KR20220049079A - Exothermic asphalt mixture with mixed waste anode materials and construction method of pavement structure - Google Patents

Abstract

The present invention relates to an exothermic asphalt mixture mixed with a waste negative electrode material, wherein the mixture includes an asphalt binder, a waste negative electrode material, and aggregate. According to the present invention, the mixture has excellent environmentally friendly properties and improved exothermic efficiency.

Description

Exothermic asphalt mixture with mixed waste anode materials and construction method of pavement structure

The present invention relates to a method for constructing an exothermic asphalt mixture and pavement structure in which heat efficiency is improved by adding a waste cathode material.

The asphalt mixture is made using an asphalt binder and aggregates including coarse and fine aggregates. When moisture exists on the pavement surface due to snow or rain in winter, the pavement structure made of this asphalt mixture freezes due to the low temperature. are doing

Accordingly, in Korean Patent Registration No. 10-1844770, based on 100 parts by weight of asphalt, 10 to 30 parts by weight of a phase change material; 5 to 50 parts by weight of styrene isoprene styrene; 5 to 50 parts by weight of styrene butadiene styrene; 2 to 15 parts by weight of a UV absorber; 10 to 1,000 parts by weight of sand; 2 to 15 parts by weight of an anti-deformation agent; 5 to 40 parts by weight of lime powder; 10 to 40 parts by weight of nano-ceramic particles; 10 to 40 parts by weight of waste tire powder; 2 to 15 parts by weight of a rubber anti-aging agent; 3 to 15 parts by weight of perfluoromethoxysilane; 1 to 10 parts by weight of a stabilizer; 1 to 10 parts by weight of a performance improving agent; 2 to 20 parts by weight of fiber; Adhesion enhancer 5 to 20 parts by weight; And presenting an exothermic asphalt concrete composition comprising 0.1 to 5 parts by weight of an antioxidant.

However, in the case of the above technology, there is a problem in that it is difficult to expect sufficient heat generation.

Korean Patent Registration No. 10-1844770

An object of the present invention is to provide a method for constructing an exothermic asphalt mixture and pavement structure in which sufficient heat efficiency can be expected even with a small amount of energy by adding a waste cathode material.

As a means for solving the above-mentioned problems, the exothermic asphalt mixture (hereinafter referred to as the "mixture of the present invention") incorporating the waste cathode material of the present invention is characterized in that it includes an asphalt binder, a waste cathode material, and aggregate.

As an example, it is characterized in that carbon fiber is further included.

As an example, it is characterized in that carbon nanotubes are further included.

In addition, the construction method of the exothermic asphalt pavement structure incorporating the waste anode material of the present invention (hereinafter referred to as "the construction method of the present invention") includes the steps of stirring a composition in which an asphalt binder, a waste cathode material, and aggregate are mixed (S10); Casting and curing the composition (S20); characterized in that it comprises.

As an example, the carbon nanotube dispersion is further mixed in step S10.

As an example, in the step S10, the carbon nanotube dispersion is mixed with liquid carbon nanotube, water, and a polycarboxylic acid-based water reducing agent in a stirring vessel, and an ultrasonic generator is operated to prepare a carbon nanotube dispersion.

As an example, the stirring container consists of an inner container and an outer container, the outer container is filled with cooling water, and liquid carbon nanotubes, water, and a polycarboxylic acid water reducing agent are put into the inner container configured inside the outer container. It is characterized in that the carbon nanotube dispersion is prepared while controlling the temperature rise by generating ultrasonic waves by the ultrasonic generator.

As an example, the inner container inside the outer container is supported by a support including a heat transfer bar made of a plurality of thermally conductive materials and a thermal barrier coating on its outer periphery. It is characterized in that the carbon nanotube dispersion is prepared.

As described above, the mixture and construction method of the present invention have the advantage of being environmentally friendly because waste materials can be recycled.

In addition, the mixture and construction method of the present invention has the advantage of increasing the heat generation efficiency with a small amount of energy.

