JPS62131084A - Moisture content increase inhibitor for open piled coal - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to an agent for suppressing an increase in moisture content of open coal.・ (Conventional technology) In recent years, energy conservation and resource conservation have been called for in the wake of the oil crisis, and at the same time, as coal has regained its status as an energy source, the amount of coal used has also been gradually increasing. .

Along with this, various issues related to coal storage have also come into focus. For example, various countermeasures are being considered, such as preventing coal dust from scattering, preventing heat generation, preventing deterioration, and preventing rainwater from penetrating.

However, no serious measures have yet been taken to prevent rainwater from penetrating into open piled coal.The increase in water content due to rainwater seepage into open piled coal causes excess energy to be consumed due to moisture during combustion, resulting in economical Not only does this result in large losses, but in the case of coking coal, it also has various negative effects on the coke manufacturing process.Therefore, even suppressing the increase in moisture content of coal by 1% due to rainwater can generate large profits. Become.

In the past, various proposals have been made regarding means for suppressing the increase in moisture content of coal. For example, JP-A-55-43
No. 133, No. 59-82203, No. 58-11727
No. 0, No. 58-117271, No. 59-89391, No. 59-147089, No. 59-174695,
No. 60-40305, No. 60-40306, etc.

All of the methods proposed in the past are practical methods and can be implemented immediately, however, they have some drawbacks.

l) In order to put the resin film alone into practical use, it is necessary to use a reinforcing agent that is the same as or similar to that of open deposits or made of an organic or inorganic material.

2) When using the resin film alone, a pre-process is required, such as mechanically increasing the density of the surface layer of the open coal pile under pressure and then forming the resin film.

3) When using the resin film alone without prior treatment,
In order to increase the adhesion to coal, cationic resins and resin emulsions with a small amount of emulsifier (or no emulsifier) are used, but they have weak waterproofing and water repellency, and are not effective in suppressing the increase in moisture caused by rainwater.

Therefore, when performing rainwater infiltration prevention processing on open pile coal piles without pre-treatment with a resin film alone, in practice:
A two-part spraying method is used in which a resin emulsion is first sprayed as a hardening agent, then dried, and then a resin emulsion made of hydrophobic monomer is sprayed as a penetration preventer to form a resin film. There are many things.

However, although such a two-part method can temporarily prevent rainwater penetration, it is necessary to dry the first one-liquid method and then spray the second resin emulsion, and at least continuously. Unless the day is expected to be sunny for three to four days, the resin emulsion cannot be sprayed, which poses a problem in terms of work.

It is difficult to carry out this process especially during the rainy season when waterproofing is required.

In addition, in JP-A No. 58-117271, the blending ratio of solute and filler, which are film-forming components in the paint, was specified, and a water-repellent agent such as silicone, paraffin, and low-molecular polyethylene was added. It is disclosed that ta aqueous properties and i#W properties are imparted to film formation. However, in this case, since a fairly large amount of filler is used, the film forming properties are quite poor, a continuous film cannot be obtained, and there are some difficulties in preparing the paint, such as difficulty in uniformly blending.

(Problems to be Solved by the Invention) An object of the present invention is to provide an excellent inhibitor of moisture content increase in open coal that is inexpensive and has good workability under these circumstances.

(Means for Solving the Problems) In order to eliminate the drawbacks of the above-mentioned conventional methods, the present inventors have made intensive studies and found that after drying water having a glass transition temperature in the range of 5 to -50°C, 3 to 1 part of the water repellent agent per 100 parts by weight of the solute in the resin emulsion that forms the insoluble film.
It was discovered that the above drawbacks could be improved by using a resin liquid containing 5 parts by weight, and the present invention was successfully developed.

Here, the gist of the present invention is that 5℃~=50℃
An increase in the moisture content of open pile coal, characterized in that it contains 3 to 15 parts by weight of a water repellent agent per 100 parts by weight of a solute in a resin emulsion that forms a water-insoluble film after drying and has a glass transition temperature in the range of It is an inhibitor.

