JP2003247208A - Method of collecting aggregate from waste asphalt mixture - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable the treatment a total amount of waste asphalt mixture by increasing the rate of recycling it as a recycled asphalt material through separation and refining by components and utilizing aggregate components as normal aggregates in other applications in order to solve the problems on the waste asphalt mixture most of which is road materials to be recycled as a recycled asphalt mixture and all of which is, however, not recycled, namely, the rate of recycling is limited to 75% even in the latest technology, that the storage amount of the waste asphalt mixture tends to increase, asphalt suffers deterioration and some is impossible to recycle. <P>SOLUTION: This method comprises separating aggregate components and asphalt components in the waste asphalt mixture while causing the collision of particles of the asphalt mixture coated with the asphalt with one another without changing the shapes and particle sizes of aggregates and then collecting high-grade aggregates and high-content asphalt components using a gravity concentrating machine. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention separates an asphalt component and an aggregate component of gravel and sand from a waste asphalt or a waste asphalt mixture collected from an asphalt pavement, an asphalt material for buildings, etc. as industrial waste. -It relates to a method of refining and reusing each component as a raw material of the same manufacturing plant or a raw material for other uses.

[0002]

2. Description of the Related Art As shown in FIG. 1, there are a mechanical crushing method and a thermal crushing method as a method for producing a recycled asphalt aggregate from a waste asphalt mixture of the prior art. According to Fig. 1, 40 mm or less of the waste asphalt mixture is used as recycled roadbed material, and 40 mm or more is mechanically crushed again or crushed by heat treatment, and recycled asphalt aggregate with about 6 to 8% asphalt attached. Are manufactured.

The method for producing a recycled asphalt mixture is, for example, after producing a recycled asphalt aggregate by a mechanical crushing method, as shown in the crushing equipment surrounded by the one-dot chain line in FIG. The waste material asphalt mixture of about 1,000 mm or less is crushed to a particle size of 40 mm or less, and the particle size is 40 mm to 13 mm and 13 mm by a sieving machine.
The particles are classified into the following two types, and particles having a diameter of 13 mm or less are used as a raw material aggregate for recycled asphalt. The raw material aggregate for recycled asphalt is heated and adjusted in the recycled raw material aggregate heating equipment surrounded by the one-dot chain line, and then used for the regeneration of asphalt aggregate and softener and stone powder produced from the general-purpose asphalt plant used together. It is manufactured by mixing additives.
Therefore, the aggregate used in recycled asphalt plant is
Aggregates in general-purpose aggregate and waste asphalt mixture are used after adjusting the mixing amount according to the quality of the waste asphalt mixture. The waste wood asphalt mixture is originally a product manufactured from a general-purpose asphalt plant, but when it is collected as a waste wood asphalt mixture, its quality remarkably differs due to deterioration of the asphalt. or,
In many cases, dirt, wood chips, and existing roadbed materials are also mixed.

FIG. 3 shows a method for producing a recycled asphalt mixture by the method for producing a heat-type recycled asphalt aggregate for a thermal crushing system. The recovered waste asphalt mixture is crushed and sieved to a particle size of 100 mm or more and below. The particle size of 40 mm or less is directly supplied to the dryer for recycled asphalt aggregate. In addition, the particle size of 40 mm or more is discontinuously heat-treated by a heating device, crushed to a particle size of 40 mm or less, and then supplied to a dryer for recycled asphalt aggregate together with a waste material asphalt mixture having a particle size of 40 mm or less. A recycled asphalt mixture is manufactured through a flow similar to the method for manufacturing recycled asphalt of aggregate for recycled asphalt of mechanical crushing method at room temperature.

The mechanical crushing method for producing recycled asphalt aggregate is a continuous method, whereas the heating method is a discontinuous method. However, since the asphalt content adheres to the surface of the existing aggregate for recycled asphalt, quality stability becomes a problem. Therefore, the “Recycled Pavement Technology Guideline for Plants” sets the standard, and the usage of reuse rate is limited. Therefore, it is not possible to reuse all of the collected waste wood asphalt, and there is a tendency for the amount stored in the intermediate treatment plant to increase.