1 is a graph showing the heat generation performance of each embodiment of the present invention.
Figure 2 is a block diagram showing the construction method of the present invention.
Figure 3 is a schematic view showing an example of a reaction vessel used in the construction method of the present invention.
Figure 4 is an operation state diagram of another example of the reaction vessel shown in Figure 3;

Hereinafter, the configuration and operation of the present invention will be described in more detail based on the accompanying drawings. In describing the present invention, the terms or words used in the present specification and claims are based on the principle that the inventor can appropriately define the concept of the term in order to best describe his or her invention. It should be interpreted as meaning and concept consistent with the technical idea of

The mixture of the present invention is characterized in that it contains an asphalt binder, a waste anode material, and aggregate.

The asphalt binder is not limited to the type of general asphalt or pure asphalt, and may be used by mixing general asphalt and pure asphalt. Here, 'pure asphalt' is defined as minerals removed from natural asphalt. Natural asphalt has a bulk form, and natural asphalt contains minerals containing calcium carbonate as a main component. As such, natural asphalt contains minerals, so if natural asphalt is used as it is, it acts as a factor hindering the formation of a tight and durable paste by lowering the adhesion between compositions, etc. Therefore, it is preferable to use pure asphalt.

The waste anode material is for generating a heat-generating function in the paste.

Lithium secondary batteries used in electric vehicles and small home appliances are composed of an anode, a cathode, a separator, and an organic electrolyte. Transition metal oxide is used as an anode material and carbon is used as a cathode material. In particular, the anode material has a size of 10 to 18㎛ and contains natural graphite, artificial graphite, low-crystalline carbon, metal-based, CNT, graphene, etc., so that it can have electrical conductivity in asphalt, which is an insulator.

Currently used graphite reaches 10,000 ~ 80,000 won/kg, and when graphite is mixed in a large amount in the asphalt mixture, difficulties arise in R&D and product production due to cost limitations. Accordingly, in the present invention, the waste anode material generated from the waste lithium secondary battery is used, and when the waste cathode material is used, it is possible to secure price competitiveness of 1/20 to 1/50 or more compared to the existing graphite products, By recycling the anode material, resource circulation and environmental pollution can be prevented.

As for the particle size of the aggregate, it is reasonable that 12.5mm is 100-90%, 4.75mm is 74-44mm, 2.36mm is 58-28%, 0.3mm is 21-5, and 0.075mm is 10-2%.

Preferably, it is appropriate to mix 50 to 150 parts by weight of aggregate and 5 to 30 parts by weight of a waste anode material based on 100 parts by weight of the asphalt binder.

In addition, the mixture of the present invention may further include carbon nanotubes to further double the heat generating function.

The carbon nanotube (CNT) is a new material in the form of a cylinder in which hexagons made of 6 carbons are connected in a tubular shape, which allows the exothermic function to be expressed in the mixture of the present invention. These carbon nanotubes have physical properties such as light weight, high mechanical rigidity, excellent electrical conductivity and high thermal conductivity.

Preferably, it is reasonable to mix 5 to 30 parts by weight of carbon nanotubes with respect to 100 parts by weight of the asphalt binder.

The carbon nanotubes may be formulated as a powder or dispersion.

The carbon nanotube dispersion is characterized in that it is prepared by mixing liquid carbon nanotubes, water, a polycarboxylic acid-based water reducing agent, and polyvinylpyrrolidone. The liquid carbon nanotubes are diluted in water to prepare a carbon nanotube dispersion.

In general, carbon nanotube particles have an attraction between particles due to a strong Van der Waals attraction, which results in self-aggregation. Due to these characteristics of carbon nanotubes, there is a limitation in dispersing the carbon nanotube particles themselves into fine particles in the paste and maintaining the dispersibility of the dispersed fine particles. In particular, carbon nanotubes have a very low specific gravity, so they are not evenly distributed during mixing, and because they float to the surface, it is difficult to achieve uniform dispersion.

