JPS6329910B2 - - Google Patents

Description

[Detailed Description of the Invention] This invention provides a coating for waterproofing, dustproofing, etc. of coal, coke, iron ore, minerals such as river sand, wood powder, etc. when deposited in open piles over a long period of time. Regarding paints for use.

In general, coal, coke, wood powder, and the like are often piled up in open piles at steel mills, gas plants, paper mills, and the like. However, during storage, these deposits tend to stir up dust in the wind, making the work environment worse, and when it rains, the fine powder is washed away, resulting in deposit loss. In addition, especially in the case of coal, coke, iron ore, etc., when they are piled up in the open, they absorb water and the water content in the sediment increases, and when they are heated or burned, energy loss due to evaporative heat loss of water increases. However, there are also disadvantages such as fluctuations in calorific value, making it difficult to control heating or combustion.

An excellent way to solve these problems is to
A method of forming a water-insoluble coating film on the surface of open deposits by coating the surface of open deposits with a paint containing powder or granules made of the same or similar material as the filler and drying it. has already been proposed. According to this method, scattering of dust, runoff due to rainfall, and increase in water content can be prevented.

However, in the above method, although the water-insoluble coating prevents moisture from entering from the outside, moisture that has entered due to special factors such as moisture pre-existing in the deposit or moisture that has penetrated from the floor surface accumulates. Trapped in materials, drying of deposits is significantly inhibited. For this reason, the above-mentioned point becomes a particular problem in deposits that are heated or burned, such as coal, coke, or iron ore.

As a result of extensive research in view of the above points, the inventors set the blending ratio of the solute, which is a film-forming component in the paint component, and the filler within a specific range, while achieving a specific amount of water repellency. By adding the drug,
We discovered that it is possible to obtain a coating film that has both water repellency, which prevents the infiltration of liquid moisture due to rainfall, and moisture permeability, which allows moisture to evaporate and dissipate from inside the deposit, and led to the creation of this invention. It is something.

That is, the present invention applies 1,000 to 1,000 parts of powder or granules made of the same or similar material as the field deposits to 100 parts by weight of the solute that becomes water-insoluble upon drying.
An open deposit consisting of a first component containing 5000 parts by weight and a second component containing 0.03 to 3 parts by weight of a water repellent agent based on 100 parts by weight of the total amount of the solute and powder. This relates to coating paints.

The field deposits applied to this invention include, for example, coal (powder), coke (powder), iron ore, minerals such as river sand, copper ore, coal rock, bauxite, other metal ores, or organic deposits such as wood powder. These include powdered products.

In this invention, the first component is preferably a water emulsion type solvent, but other organic solvent types may be used. In any case, the solute constituting each of these solutions is a material that becomes water-insoluble upon drying.

This solute material, particularly a water emulsion type solute material, contains a resin as a main material as well as optional components such as a film-forming agent, a thickener, an antifoaming agent, and a freeze-thaw stabilizer.

Typical examples of resins that are the main material of the solute include, in water emulsion systems, vinyl acetate polymers or their copolymers, acrylic esters, methacrylic esters, or their copolymers with styrene; There are copolymers of butadiene and styrene, copolymers of butadiene and acrylonitrile, and organic solvent-based products such as styrenated alkyd resins, xylene resin-modified alkyds,
Examples include copolymers of vinyl chloride and vinyl acetate.

Specific examples of film-forming aids and thickeners that are usually added when making water emulsion-based paints include butyl cellosolve, butyl cellosolve acetate, butyl carbitol, carbitol acetate, hexylene glycol, dibutyl Examples include phthalate and dioctyl phthalate, and thickeners include methylcellulose, ethylcellulose, polyvinyl alcohol, hydroxyethylcellulose, carboxymethylcellulose, sodium polyacrylate, casein, and starch.

