KR101029912B1 - Modifier for manufacturing low or mid temperatured asphalt concrete and asphalt concrete with low carbon dioxide emission using the modifier - Google Patents

Abstract

PURPOSE: A modifier for low-mid temperature asphalt concrete and the low-mid temperature asphalt concrete using the same are provided to improve the mixing property and the hardening property of the asphalt concrete by using a superplasticizer, a particle adhesion preventive agent, and processing oil. CONSTITUTION: A base material containing crushed waste tire, heat expandable vermiculite, and cellulose fiber is prepared. Modifying fluid and a particle adhesion preventive agent are added to the base material. A mixing process is implemented under the temperature of 100 to 150 degrees Celsius in order to obtain a mixture. The mixture is cooled to temperature lower than 50 degrees Celsius. Processing oil, rosin, and ethylene vinyl acetate are added to the cooled mixture.

Description

MODIFIER FOR MANUFACTURING LOW OR MID TEMPERATURED ASPHALT CONCRETE AND ASPHALT CONCRETE WITH LOW CARBON DIOXIDE EMISSION USING THE MODIFIER}

The present invention relates to a road pavement that can reduce the emissions of carbon dioxide, and in particular to the low-temperature asphalt concrete additives and low-carbon asphalt mixture using the same for producing an asphalt concrete mixture produced at low temperature (80 ℃ ~ 135 ℃) will be.

In general, medium temperature asphalt concrete refers to the production temperature of asphalt concrete is 100 ℃ ~ 135 ℃, low temperature asphalt concrete refers to the production temperature of asphalt concrete is less than 100 ℃. The present invention relates to low-temperature low-temperature asphalt concrete produced at 80 ℃ ~ 135 ℃, looking at the reason for the need for low-temperature asphalt concrete.

Asphalt is a thermosensitive material that turns into a liquid and hardens at low temperatures when heat is applied.As a result, asphalt, aggregate, or both of them are heated at a predetermined temperature in order to increase workability (WORKABILITY, fluidity, compaction, etc.) during road paving. Warm with construction. When the asphalt concrete composition is divided or transported from the production plant to the construction site, or when the temperature of the asphalt concrete decreases over time during construction in winter cold weather, the composition of the asphalt concrete Hardening is difficult to lay, and poor adhesion between the compaction and the aggregate and the binder results in poor quality of the finished package.

For this reason, the conventional asphalt concrete is flexible enough to secure sufficient workability during construction considering the physical characteristics (temperature sensitivity) of the asphalt (bitumen) as described above and various construction environments to be paved such as seasons or transport distances. You must apply enough heat to get it. However, since the heating of the aggregate in the production of such asphalt concrete composition is usually performed using bunker C oil or light oil as fuel, the combustion of the heating fuel inevitably generated a large amount of CO ₂ gas.

For this reason, CO ₂ Including primary efforts to reduce harmful gas emissions is directed towards lowering the production temperature of the asphalt, when lowering the production temperature of the asphalt concrete has become less use above all oil fuel for heating the aggregates significantly reduce the amount of CO ₂ Besides being able CO ₂ from mixing In addition, the amount of harmful gases generated is reduced, and smoke and odor are also reduced during transportation and installation, thereby making it possible to manufacture low-carbon, eco-friendly asphalt concrete with significantly reduced generation of harmful gases such as CO ₂ .

However, in this case, the lower the production temperature of asphalt concrete, the lower the fluidity and the lower the construction time, so appropriate additives must be used to supplement this.

Various additives are used in the production of domestic and foreign medium-temperature asphalt concrete. Chemical foam, Natrium-aluminum silicate and asphalt fluid additives are mainly used.

Mid-temperature asphalt concrete using chemical foam is mainly used in Japan, and this technique generates bubbles in the asphalt (the same concept as an air entrainer used in some types of cement concrete). It is a technology to maintain the construction year (flexibility) until compaction. However, this technique improves the construction year of asphalt concrete, but may have fine bubbles even after completion of construction, and these fine bubbles may adversely affect the durability of asphalt concrete.

Natrium-aluminum silicate contains about 20% of water, and when mixed with asphalt concrete, water vapor is generated when water is decomposed by asphalt concrete temperature, resulting in foaming action on asphalt due to volume increase. It is mainly studied in Europe as using the effect of improving workability.

