KR100674127B1 - Material to improve quality of asphalt concrete, and the manufacturing method thereof - Google Patents

Abstract

The present invention relates to an asphalt concrete modifier chip (chip) that can effectively prevent plastic deformation of the asphalt concrete package installed in a high temperature region or a tropical region in the summer, more specifically, a plasticizer ( A mixture of a polymer of plastomer and an polymer of elastomer is diluted with banca C oil, coal tar, asphalt, etc., and an appropriate amount of one or two or more of calcium carbonate, carbon black, cement, limestone or calcined gypsum is added thereto as a filler. It is heated to 130-250 ℃ 30 minutes-3 hours, and added to and mixed with the crushed waste tire powder to maintain a heating state for 20 minutes or more, and then cooled and cut to produce an ascon modifier chip and a method of manufacturing the same. .

Ascon, Modifier, Plastic Strain

Description

Modified chip of asphalt concrete and its manufacturing method

1 is a conceptual diagram showing the action of the modifier in asphalt concrete,

Figure 2a is a conceptual diagram showing the combination of asphalt and modifiers,

Figure 2b is a conceptual diagram showing a state in which the asphalt is activated in the combination of Figure 2a,

3 is a reformer chip manufacturing apparatus used in the embodiment of the present invention.

The present invention relates to an asphalt concrete modifier chip used to improve the quality of asphalt concrete (hereinafter referred to as "ascon"), and more specifically, it is a polymer of a plasma polymer. Polyethylene Terephtalate (hereinafter referred to as "PET"), Styrene Butadiene Styrene (hereinafter referred to as "SBS"), an elastomer-based polymer, and Styrene Isoprene Styrene (hereinafter referred to as "PET") SIS ") or styrene butadiene rubber (Stylene Butadiene Rubber, hereinafter referred to as" SBR "), etc., are mixed and diluted with banca C oil, coal tar, asphalt, etc. As a filler, calcium carbonate, carbon black, cement, limestone Alternatively, one or two or more of gypsum gypsum is added in an appropriate amount and heated at 130-250 ° C. for 30 minutes to 3 hours, and then mixed with crushed waste tire powder for 20 minutes After being kept in a heated state, to a asphalt modifier chip and a manufacturing method for producing cooling and cutting.

Ascon is a mixture of asphalt and coarse aggregates, fine aggregates, and pavement fillers (limestone powder, cement, etc.) at room temperature or at room temperature. However, the asphalt contained in ascon is sensitive to changes in temperature, and ascon pavement is a plastic deformation in summer, which causes severe bends in the pavement, which hinders the traffic of cars. In some cases, cracks in the package may greatly shorten the life of the package.

Ascon modifier is used to improve the problem of ascon, and combines with asphalt to change the physical properties of asphalt, to prevent plastic deformation in summer, to prevent the formation of winter cracking, and to increase the slip resistance of the package. Do it.

Ascon modifiers that are widely used in the prior art include SBS or SIS, the concept that these modifiers act on the asphalt to change the physical properties of the asphalt is as shown in FIG. That is, modifiers such as SBS or SIS are generally used by adding about 2-5% of the amount of asphalt used in ascon, and when these modifier particles are combined with the asphalt particles, plastic deformation of the summer asphalt is prevented, Winter crack formation is prevented and the slip resistance of the package is increased.

These modifiers are as follows.

SBS is a polymer copolymerized by random reaction of high elastic butadiene and hardened styrene. When it is dissolved at high temperature and put into asphalt, it is a hard ascon mixture at high common temperature and resistant to fatigue cracking at medium common temperature. It is an elastic mixture that can be used, and a mixture having an unchanging stiffness that can resist temperature cracking even at a low common temperature.

