JPH08283581A - Granular synthetic asphalt - Google Patents

Abstract

PURPOSE: To obtain a granular synthetic asphalt which can be easily produced, scarcely causes mutual fusion, and is easy to handle by granulating a synthetic asphalt and sticking a fine inorganic powder on the surface thereof. CONSTITUTION: A synthetic asphalt having a penetration of at least 40 is formed into granules of a mean diameter of 5-15mm. A fine powder of, e.g., a filler used for road paving and passing through a 0.074mm sieve is stuck in an amount of 1-10 pts. based on 100 pts. asphalt uniformly on the surface of the asphalt to give the granular synthetic asphalt which is substantially free from inorganic powder in the inside thereof.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a granular synthetic asphalt having an inorganic fine powder adhered to its surface. More specifically, by adhering calcium carbonate or other inorganic fine powder to the surface of granulated synthetic asphalt, the synthetic asphalt particles are less likely to fuse together even after long-term storage, and therefore granular particles that can be handled It concerns synthetic asphalt.

[0002]

2. Description of the Related Art Synthetic asphalt is composed of petroleum resin, oil, etc. and is a substance having properties similar to those of general asphalt produced by petroleum refining.
Synthetic asphalt is also called decolorizing asphalt, resin binder, etc., and is mainly used as road paving material in the same way as general asphalt, but it is used for the construction of color paved roads because it can be colored by adding pigments. Often. However, although synthetic asphalt is solid at low temperatures like general asphalt, it becomes semi-liquid at high temperatures in summer and adheres to the container containing it, making it difficult to handle as solid. Therefore, it is common to heat and handle in a liquid state, to store in a tank and to transport in a tank truck. However, in this method, the tank and the tank truck must be constantly heated, which is economically and safety inconvenient and is not suitable when a very small amount is used.

On the other hand, as a method for handling synthetic asphalt in a solid state, it is possible to use a method in which the synthetic asphalt is filled in a drum or a paper bag in a heat-melted state and then cooled and solidified, and this method uses synthetic asphalt. At that time, it is necessary to destroy the container, which is uneconomical, and the disposal method of the destroyed container becomes a problem. This problem also applies to general asphalt, and various methods for handling asphalt in granules have been proposed in order to solve this problem. It will be fused and the grain state cannot be maintained.

As a method for preventing the fusion of granular asphalt, Japanese Patent Application Laid-Open No. 2-5537 proposes a method of encapsulating asphalt. However, this method is very expensive because it encloses the asphalt in the form of fine particles in a capsule, and is inferior in economic efficiency. Also, as a fusion preventing method, in JP-A-6-73294, inorganic particles are dispersed in asphalt and then granulated,
Further, Japanese Patent Publication No. 52-28814 proposes a method of adhering an inorganic fine powder on the surface, and a method of mixing a radical polymerizable monomer with asphalt and then performing a radical reaction treatment. However, all of these methods have complicated asphalt manufacturing processes, and when this product is used for asphalt paving, etc., there is concern that components other than asphalt contained in this product may affect performance during use. .

Japanese Patent Publication No. 6-15046 proposes a method of coating a powdery or granular asphalt with a releasable organic compound or a powdery inorganic compound by a pulverizer. Whereas it is applied to hard asphalt of 0 or more and 20 or less, pavement asphalt generally has a penetration of 40 or more. As described above, the method of granulating general asphalt as well as synthetic asphalt has many problems, and has not been widely spread in general.

[0006]

An object of the present invention is to provide a product having the following performance. (1) It is a granular synthetic asphalt that is easy to handle. (2) During storage / transportation and during use, the particles do not fuse with each other and the particle state cannot be maintained. (3) Easy to manufacture. (4) Raw materials should be inexpensive. (5) Do not adversely affect the performance after use when put to practical use such as road pavement.

[0007]

As a result of intensive studies to solve the above problems, the present inventor adhered inorganic fine powder such as filler used for road pavement work to the surface of granulated synthetic asphalt. It was found that the seemingly simple method of performing the method is the cheapest method and has no problem in practical performance, and has completed the present invention. That is, the present invention relates to a granular synthetic asphalt characterized by having inorganic fine powder adhered to the surface of the granular synthetic asphalt.