(Function) The main chain monomers constituting the dried water-insoluble resin Emulsilon used in the present invention include acrylic acid esters such as methyl acrylate, ethyl acrylate, butyl acrylate, and 2-ethylhexyl acrylate; methyl methacrylate, ethyl methacrylate, Examples include methacrylic acid esters such as butyl methacrylate and 2-ethylhexyl methacrylate; acrylonitrile; methacrylonitrile; vinyl acetate; styrene: ethylene; butadiene; vinyl chloride: vinylidene chloride. others,
Acrylic acid, methacrylic acid, glycidyl methacrylate, acrylamide, N-methylol acrylamide,
A polymerizable functional monomer such as 2-hydroxyethyl methacrylate may be used in combination.The copolymerization ratio of these monomers is such that the glass transition temperature of the resulting copolymer resin is as follows (
According to the formula 1), the temperature is appropriately selected within the range of 5 to -50°C, preferably θ to -30°C.

7g+273 Tg++273 7gx+2
73ll ...+□ ...(11 formula % formula % Here, Tg is the transition temperature expressed in °C, Tg+, Tg,
...Tg++ is the Tg of the monopolymer of each composition monomer,
-1, enemy2...represents the weight fraction of composition 1.2...n.

When this glass transition temperature T exceeds 5°C, the rubber elasticity of the film formed on the surface layer of the open coal pile is poor, and therefore it cannot absorb the strain caused by the sinking of the coal itself or the strain caused by mechanical vibration. First, the resin film is more likely to crack. Furthermore, the film formation properties at low temperatures (winter) are poor, and film-forming aids must be used in combination, and as a result,
This will lead to secondary pollution such as bad odors and a decrease in drying performance.

On the other hand, when the glass transition temperature Tg is less than -50°C, the film formation properties are good at low temperatures, but at high temperatures (summer)
There is a drawback that the strength of the film decreases.

In addition, since the glass transition temperature exhibits additivity as described above, a desired value can be obtained by appropriately changing the type and amount of each compositional monomer.

Examples of the T8 aqueous properties imparting agent include wax-based, wax/aluminum salt-based, wax/zirconium salt-based, quaternary pyridinium-based, fatty acid amide resin-based, silicone-based, fluororesin-based, low molecular weight polyethylene, fatty acid ester, etc. There is.

These are appropriately used in emulsion form as emulsifiers, etc., but silicone-based and fluororesin-based ones have good water repellency, but are not economical and suitable for practical use, quaternary pyridinium-based and fatty acid amide. Resin-based emulsions, low-molecular-weight polyethylene, and fatty acid esters have low TA-water effects, and it is preferable to use wax-based, wax-aluminum salt-based, and wax-zirconium salt-based emulsions from the viewpoint of to-aqueous properties and economic efficiency.

This water repellency imparting agent is used by being blended with the resin emulsion and the open coal pile immediately before being sprayed, but it may also be blended during synthesis of the resin emulsion.

In the resin emulsion used here, the water absorbency of the formed resin film varies depending on the type and amount of the emulsifier used in the synthesis stage, so the water repellent should be used at least per 100 parts by weight of the solute in the resin emulsion. , 3 parts by weight or more is required; if it is less than this, the water repellency is extremely poor and it is impossible to prevent rainwater from penetrating. On the other hand, if the amount exceeds 15 parts by weight, the strength of the resin film decreases. therefore,
3 to 1 per 100 parts by weight of solute in the resin emulsion
It is necessary to use 5 parts by weight, preferably 5 to 12 parts by weight of the water-imparting agent.

In addition, as is already known in the art, in water emulsion systems, especially membrane-forming aids (e.g., nibutyl cellosolve), thickeners (e.g., methyl cellulose), t1
2M (N: (!Tyl alcohol) etc. may be added as appropriate.

By the way, in order to apply the moisture content increase inhibitor of the present invention to open piled coal, a spray liquid adjusted to a solid content of 5 to 10% by weight is usually applied per 1I12 of the surface of the piled coal pile as a solid content. 50 to 300g, preferably 150 to 300g, is uniformly spread over the entire surface of the coal pile using a spreader. The moisture content increase inhibitor of the present invention exhibits a sufficient effect when sprayed once, but there is no hindrance to spraying it several times.