However, SBS is required to be heated at a high temperature of 180 ° C and a high shear mixing device, which is a special mixing device, in order for the physical property to be melted at a high temperature, so that it can be mixed with the asphalt to be sufficiently mixed with the asphalt. Not only is it expensive, but also bulky, making it difficult to move to each asphalt plant. Therefore, in order to use SBS as an asphalt modifier, a heating device and a high shear mixing device are installed in an asphalt manufacturing plant, and SBS is pre-injected into the asphalt, mixed with asphalt sufficiently, and the asphalt containing the modifier is transported to the construction site. In addition, to do so, a separate asphalt tank must be installed in the asphalt manufacturing plant.

As such, the conventional method of using SBS as a modifier requires expensive equipment and requires a considerable time due to the complicated process. In addition, when the modifier is stored in a mixed state with the asphalt for a long time, separation of the asphalt and the modifier occurs and the effect of the modifier is not effective. Therefore, there is a problem in that it cannot be prepared in advance. Due to these problems, despite the excellence as a modifier of SBS, it is not yet widely used.

As a copolymer polymer of the same type as SBS, as a modifier of ascone, there is also SIS, which, like SBS, requires a high temperature heating device and a high shear mixing device, and also preserves the modifier for a long time in a mixed state with asphalt. If there is a problem of separation of asphalt and modifiers, there is a problem that can not be prepared and stored in advance, these modifiers are not yet widely used.

Grinded waste tires can also be used as modifiers because their physical properties are similar to copolymer polymers. Particularly, when the crushed waste tire is used as part of the road pavement material, not only is it useful in terms of resource recycling, but also the elasticity of the crushed waste tire creates elasticity on the road, and therefore, there is an advantage in that the riding comfort is good when driving on the road. . However, in the case of packaging by mixing the crushed waste tire with asphalt aggregate or the like, the crushed waste tire acts as a kind of foreign matter in the state in which the crushed waste tire is not integrated with the asphalt but is simply mixed, thus reducing the durability of the package. It will cause the result.

In order to solve the above problems in the use of grinding waste tires, there is a McDonald's method of the wet method. McDonald's method is a technology that uses 10-25% of crushed waste tires in asphalt and mixes the crushed waste tires and asphalt at high temperature and high speed at 190-220 ° C. for 30 minutes to 1 hour. That is, according to the McDonald's method, the asphalt and the crushed waste tires are mixed at a high speed at a high speed, so that the asphalt is firmly bonded to the crushed waste tire particles surface to form an integration.

However, in this McDonald's method, the pulverized waste tire and asphalt have to be kept at a high temperature continuously for more than 12 hours. Therefore, the pulverized waste tire may be completely dissolved in the asphalt. It may fall, and as a result may cause a problem that the overall quality of the asphalt concrete. In addition, in order to apply the McDonald's method, expensive aging equipment is required, and a mobile large asphalt tank, aging equipment, crushed waste tire truck, asphalt truck, aging personnel, etc. must be prepared. The disadvantage is that it is beneficial.

Another method of integrating the grinding waste tire and asphalt is the method of Patent No. 394092 proposed by the inventor of the present invention, which first indirectly heats the grinding waste tire to gel the surface of the grinding waste tire, and thus 150-300 By mixing the asphalt heated to ℃ to produce a chip in which the ground (gelled) crushed waste tire particles and asphalt integrated. This method is very economical compared to the above-described McDonald's method because it can integrate the grinding waste tire and asphalt in a simple process.

The concept of a chip manufactured by the method of Patent No. 394092 is as shown in FIGS. 2A and 2B. That is, as shown in Fig. 2a, the surface of the pulverized waste tire is first gelled and asphalt is bound to the gelled surface to be integrated as a whole, and as shown in Fig. 2b, the asphalt integrated with the crushed waste tire is additionally added later. It naturally binds and mixes with the asphalt particles. Thus, according to the method of the above patent, the crushed waste tires are more firmly bonded with the asphalt (not simply mixed).

However, the main purpose of using the crushed waste tires is to improve the riding comfort when driving the vehicle by providing environmental protection and resilience to the package through the recycling of resources, the use of crushed waste tires does not improve the durability of the package. Therefore, when using the crushed waste tire, there is a need to separately devise a method for improving the durability of the package, Patent No. 394092 has not been proposed for such a durability improvement.