In addition, Sasobit wax, which is used in the US as an additive for improving asphalt concrete fluidity, is a hydrocarbon chain additive produced from coal gas through the Fisher-Tropsch process, and has an effect of improving workability and workability at medium temperature. In Korea, PE wax is mainly used instead of sasobit wax.

The above-listed technologies are mostly in the research stage or in the compact car, and the present invention further improves the production of improved medium-temperature asphalt concrete, and further, it is possible to produce low-temperature asphalt concrete below 100 ° C. Relates to low temperature asphalt concrete.

 The present invention is based on the level of asphalt, concrete, flow-resistant asphalt concrete, low noise drainage asphalt concrete, SMA (Stone Mastic Asphalt) asphalt concrete, low noise asphalt concrete, colorless asphalt concrete and recycled asphalt concrete. It is to use, and to prepare asphalt additives that can produce such a large concrete at low and medium temperatures of 80 ℃ ~ 135 ℃ and to produce low-temperature asphalt concrete using the same.

Asphalt concrete is generally produced at 150 ℃ ~ 180 ℃ can secure the fluidity and compactness, and as the production temperature is lowered, the fluidity and compaction also falls. Therefore, in order to manufacture the low-temperature asphalt concrete of 80 ° C ~ 135 ° C aimed by the present invention is required a technology that ensures fluidity, compaction and quality even at this low temperature temperature, by developing a suitable additive Is done.

Additives used for the production of low-temperature asphalt concrete according to the present invention is a ground waste tire of 0.8mm ~ 2mm, vermiculite of less than 3mm and cellulose fibers as the base material. These base materials are added to a primary indirect heating mixer and mixed together with a reforming fluid, which will be melted at a low or medium temperature, and then mixed and heated by adding a particle separator, and then transferred to a secondary cooling mixer for cooling and secondary mixing. Is made through.

Examples of the modified fluid mixed in the base material include at least one of bronze asphalt, EVA (ethylene vinyl acetate), rosin or sulfur as a coating material for promoting adhesion, and SBS (Styrene Butadiene Styrene) as a material for imparting elasticity. It includes any one of SIS (Styrene Isoprene Styrene), urethane, Latex, and EPDM (Ethylene Propylene Diene Monomer), and when rigidity is required, low density polyethylene (LDPE) or high-density polyethylene (HDPE) may be further added thereto. have. The particle separator is calcium carbonate, cement or lime, the heating temperature of the primary indirect heating mixer is 100 ℃ ~ 150 ℃.

The additive according to the present invention is a mixture of EVA or rosin as a predetermined amount of process oil and softener after transferring the mixture obtained through the heat mixing process in the primary indirect heating mixer to the secondary cooling mixer and cooling below 50 ° C. as described above. Is obtained by adding

The additive according to the present invention obtained through the composition and process as described above is added to and mixed with the low-temperature asphalt concrete to serve as a ball-bearing when mixing and laying the asphalt concrete, thereby imparting fluidity to the asphalt concrete even at low and low temperatures. After installation and compaction, there should be no deformation even in solar and large vehicle driving.

The ductility of the asphalt concrete of the present invention is maintained before the compaction, and after compaction, there is no deformation even during the running of the heavy vehicle in the summer, which is composed of a shape close to a circular shape after laying and compacting, which is coated with a reforming fluid. It helps the waste tire to fill the remaining pores of aggregates and gives elasticity to improve the fluidity and improve the thermal resistance of asphalt, prevent plastic deformation, prevent low temperature cracking, and prevent damage of asphalt concrete due to shock absorption. It gives the vermiculite having a porosity composed of fish scales with absorbed and coated reforming fluid to give the fluidity of asphalt concrete and increase the bond strength between aggregate and aggregate as the scale does not fall well after the scale adheres to the object. Because it increases. Vermiculite in the present invention is a mineral belonging to a monoclinic system (VermIculare) having a crystalline structure such as mica, the color is grayish white or brown, pearlescent, expands when heated, and becomes porous. The vermiculite used in the present invention uses the expanded vermiculite by heating, and the expanded expanded vermiculite has a specific gravity of 1 or less, and is made of countless porous materials, so that the reformed fluid is absorbed in the vermiculite during the process of mixing and heating the reformed fluid. And coated, and part of the reforming fluid absorbed and coated by vermiculite when mixed with asphalt concrete flows out and contributes to impart fluidity to the asphalt concrete. As such, vermiculite acts as an attachment medium for adhering between the aggregates by changing the shape of the aggregates between the aggregates and aggregates, unlike the powder of the crushed waste tires filling the voids during the installation and compaction of asphalt concrete. Cellulose fibers coated with a modified fluid absorbent material that increases the strength, unlike the cellulose fibers generally used (cellulose fibers are used to increase the asphalt content in SMA asphalt concrete), the modified fluid is absorbed to give elasticity like a rubber band. It is composed of fine thread, which acts as a reinforcing fiber, increasing tensile strength, shear force, and flexural strength of asphalt concrete.

