JPS6116681B2 - - Google Patents

Description

Detailed Description of the Invention This invention is a method of coating coal, coke, iron ore, minerals such as river sand, wood powder, etc., when depositing them in open piles over a long period of time. The present invention relates to a coating pretreatment agent for waterproofing, dustproofing, preventing oxidation caused by air, etc., and a coating method using the same.

In general, coal, coke, wood powder, etc. are often stored in open piles at steel mills, gas plants, paper mills, etc. However, during storage, these sediments tend to stir up dust in the wind, causing dust pollution in surrounding areas and causing sediment loss, and during rainfall, they flow into rivers and the sea, causing sewage. Excessive moisture content in sediments such as summer heat, coal, coke, iron ore, etc., causes disadvantages such as evaporative heat loss of water when the deposits are combusted.

An excellent way to solve these problems is to
A method has already been proposed in which a coating material containing a solute that becomes water-insoluble after drying is applied to the surface of open deposits, in particular, the above-mentioned paint containing powder and granules that are the same as or similar to those of open deposits is added as a filler. ing.

Although this method is extremely effective, the physical properties of the coating film formed vary depending on variations in surface conditions such as moisture content and particle size of the field deposits, as well as temperature, humidity, and weather at the time of coating. Moreover, the coating film cracked and chipped over time, which adversely affected the waterproofing, dustproofing, and other effects.

As a result of intensive studies from the above point of view, the inventors found that if a specific pre-treatment agent is sprayed on the surface of open deposits before coating the surface with coating paint, the surface condition of the deposits will improve. The inventors have discovered that the coating film properties are stable and of good quality despite variations in weather conditions during coating and coating, leading to the creation of this invention.

That is, the present invention relates to a first pretreatment agent for coating field deposits containing one or more of monohydric alcohols, polyhydric alcohols, and their derivatives as an active ingredient at a concentration of 0.05% by weight or more. Invention, the above pretreatment agent is applied to the surface of open deposits at a rate of 0.5~
This invention relates to a second invention characterized in that, after being sprayed at a rate of 6 kg/m ² , a coating paint containing a solute that becomes water-soluble after drying is applied.

The monohydric alcohols that are the active ingredients of the pretreatment agent of this invention include methanol, ethanol, n
-Butanol, n-propanol, isopropanol, etc.; polyhydric alcohols include propylene glycol, dipropylene glycol, polyethylene glycol, ethylene glycol, diethylene glycol, triethylene glycol, butanediol, 1,5-pentanediol, glycerin, dipropylene glycol, Examples include glycerin and trimethylolpropane.

In addition, as derivatives of polyhydric alcohols, ethylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether, ethylene glycol diethyl ether, ethylene glycol isopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monoacetate, ethylene glycol Examples include diacetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monoisopropyl ether, and diethylene glycol monobutyl ether.

The pretreatment agent of the present invention contains 0.05% by weight of the above-mentioned active ingredients, particularly preferably one or more of monohydric alcohols and dihydric alcohols, in a medium typically represented by water. As mentioned above, it is preferably contained at a concentration of 0.2 to 2% by weight.

This pretreatment agent may include water-soluble polymers such as polyester polyols and polyether polyols, vinyl acetate polymers or copolymers thereof, acrylic ester or methacrylic ester polymers, or combinations thereof with styrene. Copolymer, copolymer of butadiene and styrene,
Emulsions of various polymers, such as copolymers of butadiene and acrylonitrile, can be added.

The reason why coating film properties are stabilized by such pretreatment agents is not necessarily clear. It is speculated that the adsorption of the pretreatment agent on the surface of open deposits improves the wettability of the paint, lowers the film-forming temperature of the paint, makes it easier to form a film, and creates a stronger film, and that water-soluble This is thought to be due to the compaction effect of the sediment surface due to the soil temperature.

