JP2923079B2 - Plastics-water slurry composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a plastics-water slurry composition.

[0002]

2. Description of the Related Art In recent years, Japan's plastics production volume has been 12
It is expected to exceed one million tons, and the amount discharged as plastics waste is said to be more than five million tons. Plastics waste is generally classified into general plastic waste discharged as household waste and industrial plastic waste discharged from various production or processing plants and distribution processes. Somewhat high.

[0003] Plastics in general plastics wastes are of many types and have various shapes. In general, there are many plastics mainly composed of film-like polyethylene and polypropylene and dish-like polystyrene used for food packaging. However, these plastics are difficult to separate from general waste and are expensive, so there are few places where they are reused by local governments, and at present, they are incinerated or landfilled.

[0004] On the other hand, industrial plastic wastes are separated at the discharge source and those whose properties are clear are simply recycled, and similar plastics contaminants are compositely recycled into civil engineering and building materials such as piles and panels. ing. Those that are difficult to separate are used as fuel or incinerated as they are.

[0005] Industrial plastic wastes used as fuels include polyolefin resins (PE, PP), polystyrene resins, PET resins and the like. If these plastics are mixed and discharged, or if they are composited with paper or fiber, they cannot be used as recycled materials, so these wastes are used as fuel. These plastic wastes contain a large amount of thermoplastic resin and are melted by heating and used as briquettes or pellets of solid fuel.

However, conventional solid fuels made of plastics waste have a high calorific value and an excessive combustion speed, so that the high heat accelerates the wear of the combustion furnace or is incomplete due to a partial lack of oxygen. Often it was burning. In addition, there is a disadvantage that the plastics itself melts during the combustion and adheres to the furnace wall, or the molten plastics flows and hinders the combustion. Further, solid fuels are usually burned in a fixed hearth such as a stoker due to their large particle size, and cannot be sprayed and burned by a burner, so that they are difficult to handle as fuel.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a plastics-water slurry composition which has good flowability and can be handled as a liquid fuel.

[0008]

That is, the present invention relates to a method of copolymerizing a powder of plastics and a monomer selected from at least one of the following monomer groups (A) and (B) or a monomer group (A The present invention relates to a plastics-water slurry composition containing a water-soluble copolymer obtained by copolymerization of at least one monomer selected from each group of the following: (A) maleic acid, maleic acid monoester , Acrylic acid or a salt thereof and methacrylic acid or a salt thereof (B) a polymerizable monomer containing a sulfone group (C) a vinyl monomer copolymerizable with the monomer of the above (A) and / or (B)

The plastics that can be used in the present invention may be thermoplastic or thermosetting as long as they are flammable, but resins that do not dissolve or swell in water are preferred. Olefin polymers such as polypropylene, polyisobutylene, and ethylene vinyl acetate copolymers; ethylene addition polymers such as polystyrene; (b) acrylonitrile-butadiene-styrene copolymer
(ABS resin), acrylonitrile-styrene copolymer
(AS resin), acrylic resin such as poly (meth) acrylic acid (ester), (c) synthetic rubber or natural rubber such as polybutadiene, polyisoprene, butadiene-styrene copolymer, (d) polyacetal, polyester, polyamide (E) Thermoplastic resins such as vinyl chloride resins such as vinyl chloride and vinylidene chloride; and (f) phenol resins and (g) urea resins. And a thermosetting resin such as a melamine resin. In particular, in addition to polyolefin waste plastics such as polyethylene and polypropylene and polystyrene, which are frequently discharged into industrial plastic waste, vinyl chloride waste plastics and waste tires are often used. These plastics may be used alone or in combination.

[0010] The plastics used in the present invention include waste plastics discarded after various plastics molded articles have been used temporarily or for a long period of time, or off-molded products, burrs generated during molding of various plastics, What is necessary is just a remaining part of a cut or an ear part. In addition, solidified plastics (such as briquettes and pellets) reduced in volume of plastics separated from general waste can be used.

These plastics are crushed or pulverized to a particle size of 2,000 μm or less, preferably 1.0 to 1.0 μm.
It is used as a powder having a size of 00 μm or less, more preferably 500 μm or less. Plastics powder with particle size of 2,000
If it exceeds 0 μm, a slurry having good fluidity cannot be obtained,
Spray combustion by the burner becomes impossible.

The shape of the plastics powder is preferably spherical, elliptical or cubic, and the ratio of the major axis to the minor axis is 10%.
The rod-shaped or strip-shaped particles described above are not preferable for the present invention.

[0013] Plastics powder is usually obtained by crushing crushed plastics, but soft thermoplastic waste plastics such as films and styrofoam are pelletized solids reduced in volume by compression melting and solidification or rotary kiln. Crush. Examples of the pulverization method include hammer mills, bin mills, and jet mills as dry pulverization methods, and ball mills, vibrating ball mills, and centrifugal ball mills as wet pulverization methods. In particular, a jet mill or a vibrating ball mill is suitable as a method for obtaining fine powder. In a jet mill, a method of collecting fine powder pulverized by a scrubber with water containing a dispersant of the present invention described below is effective.

