KR101087402B1 - Parallel Flow Changeable Tilt Drum-Mixer in Hot Mix Asphalt Plant - Google Patents

Abstract

The present invention is a parallel flow type drum mixer for the production of regenerated heating asphalt, wherein the support frame for rotating the drum mixer is separated from the main frame located below, the support frame and the main frame on the discharge chute side of the drum mixer Regenerative heating asphalt mixture, characterized in that the inclination of the drum mixer relative to the main frame is adjusted in the range of -6 ° ~ + 6 ° by the inclination adjusting device consisting of a cylinder coupled to the hinge shaft and the new aggregate inlet side It relates to a tilt control parallel flow drum mixer for production.

Drum Mixer, Parallel Flow Drum Mixer, Tilt Control, Backflow Veil

Description

Parallel Flow Changeable Tilt Drum-Mixer in Hot Mix Asphalt Plant

The present invention relates to a parallel flow-type drum mixer for the production of regenerated heating asphalt mixture, in detail, the cylindrical drum mixer is configured to be inclined in the range of-6 ° to + 6 ° to shorten the preheating time of the drum mixer and start operation It solves the problem of incomplete drying and heating of asphalt mixture, and it is possible to effectively obtain the optimum discharge temperature of asphalt mixture according to the mixing ratio or characteristics of new aggregate and circulating aggregate, and to minimize the difference between the temperature of the asphalt mixture and the exhaust gas temperature. It improves combustion efficiency, and forms a counter-current bale section before the cycle aggregate input for asphalt concrete in the drum of the cylindrical drum mixer, so that repeated heating of the new aggregate is performed within the section, and the flame is prevented from directly acting on the recycled aggregate. Prevents premature aging of asphalt cement (Asphalt Cement, AC, hereinafter AC) Reclining parallel-flow for reproducing a heated asphalt mixtures relates to a drum mixer.

As most roads, runways, etc. are made of heated asphalt pavement, the demand for heated asphalt mixtures is increasing.As such, asphalt concrete generating material (hereinafter ascon) is used during the dismantling of pavement, excavation for underground laying, and cutting and overlaying. Emissions) are increasing.

Ascon generating materials were conventionally treated as waste and used as subsidiary materials for road construction or road construction, but the quality standards for base and surface asphalt concrete have been improved by developing and improving the recycling technology of ascon generating materials and mixing them with new asphalt concrete in an appropriate ratio. It was met. As a result, the Act on the Promotion of Recycling of Construction Wastes was enacted, and the ratio of the use of Reclaimed Asphalt Pavement (RAP) for asphalt concrete was up to 50% or less in the case of a base-heat regenerated asphalt mixture. In case of surface use, it can be used up to 30% or less, and the Ministry of Land, Transport and Maritime Affairs enacted the `` Circulation Aggregate Quality Standard '' to classify ascon generating materials in two stages of 20 ~ 13mm and 13mm or less so that they can be used as RAP. Some local governments, such as Seoul Metropolitan Government, have mandated the use of more than 10% of RAP for a certain scale of construction through the ordinance, but the site is neglected due to the prejudice of recycled materials and the lack of quality control that satisfies the commonality of packaging. to be.

Heated asphalt packing consists of a series of processes that continuously produce heated asphalt mixtures by plants, field transport of heated asphalt mixtures by trucks, dropping the faders, laying them by paper, and compacting by rollers. Therefore, the commonness of heated asphalt pavement is influenced by various factors such as structural design of paving layer, asphalt mix design, mixture production, laying, compaction process, construction capacity and quality, etc. Pavement irregularities on the surface of the pavement, cracks on the line, tissue irregularities, screed marks, screed reaction defects, shadowing, compaction, cracks, jungle and plastic deformation, bleeding, roller marks, material separation, etc. It causes early fatigue and inhibits long-term commonality of asphalt pavement.

Packaging with regenerated heated asphalt mixtures is designed and constructed in accordance with `` Asphalt Pavement Design and Construction Instructions '' and `` Road Construction Standard Specification '' as with new heated asphalt mixtures. The problem associated with the production of hot asphalt mixtures, namely the moisture content of the aggregate before it is coated with asphalt cement (AC), the optimum discharge temperature of the asphalt mixture, the quality of the RAP and the AC It is associated with premature aging phenomena caused by direct contact with heat.

In the regenerated heated asphalt mixture produced by mixing RAP, if the RAP does not meet the circulating aggregate quality standard, or the content is too high or high in water content compared to the new aggregate, the aggregate is not sufficiently dried during the production of the heated asphalt mixture. After peeling off, rolling and plastic deformation occur after construction, and excessive absorption of asphalt mixture causes bleeding and spots or stains on the asphalt surface.

In addition, the asphalt mixture is discharged at a lower temperature than the proper discharge temperature, which causes premature hardening in the transportation construction process, and the RAP and AC are in direct contact with high temperature heat to promote the early aging of AC as well as the generation of hydrocarbon gas. It will compromise long-term utility.