On the other hand, in order to improve the problems of the conventional reforming materials as described above, the inventors in the patent application No. 2004-56041 filed on July 19, 2004, the asphalt is melted by heating to 180-250 ℃ and SBS, SIS or Manufacture of modified chips for producing chips by adding low-density polyethylene (Low Density Polyethlene: hereinafter referred to as "LDPE"), mixing and heating them, and then cooling, pulverizing, or cutting chips while discharging them to a predetermined size using an extruder. I have suggested a method. The reformer chip produced by this method does not require any expensive equipment or complicated process in its use compared to the conventional reformer, and can be said to be very useful because of its excellent effect.

However, since the invention of the patent application uses an elastomer-based SBS or SIS as the main material, the effect of preventing plastic deformation in summer is not sufficient. Although the invention of the patent application includes the use of low density polyethylene (Low Density Polyethlene: hereinafter referred to as "LDPE") of the plasma system, LDPE alone could not sufficiently prevent the plastic deformation in the summer of ascon packaging. .

The present invention has been made to solve the problems of the conventional modifiers described above. A large amount of PET is used to manufacture the modifier chip of the present invention, because the PET is a polymer of a plastomizer-based polymer, and thus has a great effect of preventing plastic deformation of the asphalt concrete packaged in an area having high summer temperatures or in the tropics. In addition, PET is a fibrous plastic that has tough physical properties, which can improve the durability of Ascon, as well as the recycling of resources in that waste PET beverage bottles can be used as materials. Is large.

Accordingly, an object of the present invention is to firstly, by forming a modifier into chips so that no additional expensive equipment or complicated process is required for input into the ascon material, and secondly, the region having high summer temperature by using PET or To sufficiently prevent plastic deformation of ascon pavement in the tropics, third, to improve durability of ascon pavement by using PET, and fourth, to recycle resources by using waste PET, and Fifth, by manufacturing and using a chip mixed with a grinding waste tire and a modifier material, while utilizing the advantages of using the grinding waste tire and at the same time to prevent the problem of durability degradation that can be caused by using the grinding waste tire. .

Ascon modified chip of the present invention (Chip) is a process of mixing 1 part by weight of PET, a polymer of the plasma-based polymer, SBR 0.05-1 parts by weight of the polymer of the elastomer (elastomer); Diluting the mixture of the above process by adding 0.5-3 parts by weight of one or two or more selected from diluent banca C oil, coal tar and asphalt; Adding 0.1-2 parts by weight of at least one of calcium carbonate, carbon black, cement, limestone or calcined gypsum as a filler to the mixture of the above step and mixing the mixture; Heating the mixture of the above steps to 130-250 ° C. for 30 minutes-3 hours to obtain a gel state; Mixing 0.1-3 parts by weight of pulverized waste tire powder into the heated mixture of the electric process and maintaining the heated temperature of the electric process for 20 minutes or more; And producing a chip of a predetermined size by cooling the mixture to be gelled in the electric process by air or water cooling and cutting the cooled to a predetermined size.

Since the modifier chip of the present invention may be stored in a suitable container and then used in an ascon mixer at an ascon packaging site, the use of the modifier chip of the present invention can greatly simplify the manufacturing process of ascon in the field. .