Any of the following scattering methods may be used.

1) After forming a coal pile, spread it on the surface layer.

2) When a coal pile is formed, the coal being transported, which will become the surface layer of the coal pile, is sprinkled on a belt conveyor.

3) When the coal pile is formed, all the coal being transferred is spread on the belt conveyor.

When the moisture content increase inhibitor of the present invention is sprayed on open coal piles, a flexible film with good water repellency is formed on the surface of the coal piles. Therefore, the flexible resin film absorbs the strain caused by the sinking of the piled coal itself, and there are fewer cracks compared to hard resins that emphasize strength.Moreover, the TA water effect prevents the penetration of rainwater, etc., and it also provides 18 water properties. By using the agent in combination, only one spraying is required, so compared to the method of spraying twice, the film has moisture permeability, facilitates the evaporation of internal moisture, and suppresses an increase in the moisture content of the coal.

Next, the present invention will be explained in more detail by giving examples.

The 5th sieve in the history of forks (concrete aggregate standard sieve JIS size 5, mesh opening 4.760mm, wire diameter 1.290o+m)
) was piled up in a conical shape with a diameter of 30 cm on a flat plate inclined at 5 degrees (one that does not absorb water), and added with the resin emulsion shown in Table 1 and ta aqueous. After the agent (paraffin wax with a melting point of 135 or less) was mixed and prepared, it was uniformly dispersed.

Is the ta aqueous agent 50%? The amount of spraying as a water emulsion emulsified and dispersed at Wi degree is 3 j! /mt equivalent amount.

After air-drying at room temperature for 3 days, the film was exposed to artificial rain with a rainfall intensity of 50 mm/hr for 1 hour, and then the increase in water content and the state of film formation were examined. The results are summarized in Table 2, and the moisture content was determined from equation (2).

Here, -1: weight at sampling, W: 110°C
Indicates the weight at constant weight.

Table 1 Note 3): *Outside the scope of the present invention Table 2 Test floors 1 to 4 had good evaporation of internal moisture without penetration of rainwater due to rainfall. In Test N15, which is a comparative example, the water content was as high as 9.0% because the amount of t8 liquid was small. Also,
In Test No. 6, since there was a large amount of 1a water solution, the water content was low and good, but there was a problem that cracks occurred in the film formation.

In the 1m7.8 tests, the glass transition temperature was outside the limited value, and cracks or deformation occurred in all cases.

In addition, according to JP-A-58-117271, the resin composition ratio is 50 consisting of EA:BA:8N=75:20:5.
% emulsion as a solute, 2000 parts of coal powder of 5 mesh passes and 20 parts of 50% water emulgitan of paraffin wax with melting point below 135 were mixed with it.
It was not possible to spray with a spray gun or the like, and a uniform continuous coating could not be obtained even if sprayed with force.

Resin composition ElhBA: A in a coal pile (Finchit Canadian Coal) with a fork scarf width of 30 cm and a length of 110 cm and a total amount of 170,001 cm.
The solute concentration of the resin emulsion consisting of N = 75:20:5 was adjusted to 9%, and the melting point was 13 as a water repellency imparting agent.
5. Melt the paraffin wax in the resin emulsion.
A spraying solution ■ containing 11 parts by weight per part by weight of O and a spraying solution ■ containing 1 part by weight in the same manner were prepared, and an amount equivalent to 31/la'' per surface area of the open coal pile was sprayed on each half of the coal pile for comparison. A test was conducted.The ta aqueous imparting agent used was water emulsion silane emulsified and dispersed to a concentration of 50%.

Claims (1)

[Claims] Solute 100 of a resin emulsion forming a water-insoluble film after drying having a glass transition temperature in the range of 5°C to -50°C
An agent for suppressing an increase in water content of piled coal, characterized in that it contains 3 to 15 parts by weight of a water repellency imparting agent.