In addition, drum mixers dry and heat aggregates with burner flames, and mixing of recycled additives such as RAP and AC is the main process, so that RAP and AC are ignited when they are in direct contact with flame and high temperature heat, and hydrocarbons represented by blue smoke. And the consumption of a lot of fuel causes a problem that the efficiency of the burner is reduced.

The parallel flow drum mixer is a drum mixer structure in which the exhaust gas flow direction of the burner on the drum end and the flow direction of the new aggregate and the RAP are parallel in a plant for producing a heated asphalt mixture or a regenerated heated asphalt mixture (hereinafter referred to as asphalt mixture). As shown in FIG. 1, a frame 10, which is a supporting structure, a cylindrical drum 20 rotatably mounted to the frame and having a longitudinal length of 4 to 6 times the diameter, and the cylindrical drum 20. And a drive device 30 for rotating the fuel at a predetermined speed, a burner 40 installed to be in contact with one side of the drum to dry and heat the aggregate by spraying the flame into the drum, and formed on the gas discharge side of the drum to be collected. The duct 50 for connecting with the system and the heat of the burner in the process in which the aggregate introduced to the burner installation side of the drum is transferred to the other side by the inclined drum and the drum inner blade 60. Contacting the heat-drying and comprises a drum end onto the lower committed in RAP and discharge chute (70) AC is mixed with the heated aggregate Shin installed such that the discharge side of the discharge drum.

The drum mixer is connected to the cold-bin (90) for inputting the new aggregate by adjusting the particle size in the inlet, the RAP charging conveyor 100 is connected to the RAP inlet 22 formed in the middle of the drum longitudinal section The dust collecting system 110 is connected to a duct formed at an upper end of the drum longitudinal section, and the silo 120 or the hopper 130 is connected to the discharge chute formed at the lower end of the drum longitudinal section, and the asphalt is located at the bottom of the drum longitudinal section. Cement supply pipe (AC supply pipe; 140) is connected to constitute the entire plant.

The drum mixer is inclined and the blade of the drum when the new aggregate automatically weighed in accordance with the particle size by the mixing design from the cold bean 90 in the state where the drum preheating is completed through the front end aggregate inlet 21 on the drum end ( The flames of the burner 40 are heated by contact with the bale formed by the repetition of the rising and falling by the pitch applied to the rear end, and the heated aggregate evaporates and discharges the internal moisture to be injected into the lower end of the drum. And mixed with AC or other modifiers and heated together to be discharged through a drum discharge chute above the drum end. The generated exhaust gas is absorbed into the dust collecting system 110 through the duct 50 and is discharged in a clean state in which dust and harmful elements are filtered out.

According to the structure and operation as described above, the parallel flow type drum mixer for producing an asphalt mixture has the following problems in terms of commonality and burner efficiency of asphalt pavement.

① The drum of drum mixer is designed to have end length of 4 ~ 6 times the diameter due to the limitation of installation space or movement, and the RAP inlet 22 is slightly below the center of the end of the drum to prevent deterioration of the input RAP. By forming the new aggregate may be in contact with the flame heat of the burner for a short time and then mixed with the RAP, the heat drying of the new aggregate may be incomplete.

The new aggregate should be heated and dried to have a water content of 0.5% or less, preferably 0.2% or less, before it is coated with AC. The new aggregate is coated with RAP and AC before being dried in sufficient contact with the heat of the burner. It becomes a poor dry state of more than%, which leads to peeling of the AC coating layer and increasing the water content of the heated asphalt mixture, resulting in plastic deformation and impedes long-term compatibility.

② If the fresh aggregate moisture content is high, there is a limit to the operation method of the drum mixer plant.

New aggregates for the production of regenerated heated asphalt mixtures differ in water content according to the mixing design and management conditions, and the difference in water content greatly affects drying time and efficiency.

 The optimum discharge temperature of asphalt mixture in drum mixer is about 140 ℃ ~ 150 ℃, and the higher the burner temperature, the lower the water content, the lower the RAP mixing amount, and conversely, the lower the burner temperature, the water content The higher, the lower the mixing amount of the RAP.

In general, the flame temperature of the burner is about 1400 ° C or higher, and outputting at 1400 ° C or higher causes problems such as deformation of the rigid body structure of the drum, premature aging of RAP due to heat, and flammability of AC, and inefficient consumption of fuel. . Since the input aggregate in the drum does not increase in temperature until the internal moisture is completely evaporated and dried at a temperature of about 150 ° C., when the moisture content of the input aggregate is high, the discharge temperature of the asphalt mixture through the burner temperature is limited.

In addition, the mixing amount of the RAP is determined by the blending design, and lowering the mixing amount of the RAP is not the best solution because it is not compatible with the intention of circulating resources.

One solution is to reduce the rotational speed of the drum when the water content of the input aggregate is high, and to increase the time the aggregate stays in the drum.However, if the drum rotation speed is extremely reduced, the distribution of aggregate on the drum cross section is increased. The worse the drying efficiency can be. As a result, the residence time can be adjusted to within 4 to 8 minutes by adjusting the drum speed, but there is a limit. In the same condition, the high temperature thermal contact time of the RAP and AC increases, causing excessive hardening at the contact surface with the aggregate. There is also a risk that AC performance will be reduced, such as losing.

