JPS61281185A - Production of snow melting material for preventing scattering - Google Patents

Abstract

PURPOSE:To obtain a snow melting material for preventing scattering, which will neither scatter nor disappear uselessly during application, and not settle in snow, obtained by adding black pigment and a binder solution to raw material powder having a specific particle size constitution, granulating the blend and drying it. CONSTITUTION:Raw material powder (e.g., calcium carbonate) having a particle size constitution consisting approximately of 30wt% particles with <15mm particle size, 10wt% particles with 0.15-0.35 particle size, 40wt% particles with 0.35-0.84mm particle size, and 20wt% particle with >=0.84mm particle size is blended with black pigment (e.g., carbon black, etc.) and a binder solution (e.g., pulp waste liquor, etc., granulated and dried, to give the aimed snow melting material preventing scattering. EFFECT:Amounts of pigment and a binder solution used are reduced, time for granulation and drying are shortened and electric power cost and fuel cost are reduced.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is a snow-melting material that is used in snowy areas to spread on snow-covered surfaces to promote snow melting. The present invention relates to a method for producing a snow-melting material that prevents snow from falling and from settling during snowfall.

[Conventional technology]

Conventionally, powdered and granular snow melting materials are known. The former, ie, powdery snow melting materials, include fly ash, calcium carbonate with carbon blank, etc., and the latter, ie, granular snow melting materials, include, for example, mixing calcium carbonate with carbon black and making it into granules using an appropriate binder liquid. It is something that becomes.

[Problem that the invention seeks to solve]

Most of the powdered snow melting materials mentioned above have particles with a diameter of less than 0.15 m (approximately 70%) and are blown away by even the slightest wind when being spread, making it impossible to accurately spread them onto the snow-covered surface to be melted. In addition, carbon blanks, which have a particularly low specific gravity, can be blown away by the wind even after being spread, making it difficult to effectively collect sunlight on the snow surface. The drawback was that it couldn't be done.

The above-mentioned granular snow-melting material eliminates the above-mentioned drawbacks of the powdery snow-melting material. However, conventional granular snow melting materials have a diameter of O.15
Calcium carbonate, etc., of which about 70% of particles are less than mm in size, is used as a raw material powder, and a black pigment and a binder liquid are added to it to granulate it. Because the particle size of the raw material powder is small, the total surface area of the particles is small. becomes large, and therefore requires a large amount of the black pigment and binder liquid, and
The granulation and drying times also become longer, which has the drawback of increasing material costs, electricity and fuel costs, and increasing costs.

In addition, as long as this granular snow melting material is granulated by transferring the raw material powder to it using a transfer type granulator while spraying a binder liquid, the particle size of this granular snow melting material is usually 1 to 4 fins. Because most of them are relatively large, they tend to settle during the snowfall and remain on the snow surface and cannot effectively collect sunlight, or even if the amount of spray is the same,
Compared to powdered snow melting materials, the total surface area is smaller and therefore the light gathering rate is lower, so there is the problem that more than twice the amount of powdered snow melting materials is required to achieve the same level of snow melting. Ta.

An object of the present invention is to provide an anti-snow melting material that solves these problems.

[Means for solving problems]

In the present invention, the particle size structure is approximately less than 0.15 30% 0.15
Crane or more 0.35m + less than 10% 0.35n
It is characterized by granulating and drying the raw material powder, which is 40% for those less than 0.84 tm and 20% for those 0.84 t or more.

[Effect]

In the present invention, most of the raw material powder, i.e. 70%, is 0.151
Unlike conventional raw material powders, in which 70% of the powder is smaller than 0.15 mm, the total surface area is smaller due to the larger particle size, so black pigment And a small amount of binder liquid is sufficient,
And along with this, granulation and drying time can be shortened,
This means that material costs, electricity and fuel costs can be saved, and products can be manufactured at lower costs.

〔Example〕

Calcium carbonate as a raw material powder is pulverized using a pulverizer 1 so that it has the following particle size structure.

