Production process, equipment and system for factory-mixed warm and hot recycled asphalt mixture

Abstract

A production process includes: feeding the recycled coarse aggregates and new aggregates into the hot recycled material drying drum simultaneously through the cold material bin for heating; adding the recycled fine aggregates to the mixing cylinder of the cold recycled material mixer through the existing cold addition system for recycled materials, and then being mixed and stirred with the recycling agent after dry mixing for a certain period of time, and placing the oil-rich fine aggregates in the cold recycled material batching machine and conveyed to the cold recycled material hoist through a conveyor belt.

Claims

1. A production process for factory-mixed warm and hot recycled asphalt mixture, wherein the production process is implemented by using a production equipment for factory-mixed warm and hot recycled asphalt mixture, wherein the production equipment of factory-mixed warm and hot recycled asphalt mixture, wherein the production equipment comprises a main mixer, a hot recycled material chute, a cold recycled material chute, a hot recycled material weighing hopper, a hot recycled material temporary storage hopper, a cold recycled material mixer, a cold admixture weighing hopper, a cold admixture temporary storage hopper, a cold recycled material elevator, a hot recycled material scraper conveyor, a rejuvenator platform, a first hot recycled material elevator, a flue gas treatment device, a second hot recycled material elevator, a cold admixture heater, a combustion hot air system, and a hot recycled material drying drum mounted in a region of an equipment building frame; and a cold admixture batching machine and a hot recycled material batching machine provided on a ground; the hot recycled material chute and the cold recycled material chute are respectively mounted above the main mixer, and the hot recycled material weighing hopper and the hot recycled material temporary storage hopper are sequentially mounted above the hot recycled material chute, and the cold recycled material mixer, the cold admixture weighing hopper and the cold admixture temporary storage hopper are sequentially mounted above the cold recycled material chute; materials of the cold admixture batching machine are conveyed to the cold admixture heater through a conveyor belt, and the cold admixture heater conveys the materials to the cold admixture temporary storage hopper through the cold recycled material elevator, and the rejuvenator in the rejuvenator platform is added to the cold recycled material mixer through an addition system; the hot recycled material drying drum is provided between the second hot recycled material elevator and the first hot recycled material elevator, a temperature of the hot recycled material drying drum is controlled by the combustion hot air system, and an outlet of the first hot recycled material elevator is provided at the inlet of the hot recycled material scraper conveyor, and the materials of the hot recycled material batching machine are conveyed to the second hot recycled material elevator through a conveyor belt, and the cold admixture heater comprises heating units; the process comprises: heating 30% to 50% of recycled coarse aggregates in the hot recycled material drying drum to above 120 C., and preheating 20% to 30% of recycled oil-rich fine aggregates to 80 C. and mixing and stirring the recycled coarse aggregates and the recycled oil-rich fine aggregates with new aggregates; feeding 30% to 50% of the recycled coarse aggregates into the counterflow-heated hot recycled material drying drum through the hot recycled material batching machine and a belt conveyor, and heating to above 120 C. in the hot recycled material drying drum, lifting to the hot recycled material scraper conveyor through the first hot recycled material elevator, and conveying to the hot recycled material temporary storage hopper through the hot recycled material scraper conveyor, and entering a mixing cylinder of the main mixer through the chute after weighing by the weighing system according to a mix proportion; placing 20% to 30% of the recycled oil-rich fine aggregates in the cold admixture batching machine, conveying to the cold admixture heater through a belt conveyor for preheating to 80 C., lifting to the cold admixture temporary storage hopper of the cold recycled material through the cold recycled material elevator, and conveying to the recycled material mixer and then enter the mixing cylinder of the main mixer after weighing by the cold admixture weighing hopper; heating 20% to 50% of the new aggregates to 200 C. through the hot recycled material drying drum, screening through a vibrating screen, and entering the mixing cylinder of the main mixer after weighing according to the mix proportion; and after stirring the hot recycled coarse materials, the warm recycled oil-rich fine aggregates, and the new aggregates in the mixing cylinder of the main mixer for a certain time, stirring with an asphalt binder to produce a finished product of the recycled asphalt mixture; when the addition amount of the recycled materials is 50% to 60%, a hot mixing method is adopted, and when it is greater than 60%, a warm mixing method is adopted.