Accordingly, in the present invention, the dispersion is to further include a polycarboxylic acid-based water reducing agent so that the carbon nanotubes are uniformly dispersed.

The polycarboxylate-based water-reducing agent is used. In the polycarboxylic acid-based water-reducing agent with a long main chain, the carboxyl group (COO-) effectively induces the initial dispersion of the cement, thereby reducing the unit quantity and hydrating the cement to increase the strength. to express

In addition, it is preferable to further contain a polycarboxylate-based oil-retaining agent together with the polycarboxylate-based water reducing agent. When the main chain of the carboxyl group (COO-) of the polycarbonate-based retaining agent with a long side chain is embedded in the cement hydrate product, the secondary dispersion ability of the side chain serves to maintain workability for a long time.

In the dispersion, in the case of liquid carbon nanotubes, water, polycarboxylic acid-based water reducing agent, and polycarboxylic acid-based retaining agent, it is natural that the mixing ratio can be selectively adjusted according to various factors such as the concentration and use of liquid waste CNTs.

In order to express a predetermined conductivity or strength-reinforcing performance, networking must be formed between the waste cathode materials or carbon nanotubes as a filler. In addition, the carbon fiber is further mixed.

The carbon fiber is defined as a fiber that is carbonized and crystallized by heat-treating an organic fiber at an appropriate temperature in an inert gas, and the carbon fiber exhibits mechanical properties such as high strength and high rigidity made of graphite carbon. In this way, carbon fibers are incorporated to improve crack resistance through cross-linking, and carbon fibers have electrical conductivity, which imparts electrical conductivity to the paste.

In particular, the carbon fiber has a significantly greater long axis ratio than that of carbon nanotubes, so networking is further strengthened. By connecting the agglomerated parts, the conductivity is further strengthened to double the heating efficiency.

That is, when the water/binding material ratio (w/c) increases for workability, etc., the aggregation phenomenon of carbon nanotubes or waste cathode materials increases. Between carbon nanotubes aggregated by carbon fibers, between waste cathode materials, Since the carbon nanotube and the waste cathode material are electrically connected to each other, the formation of a conductive disconnection section is controlled.

In addition, when cracks occur in the asphalt, the above-mentioned conductive disconnection section is formed in the cracked part, and by adding carbon fibers, the cracks of the paste are controlled through the crosslinking action of the carbon fibers to solve this problem.

Preferably, it is appropriate to mix so that 1 to 3 parts by weight of carbon fibers are included with respect to 100 parts by weight of the asphalt binder.

Hereinafter, a test was performed to evaluate the exothermic effect of the mixture of the present invention. Specimens used in the run were applied with a 13 mm density asphalt mixture particle size. Table 1 below is the particle size applied to the specimen.

Sieve size (mm) passing weight percentage 12.5 (mm) 12.5 (1/2") 90-100 4.75 (#4) 44-74 2.36 (#8) 28-58 0.30 (#50) 5-21 0.075 (#200) 2-10

As the asphalt binder used to prepare the mixture, a straight asphalt binder of grade PG (Perfomance Grade) 64-44 was used.

In addition, in the case of Example 1, it is an example in which 20 parts by weight of a waste anode material is included with respect to 100 parts by weight of the asphalt binder, and in the case of Example 2, it is mixed in the same manner as in Example 1, but 3 parts by weight of carbon fiber is further mixed. And, in the case of Example 3, it is the same as Example 2, but is an example in which 10 parts by weight of carbon nanotubes are further blended.

From the experimental results, it can be seen that Example 2 has better heat generation efficiency than Example 1, which is a point where carbon fibers connect agglomerated parts between waste cathode materials to strengthen conductivity and crosslinking action, as mentioned above. It is judged that this is due to the control of cracking by , and it can be seen that the case of Example 3 has better heat generation efficiency than that of Example 2, which is judged to be due to the addition of more carbon nanotubes.

