rubber solution and the pressurized steam are supplied in the warm water, that is, when the solvent removal is performed, a warm water slurry in which the aggregates are dispersed is formed. Next, when warm water is separated from the warm water slurry using a sieve, pellets are obtained. Then, when the pellets are dehydrated, dried, and molded, a block is formed.

Disclosure of Invention

Problems to be solved by the invention

However, the conventional method has a problem that aggregates adhere to the screen to cause clogging of the screen hole and the block body is colored. This is considered to be because the pellets have a large amount of volatile components and high adhesiveness. Specifically, aggregates containing a large amount of volatile components tend to adhere to the screen, and therefore clogging of the screen holes occurs. Further, when the pellets are dried, the pellets containing a large amount of volatile components tend to adhere to the dryer, and therefore, the rubber constituting the pellets is thermally deteriorated, and the block-shaped body is colored.

An object of one embodiment of the present invention is to provide a method for producing granules capable of suppressing the occurrence of clogging in screen holes and suppressing the coloring of block-shaped bodies.

Means for solving the problems

One embodiment of the present invention is a method for producing pellets, including the steps of: a rubber solution and superheated steam are supplied to warm water flowing in a predetermined direction, and the rubber solution is brought into contact with the superheated steam.

The warm water preferably contains a dispersant.

The hot water preferably flows in a horizontal direction, the rubber solution is supplied in a vertical direction, and the superheated steam is supplied in a horizontal direction.

The preferred temperature of the superheated steam is 140-300 ℃ and the pressure is 0.4-10 MPa.

The temperature of the warm water is preferably 80 ℃ or higher, and the flow rate is preferably 0.1 to 10 m/s.

Another embodiment of the present invention is a method for producing a block-shaped body, including a step of producing a pellet by using the above-described method for producing a pellet.

Effects of the invention

According to one embodiment of the present invention, a method for producing granules can be provided, which can suppress the occurrence of clogging in the screen holes and suppress the coloring of the block-shaped bodies.

Drawings

Fig. 1 is a schematic view showing one example of a pellet manufacturing apparatus used in manufacturing pellets.

Fig. 2A is a schematic side view showing an example of the nozzle of fig. 1.

Fig. 2B is a schematic rear view showing an example of the nozzle of fig. 1.

Fig. 3 is a schematic side view showing a modification of the nozzle of fig. 1.

Detailed Description

The following describes embodiments for carrying out the present invention.

< method for producing pellets >

A method for producing rubber-containing pellets using the pellet production apparatus 100 (see fig. 1) will be described as an example of the method for producing pellets according to the present embodiment.

First, a monomer as a constituent unit of rubber is polymerized by a known solution polymerization method to prepare a rubber solution R.

The rubber is not particularly limited, and examples thereof include acrylic rubber, isoprene rubber, styrene-butadiene rubber (SBR), low-cis butadiene rubber, high-trans butadiene rubber, styrene-isoprene rubber, butadiene-isoprene rubber, styrene-isoprene-butadiene rubber, ethylene-propylene-diene rubber, styrene-acrylonitrile-butadiene rubber, polyisoprene-SBR block copolymer, polystyrene-polybutadiene-polystyrene triblock copolymer, epichlorohydrin rubber, fluorine rubber, silicone rubber, ethylene-propylene rubber, and urethane rubber.

The rubber may be modified at its terminal or molecular chain with at least 1 kind of modifying group such as amino group, hydroxyl group, alkoxysilyl group, silanol group, etc.

Subsequently, the rubber solution R is transferred to the rubber solution tank 110. Here, the viscosity may be adjusted by adding a solvent to the rubber solution before the rubber solution is transferred to the rubber solution tank 110. When the rubber has low dispersibility in warm water described later, a dispersant described later may be added to the rubber solution R.

The rubber solution transferred to the rubber solution tank 110 may be stirred by a stirrer 111 provided in the rubber solution tank 110 as necessary.

Subsequently, the rubber solution R and the superheated steam S are supplied to the nozzle 121 provided on the side surface of the desolventizing tank 120₁And warm water W. At this time, the rubber solution R may be supplied from the bottom of the rubber solution tank 110 by the pump 112.

Superheated steam S₁Is high temperature steam generated by heating saturated steam.

Fig. 2A and 2B show an example of the nozzle 121. Fig. 2A and 2B are a side view and a rear view, respectively.

The nozzle 121 is provided with a hot water supply part 121a on the bottom surface, a superheated steam supply part 121b on the side surface, and a rubber solution supply part 121c on the top surface.

The hot water W is supplied from the hot water supply portion 121a to the inside of the nozzle 121 in the vertical direction (upward in the drawing), and then flows in the horizontal direction (rightward in the drawing).