[0006]

DISCLOSURE OF INVENTION Problems to be Solved by the Invention The present invention provides a method for producing aggregate for recycled asphalt by the existing method, which has a limited utilization rate and cannot use the aggregate for other purposes. Not only improves the quality of aggregate components by removing asphalt components from the mixture and increases the utilization rate as aggregate for recycled asphalt, but also as aggregate for general-purpose asphalt by making it to the same level as components of general-purpose aggregate. Also make it reusable.

Further, it is a method of manufacturing an aggregate having a quality that can be reused as a general aggregate. In addition, the waste asphalt mixture having a high asphalt content can be reused as a raw material of the asphalt for recycled asphalt by forming a silt of 0.5 mm or less. In addition, by making full use of the characteristics of the high-content asphalt, it is possible to reuse the entire amount of the waste asphalt mixture.

Therefore, the production of a recycled asphalt mixture using the conventional aggregate for recycled asphalt requires a dedicated regeneration mixing facility, but when high quality recycled aggregate is used for the recycled asphalt mixture, the existing general-purpose asphalt is used. The plant can be used to share a general-purpose asphalt mixture production line. In addition, existing recycled aggregate containing asphalt components has a property that it solidifies again during deposition and storage, and reprocessing is required at the time of use. It can be handled as a material. Also, in the recycled aggregate for asphalt containing various kinds of asphalt components, there is a limit to the type of asphalt mixture to be mixed, but since high quality recycled aggregate can be handled as normal aggregate, it is becoming more and more used. It can be used for certain high-performance pavement materials and other special pavement materials, leading to expansion of the range of applications for recycled products.

In the production of a recycled asphalt mixture by using the existing recycled aggregate for asphalt, regardless of the mixing ratio and the room temperature / heating at the time of mixing, the quality is influenced by the atmospheric temperature change due to its nature, and particularly in the cold season manufacturing. However, the quality of the aggregate is limited, and the production period is limited, and the production is suspended during the winter period. However, high quality recycled aggregate can be produced for the entire period.

Therefore, the crushed and sieved 13 m of the present invention
Separation and purification of a waste asphalt mixture of m or less into an asphalt component and an aggregate component can be performed, for example, by using an aggregate for concrete, or as an asphalt recycled additive, an asphalt paving material, a waterproofing agent, or a crack filler. As a result, the entire amount of waste asphalt mixture will be completely used as recycled material.

[0011]

[Means for Solving the Problems] The method of reusing the aggregate by the existing technology is based on the idea of using the asphalt component without separating and refining and the lack of a technical means for separating and refining. Therefore, the present invention is a method for separating the asphalt component in the waste asphalt mixture, as a means for recovering the aggregate component without changing the shape and particle size of the aggregate, by removing the asphalt component while colliding the particles with each other. It is an invention of a method for recovering high-grade aggregate and high-content asphalt component by a specific gravity sorter after separation.

A waste asphalt mixture, for example, having a particle size of 13
When crushed to a size of less than mm by a general-purpose crusher, the crushed surface state of most of the particles has a shape in which asphalt is fixed to the particles. The bond strength between the asphalt and the aggregate is a physical surface adhesion unlike the scientific bond, and is in a state of coating on the surface of the aggregate. Further, according to the "Plant Reclaimed Pavement Technology Guideline" set by the Japan Road Association, which is the standard used as a pavement asphalt mixture, stability, flexibility, slip resistance, durability, and workability are
The requirements for aggregates are specific gravity and water absorption, abrasion loss, stability, shape, particle size distribution, and harmful substance content, and the adhesive strength between asphalt and aggregates is only shown as an indirect result. However, the separation of the basically hydrophilic aggregate and the oil-based asphalt can be performed by repeating collision of particles coated with the asphalt component with each other.

Table 1 shows the types and conditions of standard general-purpose asphalt mixtures. Minimum asphalt content 3.5
%, The maximum asphalt content is 9.5%, but the asphalt content of a general-purpose asphalt mixture is as a mixture type, for example, in the case of a snowy region, there are many asphalt mixtures of is there.

Table 2 shows an example of the asphalt content of the regenerated asphalt mixture. Basically, the asphalt content is adjusted to the same asphalt mixture similar to the general-purpose asphalt mixture.

[0015]

[0016]

In solving the problem, the separation / purification test is performed according to the separation / purification flow shown in FIG. A machine that separates asphalt and aggregate components while colliding particles with each other. However, the specific gravity sorter performs sorting in a specific gravity zone having a relatively close specific gravity, but it is possible to sort in any specific gravity zone,
It is possible to arbitrarily obtain the target quality value of the aggregate.