As described above, in the present invention, the reason for using PET, which is a polymer of the plasma system, as the main material is to effectively prevent plastic deformation in summer of ascon packaging. However, when only PET is used, there is a problem in that it is vulnerable to cracking caused by low temperature in winter, and in order to solve such a problem, it is necessary to replenish an appropriate amount of SBS, SIS or SBR, which is an elastomer-based polymer. In the present invention, 1 part or more of SBS, SIS or SBR is added by 0.05-1 part by weight to 1 part by weight of PET.
In the above, PET was invented as a synthetic fiber raw material, called polyether terephthalite, and is an important material that currently accounts for 50% of synthetic fiber production, and has very excellent characteristics as a raw material for packaging plastic films and sheets.
The PET has a melting temperature of 240 ° C. or higher, and is a fibrous structure at a low temperature of 100 ° C. or lower, and thus has a high resistance to heat. Therefore, when added to asphalt, the softening point of the asphalt can be increased. It is very effective in preventing thermal plastic deformation in the area, and in addition, the fiber structure is effective in terms of connection reinforcement of asphalt, thereby increasing the durability of asphalt concrete by firmly bonding the asphalt.

In the use of elastomeric polymers, it is necessary to add more elastomeric polymers such as SBS, SIS or SBR in areas where the winter cold is severe, whereas in areas where the temperature rise in the summer is more important than the winter temperature decrease. In this case, what is necessary is just to add the polymer of these elastomer systems to the minimum.

It is necessary to dilute these polymers in order to sufficiently mix the polymers such as PET and SBS, SIS or SBR with the filler (added in a later process). At this time, as a diluent (solvent) for diluting the polymer, high asphaltene content, high flash point (over 400 ° C), low flow temperature (about 50 ° C), and cheap banca C oil, coal tar, asphalt, etc. It is windy. The amount of diluent is preferably 0.5-3 parts by weight based on 1 part by weight of PET. The reason for this is that when the amount is 0.5 parts by weight or less, the polymer may not be dispersed properly. This is because it becomes unnecessary.

The diluent is preferably added after the mixing process of the polymers (before adding the filler), but the diluent may be added after the filler is added to the polymer. However, when diluent is added after the filler is added to the polymer, the amount of diluent should be somewhat increased (to allow the diluent to be in sufficient contact with the polymer).

In the present invention, 0.1-2 parts by weight of one or more of calcium carbonate, carbon black, cement, limestone or calcined gypsum should be added as the filler, and the purpose of using the filler is to modify it in addition to improving the strength and durability of the asphalt concrete in the future. This is to adjust the viscosity of the ash so that the chip production (formation) is easy, and when the modifier chip is put into the asphalt, the polymers (mixed with the filler) in the modifier are well dispersed throughout the asphalt. . The amount of the filler used is preferably 0.1-2 parts by weight based on 1 part by weight of PET. If the content is 0.1 parts by weight or less, it is not easy to produce (form) chips and disperse the polymer in the future. If the weight part or more, the volume of the modifier chip as a final product is unnecessarily large, resulting in inconvenience in transportation or use.

After sufficiently mixing the mixture of the polymer, the diluent and the filler, the mixed mixture is heated to 130-250 ° C. for about 30 minutes to 3 hours to obtain a gel state.

In the modifier chip of the present invention, in addition to the above-described materials, the grinding waste tire powder is added and mixed, thereby enjoying the effects of resource recycling and elasticity of the road pavement, which are advantages of using the grinding waste tire. At the same time, chip formation can be facilitated (because the grinding waste tire powder serves as an agglomeration of the gelled mixture).

In further mixing the ground waste tire powder, the ground waste tire powder is further mixed with a mixture of the polymer, the diluent and the filler heated to 130-250 ° C. (described above), and maintained at a high temperature for at least 20 minutes. As described above, the chip may be cooled and cut while being discharged through a discharge net of a sieve net or a perforated net. The reason for maintaining the pulverized waste tire powder for 20 minutes or more at a temperature of 130-250 ° C is to allow the surface of the pulverized waste tire powder to gel. If the surface of the crushed waste tire powder is not gelled, the crushed waste tire powder may not sufficiently bind with asphalt in future asphalt concrete packaging.

In the present invention, it is preferable to use the amount of the crushed waste tire powder in an amount of 01.-3 parts by weight based on 1 part by weight of PET. If it is used at 0.1 parts by weight or less can not bring the effect of the use of crushed waste tires, on the other hand, when used at 3 parts by weight or more there is a problem that the amount of the modifier chip to be used in the field unnecessarily increases.

