KR20190121268A - Method of manufacturing recycled aggregate and normal temperature ascon manufactured by using the same - Google Patents

Abstract

The present invention relates to a manufacturing method of a recycled aggregate for room temperature ascon, which comprises the steps of: preparing a product to be crushed for the recycled aggregate by crushing concrete waste and performing size selection; washing the product to be crushed; and sequentially stacking in the product to be crushed of a washed wet state on a conveyor belt equipped with a plurality of far-infrared heaters, and drying and conveying the same. Because the moisture content of the recycled aggregate dried by the method can be adjusted, physical properties compared to ascon using new aggregates are further improved, while lowering the unit cost of the ascon manufactured using the same.

Description

Manufacturing method of recycled aggregate and room temperature ascone manufactured using the same {METHOD OF MANUFACTURING RECYCLED AGGREGATE AND NORMAL TEMPERATURE ASCON MANUFACTURED BY USING THE SAME}

The present technology is a technology in the field of ascon production, and more specifically, it is possible to easily produce recycled aggregates by adopting a new method for drying waste aggregate crushed products. The present invention relates to a technology capable of producing ascon having more excellent physical properties.

The conventional road repairing method is a process of mixing and heating the bitumen mixture according to the KS F 2349 method, and the mixture is heated and dried at a high temperature of 170 to 180 ° C. with crushed stone, gravel and fine aggregates and then to 140 to 150 in this dry matter. An appropriate amount of straight asphalt heated to 0 ° C. is added as a binder and a high temperature ascon mixed with these at high temperature. However, the high temperature ascon prepared by this method is rapidly increased in viscosity due to the characteristics of the asphalt, the viscosity of the binder becomes agglomerate, and in order to prevent this, it is inconvenient to maintain the bitumen mixture at 130-140 ° C. and to pack it within a limited time. It is also difficult to transport long distances, and there is a risk of material separation during winter construction. In particular, there is a problem that it is difficult to use a large unit of asphalt when the road damage is small. In order to solve various problems that occur when the high temperature ascon (also referred to as a heated ascon) for road repair as mentioned above, a room temperature ascon which is capable of mixing at room temperature and laying at room temperature has been proposed.

Ascon is shortened asphalt concrete and is generally used to heat asphalt and coarse aggregate (gravel), fine aggregate (sand) or pavement material (filler, mineral filler). They are mixed at room temperature and are mainly used for road pavement or parking lot, and are classified into various types according to the purpose of use, use, function, and construction method.

On the other hand, recycled aggregates are also used as aggregates used in room temperature ascon. In order to produce recycled aggregates, the waste aggregates must be washed and dried. Conventionally, a drum drying method has been used for the drying. This method puts the waste aggregate washed in a large drum dryer and batch drying. However, such drum drying requires a large installation cost and a large installation cost. In addition, this method is a heavy burden for the material separation because the size separation must proceed for a large amount of waste aggregate.

Furthermore, the drum method has a problem in that it is difficult to control the degree of drying of the waste aggregate, and uniform drying is difficult.

The present invention is derived to overcome the problems of the conventional drum-type drying process, it is easy to separate the size of the waste aggregate, can easily control the degree of drying according to the intention of the operator and dust blowing that can occur during drying An object of the present invention is to provide a method for producing a recycled aggregate for room temperature ascone can be prevented.

In addition, an object of the present invention is to provide a room temperature ascon more improved physical properties compared to ascon using new aggregates, including the recycled aggregate prepared as described above.

Method for producing a recycled aggregate for room temperature asphalt concrete according to an embodiment of the present invention comprises the steps of preparing a crushed aggregate for crushing the concrete waste and screening the size; Washing the debris; And drying the washed wet debris while being sequentially loaded and transported on a conveyor belt equipped with a plurality of far infrared heaters.

The crushed material is preferably selected to a size of 8mm or less.

The loaded debris can be uniformly dried by mixing by means of a plurality of mixers of different sizes in the form of rotarys disposed on the conveyor belt.

A heat reflector and a temperature sensor are provided on the conveyor belt.

The drying is such that the temperature of the recycled aggregate is a temperature of 40 to 50 ℃ by adjusting the calorific value of the far infrared heater. On the other hand, the drying is made so that moisture remains in the dried recycled aggregate.

The far infrared heater is a heater that generates heat using LPG gas or electricity.

Room temperature ascon according to an embodiment of the present invention 50 to 90% by weight recycled aggregate having a size of 8mm or less prepared in the above-described manner; 10 to 50% by weight of new aggregate having a size of 4 to 8mm; 4 to 10% by weight of unheated asphalt as a binder; And 0.04 to 1.5% by weight of dimer acid as the anti-peeling agent.