Less than 0.15 cranes 30% 0.15
More than 0.35 cranes and less than 0.35 cranes 10% More than 0.35 cranes and less than 0.84 40% More than 0.84 cranes 20% This calcium carbonate 3.5
00ksr/h was fed to the kneader 2, and at the same time, 25kg/h of carbon black as a black pigment and 210kg/h of pulp waste liquid as a binder liquid (optimally 6 to 7% by weight of the raw material powder) were added. , knead these well.

Due to this crosstalk, the calcium carbonate and carbon blank are mixed uniformly, while the calcium carbonate particles are presumed to cause a small amount of carbon black to adhere to each surface in the form of a thin film due to the valve waste liquid.

The kneaded material is then sent to the crusher 3. This crusher 3 crushes the kneaded lumps generated during the above-mentioned mixing.

This completes the pre-granulation stage treatment, then feeds it to the transfer type granulator 4, and at the same time sprays 105 kg/h of pulp waste liquid as a binder liquid (optimally 3 to 4% by weight of the raw material powder). It was added and granulated. At this time, the rotational speed of the granulator 4 was set to 14 RPM, and the inclination angle was set to 55°.

After granulating with the granulator 4, it is placed in a rotary dryer 5 and dried to a moisture content of about 0.2 to 1.0%. In addition to the drying function, this dryer 5 breaks down the lump-like portions where particles adhere to each other and sorts the particles.

The particle size composition of the finished product was as follows.

Less than 0.15m 0.6%0.15
Crane or more 0.35 crane less than 20.6% 0.35m
More than 0.84n 47.1%0.84mm
Those smaller than 1.19 meters: 11.0% Those above 1.19 meters: 20.7% Looking at this particle size composition, there are almost no particles smaller than 0.15 meters.
It is presumed that it was attached to the surface of particles with a diameter of 0.15 m or more.

In addition to the valve waste liquid, molasses, alcohol waste liquid, etc. can be used as the binder liquid. In addition, black pigment is
In addition to carbon black, black Bengara (1"5203), fly ash, etc. may also be used.

After grading with a rotary dryer 5, the particles were passed through a 4 m sieve 6 to further improve accuracy, but there were almost no particles with a particle size of 4 days or more.

In order to obtain the same level of black coloring as the product according to the present invention using the conventional method using 3,500 kg/h of calcium carbonate, in which 70% of the particles have a particle size of less than 0.15 tm, as a raw material powder, the present invention is required. 35 to 70 kg/h of carbon black is required, far exceeding the 25 kg/h in the case of the invention, and in this case, the binder liquid also requires 350 to 380 kg/h, which exceeds 315 kg/h in the case of the present invention. This was confirmed by experiment.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, the raw material powder has the following particle size configuration, that is, approximately less than 0.15 mm: 30% 0.1
5m or more but less than 0.35m 10% 0.35m
By using 40% of 0.84n or more and 20% of 0.84n or more, the amount of pigment used in carbon blanks, binder liquid such as valve waste liquid, etc. can be reduced from the conventional 70% to 0.15mm. Compared to the case where raw material powder is used, which accounts for less than 1,000 particles, it is possible to reduce electricity and fuel costs by shortening the granulation and drying time.

Moreover, as shown in the examples, the particle size structure is 0.1
Reduce the proportion of those less than 5mm and those of 1.19 m or more, and approximately 60 of those of 0.35 m or more and less than 1.19 m.
%, and it eliminates the various drawbacks of conventional powdered and granular snow melting materials,
A sufficient snow melting effect can be expected.

[Brief explanation of drawings]

The drawings are flowcharts illustrating embodiments of the invention. ■...Crusher, 2...Kneader, 3...
... Crushing machine, 4 ... Granulator, 5 ...
・Rotary dryer, 6...Sieve.

Claims (1)

[Scope of Claims] 1. 30% particles with a particle size structure of approximately less than 0.15 mm 10% particles with a particle size structure of 0.15 mm or more and less than 0.35 mm 0.3
5mm or more and less than 0.84mm 40% 0.84mm
Black pigment and binder liquid are added to the raw material powder which is 20% of the above,
A method for producing a snow-melting material that is characterized by granulation and drying.