In order to prepare the gel-like mixture in the form of chips, it must be cooled by air or water cooling while being discharged to the outside through a conveying screw or the like.

Cooling method suitable for the present invention is discharged through the discharge port consisting of a sieve or perforated network through a transfer screw, etc., cooling by spraying the lime water (02.-5% of limestone powder dissolved) to the discharged mixture Simultaneously with cutting, it is cut into a rotary cart and manufactured in the form of a chip. The reason for using lime water is to quench the temperature of the mixture while at the same time preventing the discharged (gel) mixture from entangled with each other.

In manufacturing the chip, the size of the object to be crushed or cut is preferably as small as 5 mm or less, preferably 3 mm or less. The reason for reducing the size of the modifier chip of the present invention is to reduce the time it takes to soften in the asphalt concrete mixer.

In the modifier chip manufacturing method of the present invention, sulfur, paraffin, glue, rosin (for strengthening adhesion) may be mixed (for strength improvement), optical fibers, cellulose fibers (for durability), if necessary. And reinforcing fibers such as polymer fibers may be added. Of course, if necessary, UV agents may be added for protection from ultraviolet rays, and PVC, EVA, PP, or PE may be added to improve strength and durability. By using such materials in the present invention, it is possible to maximize the quality of ascon.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated based on an Example.

(Example)

In the case of paving ascon road for vehicle traffic by setting the 200m section, the paving method was changed in units of 100m, paving A is a general ascon paving without adding the modifier chip of the present invention, and paving B is the reforming of the present invention. Ascon packaging with ash chips. The modifier used in Package B in this example is prepared by the material blending ratio and process shown in Table 1 below.

Table 1: Formulation ratio of modifier material used in this example

Material name Waste PET SBS Calcium Carbonate (700 mesh) Banca C oil Rosin Grinded tires (0.6㎜ or less) Material usage (kg) used to produce 100㎏ modifier 25 5 5 45 2 18

The reformer chip manufacturing apparatus used in this embodiment is as shown in FIG. As shown in Fig. 3, a heating device is attached to the bottom of the mixer so that it can be heated at the same time as mixing, and a heating wire (heating means) is provided on the outer surface of the conveying screw even when the mixed heated mixture is transferred to the outlet. Since it is provided and can continue heating to predetermined temperature even while a mixture is conveyed, it can prevent that a mixture cools (hardens) and adheres to a screw etc. during conveyance.

And the outlet is attached to the sieve of 20 mm in length and 5 mm in sieve size, the rotary cutter is installed on the outer front of the outlet, it is possible to adjust the length of the chip cut by the adjustment of the rotation speed. In addition, the discharge port is installed directly under the discharge port, and the conveyor belt is installed in the discharge port, so when discharged through the discharge port, the lime water is sprinkled and finely cut by the rotary cutter. It was dropped in the lime water bath, cooled, and then transferred to a predetermined place through the conveyor belt.

The modifier chip was manufactured by the following process using the ingredients of the above mixing ratio and the manufacturing method of FIG.

First step: the waste PET and SBS was pulverized into a granular state and mixed well, and then calcium carbonate, banca C oil and rosin powder were added and mixed, and the mixture was heated to 220 ° C. for 30 minutes.

Second step: The waste tire was put into the mixture of the first step and heated again to 220 ℃ for 30 minutes.

Third process: The heated mixture of the second process was transferred from the mixer to the lower hopper and again discharged to the outlet using a screw feeder connected to the hopper.

Fourth process: The size of the chip was adjusted to 5 mm by controlling the speed of the rotary cutter on the front of the outlet, and the chips were cooled using lime water. The cooled chips were sufficiently dried by air while being transported by the conveyor belt, and then crushed and stored to have a size of 3 mm.

Package A is an ascon package without a modifier, and package B is an ascon package using the modifier chip of this embodiment. The packaging materials used for Pavement A and B are almost the same as those for general Ascon pavement, and the materials used are shown in Table 2 below.