Since the method for producing recycled aggregate according to the present invention uses waste concrete crushed material, it can be recycled to functional components such as various fillers mixed with waste concrete in addition to the aggregate component. Therefore, the present method can exclude a large number of mixing elements among the mixed components used in the ascon mixing process, it is possible to save the material used in the ascon mixing process as well as to reduce the manufacturing cost using recycled aggregate is very economical.

In addition, the manufacturing method of the recycled aggregate is a method for drying the washed and wet concrete crushed material, it is introduced by a method of drying using a conveyor belt equipped with a far-infrared heater instead of the conventional drum method, continuous drying It is possible to separate materials such as size selection. Since the far-infrared heater is driven using LPG gas, no wind is generated and dust blowing, which may occur during the drying process, may be prevented. In the present embodiment, the far-infrared heater is described as using LPG gas as a heat generating source. Alternatively, the far-infrared heater using electricity may be used.

On the other hand, on the conveyor belt it is possible to uniformly dry or crush the waste aggregate crushed to be continuously and evenly rolled small and large mixers of the rotary form continuously to be dried.

In addition, a temperature sensor is provided on the conveyor belt, so that the drying temperature of the crushed material can be adjusted to a desired temperature, and further, the amount of moisture remaining in the crushed material can be adjusted.

Ascon of the present invention is a room temperature ascone, because the above-mentioned recycled aggregate is used, and the recycled aggregate retains moisture, and thus has excellent strength as the components of concrete, which are the main components of the recycled aggregate, are further collected when compacted in response to moisture. In addition, the ascon mixing process is simple and economically effective by mixing only non-heated asphalt and dimer acid with recycled aggregates and other new aggregates without using a separate filler when mixing the ascon.

On the other hand, when the appropriate amount of water is included in the concrete crushing to form the recycled aggregate, by preventing the penetration of the material in the ascon mixture during storage before the construction of room temperature ascon, the aggregate is not hardened. In other words, the moisture in the recycled aggregate serves as a protective means to prevent the penetration of the solvent, through which can significantly increase the storage and work stability of ascon.

Room temperature ascon of the present invention may exhibit superior physical properties compared to existing products using new aggregates in terms of physical properties such as stability, flow value, immersion residue stability. As a result, according to the present invention, it is expected that the unit cost of the room temperature ascon can be lowered and the physical properties can be maximized, thereby significantly improving the economics of the ascon field in the future.

1 is a conceptual diagram conceptually showing a recycled aggregate drying apparatus used in the drying step of the waste concrete crushed material according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings, it will be described in detail a method for producing a recycled aggregate in one embodiment of the present invention. However, the following description is only for the conceptual understanding of the present invention is not limited by the following description. The spirit of the present invention may be interpreted or limited only by the following claims.

The method for producing recycled aggregates according to an embodiment of the present invention uses waste concrete as recycled aggregates. Since waste concrete contains useful components such as various fillers included in concrete and binders included in concrete mixtures as well as aggregate components, when waste concrete is used as aggregate, there is an advantage that it can be utilized when mixing ascon to functional components. .

In order to produce recycled aggregate, first, the waste concrete is crushed. The crushed waste concrete crushed is screened to have a size of 8 mm or less by screening the particles by various sorting methods known first. The screened debris is then washed to remove debris. Thus, the crushed waste product maintains the wet ecology. Thereafter, the wet debris is subjected to a drying step.

1 is a conceptual diagram conceptually showing a recycled aggregate drying apparatus used in the drying step of the waste concrete crushed material according to an embodiment of the present invention. Referring to Figure 1, it will be described in detail the drying step of the main process of the present invention.

Referring to FIG. 1, the washed waste concrete crushed material 5 is placed in a small hopper (not shown) to minimize material separation, and is then supplied to the recycled aggregate drying apparatus 1000 to start the drying process simultaneously with the transfer. The crushed material 5 is transported along the conveyor belt 50 and dried.

The recycled aggregate drying apparatus 1000 includes a plurality of far infrared heaters 400. The far infrared heater 400 is sequentially disposed on the conveyor belt 50. The far infrared heater 400 may heat the crushed material 5 to about 150 ℃ or more. In this embodiment, the far-infrared heater 400 is driven by LPG gas as fuel, the recycle aggregate drying apparatus 1000 includes an LPG tank 110 for this purpose. LPG tank 110 is interlocked with the blower 120, the LPG gas is supplied to the far infrared heater 400 through the conduit (300). The far-infrared heater 400 does not cause wind and does not cause dust or the like in the drying process by applying radiant heat to the crushed material 5. The far infrared heater 400 may be periodically spaced apart from the predetermined interval in the moving section of the conveyor belt (50). On the other hand, the far-infrared heater 400 may be controlled by adjusting the amount of supply of gas, thereby adjusting the drying level of the crushed material (5).