2. The production process for factory-mixed warm and hot recycled asphalt mixture according to claim 1, wherein the recycled materials are recovered from an old asphalt mixture pavement materials by milling or mechanical excavation, and are finely separated through the processes of dust removal, flexible dispersing, primary screening, primary crushing, secondary crushing, asphalt film removal, and fine screening; one kind of fine aggregate is obtained through the primary screening, and 3 to 5 kinds of coarse aggregates and one kind of oil-rich fine aggregate are obtained through the fine screening.

3. A production process for factory-mixed warm and hot recycled asphalt mixture, wherein the production process is implemented by using the production equipment for factory-mixed warm and hot recycled asphalt mixture, wherein the production equipment of factory-mixed warm and hot recycled asphalt mixture, wherein the production equipment comprises a main mixer, a hot recycled material chute, a cold recycled material chute, a hot recycled material weighing hopper, a hot recycled material temporary storage hopper, a cold recycled material mixer, a cold admixture weighing hopper, a cold admixture temporary storage hopper, a cold recycled material elevator, a hot recycled material scraper conveyor, a rejuvenator platform, a first hot recycled material elevator, a flue gas treatment device, a second hot recycled material elevator, a cold admixture heater, a combustion hot air system, and a hot recycled material drying drum mounted in a region of an equipment building frame; and a cold admixture batching machine and a hot recycled material batching machine provided on a ground; the hot recycled material chute and the cold recycled material chute are respectively mounted above the main mixer, and the hot recycled material weighing hopper and the hot recycled material temporary storage hopper are sequentially mounted above the hot recycled material chute, and the cold recycled material mixer, the cold admixture weighing hopper and the cold admixture temporary storage hopper are sequentially mounted above the cold recycled material chute; materials of the cold admixture batching machine are conveyed to the cold admixture heater through a conveyor belt, and the cold admixture heater conveys the materials to the cold admixture temporary storage hopper through the cold recycled material elevator, and the rejuvenator in the rejuvenator platform is added to the cold recycled material mixer through an addition system: the hot recycled material drying drum is provided between the second hot recycled material elevator and the first hot recycled material elevator, a temperature of the hot recycled material drying drum is controlled by the combustion hot air system, and an outlet of the first hot recycled material elevator is provided at the inlet of the hot recycled material scraper conveyor, and the materials of the hot recycled material batching machine are conveyed to the second hot recycled material elevator through a conveyor belt, and the cold admixture heater comprises heating units: the process comprises: feeding 30% to 50% of the recycled coarse aggregates into the counterflow-heated hot recycled material drying drum through the hot recycled material batching machine and a belt conveyor, and heating to above 120 C. in the hot recycled material drying drum, and heating the new aggregates to 200 C. through the hot recycled material drying drum, screening through a vibrating screen, and entering the mixing cylinder of the main mixer after weighing according to a mix proportion; the recycled coarse aggregates heated to 120 C. and the new aggregates heated to 200 C. entering the mixing cylinder of the main mixer synchronously and add part of the asphalt for pre-coating; placing 20% to 30% of recycled oil-rich fine aggregates in the cold admixture batching machine, conveying to the cold admixture heater through a belt conveyor for preheating to 80 C., lifting to the cold admixture temporary storage hopper through the elevator, and entering the recycled material mixer for pre-mixing with the rejuvenator after weighing by the cold admixture weighing hopper; subsequently, after all the aggregates are weighed according to the proportion, entering the mixing cylinder of the main mixer through a chute, and being mixed with a remaining asphalt binder to complete the mixing process and produce the finished product of the recycled asphalt mixture; when the addition amount of the recycled materials is 50% to 60%, a hot mixing method is adopted, and when it is greater than 60%, a warm mixing method is adopted.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic structural diagram of the production equipment for factory-mixed warm and hot recycled asphalt mixture with a large proportion of recycled materials proposed by the present application.

(2) FIG. 2 is a schematic structural side view of the production equipment for factory-mixed warm and hot recycled asphalt mixture with a large proportion of recycled materials proposed by the present application.

(3) FIG. 3 is a schematic block diagram of the principle of the production system for factory-mixed warm and hot recycled asphalt mixture with a large proportion of recycled materials proposed by the present application.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(4) The embodiments of the present application will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, in which the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and should not be construed as limiting the present application.

The First Embodiment

(5) A production process for factory-mixed warm and hot recycled asphalt mixture with a large proportion of recycled materials includes simultaneously feeding 10% to 50% of the recycled coarse aggregates from the cold material bin and the new aggregates into the hot recycled material drying drum 20 for heating to 200 C., and adding 20% to 30% of the recycled fine aggregates to the mixing cylinder of the cold recycled material mixer 7 through the existing cold addition system for dry-mixing for a certain period of time and then being mixed and stirred with the rejuvenator.