Table 3 shows the product number names shown in FIG.
Although the material balance of the asphalt content rate for 11 is shown, the asphalt content of the sample 11-0.5 mm regenerated asphalt mixture is a high value.

[0019]

The contents of FIG. 4 and Table 3 will be further described. Figure 4
The -40 mm particle waste asphalt mixture is crushed to -13 mm by a crusher, and -5 mm particles are further classified into a waste asphalt mixture of 5 to 0.5 mm particles and -0.5 mm particles by a sieving machine. The asphalt content is 7.58%, and it is shown that the asphalt component contained in the -0.5 mm particles is not so large in this state. After separating the asphalt component adhered to the particles and the aggregate by a fine pulverizer, +
When classified into 0.5 mm particles and −0.5 mm particles, the asphalt content of the product number −0.5 mm particles is 16.6.
It is 1%, and it has been proved that a large amount of asphalt component is contained in the fine particles by peeling the particles while colliding them. In addition, +0.5 mm particles are classified into 3 types of light specific gravity, intermediate specific gravity, and (10) by a specific gravity sorter.
When the particles with high specific gravity are selected, the asphalt content of each product number, product number, and product number (10) in Table 3 is as high as that of light specific gravity particles, but lower than the content ratio before selection of product number specific gravity of 3.89. It turned out to show a value. Also, the product number (11) -0.5 mm particles could be recovered as an asphalt mixture of a high asphalt content of 81.00%. According to this test result, it is shown that the -0.5 mm particles obtained by the method of colliding the waste asphalt mixture with the particles can be used as a material having a high asphalt content other than the raw material of the regenerated asphalt mixture,
In addition, + 0.5mm particles are also included as low asphalt content-
It is shown that it can be used as another raw material similarly to 0.5 mm particles. Further, it has been found that it is possible to recover the low asphalt-containing material with a specific gravity sorter, and it has been shown that the utility value and range of other raw materials are expanded according to the asphalt content.

Further, since the conventional recycled asphalt mixture is intended to be applied by blending with a general-purpose asphalt mixture in order to expand the use of the waste-asphalt mixture, the proportion of the general-purpose asphalt mixture is mixed because of the nature of the waste-asphalt mixture. Has been limited depending on the application.
Therefore, by removing the waste asphalt content adhering to the aggregate, the reuse rate of the aggregate is shown to be 100%, and it is considered that there is no problem if the amount of asphalt attached is 2% or less. .

In Table 3, the asphalt content of the recycled asphalt aggregate with light specific gravity is 2% or more, and it is shown that 100% of 2% or less cannot be recovered only by crushing and sieving. When used as a material, the necessity of the specific gravity selection process is shown from the viewpoint of quality stability. On the other hand, the asphalt content recovered as recycled asphalt is as low as 16.
It reaches 61% and is sorted by a specific gravity sorter.
In the 0.5 mm recycled asphalt mixture, the asphalt content reaches 81.00% as shown in the item No. 11 in Table 3. Therefore, as a fine particle regenerated asphalt mixture containing fine particle aggregates of -0.5 mm, it can be regenerated not only as an additive to the regenerated asphalt material but also as a reusable material as a waterproofing agent or a filler.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment By solving the problems of products produced from the above-mentioned existing facility for producing recycled asphalt mixture, product diversification and simplification and cost reduction of the process for producing existing recycled asphalt mixture are achieved. In order to achieve this, the present invention introduces the system shown in FIG. 5 separation / purification equipment flow of waste wood asphalt mixture into FIG. 6 general-purpose asphalt mixture production equipment flow.

To illustrate FIG. 5, as shown in FIG.
From existing waste asphalt mixture 24 particle size -13mm
Particles of the recycled asphalt aggregate are repeatedly collided with each other by a 25 fine pulverizer to separate the asphalt component and the aggregate component. Classified into 26 particle size-0.5mm high content asphalt mixture and 28 particle size + 0.5mm aggregate asphalt for waste material asphalt by 26 sieving machine, and 28 by 30 specific gravity sorter 30 high quality recycled asphalt aggregate and 31 high Content Separation and purification into recycled asphalt.