In the coating method of the present invention, first, the above-mentioned pretreatment agent is sprayed onto the surface of the field deposit at an amount of 0.5 to 6 kg/m ² , particularly preferably 2 to 4 kg/m ² . If the amount of spraying at this time is less than 0.5Kg/ ^m2 , it will not be possible to wet the surface of the field deposits sufficiently.
If it exceeds 6 kg/m ² , the water content in the surface layer becomes saturated, causing cracks to appear on the fluidized surface and the phenomenon of landslides.

The preferred method of dispersion is spraying, showering, etc., and care must be taken during spraying to ensure that the pretreatment agent does not run off the surface of the deposit and is sufficiently permeated.

After spraying the pretreatment agent in this way, a coating paint is applied at a rate of about 1 to 10 kg/m ² . As this paint, a wide range of conventionally known paints can be used as long as the solute becomes water-insoluble after drying, and it may be either a water emulsion type or an organic solvent type.
Particularly preferred coating paints are those that contain as a filler powder particles made of the same or similar material as the open deposits, and since this paint has good thixotropy, it does not penetrate into the interior of the deposits. permeation is suppressed, which is advantageous for the formation of a continuous film.

The coating film formed by the above coating is affected by variations in the condition and moisture content of the surface layer of open deposits, as well as variations in temperature, humidity, weather, etc. at the time of coating, depending on the function of the pretreatment agent. It exhibits uniform and continuous film properties without any cracks or tears even over time.

As described above, according to the present invention, it is possible to form a highly reliable, stable, and high-quality coating film on the surface of open deposits, thereby further enhancing the effects of waterproofing, dustproofing, and preventing oxidation by air of the deposits. be able to.

Next, examples of this invention will be described.

Example 1 A 0.3% by weight aqueous solution of propylene glycol was used as a pretreatment agent for coating. Apply this pretreatment agent to the floor area.
A spray of 2 kg/m ² was applied to the surface of an open pile of coal powder measuring 4000 m ² and 15 m high. The next day, 10 kg/m ² of coating paint having the composition shown below was applied and allowed to air dry. The deposit coated with this method did not disintegrate even after 6 months had passed, and during this period no coal dust generation, no runoff, and no change in water content were observed.

<Paint composition> 50% by weight water emulsion of 65/35 copolymer of butyl acrylate and styrene 100 parts by volume Ethyl cellosolve 2 parts by volume Water 20 parts by volume 5 mesh pass coal powder 1000 parts by volume Example 2 Methanol and glycerin A 10% by weight aqueous solution of a mixture of 1:1 by weight was used as a pretreatment agent for coating.
This pretreatment agent was sprayed onto the surface of an open pile of coal powder with a floor area of 3,600 m ² and a height of 11 m, at a rate of 4 kg/kg.
m ² sprayed. After about 10 hours, 8 kg/m ² of the same coating material as used in Example 1 was applied and allowed to air dry. The deposit coated with this method did not disintegrate even after 6 months had passed, and during this period no coal dust generation, no runoff, and no change in water content was observed.

Comparative Example: On the surface of an open pile of coal powder with a floor area of 3000 m ² and a height of 11 m, 10 kg/m ² of the same coating paint used in Example 1 was applied without applying a pretreatment agent, and the mixture was air-dried. I let it happen. Although the deposit coated with this method did not generate dust or wash away after 6 months, cracks appeared on the surface and the moisture content of the coal powder increased from the initial value of 9% by weight to 10.5% by weight. rose to.

Claims (1)

[Scope of Claims] 1. A pretreatment agent for coating field deposits containing one or more of monohydric alcohols, polyhydric alcohols, and derivatives thereof at a concentration of 0.05% by weight or more as an active ingredient. 2 Apply 0.5 to 6 kg/m of a coating pretreatment agent containing one or more of monohydric alcohols, polyhydric alcohols, and their derivatives as an active ingredient at a concentration of 0.05% by weight or more on the surface of open deposits. A method for covering open deposits, which comprises spraying the deposits at a rate of ² and then applying a coating paint containing a solute that becomes water-insoluble after drying.