In the present invention, copolymerization of at least one monomer selected from each of the following monomer groups (A) and (B) or at least one monomer selected from each of the monomer groups (A) to (C): A water-soluble copolymer obtained by copolymerization of the monomers selected is used as a dispersant: (A) maleic acid, maleic acid monoester, acrylic acid or a salt thereof and methacrylic acid or a salt thereof (B) a sulfone group Containing polymerizable monomer (C) Vinyl monomer copolymerizable with the above-mentioned monomer (A) and / or (B)

The component (A) includes maleic anhydride, maleic acid, maleic acid monomethyl ester, maleic acid monoethyl ester, maleic acid monobutyl ester, maleic acid monooctyl ester, acrylic acid or an alkali metal salt thereof and / or methacrylic acid. Examples thereof include an acid or an alkali metal salt thereof.

The component (B) is a polymerizable monomer containing a sulfone group, such as vinyl sulfonic acid, styrene sulfonic acid, allyl sulfonic acid, methallyl sulfonic acid, 2-acrylamido-2-methylpropane sulfonic acid, and 2-sulfoethyl (meth ) Acrylate, 3-sulfopropyl (meth) acrylate, 2-sulfopropyl (meth) acrylate, 1
-Sulfopropan-2-yl (meth) acrylate, 4-
Various sulfonic acid salts such as sulfobutyl (meth) acrylate can be exemplified.

The component (C) is a vinyl monomer copolymerizable with the component (A) or (B), and includes methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, and octicle (meth) acrylate. Acrylate, dodecyl (meth) acrylate, oleyl (meth) acrylate, stearyl (meth) acrylate, benzyl (meth) acrylate, nonylphenyl (meth) acrylate and other (meth) acrylates; hydroxyethyl (meth) acrylate, hydroxy Propyl (meth) acrylate, (meth) acrylates having a hydroxyl group such as polyethylene glycol (meth) acrylate; (meth) acrylate of methoxypolyethylene glycol, (meth) acrylate of methoxypolypropylene glycol,
Methoxy polypropylene and polyethylene glycol
(Meth) acrylic acid ester, (meth) acrylic acid ester of ethoxypolyethylene glycol, (meth) acrylic acid ester of ethoxypolypropylene glycol, (meth) acrylic acid ester of propoxypolyethylene glycol, and alkoxypolyethylene glycol having up to 30 carbon atoms (Meth) acrylates and phenoxy polyethylene glycol (meth) acrylates,
Benzyloxypolyethylene glycol (meth) acrylate, nonylphenoxypolyethylene glycol (meth) acrylate, cyclohexoxypolyethylene glycol (meth) acrylate, etc. Polyalkylene glycol having a degree of chain polymerization of 1 to 100 (meth) acrylates; (meth)
Acrylamide, various (meth) acrylamides such as N-methylol (meth) acrylamide; styrene, aromatic vinyl compounds such as p-methylstyrene; vinyl acetate,
Propenyl acetate, vinyl chloride and the like can be mentioned.

Particularly preferred monomers among the above components (A) to (C) are the aforementioned compounds as component (A),
Component (B) is vinylsulfonic acid, allylsulfonic acid, styrenesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, and component (C) is methyl (meth) acrylate, styrene, acrylamide,
Vinyl acetate, methoxypolyethylene glycol (meth)
An acrylic acid ester, a (meth) acrylic acid ester of methoxypolypropylene glycol, and a (meth) acrylic acid ester of ethoxy polyethylene glycol.

The component ratio of the monomers in the water-soluble copolymer used in the present invention depends on the monomers to be reacted and is not particularly limited, but the component (A) is 20 to 90 mol% and the component (B) is not limited. The ratio is generally 0 to 80 mol% and the component (C) is 0 to 50 mol%. However, (A), (B) and
The total of (C) is 100 mol%. If these monomer components (A), (B) and (C) are used outside the range of the mixing ratio, the dispersibility of the resulting water-soluble copolymer will be reduced.

Examples of the water-soluble copolymer used in the present invention include a maleic anhydride-styrene copolymer salt, a (meth) acrylic acid-styrene sulfonic acid copolymer salt, a (meth) acrylic acid- Salt of vinyl sulfonic acid copolymer, salt of (meth) acrylic acid-2-acrylamido-2-methylpropanesulfonic acid copolymer, (meth) acrylic acid-styrenesulfonic acid-methyl (meth) acrylate copolymer A salt of a (meth) acrylic acid-methoxypolyethylene glycol (meth) acrylate ester copolymer, a maleic acid-methoxypolyethylene glycol (meth) acrylate ester copolymer salt, a (meth) acrylic acid- Styrenesulfonic acid-methoxypolyethylene glycol (meth)
A salt of an acrylic ester copolymer may, for example, be mentioned.

In order to produce the water-soluble copolymer used in the present invention, the monomer component may be copolymerized by a known method using various polymerization initiators. The copolymerization is water,
It can be carried out in an organic solvent such as a lower alcohol, aromatic or aliphatic hydrocarbon or ketone, or by a method such as bulk polymerization.