The present invention is to reduce the production temperature of asphalt concrete to low and medium temperature of 80 ℃ ~ 135 ℃ by reducing the amount of petroleum fuel can reduce the CO ₂ emissions by petroleum fuel and also CO ₂ and other generated during the mixing, transportation, packaging process It is possible to manufacture eco-friendly asphalt concrete by reducing the amount of harmful air pollutants, and can be constructed at a low temperature, which will have another feature of shortening the quality stability and traffic control time.

 Particularly, crushed waste tires, vermiculite, and cellulose fibers play a role of quality improvement material as fluidization plays a role as a quality improvement material. As a result, not only asphalt concrete but also colored asphalt concrete using SMA, low noise and colorless asphalt, as well as modified asphalt concrete, recycled asphalt It has secured quality that can be applied to a variety of concrete.

1 is a material configuration diagram of an additive according to the present invention.
Figure 2 is an enlarged view of the modifying additives distributed in the low-temperature asphalt concrete according to the present invention.

In the first indirect heating mixer, 100 parts by weight of crushed waste tires crushed from 2 mm to 0.08 mm in size, 10 to 200 parts by weight of vermiculite having a specific gravity of 1.0 mm or less and a size of 3 mm or less with heat expansion and micropores, cellulose fibers 1-10 parts by weight of asphalt or EVA to promote adhesion, 1 of rosin, rosin, PE WAX, EVA WAX to promote flow, as a component of the reforming fluid while heating by adding 10 to 200 parts by weight. 1 ~ 30 parts by weight of more than 1 part and 1 ~ 100 parts by weight of SBS, SIS, urethane, latex, EPDM are added to increase the elasticity, and LDPE or HDPE should be added to increase rigidity if necessary. It can add -100 weight part more.

In this mixture, 1 to 30 parts by weight of one or more of calcium carbonate, cement or slaked lime are selected as the particle adhesion preventing material to prevent the adhesion of the crushed waste tires, vermiculite and cellulose fibers to each other. It heats and mixes so that temperature may become 100 degreeC-150 degreeC.

The heated and mixed mixture is cooled to 50 ° C. or lower by opening the gate of the first indirect heating mixer, transferring the resultant to a screw conveyor, and then mixing the mixture into an air-cooled or water-cooled secondary cooling mixer.

The cooling process through the secondary cooling mixer is to facilitate the handling such as packing the additives according to the present invention in a plastic bag or the like and injecting them into asphalt concrete. In this cooling process, the above-described reforming fluid and particle adhesion preventing material are used. 5 ~ 300 parts by weight of process oil to improve the mixing performance of coated crushed waste tires, vermiculite and cellulose fibers with asphalt concrete, and rosin of less than 5mm or less than 4mm to improve adhesion and better fluidity. Add 10-100 parts by weight of EVA. Determining the size of these particles is because when they are out of the size of the particles, they are not completely melted in the process of mixing the asphalt concrete at low to low temperatures, and thus soften at 50 ° C to 80 ° C in low temperature asphalt concrete at 80 ° C to 100 ° C. Using that. In medium temperature asphalt concrete at 100 ℃ ~ 135 ℃, softening at 50 ℃ ~ 100 ℃ is used.