③ RAP and AC are exposed to high temperature burner heat, so premature aging is promoted.

The premature aging of the RAP is accelerated by promoting hardening by contacting the heat of approximately 200 ℃. If the new aggregate does not absorb enough heat, there is a possibility that the heat of 200 ℃ or more is maintained at the RAP input point. Grows The optimum holding temperature for AC is 150 ° C to 180 ° C and the ignition point is approximately 330 ° C.

In general, the parallel flow type drum mixer is supplied with RAP from the burner to 1/2 to 2/3 of the length of the drum, and then AC is supplied to the new aggregate to which the convection heat of the burner is injected, so that the temperature is not lowered. Otherwise, hot flames and heat are very likely to come into contact with RAP and AC directly, resulting in blue smoke, impairing binder performance and accelerating premature aging by accelerating AC hardening, impairing the long-term utility of the packaging.

④ The non-uniformity of quality can be increased at the beginning of the operation of the drum mixer, and the fuel consumption increases as the preliminary operation time to achieve uniform quality is long.

Even when the dryer is preheated due to burner ignition, the temperature inside the dryer is drastically lowered due to the initial fresh aggregate input, and the temperature decrease affects the temperature imbalance in the drum mixer, which requires preliminary operation to stabilize the quality. As a result, the fuel consumption is increased by the reserve run time. This preliminary operating time increases the inefficiency of the operating fuel because the plant must be repeated for 3 to 4 hours when the plant is operated to produce a small amount of asphalt mixture for interval repair purposes.

Asphalt mixtures produced during the preliminary uptime are mixed with RAP and AC with new aggregates that are not sufficiently dry and contain moisture, and they are not used for packaging because they cannot meet the proper discharge temperature of the heated asphalt mixture. If the system is configured to continuously discharge the heated asphalt mixture into the silo or the temporary storage hopper, there is a problem in that facility cost is additionally required because a separate system for discharging the initial incomplete product is separately installed and discharged.

  ⑤ After the end of the asphalt mixture production, there is a problem that the energy consumption is increased by the long drum cooling operation.

In general, the parallel flow type drum mixer is discharged into the duct of the dust collecting system through the drum inclined downwardly by the hot air. In the state where the new aggregate is continuously added, the temperature in the drum is kept constant due to the cooling effect of the new aggregate, but when the new aggregate is finished, the temperature in the drum increases rapidly even after the burner is turned off, and the sudden rise in temperature keeps the drum. It is more likely to cause deformation of the frame.

Deformation of the frame due to rapid temperature rise occurs even when the burner is preheated by ignition of the burner. At this time, the temperature rises rapidly in the upper part of the burner, and the temperature unbalance occurs at a slower temperature rise.

Conventionally, in order to prevent the deformation of the drum, a method of cooling the drum by continuously operating the fan of the dust collecting system while idling the drum for 20 to 30 minutes has been used. In addition, there is a problem that the energy consumption is high due to long idle time for cooling.

An object of the present invention is to propose a parallel flow type drum mixer capable of producing asphalt mixture of uniform quality while reducing fuel consumption of a burner by controlling the operation of a drum mixer by tilt control.

In addition, the present invention improves the uniformity of the initial operating quality of the drum mixer to reduce the preliminary operating time to reduce the fuel consumption of the burner, and to suppress or prevent the degradation of the asphalt mixture produced during the preliminary operation treatment facilities for this And a parallel flow drum mixer capable of reducing costs.

 In addition, the present invention has an object of presenting a parallel flow-type drum mixer that can quickly cool the drum after the production of asphalt mixture to solve the drum deformation factor due to high temperature, and reduce the energy consumption of the drum idle for cooling.

 In addition, the present invention is to improve the distribution of the new aggregate in the drum before the RAP in the production process of regenerated heated asphalt mixture, so that the input new aggregate sufficiently absorbs the heat of the burner to constitute a parallel flow type drum mixer, By preventing heat from directly acting on the RAP and AC, it is intended to prevent premature aging of asphalt concrete and to improve the quality of asphalt concrete by maintaining an appropriate discharge temperature.

The present invention presented for this purpose is a support frame which is a support structure, a cylindrical drum rotatably mounted to the support frame, a driving device for rotating the cylindrical drum at a predetermined speed, and parallel to the flow direction of the aggregate into the drum A burner installed to dry and heat the aggregate by spraying flame, a duct formed on the gas discharge side of the drum to connect the exhaust gas to the dust collection system, an exhaust chute installed under the drum rear end, and a RAP (Reclaimed) installed above the drum rear end Asphalt Pavement (RAP) is composed of the inlet, the new aggregate injected to the burner installation side of the drum is heated and dried in contact with the heat of the burner in the process of being transferred to the other side by the inclination of the drum and the inner blade of the drum and the RAP injected from the rear end of the drum. (Reclaimed Asphalt Pavement, RAP) and AC (Asphalt Cement, AC) are mixed with heated new aggregate In the parallel flow-type drum mixer which produces a regenerated heating asphalt mixture, a support frame for rotating the drum mixer is separated from the main frame located below, and the support frame and the main frame are coupled to the discharge chute side of the drum mixer. It is characterized by the inclination adjusting device consisting of a cylinder and a hydraulic unit coupled to the hinge shaft and the new aggregate inlet side to adjust the inclination of the drum mixer in the range of -6 ° ~ + 6 ° relative to the main frame.