Meanwhile, the present invention also discloses the above-mentioned asphalt construction method as shown in FIG. 2 . As shown in FIG. 2, the construction method of the present invention includes agitating a composition in which an asphalt binder, a waste anode material, and aggregate are mixed (S10); Casting and curing the composition (S20); characterized in that it comprises.

In addition to this, in step S10, the carbon nanotube dispersion is further mixed, and the carbon nanotube dispersion is mixed with liquid carbon nanotubes, water, and a polycarboxylic acid water reducing agent in a stirring vessel, and then the ultrasonic generator is operated to generate carbon Characterized in preparing a nanotube dispersion.

However, heat is generated in the process of preparing the carbon nanotube dispersion using ultrasonic waves, and this heat acts as a factor that deteriorates the carbon nanotubes, so there may be a problem in that the expression of the above-mentioned functions is inhibited.

Accordingly, in the present invention, an example in which step S10 is performed using the stirring vessel 1 shown in FIG. 3 is presented.

In this embodiment, the stirring vessel (1) is composed of an inner container (2) and an outer container (3) as shown in Fig. 3, the outer container (3) is filled with cooling water (5), the outer container Liquid carbon nanotubes, water, and a polycarboxylic acid-based water reducing agent are put into the inner container (2) configured in (3), and ultrasonic waves are generated by the ultrasonic wave generating port (4) in the inner container (2). It is characterized in that the carbon nanotube dispersion 6 is prepared while the temperature rise is controlled.

In this embodiment, the ultrasonic generating port ( By 4), the heat generated in the process of stirring a stirring object made of liquid carbon nanotubes, water, and a polycarboxylic acid water reducing agent can be lowered by heat exchange.

Here, since the ultrasonic generator 4 has a variety of known technologies, a detailed description thereof will be omitted.

In addition to this, in the present invention, an embodiment in which the deterioration of carbon nanotubes can be controlled while allowing easy stirring by selectively performing heat exchange according to the temperature of the outside air is shown in FIGS. 4A and 4B .

In this embodiment, the inner container (2) inside the outer container (3) is a heat transfer bar (71) of a thermally conductive material and a plurality of supports (7) including a thermal barrier coating (72) on its outer periphery. It is characterized in that the carbon nanotube dispersion 6 is prepared by selectively filling the cooling water 5 between the outer container 3 and the inner container 2 according to the external temperature.

That is, in this embodiment, the inner container (2) inside the outer container (3) is configured while forming mutually spaced apart by a plurality of supports (7), the support (7) is a heat transfer bar (71) of a thermally conductive material and It is characterized in that it includes a thermal barrier coating (72) on its outer periphery.

The heat transfer bar 71 is configured to dissipate the heat H1 of the inner container 2 to the outside, and the material must of course be made of a thermally conductive material. The heat barrier coating 72 surrounding the heat shear bar 71 is to block the heat transfer between the heat transfer bar 71 and the outside, and in FIG. 4a, the heat transfer bar 71, the outer container 3, and the inner container (2) The heat transfer between the air is blocked so that the heat (H1) generated by ultrasonic dispersion, which will be described later in the inner container 2, is dissipated to the outside of the outer container 3, and in FIG. 4b, the heat transfer bar 71 ) and the cooling water (5) to block the heat transfer so that only the cooling water (5) and the carbon nanotube dispersion (6) are heat transfer. Here, in the case of the thermal barrier coating 72, various well-known materials exist, so a detailed description thereof will be omitted.

When explaining the operating state of this embodiment, Fig. 4a shows that when the external temperature is low, especially in winter, when a low external temperature is transmitted to the carbon nanotube dispersion 6, the dispersion itself is not well made, so that the carbon nanotubes are aggregated. There is a problem that the dispersion 6 can be manufactured. In this case, between the outer container 3 and the inner container 2, the function of a thermal barrier layer to block the transfer of external air to the inner container 2 is expressed. This is to prevent the carbon nanotube dispersion 6 inside the inner container 2 from becoming low enough to cause dispersion degradation, and in the case of heat (H1) generated in the dispersion process by ultrasonic waves, the heat transfer bar 71 ) to control the deterioration of carbon nanotubes during the dispersion process by dissipating heat to the outside.