Blower 120 is connected to a control box 220 that can control the flow rate and speed of the LPG gas, the control box 220 is a shredded material (5) measured from the temperature sensor 700 shown in FIG. In order to control the flow rate and speed of the LPG gas by inputting the temperature of) and ultimately, the temperature of the crushed material 5 itself can be adjusted according to the intention of the operator. The control box 220 is driven by receiving power from the power source 210.

The crushed material 5 transferred to the conveyor belt 50 is continuously supplied to the wetted state by the far-infrared heater 400 while moving to the wet state and dried to the inside of the crushed material 5 particles. In addition, the crushed material 5 may be uniformly dried as a whole by being evenly spread or rolled by the mixers 510 and 520 in the process of being transported on the conveyor belt 50. That is, it is necessary to be managed so that the moisture content of each of the shreds 5 is not significantly different due to irregular drying. The mixers 510, 520 include a large mixer 510 and a small mixer 520. Therefore, it is possible to evenly mix the particles of the crushed material 5 having a distribution of fine powder ~ 8 mm or less. The mixers 510 and 520 are rotary type mixers and may have a gear shape or a bolt shape.

When measuring the temperature by the temperature sensor 700 after passing through the far infrared heater 400 while moving the conveyor belt 50, the temperature of the crushed material 5 itself is accurately measured by the hot air heated by radiant heat. There is a difficult side. Therefore, the recycled aggregate drying apparatus includes a heat reflector 600 to pass through the heat reflector 600 before the crushed material 5 reaches the temperature sensor 700. The heat reflector 600 serves to allow the shredder 5 to continuously reflect the heat of the shredder 5 itself while passing through the heat reflector 600. Therefore, the temperature sensor 700 can then substantially measure the drying temperature of the shreds 5 itself by measuring the temperature of the air in equilibrium with the heat of the shreds 5 itself.

It is preferable that the temperature of the dry crushed material 5 is maintained at 40-50 degreeC. The residual moisture content of the dried crushed material 5 dried at such a temperature condition may act as a key factor in maximizing the workability and the properties of ascone in the subsequent ascon mixing process.

That is, the recycled aggregate drying apparatus 1000 is an apparatus that not only dries the crushed material 5 effectively but also ultimately controls the water content in the crushed material 5 to thereby have an important influence on the production process of ascon and the physical properties of the produced ascon. do.

The recycled aggregate thus prepared is used for ascon mixing. Ascon according to the present invention is a room temperature ascon, usually a room temperature ascon is a composition comprising an aggregate, a filler, a binder and a peeling inhibitor.

However, the room temperature ascon according to the present invention may be excluded from the filling material in the mixing process. This is because waste concrete itself, which forms the recycled aggregate, already contains components such as filler. In addition, since components such as various binders blended in the concrete mixing process remain in the recycled aggregate, additives in the ascon mixing process can be minimized.

Room temperature ascone according to an embodiment of the present invention, recycled aggregate, new aggregate, non-heated asphalt as a binder and only dimer acid as a peeling preventive agent and does not include a separate additive or functional agent. Specifically, the room temperature ascon is 50 to 90% by weight of the recycled aggregate having a size of 8 mm or less prepared as described above; 10 to 50% by weight of new aggregate having a size of 4 to 8mm; 4-10% by weight of unheated asphalt; And 0.04 to 1.5% by weight of dimer acid.

If the asphalt is a non-heated asphalt, the type and shape thereof are not particularly limited, and examples thereof include straight asphalt, cutback asphalt, emulsified asphalt, and modified asphalt. Modified asphalt is to improve the asphalt physical properties for the purpose of improving the durability, flow resistance, wear resistance, slip resistance, etc. of the asphalt pavement, rubber, such as SBS, SBR or plastics such as polyethylene, polypropylene is usually added. As a binder of one component of room temperature ascon according to the present invention, it is preferable that the cutback asphalt. Asphalt cement used for road paving is semisolid at room temperature, so it must be heated and melted when mixed with other aggregates or sprayed on road surfaces. To reduce this inconvenience, cutback asphalt is made by mixing asphalt cement with a volatile petroleum solvent in a liquid state. Cutback asphalt is evaporated, dried, and cured at different speeds depending on which solvent is mixed. Rapid cut asphalt is classified into rapid curing (RC), medium curing (MC), and slow curing (SC). Rapid curing type uses gasoline to reduce viscosity and improve fluidity. Medium-speed curing type is produced by using kerosene to slow the evaporation rate, and slow curing type refers to using heavy oil such as diesel.