The amount of the process oil used 5 ~ 300 parts by weight depending on the product use, such as whether to use additives for the production of new asphalt concrete or recycled asphalt concrete, the amount of use is variable, it is added to new asphalt concrete It is used more when it is added to recycled asphalt concrete (20 to 300 parts by weight) than when it is (5 to 20 parts by weight). In the case of new asphalt concrete, there is no use effect when the process oil is used at 5 parts by weight or less. Above 20 parts by weight, the asphalt concrete is too soft and there is a risk of plastic deformation.In the case of recycled asphalt concrete, the use effect is less than 20 parts by weight. No more than 300 parts by weight is softened severely, the use effect is low. Here, the process oil is paraffin-based, naphthenic-based, aromatic based.

The low-temperature vinyl is melted at low temperature by transporting and weighing the low-temperature asphalt concrete additive obtained through the first and second mixing processes in which high temperature heating, mixing, coating and low temperature process oil and EVA or rosin are added. After packing in, the packaged additive is used as a plant input type.

Additive according to the present invention is 40mm, 25mm, 19mm, 13mm coarse asphalt concrete, 19mm, 13mm flow resistant asphalt concrete, 19mm, 13mm, 10mm, 8mm, 5mm low noise and drainage asphalt concrete, 13mm, 10mm, 8mm SMA asphalt concrete, It is used for color asphalt concrete using 13mm, 10mm low noise asphalt concrete, recycled asphalt concrete, and colorless asphalt, and 100 parts by weight of aggregate used for asphalt concrete is heated to 80 ℃ ~ 135 ℃, which is a low temperature, and calcium carbonate, calcined lime, etc. Filler 2 to 12 parts by weight and 4 to 8 parts by weight of asphalt heated to 120 ℃ ~ 170 ℃ mixed into the mixer, this is 0.2 to 1.5 parts by weight of additives according to the present invention (in general asphalt concrete production) or 1.5 to 2.5 Used by weight part (when producing low noise asphalt concrete).

In the present invention, the heating temperature of the aggregate is set at 80 ° C. to 135 ° C., which is mid-low temperature, and 80 ° C. or less may cause plastic deformation due to solar heat in summer. to be.

The primary and secondary mixers are divided into primary and secondary mixers for the purpose of heating, and secondary mixers are used to lower the temperature of the heated additives to improve product handling. As described above, the crushed waste tires, vermiculite, and cellulose fibers are the basic materials for the low and medium-temperature asphalt concrete additives, and the crushed waste tires are circular in shape and do not melt at the temperature of the asphalt concrete of 80 ° C to 135 ° C. It maintains its shape to fill the remaining pores of aggregates to give elasticity and to improve plastic deformation resistance, increase resistance to low temperature cracking, and to improve temperature sensitivity. Vermiculite is heated and expanded so that the specific gravity of porosity is 1 or less. In addition, the modified fluid for improving strength is absorbed and coated, and then flows by the temperature when mixed with asphalt concrete to be mixed with the asphalt concrete, contributing to the medium-lower temperature of the asphalt concrete (to secure construction properties at low and medium temperatures). Vermiculite is light and porous, and is composed of fish scales and has the shape of absorbing impact.It is mixed with asphalt concrete, and it is effective because less than 10 parts by weight is used to improve the adhesion of aggregate and aggregate during compaction after installation. And 200 parts by weight or more is more than twice as much as the amount of the crushed waste tires, which reduces the effect of crushed waste tires.

In the present invention, the cellulose fiber is coated with a reforming fluid, etc., thereby acting as a reinforcing fiber without compromising the fluidity of the asphalt concrete, thereby further combining the aggregate and the aggregate to enhance the tensile strength and adhesion strength of the asphalt concrete.

Therefore, the pulverized waste tire is composed in a circular shape, vermiculite is composed of scales, and cellulose fibers are composed of fine yarns, and each plays a different role. These three elements fill the voids of the aggregate and aggregate in the asphalt concrete. It plays a role of elasticity, strengthens adhesion between aggregate and aggregate, and strengthens cohesion between aggregate and aggregate. It has excellent fluidity at low and low temperatures before compaction, and also inter-aggregate particles after compaction. In this state, even when a heavy vehicle passes, the vehicle is strongly coupled without being disturbed, thereby making it extremely durable.