The synthetic asphalt used as a raw material is preferably used for pavement work with a penetration of 40 or more, and it is desirable that the grain size be 5 to 15 mm in average diameter, but the grain shape is arbitrary. Is. The particle size of the inorganic fine powder adhered to the surface of the particles is preferably that which passes through a 0.074 mm sieve. If the particle size is coarser than this, the particles do not adhere well to the surface of the synthetic asphalt and fall off due to its own weight, and the amount of fusion between the synthetic asphalt particles increases during storage or transportation, which may cause a practical problem. Also, the amount of inorganic fine powder to be attached to the surface of synthetic asphalt is 1
About 1 to 100 parts of inorganic fine powder is desirable with respect to 00 parts. If the amount of the inorganic fine powder is less than this range, the amount of fusion of the synthetic asphalt particles to each other increases, and if it is more than this range, a problem may occur during pavement work. Since the inorganic fine powder may be attached to the surface of the synthetic asphalt, it is not necessary to include it in the synthetic asphalt itself, and in order to attach this to the surface, it is sufficient without using an adhesive, A small amount of various adhesives may be used.

Japanese Unexamined Patent Publication (Kokai) No. 6-73294 describes a granular asphalt obtained by adhering inorganic fine powder to granular asphalt as in the present invention. However, in this publication, since this method has a small effect of preventing fusion between grains,
It is described that if these are filled in a paper bag or the like and piled up in a large amount, a load is applied to the particles, so that fusion of the particles cannot be prevented. The present inventor tried the present method in a straight asphalt, a semi-blown asphalt, an elastomer-modified asphalt and a high-viscosity binder as in this publication,
Although it was found that the performance of maintaining granularity was improved, it was confirmed that the performance was low and there was a problem in practical use.

However, the present inventor has found that depending on the type of asphalt to be used and the size of its asphalt, its performance is remarkably improved and it can be sufficiently put to practical use. That is, using synthetic asphalt as asphalt,
In addition, if the average diameter of the asphalt particles is set to 5 mm to 15 mm, it becomes possible to maintain the particles for a long time only by making the asphalt particles granular and attaching the inorganic fine powder to the surface, and there is no practical problem. That is, it has been found that even if the asphalt granulated by the method of the present invention is filled in a drum can, the granular state can be maintained even if the asphalt is filled in a paper bag and stacked in several stages. This is because synthetic asphalt has a high softening point, is less likely to lose its shape even at a relatively high temperature, and can maintain the state of particles, so that the contact area between particles is small, and therefore particles are less likely to fuse together. .
Further, if the asphalt particles are too large, the particles are deformed due to the weight of the particles to increase the contact area between the particles, and if the particles are too small, the particles are densely packed, so the contact area also increases and Fusing becomes easy.

The inorganic fine powder used in the present invention is preferably a filler generally used for road pavement, if possible, and is a finely powdered calcium carbonate that passes through a 0.074 mm sieve. Igneous rock powder, cement, fly ash, recovered dust and slaked lime can be used. Since all of these fillers are used for ordinary road pavement work, when the present invention product is used for road pavement applications, there is no practical problem and it is included in the present invention product during pavement work. This is a great advantage of the present invention in that the total material cost of road pavement work does not change at all theoretically because the amount of filler used can be reduced.

Although not normally used as a filler, gypsum, calcined gypsum, etc. can be used as the inorganic fine powder for the present invention without any problem. Furthermore, FC
Fine powdered inorganic pigments such as C waste catalyst (fine powdered catalyst used in a fluid catalytic cracking device in petroleum refining) and rouge can also be used. The former has many merits both economically and in terms of environmental conservation, since it is possible to use what should be discarded. Regarding the latter, since the synthetic asphalt is mainly used for color pavement, even if the pigment is used for the purpose of the present invention, there is no problem in use.

[0013]

EXAMPLES The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. (Example 1) About 100 g of synthetic asphalt was made into granules with an average diameter of about 8 mm (average volume 0.27 cm ³ ). Almost the same amount of finely powdered calcium carbonate as the synthetic asphalt was placed in a glass container, the granular synthetic asphalt was added thereto, and the mixture was well stirred with a spatula. This was sieved to remove excess inorganic fine powder to obtain granular synthetic asphalt. (Examples 2 to 6) The inorganic fine powder of Example 1 was mixed with gypsum (Example 2), calcined gypsum (Example 3), cement (Example 4),
The FCC waste catalyst (Example 5) or slaked lime (Example 6) was changed to obtain a granular synthetic asphalt by the same method as in Example 1.