In addition, within the scope of the present specification and claims, the horizontal direction means a range of ± 10 ° from the horizontal direction.

Superheated steam S₁The superheated steam is supplied from the superheated steam supply part 121b to the hot water W flowing in the horizontal direction inside the nozzle 121 in the direction in which the hot water W flows (rightward in the drawing). This increases the moving speed of the produced pellets C, and the pellets C are less likely to collide with each other. As a result, the aggregation of the granules C can be suppressed.

The rubber solution R is supplied from the rubber solution supply portion 121c into the hot water W flowing in the horizontal direction inside the nozzle 121 in a direction at right angles to the direction in which the hot water W flows (downward in the drawing). As a result, in the horizontally flowing warm water W, the rubber solution R and the superheated steam S₁Upon contact, the pellets C are formed,a slurry in which the aggregates C are dispersed is produced. Therefore, the occurrence of clogging in the screen holes can be suppressed, and the coloring of the block-shaped bodies can be suppressed. This is believed to be due to the reduction in volatile components of the pellets C. As a result, the pellets C do not easily adhere to the screen. Further, when the pellets C are dried, the pellets C are less likely to adhere to the dryer, and the rubber contained in the pellets C is less likely to thermally degrade.

The superheated steam S is supplied in the direction of the flow of the hot water W₁And the direction of the rubber solution R as long as the rubber solution R and the superheated steam S can be caused to flow₁The contact with the flowing hot water W is not particularly limited.

For example, the superheated steam S may be supplied in a direction forming an acute angle with respect to the flow direction of the warm water W₁。

Further, the rubber solution R may be supplied in a direction at an acute angle with respect to the direction in which the warm water W flows. This further increases the moving speed of the produced pellets C, and the pellets C are less likely to collide with each other. As a result, the aggregation of the granules C can be further suppressed.

Fig. 3 shows a modification of the nozzle 121.

The nozzle 121A has the same configuration as the nozzle 121 except that a hot water supply unit 121A is provided on the side surface, and a superheated steam supply unit 121b and a rubber solution supply unit 121c are provided on the top surface.

The hot water W is supplied from the hot water supply unit 121a to the inside of the nozzle 121 in the horizontal direction (rightward in the drawing), and then flows in the horizontal direction (rightward in the drawing).

Superheated steam S₁The superheated steam is supplied from the superheated steam supply unit 121b in the vertical direction (downward in the drawing) to the hot water W flowing in the horizontal direction inside the nozzle 121.

The rubber solution R is supplied from the rubber solution supply portion 121c in the vertical direction (downward in the drawing) to the hot water W flowing in the horizontal direction inside the nozzle 121. As a result, in the horizontally flowing warm water W, the rubber solution R and the superheated steam S₁Upon contact, the aggregates C are formed, resulting in a slurry having the aggregates C dispersed therein.

Superheated steam S₁The temperature of (A) is preferably 140 to 300 ℃, more preferably 180 to 250 ℃, and particularly preferably 190 to 2At 20 ℃. When the steam S is superheated₁When the temperature of (2) is 140 ℃ or higher, the occurrence of clogging in the sieve holes can be suppressed, and the coloring of the block body can be suppressed. On the other hand, when the superheated steam S₁When the temperature of (3) is 300 ℃ or lower, the cost can be reduced from the viewpoint of suppressing the coloring of the block-shaped bodies and the heat-resistant design of the apparatus for producing pellets 100.

Superheated steam S₁The pressure of (A) is preferably 0.4 to 10MPa, more preferably 0.9 to 3MPa, and particularly preferably 1 to 2 MPa. When the steam S is superheated₁When the pressure of (2) is 0.4MPa or more, the occurrence of clogging in the screen holes can be suppressed, and the coloring of the block-shaped body can be suppressed. On the other hand, when the superheated steam S₁When the pressure of (d) is 10MPa or less, the cost can be reduced from the viewpoint of the pressure-resistant design of the apparatus 100 for producing pellets.

The flow rate of the warm water W is preferably 0.1 to 10m/s, more preferably 0.5 to 3m/s, and particularly preferably 0.5 to 1 m/s. When the flow rate of the hot water W is 0.1m/s or more, the occurrence of clogging in the sieve holes can be suppressed, and the coloring of the block-shaped bodies can be suppressed. On the other hand, when the flow velocity of the hot water W is 10m/s or less, the cost can be reduced from the viewpoint of designing the apparatus 100 for producing pellets.

The flow rate of the hot water W can be determined by dividing the supply amount of the hot water W per unit time by the cross-sectional area of the nozzle 121.

The temperature of the hot water W is preferably 70 ℃ or higher, and more preferably 80 ℃ or higher. When the temperature of the hot water W is 70 ℃ or higher, the occurrence of clogging in the sieve holes can be suppressed, and the coloring of the block-shaped bodies can be suppressed.