In addition, the present invention is to control the inclination of the drum mixer by the inclination control device by comparing the exhaust gas temperature (A) measured in the discharge duct at a predetermined time interval and the asphalt mixture discharge temperature (B) measured in the discharge chute

If A-B ≤ 10 ℃, fix at the current set angle,

If A-B> 10 ° C, the inclination control device is configured to reduce the downward inclination angle by 1 ° from the current set angle so that the inclination angle of the drum mixer is automatically adjusted according to the temperature difference between the asphalt mixture discharge temperature and the exhaust gas temperature. It features.

In addition, the present invention is to form a RAP (Reclaimed Asphalt Pavement, RAP) inlet at a position 2/3 or more of the drum length L in the burner, 1L / 18 ~ 1L / 9 of the inside of the front drum at the position where the RAP inlet is formed It is characterized by a configuration in which a backflow veil section is formed.

According to the present invention by the above configuration, the support frame and the main frame are coupled by the inclination adjusting device so that the inclination angle of the drum mixer can be changed according to the situation.

Accordingly, the method of adjusting the temperature of the burner, lowering the amount of mixing of the RAP, and reducing the number of revolutions of the drum in order to obtain proper drying and heating of the new aggregate and to obtain the proper discharge temperature of the asphalt mixture, the time the aggregate stays in the drum. In addition, the operation method of varying the inclination angle of the drum mixer according to a given situation in conjunction with drying and heating and the discharge temperature of the asphalt mixture can be applied, and the operation method by adjusting the inclination angle of the drum mixer is as follows. It offers advantages over the same existing operating methods.

① By reducing the preheating time of the drum mixer, it is possible to reduce the fuel consumption of the burner and to prevent thermal deformation of the drum and the dust collecting system.

The conventional parallel flow drum mixer is fixed to have a downward slope of -4 ° to -5 ° with respect to the horizontal plane. When the burner is ignited in the idle state of the drum mixer, heat is concentrated on the top of the burner, which is the top of the drum, In the case of not enough heat is applied, the temperature variation in the drum mixer is large, and a high temperature heat deformation occurs at the apex. In order to solve this problem, if the fan of the dust collecting system is operated normally, flame and high temperature heat flow into the dust collecting system, which causes damage to the dust collecting system. For this reason, it is common to use a method of preheating the burner for a long time with the output of the burner below the middle, thereby increasing energy consumption.

The present invention is a structure that can freely adjust the inclination of the drum mixer when preheating the drum mixer to raise the rear end of the drum mixer to 0 ° or more, and stops the operation of the exhaust fan, the drum does not collect heat to a specific part It works uniformly over the entire section of the mixer, preheating to the maximum set temperature in a short time, saving burner fuel consumption for preheating, and preventing thermal damage of the drum mixer and dust collection system due to high temperature during the preheating process. do.

② As the preliminary operation is not necessary to stabilize the quality of asphalt mixture at the initial stage of operation, it is possible to reduce the fuel cost by eliminating the preliminary operation and to save the facilities and costs for the separate discharge of the asphalt mixture produced during the preliminary operation.

When the maximum preheat temperature of the drum mixer is set to around 1000 ℃ as usual, preheat → drum mixer down slope control → burner output increase → new aggregate injection → dust collection system operation → RAP injection → AC injection → asphalt mixture discharge When the continuous operation control method is applied, the inside of the drum mixer is deprived of heat while the new input aggregate (approximately 20 ° C.) absorbs heat inside the drum mixer and rises to 100 ° C. or more. The temperature is maintained and the temperature gradually decreases according to the termination distance, so that the temperature of the gas discharged to the exhaust duct maintains the temperature drop curve of a typical parallel flow drum mixer which maintains approximately 150 ° C.

Such a typical temperature drop curve is an index for guaranteeing the quality of the regenerated heated asphalt mixture, which requires no preliminary operation by the preheating process by adjusting the tilt of the drum mixer, thereby reducing fuel costs due to eliminating the preliminary operation. The facility and cost for the separate discharge of asphalt mixtures produced in the preliminary operation can be saved.

③ The down-tilt angle of the drum mixer can be adjusted quickly according to the mixing amount of RAP and the moisture content of new aggregate that affect the quality of asphalt mixture.

The discharge temperature of asphalt mixture in the drum mixer and the moisture content of the new aggregate contained therein have a significant influence on the quality of the heating asphalt pavement.The higher the moisture content of the new aggregate, the more the RAP mixture, the harder the dry heating of the new aggregate. And the discharge temperature of the asphalt mixture is lowered.