(Comparative Examples 1 to 4) Instead of the synthetic asphalt of Example 1, straight asphalt (Comparative Example 1),
The semi-blown asphalt (Comparative Example 2), the elastomer-modified asphalt (Comparative Example 3) or the high-viscosity binder (Comparative Example 4) was used to obtain granular asphalt in the same manner as in Example 1. (Comparative Example 5) A synthetic asphalt having a mean diameter of about 8 mm was formed into a granular synthetic asphalt in which the inorganic fine powder was not attached to the surface.

(Test Example 1) 100 ml of each of the thus obtained granular synthetic asphalt or granular asphalt in an apparent volume was placed in a glass cylindrical container having a diameter of 4 cm and kept in air at 40 ° C. for 6 hours. Left unattended. After leaving it to stand, cool it to room temperature and remove the contents.
The weight of fused synthetic asphalt or granular asphalt was measured. The results are shown in Table 1. (Test Example 2) 20 g of the granular synthetic asphalt obtained in Example 1 and the granular asphalt obtained in Comparative Example 4 were placed in a glass cylindrical container having a diameter of 5.5 cm, and 2.2 kg from the top. It was left at room temperature for 1 week under load. After standing, the contents were taken out and the presence or absence of granular synthetic asphalt or granular asphalt was confirmed. The results are also shown in Table 1.

When asphalt is stored as granules,
Summer storage temperatures can reach 40 ° C. Test example 1
The result shows that the product of the present invention has sufficient practical performance even under such a condition. Further, when the granular asphalt is stored, it is expected that the granular asphalt is placed in a drum or filled in a paper bag and then stacked, and a considerable load is expected to be applied to the asphalt. The load of 2.2 kg applied to the sample in Test Example 2 corresponds to the load received at the bottom of the granular asphalt filled in the drum can.
Further, when the paper bag is filled with a normal paper bag containing 25 kg, this corresponds to the load received by the lowermost part of the paper bag stacked in nine stages. Even in such a situation, the result of Test Example 2 shows that the product of the present invention has sufficient practical performance.

[0017]

[Table 1]

[0018]

【The invention's effect】

(1) When asphalt is stored as granules, the storage temperature in summer may reach 40 ° C. Furthermore, it is expected that they will be placed in drums or filled in paper bags and then stacked, and it is expected that a considerable load will be applied to the lower asphalt. The product of the present invention has little fusion between grains even under such a condition, can maintain the grain state, and has sufficient performance for handling as grains even in practical use. (2) The product of the present invention can be manufactured simply by granulating the synthetic asphalt and then simply sprinkling the surface with the inorganic fine powder and stirring. (3) As the inorganic fine powder attached to the synthetic asphalt, inexpensive one such as calcium carbonate can be used. In addition, the amount of the inorganic fine powder used can save the filler used during road construction, which is economical. (4) Of the materials used in the present invention, not only those generally used for ordinary road pavement, but also other materials are used when the present invention product using this as a material is used for road pavement. , It is unlikely that it will adversely affect the performance of the finished paved road. Also,
The existing method can be used as it is for road pavement design, and the reliability of the design is improved.

Claims (2)

[Claims] 1. A synthetic asphalt having a penetration of 40 or more is formed into particles having an average diameter of 5 to 15 mm, and 0.074 is formed on the surface thereof.
mm Asphalt 100 made of fine inorganic powder that passes through a sieve
Particulate synthetic asphalt, characterized in that it is uniformly adhered to 1 to 100 parts with respect to parts, and that the inorganic fine powder is not substantially contained therein. 2. The inorganic fine powder is calcium carbonate, igneous rock powder, cement, fly ash, recovered dust, slaked lime,
2. The granular synthetic asphalt according to claim 1, which is any one kind or a mixture of two or more kinds selected from fine powder inorganic pigments such as gypsum, calcined gypsum, FCC waste catalyst and rouge.