The upper limit of the temperature of the hot water W is not particularly limited, but is preferably 120 ℃.

The warm water W preferably contains a dispersant. This can prevent clogging of a pipe for conveying the slurry after solvent removal from the bottom of the desolventizing tank 120 to the top of the desolventizing tank 140.

Here, when the hot water W contains a dispersant having a cloud point, the temperature of the hot water W is preferably equal to or higher than the cloud point of the dispersant.

The content of the dispersant in the hot water W is preferably 2 to 70ppm, and more preferably 3 to 40 ppm. When the content of the dispersant in the hot water W is 2ppm or more and 70ppm or less, clogging of a pipe for conveying the slurry after the solvent removal from the bottom of the desolventizing tank 120 to the top of the desolventizing tank 140 can be further suppressed.

As the dispersant, a nonionic surfactant, an anionic surfactant, a cationic surfactant, an amphoteric surfactant, or the like can be used.

Examples of the nonionic surfactant include: block copolymers of 2 or more alkylene oxides such as ethylene oxide-propylene oxide block copolymers; polyoxyalkylene ether compounds such as polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene octylphenyl ether, and polyoxyethylene nonylphenyl ether obtained by stepwise addition polymerization (polymerization) of alkylene oxide with higher alcohols having 5 to 50 carbon atoms such as lauryl alcohol, cetyl alcohol, stearyl alcohol, and oleyl alcohol, alkylphenols such as octylphenol, and alkylnaphthols such as butylnaphthol and octylnaphthol; polyoxyalkylene glycol fatty acid ester compounds such as polyoxyethylene glycol monolaurate, polyoxyethylene glycol monopalmitate, polyethylene glycol monostearate, polyethylene glycol distearate, and polyethylene glycol monooleate obtained by stepwise addition polymerization of an alkylene oxide to a higher fatty acid having 5 to 50 carbon atoms such as lauric acid, palmitic acid, stearic acid, and oleic acid; glycerol monostearate, glycerol monooleate, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan distearate, sorbitan tristearate, sorbitan monooleate, sorbitan dioleate, monolaurate, monostearate, monolaurate, monopalmitate, sorbitan monostearate, hexitan distearate, hexitan monostearate, hexitan distearate, tristearate, hexitan monooleate, hexitan monostearate, and polycondensates thereof, and esters of polyhydric alcohols having 3 or more hydroxyl groups in the molecule and higher fatty acids having 5 to 50 carbon atoms, Polyhydric alcohol fatty acid ester compounds such as hexitol anhydride dioleate; polyoxyalkylene polyol fatty acid ester compounds such as polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan distearate, polyoxyethylene sorbitan monooleate, polyoxyethylene monobactam monopalmitate, polyoxyethylene monobactam monostearate, polyoxyethylene monobactam monooleate, polyoxyethylene hexitol monolaurate and polyoxyethylene hexitol monostearate, which are obtained by stepwise addition polymerization of the polyol fatty acid ester compound and an alkylene oxide; polyoxyalkylene alkylamine compounds such as polyoxyethylene stearylamine and polyoxyethylene oleylamine; alkyl alkanol amide compounds, and the like.

Among these, polyoxyalkylene-based compounds such as block copolymers of 2 or more alkylene oxides, polyoxyalkylene ether-based compounds, polyoxyalkylene glycol fatty acid ester-based compounds, polyoxyalkylene polyol fatty acid ester-based compounds, and polyoxyalkylene alkylamine compounds are preferable, and particularly, oxyethylene oxypropylene block copolymers, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene nonylphenyl ether, polyethylene glycol monostearate, polyoxyethylene sorbitan monostearate, and polyoxyethylene stearylamine are preferable.

Examples of the anionic surfactant include carboxylate salts such as aliphatic monocarboxylic acid salts, polyoxyethylene alkyl ether carboxylate salts, N-acyl sarcosinate salts, and N-acyl glutamate salts; sulfonates such as dialkyl sulfosuccinate, alkyl sulfonate, α -olefin sulfonate, linear alkyl benzene sulfonate, branched alkyl benzene sulfonate, naphthalene sulfonate-formaldehyde condensate, alkyl naphthalene sulfonate, and N-methyl-N-acyl taurate; sulfate salts such as alkyl sulfate, polyoxyalkylene ether sulfate and oil sulfate; phosphoric acid esters such as alkyl phosphate, polyoxyethylene alkyl ether phosphate, and polyoxyethylene alkylphenyl ether phosphate.