The reason for heating the pulverized waste tires, vermiculite and cellulose fibers by indirect heat in the present invention is that when the direct heat is applied, the pulverized waste tires and cellulose fibers may be incinerated. The indirect heating temperature is set at 100 ° C. to 150 ° C. because the modified fluid added thereto is not completely melted at 100 ° C. or lower, and is bonded between particles at 150 ° C. or higher. In the present invention, the pulverized waste tire should maintain particle development.

In the present invention, as one component of the reforming fluid, one or more of bronze asphalt or EVA is used as a coating material for promoting adhesion, and the bronze asphalt is packaged as a solid, which is convenient to use, has high asphaltene content, and low penetration. EVA can enhance adhesion. The use amount is 1 to 30 parts by weight because the use effect is inferior when it is 1 part by weight or less, and when it is 30 parts by weight or more, particles such as crushed waste tires stick together and cannot serve as unit particles.

In addition, in order to increase the fluidity as another component of the reforming fluid in the present invention, one or more selected from rosin, sulfur, PE WAX, EVA WAX is used, rosin and the like is rigid at room temperature, the flowability when heated It gives good flow resistance to asphalt and makes asphalt concrete stabilized at room temperature.

 1 to 30 parts by weight of such rosin, etc., 1 part by weight or less has no use effect and 30 parts by weight to adhere between particles such as crushed waste tires.

In addition, in the present invention, in order to impart elasticity as another component of the reforming fluid, at least one of SBS, SIS, urethane, latex, and EPDM or 1 to 100 parts by weight of LDPE or HDPE is used to increase the strength as necessary. When the material is heated to 100 ℃ ~ 150 ℃, some are melted but some are in the form of particles, so the size of the particles is limited to fine powder ~ 2mm in order to make sufficient melt state. More than the weight part is used excessively, and makes particles of crushed waste tires and the like stick.

In the present invention, the use of calcium carbonate or the like as a particle separation material such as crushed waste tires has an effect of less than 1 part by weight, and more than 30 parts by weight is excessively used, affecting quality and dusting.

(Example 1)

 Low-temperature asphalt concrete additives (kg) 1. Primary mixer (indirect heating mixer) A Type B type C type  Grinding Waste Tire (40 Mesh or Less) 800 800 800 Vermiculite (2mm or less, specific gravity 0.5) 150 150 150 Cellulose island oil 150 150 150 -Heating Indirect heat while heating up to 80 ℃
Input materials such as coating materials Bron Asphalt 25 25 25 Rosin 50 50 50 E V A 25 25 25 S B S 100 150 250 Calcium Carbonate 100 100 100 -Heating Indirect heat heated up to 140 ° C (about 2 hours) 2. Secondary cooling mixer injection A B C - Cooling Cool 45 ℃ with coolant circulation mixer Proces oil 60 60 60 E V A (3mm or less) 200 300 400 Grinding rosin [Rosin] (less than 3mm) 300 300 300 3. Total 1960 2110 2310

Medium and low temperature modified asphalt (asphalt used AP-5 (infiltration degree 60-70)) type A B C Medium and low temperature additive 5.5kg 6.0kg 9.0 kg AP-5 52 kg 58 kg 51 kg Penetration Degree (25 ℃) 52 49 44 PG rating 76-22 76-22 82-22

(Example 2)

Modified asphalt concrete using additives A, B and C of Example 1

A Type: Compactness Modified Asphalt Concrete 19mm (WC-3)

 Mixture production temperature: 110 ℃

Particle size distribution Size
(mm)  Sieve Weight Percentage (%) 25 20 13 10 5 2.5 0.6 0.3 0.15 0.08 Granularity 100 92.0 81.5 70.7 55.0 40.2 20.4 15.6 10.2 6.0 standard 100 90-100 72-90 56-80 35-65 23-44 10-28 5-19 3-13 2-8

Compounding ratio (unit: kg) Material Name AP-5 Aggregate Filler
(Calcium Carbonate) Low to low temperature
additive system Material amount (kg) 52.0 902.5 40.0 5.5 1000.0

 B Type: Flow Resistant Asphalt Concrete 13mm (WC-6)