By introducing the system of FIG. 5 into the general-purpose asphalt manufacturing equipment shown in FIG. 6, the recycled raw material aggregate heating equipment and the recycled asphalt mixture manufacturing equipment shown in FIG. 2 or the existing system shown in FIG. As for the raw material crushing system, only the system after 21 steam box is unnecessary. That is, the purified and separated aggregate component can be used as a general-purpose aggregate, and the high-concentration asphalt component can be used for other purposes.

Second Embodiment The system shown in FIG. 5 can be applied to the recycled asphalt mixture manufacturing facility flow shown in FIG. 7. By introducing the system of FIG. 5 instead of the recycled raw material aggregate heating equipment shown in FIG. 2, operation and quality control of the recycled asphalt mixture manufacturing equipment become easy.

[0027]

Most of the waste asphalt mixture is road material and most of the owners are public institutions. Therefore, since the waste wood asphalt mixture is a public waste wood, it cannot be easily disposed of. Therefore, the waste material asphalt mixture is recycled as a recycled asphalt mixture for road materials, but not all are recycled. Even with the latest technology, the reuse rate of about 75% is the limit. Therefore, the storage amount of the waste wood asphalt mixture tends to increase. There is also a problem of deterioration of asphalt, and some asphalt cannot be reused.

In order to solve this problem, it is possible to increase the reuse rate as a raw material for recycled asphalt by separating and refining each component, and the aggregate component can be used as an ordinary aggregate for other purposes. The entire amount of asphalt mixture can be treated.

[0029]

[Brief description of drawings]

FIG. 1 is a flow sheet showing a method for producing an existing recycled asphalt aggregate.

FIG. 2 is a flow sheet showing an existing mechanical crushing type recycled asphalt mixture manufacturing facility.

FIG. 3 is a flow sheet showing an existing thermal crushing type recycled asphalt mixture manufacturing facility.

FIG. 4 is a flow sheet showing a separation / purification test of a waste wood asphalt mixture.

FIG. 5 is a flow sheet showing a separation / purification facility for a waste asphalt mixture.

FIG. 6 is a flow sheet showing a general-purpose asphalt mixture manufacturing facility.

FIG. 7 is a flow sheet showing a facility for producing a recycled asphalt mixture.

[Explanation of symbols]

1 waste wood asphalt mixture 2 recycled roadbed materials 3 primary crusher 4 vibrating screen 5 steam boxes 6 crusher 7 hot water tank 8 Hot air rotary kiln 9 crusher 10 sieving machine 11 Aggregate for recycled asphalt 12 dryer 13 Softening material 14 asphalt 15 stone powder 16 mixer 17 Recycled asphalt mixture 18 Heat dryer 19 General-purpose aggregate 20 Grizzly screen 21 steam box 22 Supplementary hopper 23 Crushing rotor 24 Grain size-13mm Aggregate for recycled asphalt 25 Fine crusher 26 sieving machine 27 Specific gravity sorter 28 + 0.5mm waste material asphalt mixture 29-0.5 mm high content asphalt mixture 30 High-quality recycled asphalt aggregate 31 High content recycled asphalt 32 General-purpose asphalt mixture

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yasuyuki Sone             15-2, Minami 8jo Nishi, Chuo-ku, Sapporo-shi, Hokkaido             No. Road Industry Co., Ltd. F-term (reference) 2D052 AA03 AA15 BA03 BA08 BA11                       BA23 DA21

Claims (5)

[Claims] 1. A plant for producing a general-purpose asphalt mixture by separating an asphalt component and an aggregate component from a waste asphalt mixture and recovering a high-grade aggregate component and a high-content asphalt by a specific gravity sorter. Manufacturing method of reusing as raw material of raw material or raw material of normal aggregate 2. A method of utilizing asphalt component adhering to the aggregate component in a waste asphalt mixture to 2% or less and using it as recycled aggregate other than aggregate for recycled asphalt. 3. An aggregate component separated and refined from a waste asphalt mixture is classified according to particle size, and used as a paving material, a spreading material,
Manufacturing method to reuse as curing sand 4. A regenerated asphalt mixture which is crushed from a waste wood asphalt mixture, extracted from a high-concentration regenerated asphalt mixture having a specific gravity of 0.5 mm or less and purified from a regenerated asphalt production plant and added to the regenerated asphalt mixture. Manufacturing method 5. A high-content recycled asphalt recovered according to claim 1, a waterproofing agent, an asphalt paving filler,
Method to use as an additive for asphalt mixture