Examples of the cationic surfactant include monoalkylamine salts, dialkylamine salts, trialkylamine salts, alkyltrimethylammonium chlorides, alkyltrimethylammonium bromides, alkyltrimethylammonium iodides, dialkyldimethylammonium chlorides, dialkyldimethylammonium bromides, and alkylbenzalkonium chlorides.

Examples of the amphoteric surfactant include alkyldimethylaminoacetic acid betaine, alkyldimethylacetic acid betaine, alkyldimethylcarboxymethylbetaine, alkyldimethylcarboxymethylaminomethylaminium betaine, alkyldimethylacetoamide, fatty acid amidopropyldimethylaminoacetic acid betaine, alkylamidopropyldimethylglycine, alkylamidopropyldimethylacetoamide, 2-alkyl-1- (2-hydroxyethyl) imidazolinium-1-acetate, alkyldiaminoethylglycine, dialkyldiaminoethylglycine, and alkyldimethylamine oxide.

The dispersant may be used alone, or two or more of them may be used in combination.

The content of the rubber in the rubber solution R is not particularly limited, but is preferably 10 to 50% by mass.

Next, the slurry in which the pellets C are dispersed, which is generated at the nozzle 121, is conveyed to the desolventizing tank 120. At this time, the slurry transferred to the desolventizing tank 120 is stirred by the stirrer 122, and the insulating steam S is supplied from the lower portion of the desolventizing tank 120 in the vertical direction (upward in the drawing)₂The solvent is removed by stripping. As a result, a part of volatile organic compounds (solvent, unreacted monomers, etc.) contained in the slurry in which the aggregates C are dispersed is evaporated.

Here, the volatile organic compound evaporated by the solvent removal is condensed by the condenser 130, and then the solvent is recovered and reused as necessary.

Heat-preserving steam S₂The temperature of (A) is not particularly limited, but is preferably 100 to 190 ℃.

Heat-preserving steam S₂The pressure of (A) is not particularly limited, but is preferably 0.1 to 1 MPa.

Then, the slurry after solvent removal is passed throughThe pump 123 is transferred from the bottom of the desolventizing tank 120 to the top of the desolventizing tank 140. At this time, the slurry transferred to the desolventizing tank 140 is stirred by the stirrer 141, and the insulating steam S is supplied from the bottom of the desolventizing tank 140 in the vertical direction (upward in the drawing)₂The solvent is removed by stripping. As a result, a part of the volatile organic compounds contained in the slurry in which the aggregates C are dispersed is evaporated.

Here, the volatile organic compound evaporated by the solvent removal is condensed by the condenser 130, and then the solvent is recovered and reused as necessary.

The desolventized slurry is then transferred from the bottom of the desolventizing tank 140 to the top of the desolventizing tank 150 by the pump 142. At this time, the slurry transferred to the desolventizing tank 150 is stirred by the stirrer 151, and the insulating steam S is supplied from the lower portion of the desolventizing tank 150 in the vertical direction (upward in the drawing)₂The solvent is removed by stripping. As a result, the remaining part of the volatile organic compounds contained in the slurry in which the aggregates C are dispersed is evaporated, and warm water slurry in which the aggregates C are dispersed is generated.

Here, the volatile organic compound evaporated by the solvent removal is condensed by the condenser 130, and then the solvent is recovered and reused as necessary.

The number of the desolvation tanks is not limited to 3, and can be appropriately changed so that the volatile organic compounds contained in the slurry in which the aggregates C are dispersed can be sufficiently removed.

Next, the warm water slurry is transferred from the bottom of the desolventizing tank 150 to the screen 160 by the pump 152, separated into slurry (Serum) water (warm water) and pellets C. As a result, the slurry water is recovered in the slurry water tank 170, and the pellets C are recovered in the pellet tank 180.

Here, the slurry water collected in the slurry tank 170 is stirred by the stirrer 171 as necessary, transferred from the bottom of the slurry tank 170 by the pump 172, and mixed with the hot water W for reuse.

The inclination angle of the sieve 160 is not particularly limited, and is preferably 30 ° to 75 °.

The pellets C recovered in the pellet tank 180 are stirred by a stirrer 181 and transported from the bottom of the pellet tank 180 by a pump 182, if necessary, to be used for producing a block-shaped body.

< method for producing Block body >

The block-shaped body contains rubber, and can be produced by a known method using the pellet C produced by the method for producing a pellet of the present embodiment.

For example, the pellets C are dehydrated and dried, and then molded using a mold having a predetermined shape to produce a block-shaped body.

The pellets C may be crushed and then dehydrated.

As the dehydrator used for dehydrating the pellets C, for example, a screw press type dehydrator can be used.

As the dryer for drying the dehydrated pellets C, for example, an expansion type extrusion dryer, a vibration dryer, or the like can be used.

As the molding machine for molding the dried pellets C, a known molding machine can be used.