Conventionally, in this case, a method of increasing the residence time in the drum mixer by reducing the mixing amount of the RAP or reducing the rotational speed of the drum is contrary to the purpose of using the resources and reducing the rotational speed of the drum is caused by the veil. Aggregate distribution may worsen, leading to opposite results. In the present invention, when the mixing amount of the RAP is high or the moisture content of the new aggregate is high, the aggregate aggregate in the drum mixer is maintained or increased as it is, and the aggregate aggregate in the drum mixer is decreased and the dwell time of the aggregate is increased by increasing the residence time of the aggregate. Water content and discharge can maintain the proper discharge temperature of asphalt mixture.

④ The remaining amount of aggregate and asphalt mixture in the drum mixer can be reduced.

The residual amount in the drum mixer is the amount of aggregate remaining in the drum mixer after the operation of the drum mixer, and the residue is carbonized by heating when restarted, thereby changing the physical properties of the asphalt mixture and affecting the long-term performance of the drum dryer. This increases the maintenance effort.

The residual amount is influenced by the downward tilt angle of the drum mixer, and if the residual amount is 5% or more relative to the total amount of aggregate remaining in the drum mixer at any moment during the operation of the drum mixer, the downward tilt angle of the drum mixer is not appropriate.

The present invention can minimize the residual amount in the drum mixer by giving a downward inclination angle by controlling the inclination adjusting device at the end of the operation of the drum mixer, and thus the maintenance of the drum mixer is easy to be maintained and the quality deterioration by the residue can be prevented. have.

⑤ After the end of the asphalt mixture production, the drum mixer can be cooled quickly to reduce the energy of drum mixer cooling operation.

When the discharge of the input aggregate is completed, the end of the drum mixer is lifted upward, and the heat is discharged smoothly and quickly. Therefore, deformation due to rapid temperature rise at the top of the burner immediately after the discharge of the asphalt mixture is prevented, and the cooling operation time of the drum mixer is shortened, thereby reducing energy consumption for cooling.

The reverse flow veil section according to the present invention promotes drying and heating by increasing the bale density prior to RAP injection to increase contact between new aggregates and heat flow, and absorbs high-temperature heat from new aggregates and flames with increased density. By preventing the high temperature heat acts directly on the RAP and AC to prevent the premature aging of asphalt concrete, it is possible to improve the quality of the asphalt concrete by maintaining the appropriate discharge temperature.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

2 to 5 illustrate a parallel flow type drum mixer for producing regenerated heated asphalt to which the present invention is applied, and a frame having a supporting structure and a longitudinal length of 4 to 6 times the diameter of the frame rotatably mounted on the frame. The cylindrical drum 20 to be provided, the drive device 30 for rotating the cylindrical drum 20 at a predetermined speed, and installed in contact with one side of the drum for spraying the flame into the drum to dry and heat the aggregate The burner 40, the duct 50 formed on the gas discharge side of the drum and connected to the dust collecting system 110, and the aggregate introduced to the burner installation side of the drum are inclined by the drum inclined and the drum inner blade 60. The discharge chute 70 installed on the discharge side of the drum is heated and dried in contact with the heat of the burner and the RAP and AC injected from the lower end of the drum end are mixed with the heated new aggregate and discharged. Eojinda.

In addition, the drum mixer is connected to a cold-bin (Cold-Feed Bins) 90 for the introduction of new aggregates in the aggregate inlet 21 to adjust the particle size, RAP charging conveyor in the RAP inlet 22 formed in the middle of the drum longitudinal section 100 is connected, the dust collecting system 110 is connected to the duct formed in the upper end of the drum longitudinal section, the silo 120 or the hopper 130 is connected to the discharge chute formed in the lower end of the drum longitudinal section, Asphalt cement supply pipe (AC supply pipe; 140) is connected so that the outlet is located to constitute the entire plant.

The present invention is applied to the parallel flow-type drum mixer, the frame is divided into a support frame (10A) and a main frame (10B) located below the drum mixer for rotation support, the support frame (10A) and the main frame 10B is an inclination adjusting device consisting of a hinge shaft 81 coupled to the discharge chute side of the drum mixer and a hydraulic unit 83 controlled by the cylinder 82 and the integrated controller 150 coupled to the new aggregate inlet side. By 80, the inclination of the drum mixer relative to the main frame (10B) is characterized in that it is adjusted in the range -6 ° ~ + 6 °.

The main frame 10B is formed of a rectangular box structure to stably support the upper structure as an element fixed to the foundation.

The support frame 10A has a plate structure coupled to the main frame, and a handrail 11 for safety is installed around the plate.

The drum 20 is a cylindrical body having a heat insulation layer 23 formed on the outside thereof, and ring rails 24 protrude from both sides thereof, and are coupled to the driving device 30.

The driving device 30 may be configured by forming a chain gear in the drum and connecting the driving shaft of the motor. By coupling the driving roller 32 to the geared motor 31 shaft as shown in FIG. It can be configured as a structure in which the driving force is transmitted at four points of the drum.