  Mixture production temperature: 120 ℃

Particle size distribution Size
(mm) Sieve Weight Percentage (%) 20 13 10 5 2.5 0.6 0.3 0.15 0.08 Granularity 100 92.0 81.6 51.4 33.6 17.4 13.8 7.2 6.9 standard 100 90-100 73-90 40-60 25-40 11-22 7-16 4-12 3-9

Compounding ratio (unit: kg) Material Name AP-5 Aggregate Filler
(Calcium Carbonate) additive system Material amount (kg) 58.0 896.0 40.0 6.0 1000.0

C Type: Low Noise Drainage Modified Asphalt Concrete 13mm

Mixture production temperature: 120 ℃

Particle size distribution Size
(mm) Sieve Weight Percentage (%) 20 13 10 5 2.5 0.6 0.3 0.15 0.08 Granularity 100 100 72.0 18.9 15.4 9.1 6.7 5.6 5.2 standard 100 92-100 62-81 10-31 10-21 4-17 3-12 3-8 2-7

Compounding ratio (unit kg) Material Name AP-5 Aggregate Filler
(Calcium Carbonate) additive system Material amount (kg) 51.0 890.0 50.0 9.0 1000.0

quality division AType BType CType standard Production temperature (℃) 110 120 120 80-135 Marshall stability (kg) 1001 1092 840 Over 750 Frow (1 / 100m) 35 30 29 20-40 Residual tensile strength ratio after immersion (%) 82 84 90 75 or more Porosity (%) Particles and Flow Resistance 1.5 4.2 - 3-5 Low noise and drainage - - 20.5 18 or more Permeability Factor (cm / sec) - - 5.5 x 1 x or more Saturation degree (%) 78 82 80 75-85 Dynamic stability (times / mm) 5890 7290 4200 3000 or more

none

Claims (4)

In the first indirect heating mixer, 100 parts by weight of pulverized waste tires crushed into 2 mm to 0.08 mm in size, 10 to 200 parts by weight of vermiculite having a specific gravity of 1.0 mm or less and a size of 3 mm or less, heat-expanded, and cellulose fibers 10 to 200 1 to 30 parts by weight and SBS selected from bronze asphalt or EVA 1 to 30 parts by weight, rosin, sulfur, PE WAX and EVA WAX as the components of the reforming fluid while mixing by weight 1 to 100 parts by weight of at least one selected from SIS, urethane, latex, and EPDM are mixed and heated to obtain a temperature of 100 ° C. to 150 ° C. in the mixer. Selecting at least one of calcium carbonate, cement or lime as an additional 1 to 30 parts by weight of the first step of mixing; And
The mixture according to the first step is introduced into an air-cooled or water-cooled secondary cooling mixer and cooled to 50 ° C. or less, while process oil is 5 to 300 parts by weight, rosin (5 mm or less), or EVA 10 (4 mm or less). A second step of adding -100 parts by weight;
Modified additive for producing low-temperature asphalt concrete, characterized in that it is produced, including In claim 1,
Modified additive of low-temperature asphalt concrete, characterized in that at least one of LDPE or HDPE 1 ~ 100 parts by weight is added to the first step is mixed. In claim 2,
The rosin of 5 mm or less or EVA of 4 mm or less is softened at 50 ° C. to 80 ° C. when the additive is used to manufacture low temperature asphalt concrete at 80 ° C. to 100 ° C., and medium temperature asphalt concrete of 100 ° C. to 135 ° C. Modified additives for low-temperature asphalt concrete, characterized in that when used in the manufacture is softened at 50 ℃ ~ 100 ℃ 100 parts by weight of aggregate heated to 80 ° C to 135 ° C for asphalt concrete, 2 to 12 parts by weight of filler selected from any one or more of calcium carbonate, slaked lime or cement, and 4 to 8 parts of asphalt heated to 120 ° C to 170 ° C. Medium and low temperature of 80 ℃ to 135 ℃ by mixing 0.2 ~ 1.5 parts by weight (in general asphalt concrete production) or 1.5 ~ 2.5 parts by weight (in the production of low noise asphalt concrete) and the additive according to any one of claims 1 to 3. Asphalt concrete produced by.

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