The water-soluble copolymer thus obtained is generally used after being neutralized with a basic substance. Examples of the basic substance include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, aqueous ammonia, and organic amines.

The molecular weight of the water-soluble copolymer used in the present invention can be in a wide range, but is usually from 1,000 to 1,000.
500,000, preferably 5,000 to 200,000
It is. Plastics obtained with less than 1,000
The dispersibility of the water slurry composition becomes worse, while 500,
If it exceeds 000, the obtained plastics-water slurry composition will have cohesiveness.

The dispersant for the plastics-water slurry composition of the present invention may be a compound having one active hydrogen having a relatively large hydrophobic group, such as an alkylphenol or a higher alcohol, in addition to the water-soluble copolymer. Moles of nonionic surfactant or a compound having two or more active hydrogens such as glycerin, sorbite, ethylenediamine, polyethyleneimine, etc. to which propylene oxide and ethylene oxide have been added to a molecular weight of 20
00 or more block copolymers can be used in combination.
It is preferred that the amount of these additives be no more than 30% by weight, preferably no more than 20% by weight of the total amount of additives.

In the present invention, the above-mentioned water-soluble copolymer may be dissolved in water in advance and then added to the finely powdered plastics, or may be added later to the mixture of the plastics and water. .

The amount of the water-soluble copolymer is not particularly limited. However, usually, for example, when the average particle size of the finely powdered plastics is 100 μm, it is 0% based on the plastics-water slurry composition. 0.1 to 3.0% by weight, preferably 0.2 to 1.0% by weight. If the amount exceeds 3.0% by weight, the viscosity-lowering ability does not change and it is uneconomical. On the other hand, if it is less than 0.1% by weight, there is almost no viscosity-lowering ability.

Although the amount of the plastics powder is not particularly limited, it is usually 30 to 80% by weight, preferably 40 to 70% by weight based on the plastics-water slurry composition.
% By weight. If the amount exceeds 80% by weight, it is extremely difficult to make a slurry, while if it is less than 30% by weight, direct combustion is difficult due to heat of evaporation of water.

[0028]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

Examples 1 to 12 and Comparative Examples 1 to 4 A mixed plastic of about 3: 2 polyethylene and polypropylene crushed to about 5 mm or less is pulverized to 0.2 mm or less, and fine plastics powder having an average particle diameter of 50 μm. I got A predetermined amount of the plastics fine powder was added to an aqueous solution of the dispersant shown in Table 1 with stirring, and then mixed with a homomixer to obtain a plastics fine powder-water slurry having a fine powder weight concentration of 62% by weight. The viscosity of this slurry was measured at 25 ° C. with a Haake rheometer.

[0030]

[Table 1]

[0031]

[Table 2]

[0032]

[Table 3]

As is clear from the results shown in Table 1, all of the examples to which the dispersant of the present invention was added had better fluidity than the comparative example, and did not cause sedimentation or floating separation of the fine plastics powder. .

[0034]

The plastics-water slurry composition of the present invention has good fluidity and can be handled as a liquid fuel. Further, the concentration of the plastics powder can be improved by 10 to 30% by weight as compared with the conventional product not containing the dispersant of the present invention. The present invention provides a plastics-water slurry composition that can be used as a plastics-mixed liquid fuel using general and industrial plastics wastes, and reduces plastics wastes that contribute to environmental destruction. It can be effectively reused as fuel resources. The plastics-water slurry composition obtained according to the present invention can be handled not only as a liquid in transportation and storage, but also in spray combustion by a burner in combustion. Further plastics of the present invention - water slurry composition can reduce the concentration of NO _x in the exhaust gas while preventing excessive temperature, incomplete combustion with water. The plastics-water slurry composition of the present invention can be co-fired with fuels such as heavy oil, pulverized coal, coal-water slurry (CWM), and coal-oil slurry (COM).

Continuation of the front page (56) References JP-A-53-110608 (JP, A) JP-A-54-58710 (JP, A) JP-A-60-67592 (JP, A) JP-A-4-345689 (JP) JP-A-48-44303 (JP, A) JP-A-50-39303 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C10L 1/00-1/32

Claims (3)

(57) [Claims] 1. A copolymer of a powder of plastics and at least one monomer selected from each of the following monomer groups (A) and (B) or monomer groups (A) to (C):
A plastics-water slurry composition containing a water-soluble copolymer obtained by copolymerization of at least one monomer selected from each group of: (A) maleic acid, maleic acid monoester, acrylic acid or a salt thereof And methacrylic acid or a salt thereof (B) a polymerizable monomer containing a sulfone group (C) a vinyl monomer copolymerizable with the above-mentioned monomer (A) and / or (B) 2. 30 to 80% by weight of plastics powder
The plastics-water slurry composition according to claim 1, comprising 0.1 to 3.0% by weight of a water-soluble copolymer. 3. The plastics powder has a particle size of 2,000.
The plastics-water slurry composition according to claim 1, which has a thickness of 0 µm or less.