That is, FIG. 4a shows that the carbon nanotube dispersion 6 inside the inner container 2 is prevented from being so low that it is difficult to disperse in winter, and the heat (H1) generated in the dispersion process by ultrasonic waves is radiated to the outside to radiate carbon. It is to control the degradation of nanotubes.

In addition, Figure 4b shows the case of the outer container 3 and the inner container 2 in the case of the summer season, etc., when the deterioration of the carbon nanotubes can be caused only by the transfer of external air to the carbon nanotube dispersion 6 inside the inner container 2 . ) to fill the cooling water 5 between The heat transfer bar 71 is used to dissipate heat to the outside to control deterioration of carbon nanotubes due to dispersion by external air and ultrasonic waves.

As mentioned above, a carbon nanotube dispersion is prepared, and a composition in which an asphalt binder, a waste anode material, a carbon nanotube dispersion, and aggregate are mixed is stirred (S10). The asphalt binder, the waste anode material, the carbon nanotube dispersion, and the aggregate are stirred so that the waste anode material, particularly with small particles, is sufficiently dispersed between the asphalt binder and the aggregate.

Finally, there is a step (S20) of pouring and curing the composition. In this step (S20), the composition is poured and cured according to the use. Depending on the use, the composition is poured and cured in a state in which the electrode is already installed in the form, so that the structure in which the electrode is embedded is manufactured or constructed. to make it possible

Those skilled in the art from the above description will be able to see that various changes and modifications are possible without departing from the technical spirit of the present invention. Accordingly, the technical scope of the present invention should not be limited to the content described in the detailed description of the specification, but should be defined by the claims.

1: stirring container 2: inner container
3: External container 4: Ultrasonic generator
5: cooling water 6: carbon nanotube dispersion

Claims (8)

An exothermic asphalt mixture containing an asphalt binder, a waste anode material, and a waste cathode material including aggregate.
The method of claim 1,
Exothermic asphalt mixture containing a waste anode material, characterized in that it further contains carbon fibers.
The method of claim 1,
Exothermic asphalt mixture incorporating a waste cathode material, characterized in that it further contains carbon nanotubes.
agitating the composition in which the asphalt binder, the waste anode material, and the aggregate are mixed (S10);
pouring and curing the composition (S20);
A method of constructing an exothermic asphalt pavement structure incorporating a waste anode material, characterized in that it comprises a.
5. The method of claim 4,
The construction method of the exothermic asphalt pavement structure incorporating the waste cathode material, characterized in that the carbon nanotube dispersion is further mixed in the step S10.
6. The method of claim 5,
In the step S10, the carbon nanotube dispersion is mixed with liquid carbon nanotubes, water, and a polycarboxylic acid-based water reducing agent in a stirring container, and an ultrasonic generator is operated to prepare a carbon nanotube dispersion. A construction method of a heat-generating asphalt pavement structure.
7. The method of claim 6,
The stirring container is composed of an inner container and an outer container, the outer container is filled with cooling water, liquid carbon nanotubes, water, and a polycarboxylic acid-based water reducing agent are put into the inner container configured inside the outer container, and an ultrasonic wave generating port A method of constructing an exothermic asphalt pavement structure incorporating a waste cathode material, characterized in that the carbon nanotube dispersion is prepared while controlling the temperature rise by generating ultrasonic waves.
8. The method of claim 7,
The inner container inside the outer container is supported by a support including a heat transfer bar made of a plurality of thermally conductive materials and a thermal barrier coating on its outer periphery. A method of constructing an exothermic asphalt pavement structure incorporating a waste anode material, characterized in that a nanotube dispersion is prepared.

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