Table 2: Materials Used for Packaging A and B

division asphalt aggregate Filler (CaCo ₃ ) Modifier system Remarks Packing A 5.5 91.5 3.0 - 100 unit : % Packing B 5.5 90.6 3.0 0.9 100

The particle size and synthetic particle size distribution of the aggregate used in this example (gap particle size basis: CaCo ₃ as a filler 3%) are shown in Table 3 below.

Table 3: Aggregate particle size distribution

Checker (mm) 19 13 10 #4 #8 # 30 # 200 Remarks % Of weight passed 100 100 81.0 35.7 19.6 11.7 6.2 Aggregate used 100 90-100 70-90 24-42 15-25 5-15 3-7 Composite particle size distribution

In this example, the materials were heated and mixed at 155-163 ° C. and transported to the site by a dump truck for installation. For package B, the modifier of this example was added to the ascon mixer in the field, mixed and used immediately. In the field installation, the installation was carried out with a finisher according to a conventional method, followed by a commitment to Macadam and Dendom Laura.

In this example, the package stability of the package A and package B, the dynamic stability, the recovery modulus and the amount of wear were tested, the results are shown in Table 4.

Table 4: Test Results for Packages

Item Name Item Packing A Packing B standard Dynamic Stability (times / mm) 360 10,120 1,500 or more Recovery modulus of elasticity: 5 ℃ (MPa) 9,540 3,750 - Abrasion amount (㎠) (labeling test) 1.270 0.320 -

As shown in Table 4, in case of package B, the dynamic stability, which is a criterion for plastic deformation, increased sharply compared to package A without using the modifier. Particularly, in the case of ascone using a modifier chip of Patent No. 2004-56041 filed by the present inventor (the invention relates to a modifier chip manufactured using SBS or SIS of an elastomer system as a main material), the dynamic stability is high. In contrast to 8,500, the present embodiment is significantly higher than this.

In addition, the elastic recovery coefficient at low temperature, which is the basis of low temperature cracking, was stabilized at a level of 1/3 compared to the package without the modifier (packaging A), and the amount of abrasion by labeling test was also used without the modifier (packaging Compared to A), it developed to about one quarter level.

Therefore, it was confirmed that the asphalt concrete modifier chip of the present invention has an excellent effect of preventing plastic deformation in summer.

The present invention relates to polyethylene terephtalate (hereinafter referred to as "PET"), which is a polymer of a plasomer series, and styrene butadiene styrene (hereinafter, "SBS"), which is a polymer of an elastomer system. By using styrene isoprene styrene (hereinafter referred to as "SIS") or styrene butadiene rubber (stylene butadiene rubber (hereinafter referred to as "SBR")), it is possible to effectively prevent summer plastic deformation of ascon. This is particularly useful for ascon pavement, especially in tropics and areas where summer temperatures are very high.

Claims (6)

Mixing 1 part by weight of PET and 0.05-1 part by weight of SBR; Dilution by adding 0.5-3 parts by weight of the diluent to the mixture of the above process; Adding 0.1-2 parts by weight of filler to the mixture of the above step and mixing the mixture; Heating the mixture of the above steps to 130-250 ° C. for 30 minutes-3 hours to obtain a gel state; Mixing 0.1-3 parts by weight of pulverized waste tire powder into the heated mixture of the electric process and maintaining the heated temperature of the electric process for 20 minutes or more; And manufacturing a chip of a predetermined size by cooling the mixture to be gelled in the electrical process and cutting the cooled to a predetermined size. delete The method of claim 1, wherein the diluent is one or more selected from banca C oil, coal tar, asphalt asphalt concrete modifier chip manufacturing method. The method of claim 1, wherein the filler is one or more of calcium carbonate, carbon black, cement, limestone or calcined gypsum. The method of claim 1, wherein lime water is used as the cooling means. Asphalt concrete modifier chip prepared according to claim 1.

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