The drive rollers 32 are engaged in a concave-convex structure at both lower portions of the rails 24 formed on the outer side of the drum in the cross section, and each drive roller is connected to each geared motor. The driving force by the geared motor is distributed to the drum to achieve stable transmission of the driving force, and the uneven fitting of the driving roller and the rail suppresses the longitudinal displacement according to the inclination of the drum.

The burner 40 is for drying and heating the aggregate and outputs heat of 1400 ° C. or more, and a modulating burner in which temperature is controlled electronically by the integrated controller 150 is applied.

The exhaust duct 50 serves to discharge the exhaust gas inside the drum to the dust collecting system 110, and a corrugated pipe is applied to accommodate the change of the inclination.

The wing 60 is formed inside the drum to transfer aggregate injected into the drum according to the rotation of the drum, and to form an aggregate film. A lead angle is applied, and a screw wing 61 for aggregate transfer and aggregate film formation It consists of a pug mill blade 63 for mixing a veil 62 with aggregate, RAP and AC.

The screw blades 61 are formed at regular intervals along the inner wall of the drum, and a lead angle is applied to each of the screw blades so that the aggregate is transported in the drum by pushing the internal aggregate in the longitudinal direction during the rotation of the drum. .

6A and 8, the bales 62 are formed at regular intervals on the drum transversely, and the ends are bent to spread aggregate from the inner wall of the drum and reach a predetermined height when the bent ends face downward. The action of flowing down the received aggregate is continuous. With the above structure, as shown in FIG. 6B, an aggregate film is formed in the internal space of the drum, and the aggregate is dispersed in the internal space of the drum to enhance the contact between the flame and heat flow of the burner and the aggregate, thereby drying the input aggregate. Improve the heating efficiency.

As shown in FIG. 7, the pug mill blade 63 has a structure in which a square plate is protruded from the inner wall of the drum to mix and mix new aggregate, RAP and AC or other modifiers stacked on the drum bottom. .

The screw blade 61 is formed over the entire length of the drum, the screw blade formed in the first half of the drum end guides the introduced new aggregate to the bale, and the screw blade formed at the drum end portion pushes the asphalt mixture into the discharge chute. I work.

Veils formed before the end of flame expansion cool the flame with cold aggregate. To prevent this, the bales are formed at regular intervals from the point where the expansion of the flame ends.

The pug mill wing 63 is formed at the rear of the RAP inlet to mix RAP, AC, and heat-dried new aggregate.

The discharge chute 70 is for discharging the heated asphalt mixture to a silo or hopper or directly to the vehicle, and is formed at the end of the drum, and is provided with a shutter 71 so that a certain amount of asphalt mixture can be stored for a predetermined time. .

The RAP inlet 22 is formed at a point of 2/3 or more of the drum mixer length L, and as shown in FIG. 4, a continuous inlet 222 is formed in the drum transverse direction to form a RAP inlet in a single cylindrical drum. It is configured to suck the RAP filled in the hopper 221 into the drum mixer.

In the present invention, the hinge shaft 81 constituting the inclination adjusting device 80 may be configured to pass through the brackets formed on both sides of the support frame 10A and the main frame 10B, and the support frame 10A and the main frame. It is possible to form a bracket that is fitted to each other at regular intervals over the entire length of (10B), and to implement a single shaft through the configuration coupled to each bracket to achieve a more stable support structure.

The cylinder 82 stably supports the superstructure including the support frame 10A and the drum 20, and applies a hydraulic cylinder connected to the hydraulic unit 83 so as to be electronically controlled by the integrated controller when the tilting motion is imparted. do.

The present invention is configured such that the inclination of the drum mixer relative to the main frame 10B by the inclination adjusting device 80 can be adjusted in the range of -6 ° to + 6 °.

When the slope of the drum mixer is inclined downward by raising the aggregate inlet above the discharge chute based on the horizontal state of the drum mixer, -angle is given, and conversely, when the aggregate inlet is lowered below the discharge chute by inclining upward. It is configured to be adjustable in the range of -6 ° to + 6 ° when + angle is given to.

The downward slope of -6 ° of the drum mixer is the maximum inclination angle applicable to the asphalt mixture production process, and if the angle is higher, the aggregate residence time in the drum mixer is shortened to about 4 minutes, so that sufficient thermal contact is required for drying and heating the aggregate. Can not expect

Therefore, when the asphalt mixture production process is in progress, the allowable slope of the drum mixer is at least 0 ° to maximum-6 °, and the higher the moisture content of the new aggregate, the higher the RAP mixture, the closer the 0 ° is to adjust the inclination angle of the drum mixer. Increasing the dwell time without reducing the rotational speed, and vice versa-the operating method is applied to reduce the dwell time of aggregate by adjusting the angle of inclination close to -6 °.

The inclination angle adjustment of the drum mixer may be configured to be automatically performed by the integrated controller by measuring the temperature that is an index for predicting the efficiency of the drum mixer and the quality of the asphalt mixture.