The paint of this invention usually contains 7 to 60 of these solutes.
% by weight of a solution such as a water emulsion or an organic solvent solution such as toluene or methyl ethyl ketone, by mixing powder or granules (hereinafter referred to as filler) made of the same or similar material as the field deposit at a specific mixing ratio. is important, and by adding this filler, thixotropic properties are imparted to the paint, which prevents the paint itself from penetrating into the deposit as much as possible when applied to the surface of the deposit. , and by setting the blending ratio within a specific range, appropriate moisture permeability is imparted to the coating film.

As described above, such a filler is selected from materials that are the same as or similar to the open deposits, but may be any material that has the same function or use as the materials similar to the deposits. The particle size of the filler is preferably adjusted such that the maximum particle size is generally 20 mm or less, and 80% or more of the 5-mesh pass product and 20% or more of the 40-mesh pass product.

The blending ratio of the filler is 1000 to 5000 parts by weight, preferably 1500 to 5000 parts by weight, per 100 parts by weight of the solute in the solution.
It is 3000 parts by weight. A coating film with less than 1000 parts by weight will become dense and have insufficient moisture permeability, and conversely, if it exceeds 5000 parts by weight, the coating film will become too rough and allow liquid moisture such as rainwater to easily penetrate, resulting in poor moisture permeability. Appropriate.

The paint of the present invention has a first component which is made by blending a specific amount of filler with the solute of the solution described above, and a specific amount of filler with respect to the solid content of the first component, that is, the total amount of the solute and filler. Further water repellency is imparted to the moisture permeable coating film by using a second component containing a proportionate amount of a water repellency imparting agent.

Examples of the water repellency imparting agent include silicone, paraffin, and low-molecular polyethylene, which are used as the second component in the form of an emulsion using an appropriate emulsifier or in the form of a solution using an appropriate solvent.

This second component can be mixed with the first component and used as a one-component paint, or can be used as a one-component paint.
It is used as a two-component paint that is applied to the surface of the deposit and then recoated. That is, when the miscibility of the second component with the first component is good, the one-component paint may be used, and when the miscibility is poor, the two-component paint may be used. A one-component type is more advantageous in terms of workability because it only requires one coating.

The amount of water repellency imparting agent used is 0.03 to 100 parts by weight of the total amount of the solute and filler as the first component.
It should be 3 parts by weight, preferably 0.1 to 1.0 parts by weight. If the amount used is less than 0.03 parts by weight, sufficient water repellency will not be imparted to the paint film, and if it exceeds 3 parts by weight, the moisture permeability of the paint film will be inhibited, and especially if the above-mentioned one-component paint When this happens, the water-repellent agent may enter the interface of the filler and form a water-repellent film, which may reduce the strength of the coating film.

In order to apply the paint of this invention to the surface of open deposits, the dry coating thickness should be at least 1/10 of the maximum particle size of the filler, preferably at least the maximum particle size, by means such as spraying, flow coating, or troweling. The coating may be allowed to dry naturally. In addition, if the paint is a two-component type, the first component is applied and the second component is applied each time a coating film is formed.
Just apply the ingredients.

In this way, the open piles coated with the paint of the present invention can be prevented from scattering dust, runoff due to rain, and increase in water content even if left for a long time, and can be prevented from increasing in water content even after being left for a long time. Accordingly, the water content evaporates and a certain dry state is reached, and this state is maintained. Therefore, when deposits are collected and heated or burned, energy loss due to heat loss due to evaporation of moisture is reduced, and control operations thereof are also facilitated.

Examples and comparative examples of the present invention are shown below. In the following, parts and % mean parts by weight and % by weight, respectively.

Example 1 100 parts of a 50% water emulsion of a copolymer of butyl acrylate and styrene with a monomer composition of 65:35 was used as a solute, and as a solvent, 1.5 parts of a 4% aqueous solution of carboxymethyl cellulose, 2 parts of butyl cellosolve,
A solution was prepared by adding 0.8 parts of a 10% aqueous solution of sodium hexametaphosphate and 20 parts of water, and to this was added 2000 parts of coal powder of 5 mesh passes and 50 parts of paraffin wax.
% water emulsion to form the coating composition of the present invention.