Cutback asphalt used as a binder in room temperature asphalt concrete is a good viscosity to improve the fluidity by adding a suitable volatile solvent, that is, diluent oil, to straight asphalt having a penetration of 60 to 150, and the dilution oil content is about 10 to 45 Weight percent. KSM2202, the standard for cutback asphalt, classifies products by classifying rapid curing cutback asphalt into 6 grades (RC-0 to RC-5) according to the degree of viscosity. Examples of binders for road-flood mixing, binders for room-temperature repair construction as open-end aggregates, binders for room-temperature laying construction as open-end aggregates, and binders for room-mix laying under cold climatic conditions. In addition, KSM2202, a cutback asphalt standard, classifies products by classifying medium-speed hardened cutback asphalt into six grades (MC-0 to MC-5) according to the degree of viscosity. Binders for road-mixing works as aggregates, Binders for room-temperature repair works as pavement aggregates, Primings, Binders for road-mixing works as aggregates, Binders for room-temperature repair work mixtures as aggregates, and at room temperature Illustrates binders for construction machinery mixing. Cutback asphalt used as a binder as a component of room temperature ascon according to the present invention, depending on the application (as well as road pavement or catcher, sidewalk pavement or repair, tunnel pavement or repair, surface layer, intermediate layer, base layer, etc.) It can be freely selected and used.

As said peeling inhibitor, even in the case of this invention, even if it uses dimer acid alone, there is no physical property fall at all. The dimer acid improves the adhesion of asphalt when the aggregate surface of the asphalt is wet and at the same time prevents the asphalt from being peeled off by the action of external force or rain as a component to increase the resistance of ascon.

Table 1 shows the composition of room temperature ascone according to an embodiment of the present invention. The aggregate used in the asphalt concrete is a mixed aggregate having a new aggregate having a particle distribution of 4 to 8 mm and a recycled aggregate having a particle size distribution of 8 mm or less (satisfactory KSF2357 fine aggregate particle size) in a weight ratio of 4: 6. In addition, the aggregate used described the content ratio according to the particle distribution.

8-5mm 5 ~ 2.5mm 2.5 ~
1.2 mm 1.2 ~
0.6mm 0.6 ~
0.3mm 0.3 ~
0.15mm 0.15 ~
0.08mm 0.08mm
Below cutback
asphalt Dimer Mountain 5-20% 40-70% 5-20% 3 ~ 10% 1-5% 1-5% 1-5% 1-5% 4-10% 0.04-
1.5%

Property evaluation

Table 2 is a table showing the results of the physical property test (based on KSF2369) for the conventional products (Dahyun Industry) and the Ascon products manufactured with the composition of Table 1 using the new novel aggregate.

division Applicant Existing Product Recycled Aggregate Used Products Stability (N) 3,000 5,500 Flow value (1 / 10mm) 27 30 Immersion Residual Stability (%) 80% 98%

Referring to Table 2, the components of the concrete, the main component of the recycled aggregates reacts to moisture and is further collected when compacted to measure excellent strength. The stability was more than 70% compared to the existing product, and the stability of immersion residue was also more than 95%.

Claims (5)

Crushing concrete waste and screening the size to prepare shredded material for recycled aggregate;
Washing the debris; And
In order to increase the cohesiveness when compacting concrete and to form a protective means for preventing the penetration of the solvent in the ascon mixture when storing the room temperature ascon, the washed wet crushed matter is placed on a conveyor belt equipped with a plurality of far infrared heaters. Controlling moisture while loading and transporting sequentially; Including,
Method for producing recycled aggregate for room temperature ascon.
The method of claim 1,
The crushed product is a method for producing a recycled aggregate for room temperature ascon characterized in that the screening is selected in size less than 8mm.
The method of claim 1,
Method for producing a recycled aggregate for room temperature ascone, characterized in that for controlling the calorific value of the far-infrared heater so that the temperature of the dried recycled aggregate is 40 to 50 ℃. i) crushing the concrete waste and screening the size to prepare shreds for recycled aggregate; Washing the debris; ii) to maintain the wet wet shreds at a temperature of 40-50 ° C. in order to increase the cohesiveness when compacting concrete and to form a protective means for preventing the penetration of solvent in the ascon mixture when storing the room temperature ascon Controlling moisture of the crushed product while sequentially loading and transporting the conveyor belt equipped with a plurality of far infrared heaters so as to transfer the same; And iii) the step of producing a recycled aggregate for room temperature ascon including the step of selecting the particle size of the crushed to 8mm or less; And
Method for producing a room temperature ascon characterized in that it comprises the step of mixing the aggregate and the new aggregate having a particle size distribution of 4 to 8mm.
Prepared by the method of claim 4,
Room temperature ascon characterized in that it has a stability (N) of 5,500, a flow value of 30 (1 / 10mm) and a immersion residual stability of 98%.

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