The present invention compares the exhaust gas temperature (A) measured in the gas discharge duct 50 and the asphalt mixture discharge temperature (B) measured in the asphalt mixture discharge chute 70 at regular intervals as a structure of the automatic tilt control device. So

If A-B ≤ 10 ℃, fix at the current set angle,

If A-B> 10 ° C, the inclination control device is configured to reduce the downward inclination angle by 1 ° from the current setting angle so that the inclination angle of the drum mixer is automatically adjusted according to the temperature difference between the asphalt mixture discharge temperature and the exhaust gas temperature. .

The exhaust gas temperature A and the asphalt mixture discharge temperature B are indexes for predicting the efficiency of the drum mixer and the asphalt mixture quality.

If the difference between the exhaust gas temperature (A) and the asphalt mixture discharge temperature (B) is 0, the input aggregate absorbs the heat of the burner completely. For this purpose, the density of the bale and the aggregate distribution inside the drum must be perfect. However, it is only possible when the residence time of the aggregate is optimized, but in reality it is difficult to meet all of these conditions.

Therefore, a temperature difference of approximately 20 to 30 ° C. occurs in a conventional drum mixer having good performance.

The present invention measures the exhaust gas temperature (A) and the asphalt mixture discharge temperature (B) by measuring the residence time of the aggregate in the drum mixer on a periodic basis, and based on this, the hydraulic circuit is operated by the integrated controller to operate the cylinder so that the exhaust gas temperature ( A) and the asphalt mixture discharge temperature (B) will be able to automatically adjust the inclination angle of the drum mixer according to the difference.

The exhaust gas temperature (A) is measured by a thermoelectric cell installed at the inlet of the dust collecting system of the exhaust duct, and the asphalt mixture discharge temperature (B) is measured by a thermoelectric cell installed in the discharge chute. The angle and verification of the drum mixer are measured on the hinge shaft. Measure by the installed angle sensor.

If A-B> 10 ° C, the reduction angle 1 ° can be subdivided into more than 1 ° or less than 1 ° as needed when decreasing by 1 ° from the current setting angle. In consideration of the weighting method, a method of setting 1 ° or more in a predetermined range may be applied.

The present invention forms a RAP (Reclaimed Asphalt Pavement, RAP) inlet at a position 2/3 or more of the drum length L from the burner, and a backflow veil of 1L / 18 to 1L / 9 in the front drum at the position where the RAP inlet is formed. It is characterized by a configuration in which a section is formed.

As shown in FIG. 8, the bale applied to the backflow bale section is configured such that some aggregates flow backward by applying a reverse lead angle to the bale.

Part of the new aggregate input in the reflux bale section proceeds through the reflux veil section as it is, and part of the new aggregate passes through the backflow veil section while staying in the backflow section. Mixing and heat transfer eventually promotes the drying and heating of the entire aggregate, but does not affect the yield of asphalt mixtures calculated in tonnes per hour.

Bale density is increased by the backflow bale section, aggregate film is formed more densely to prevent flame from escaping to the RAP inlet section, and to prevent the heat of high temperature from directly acting on the RAP and AC. And prevent premature aging, improve the drying and heating efficiency of the new aggregate, improve the performance of the drum mixer and improve the quality of the asphalt mixture.

The reverse flow veil section is to be at least 0.5m or more and less than 1m, it is formed in the range of 1L / 18 ~ 1L / 9 of the length L of the drum mixer.

When the diameter of the drum mixer is 1.8m, the length L of the drum mixer is 9m, and the RAP inlet is formed at about 6m, and a reverse flow veil section is formed with a width of 0.5m to 1.0m at a position of about 0.3m in front of the RAP inlet.

If the counter flow veil section is shorter than 0.5m, the effective veiling cannot be formed, and if it is 1m or more, the baling is formed too thick to hinder the flow of heat flow.

9A to 9C illustrate a method of operating a drum mixer according to the present invention.

FIG. 9A is a driving method applied when the drum mixer is horizontally maintained and the residence time of the aggregate is to be increased to the maximum.

The drum mixer rotates and the burner is ignited to maintain the flame for a period of time while the exhaust fan of the dust collecting system is stopped.

The flame heat of the burner propagates to all parts of the drum mixer to maintain a uniform temperature in the drum in a short time.The preheating is completed when the thermoelectric battery installed inside the drum mix of the burner reaches a preheating temperature of about 1000 ℃. Preheating takes place in the form of a gentle drop in temperature toward the end of.

Figure 9b is added to the new aggregate in the pre-heated state, increase the burner output in the state adjusted to the initial setting angle of the drum mixer according to the water content of the new aggregate added, the new aggregate is injected, and the time difference in consideration of the transfer time sequentially RAP and AC in the state shown.

The new aggregate is rolled on the inner wall of the drum mixer and guided to the bale by the screw blades to form aggregate film on the cross section of the drum.The new aggregate is transported in the longitudinal direction of the drum mixer by the lead angle applied to the screw blades and the bale and the inclination of the drum mixer. As it is in contact with flame and heat, it is dried and heated.

When the counter flow veil section 60A is reached, a portion of the conveyance is reversed by the reverse lead angle applied to the bale, and a portion is conveyed in the forward direction continuously to form a high density baling to absorb flame and high temperature heat.