When this paint was applied to the surface of an open pile of coal powder with a floor area of 5,400 m ² and a pile height of 18 m and allowed to air dry, a water-insoluble paint film with a dry thickness of approximately 3 mm was formed. . After about 6 months, no scattering or outflow of coal powder was observed in the deposit coated with this method. Furthermore, the water content, which was 120Kg/m ³ before coating, had decreased to 80Kg/m ³ .

Comparative Example 1 A coating paint was prepared in the same manner as in Example 1 except that the amount of coal powder was changed to 500 parts, and this paint was used to coat the surface of the same field deposit as in Example 1 with a water-insoluble coating. A coating film was formed. In this case, no scattering or outflow of coal powder was observed after approximately 6 months had passed, but the water content in the sediment was 115 kg/m ³ , almost the same as the water content before the coating film was formed.

Comparative Example 2 The amount of water emulsion as a water repellent agent was 100%.
A coating paint was prepared in exactly the same manner as in Example 1, except that the coating was used to form a water-insoluble coating film on the surface of the same field deposit as in Example 1. In this case, the strength of the coating film was significantly weakened, and areas of collapse were observed here and there about every month, and leakage was also observed.

Example 2 100 parts of a 50% water emulsion of a copolymer of 2-ethylhexyl acrylate, styrene and methacrylic acid with a monomer composition of 50:45:5, 50 parts of a 2% aqueous solution of hydroxyethyl cellulose, 10 parts of ethylene glycol, Antifoaming agent (Shin-Etsu Silicone KM-72)
A solution was prepared by adding 0.5 parts and 300 parts of water, and 1500 parts of iron ore powder of 10 mesh passes was mixed thereto to form the first solution of the paint of this invention. Apart from this, 2
A solution of 100 parts of silicone grease dissolved in 100 parts of toluene was prepared as the second liquid of the coating of the present invention.

The above first liquid paint was sprayed onto the surface of an open pile of iron ore powder with a floor area of 1000 m ² and a pile height of 8 m, and after it was allowed to air dry, the second liquid was further sprayed onto the surface. When dried naturally, a water-insoluble coating film with a dry thickness of 2 mm was obtained. After approximately 3 months had passed, no scattering or outflow of iron ore powder was observed in the deposit coated with this method, and the water content, which was 30 Kg/m ³ before coating, had decreased to 15 Kg/m ³ .

Example 3 100 parts of a 50% water emulsion of a copolymer of styrene and butadiene with a monomer composition of 30:70 was used as a solute, and 3 parts of ethyl cellosolve and water were used as a solvent.
A solution was prepared by adding 100 parts of the solution, and 1,200 parts of 2.5 mesh pass wood powder was mixed therewith to form the first solution of the paint of the present invention. Separately, an emulsion was prepared by emulsifying 50 parts of low molecular weight polyethylene in 100 parts of water and used as the second liquid of the coating material of this invention.

The above first liquid paint was sprayed onto the surface of a pile of wood flour with a floor area of 2,400 m ² and a pile height of 15 m, and then allowed to air dry, and then the second liquid was further sprayed onto the surface. After drying and air drying, a water-insoluble coating film with a dry thickness of about 5 mm was obtained. The deposit coated with this method showed no scattering or runoff of wood powder after approximately 2 months, and the water content, which was 150 kg/m ³ before coating, had decreased to 50 kg/m ^3. .

Claims (1)

[Scope of Claims] 1. A first component containing 1,000 to 5,000 parts by weight of powder or granules made of the same or similar material as field deposits to 100 parts by weight of a solute that becomes water-insoluble upon drying; A paint for coating field deposits, comprising a second component containing a water repellent agent in an amount of 0.03 to 3 parts by weight based on 100 parts by weight of the above-mentioned solute and powder. 2. The paint for coating field deposits according to claim 1, which is a one-component type in which the second component is mixed into the first component. 3. The paint for coating field deposits according to claim 1, which is a two-part type comprising a first component and a second component.