New aggregates baked at a high temperature of about 150 ℃ are mixed with the input RAP so that the temperature does not increase any more, it melts the RAP while maintaining a constant temperature, and heats AC to maintain and discharge the temperature of the entire asphalt mixture to around 150 ℃.

The heat of the burner maintains a gentle descent curve after the initial descent due to contact with new aggregates, and the final temperature is measured by a thermoelectric cell installed in the exhaust duct.

The exhaust gas temperature (A) and the asphalt mixture discharge temperature (B) are measured at intervals of residence time of the aggregate in the drum mixer, and based on this, the hydraulic circuit is operated by the integrated controller to operate the cylinder. When the inclination angle of the drum mixer according to the difference of the asphalt mixture discharge temperature (B) is configured to be automatically performed, the exhaust gas temperature (A) and the asphalt mixture discharge temperature (B) are measured at regular intervals, and the hydraulic pressure is The cylinder is operated to adjust the tilt angle of the drum mixer.

Fig. 9C shows a state in which the burner is terminated after the operation is finished, and the internal temperature of the drum is rapidly reduced by giving an upward slope while the exhaust fan is in operation.

By keeping the inclination of the drum mixer upward, heat is naturally released through the exhaust duct due to the characteristics of the heat.In this process, the drum mixer is kept constant in order to prevent the drum mixer from being deformed due to heat imbalance. The temperature drops quickly, reducing the uptime after work.

1 is a structural diagram of a conventional parallel drum mixer

2 is an external configuration diagram of a drum mixer according to the present invention

Figure 3 is an internal configuration of the drum mixer according to the present invention

4 is a cross-sectional view taken along the line A-A of FIG.

5 is a cross-sectional view taken along the line B-B of FIG.

Figure 6a is a configuration diagram of the bale of the backflow bale section

6b is a baling state diagram

7 is a configuration diagram of the pug mill blade

8 is a detailed configuration diagram of the veil applied to the backflow veil section

Figure 9a is a preheating operation state diagram of the drum mixer

9b is an asphalt mixture production state diagram of the drum mixer

9c is a cooling operation state after the end of the drum mixer

* Explanation of Major Codes

10: frame 10A: support frame 10B: mainframe

20: drum mixer 21: aggregate inlet

22: RAP inlet 23: heat insulation layer

24: rail 30: drive unit

40: burner 50: duct

60: wing 60A: reflux veil section

61: screw wing 62: veil

63: pug mill wing 70: discharge chute

80: tilt adjusting device 81: hinge shaft

82: cylinder 83: hydraulic unit

90: cold bean 100: RAP charging conveyor

110: dust collecting system 120: silo

130: hopper 140: AC supply pipe

150: integrated controller

Claims (3)

A support frame having a support structure, a cylindrical drum rotatably mounted to the support frame, a driving device for rotating the cylindrical drum at a predetermined speed, and spraying flame into the drum in parallel with the flow direction of the aggregate to aggregate the aggregate. A burner installed to dry-heat, a duct formed on the gas discharge side of the drum to connect the exhaust gas to the dust collection system, a discharge chute installed below the rear end of the drum, and a RAP (Reclaimed Asphalt Pavement (RAP) inlet installed above the drum rear end. The new aggregate injected into the burner installation side of the drum is heated and dried in contact with the heat of the burner in the process of being transferred to the other side by the inclined drum and the inner blade of the drum, and the RAP (Reclaimed Asphalt Pavement, RAP) injected from the rear end of the drum. ) And AC (Asphalt Cement, AC) are mixed with the heated new aggregate and discharged to regenerate heated asphalt In a parallel flow type drum mixer for producing a mixture, a support frame for rotating the drum mixer is separated from a main frame positioned below the support frame, and the support frame and the main frame are hinge shafts coupled to the discharge chute side of the drum mixer. Production of regenerated heated asphalt mixture characterized by adjusting the tilt of the drum mixer in the range of -6 ° to + 6 ° by the inclination adjusting device consisting of a cylinder and a hydraulic unit coupled to the new aggregate inlet side. Inclined parallel flow drum mixer The method according to claim 1, The inclination adjustment of the drum mixer by the inclination control device is performed by comparing the exhaust gas temperature (A) measured in the exhaust duct with the asphalt mixture discharge temperature (B) measured in the discharge chute by the integrated controller at regular intervals. If A-B ≤ 10 ℃, fix at the current set angle, When A-B> 10 ° C, the inclined angle of the drum mixer is automatically adjusted according to the temperature difference between the asphalt mixture discharge temperature and the exhaust gas temperature by reducing the downward inclination angle by 1 ° from the current set angle. Tilt-controlled parallel flow drum mixer for production The method according to claim 1, A RAP (Reclaimed Asphalt Pavement, RAP) inlet is formed at a position 2/3 or more of the drum length L from the burner, and a backflow veil section of 1L / 18 to 1L / 9 is formed inside the front drum at the position where the RAP inlet is formed. Slope-controlled parallel flow drum mixer for producing regenerated heated asphalt mixtures

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