(6) Secondly, 20% to 30% of the oil-rich fine aggregates are placed in the cold recycled material batching machine 16, conveyed to the cold recycled material elevator 10 by a belt conveyor, lifted to the cold recycled material temporary storage hopper 9, weighed by the cold recycled material weighing hopper 8, and then conveyed to the mixing cylinder of the mixer 2 through the cold recycled material chute 4.

(7) The 10% to 50% of the recycled coarse aggregates and the new aggregates simultaneously enter the hot recycled material drying drum 20 from the cold material bin and are heated to 200 C. After being screened by a vibrating screen and weighed according to the mix proportion, they enter the mixing cylinder of the mixer 2. After dry-mixing for a certain period of time, they are mixed and stirred with asphalt. The ex-factory temperature of the finished recycled asphalt mixture is between 140 C. and 180 C.

(8) The mixing process of the recycled asphalt concrete adopts the mixing method of the existing factory-mixed hot recycling equipment. The total proportion of the recycled materials is 25% to 40%, which is suitable for various types of mixtures and layers.

Technical Indicators of the Asphalt Mixture Corresponding to Example 1

(9) TABLE-US-00001 Technical Measured Test Items Unit Requirements Indicators Dimensions of the Test mm 101.6 mm 63.5 mm Specimen The number of compaction times 75 blows for Marshall test specimen (both sides) Void ratio % 3~5 4 Percentage of voids in % 12.5 13.1 mineral aggregate, not less than Stability (MS), not less than kN 8 10.02 Flow value (FL) mm 2~4.5 3.12 Percentage of voids filled % 65~75 69.6 with asphalt (VFA) Residual stability of the % 75 86.7 immersed Marshall test, not less than Residual strength ratio of the % 70 89.9 freeze-thaw splitting test, not less than Dynamic stability of rutting, Time/mm 800 1254 not less than Failure strain of the 2300 2709.7 low-temperature bending test Asphalt-aggregate ratio % 4.5 4.5 Asphalt-aggregate ratio of % 3.6 3.6 newly added asphalt Mixing proportion of % 30 reclaimed asphalt pavement (RAP) material

The Second Embodiment

(10) A production process for factory-mixed warm and hot recycled asphalt mixture with a large proportion of recycled materials includes heating 30% to 50% of the recycled coarse aggregates to above 120 C. in the hot recycled material drying drum 20, preheating 20% to 30% of the recycled fine aggregates to 80 C. and mixing and stirring them with the new aggregates. When the addition amount of the recycled materials is 50% to 60%, the hot mixing method is adopted, and when it is greater than 60%, the warm mixing method is adopted.

(11) The 30% to 50% of the recycled coarse aggregates are fed into the counterflow-heated hot recycled material drying drum 20 through the hot recycled material batching machine 19 and the belt conveyor. They are heated to above 120 C. in the hot recycled material drying drum 20, lifted to the hot recycled material scraper conveyor 11 by the first hot recycled material elevator 13, and conveyed to the hot recycled material temporary storage hopper 6 through the hot recycled material scraper conveyor 11. After being weighed by the weighing system according to the mix proportion, they enter the mixing cylinder of the mixer 2 through the chute.

(12) The 20% to 30% of the oil-rich fine aggregates are placed in the cold recycled material batching machine 16, conveyed to the cold recycled material heater 17 by the belt conveyor for preheating to 80 C., lifted to the cold recycled material temporary storage hopper 9 by the cold recycled material elevator 10, and after being weighed by the cold recycled material weighing hopper 8, they are conveyed to the mixing cylinder of the mixer 2.

(13) The 20% to 50% of the new aggregates are heated to 200 C. through the hot recycled material drying drum 20, screened by a vibrating screen, and after being weighed according to the mix proportion, they enter the mixing cylinder of the mixer 2.

(14) After stirring the hot recycled coarse materials, the warm recycled oil-rich fine aggregates, and the new aggregates in the mixing cylinder of the mixer 2 for a certain period of time, they are mixed and stirred with asphalt. The ex-factory temperature of the finished recycled asphalt mixture is between 140 C. and 180 C.

(15) On the basis of the first Embodiment, the recycled coarse aggregates are separately heated by the hot recycled material drying drum 20 and then added. The total proportion of the recycled materials reaches 5000 to 80%. The recycled fine aggregates are preheated and added through a dedicated addition system, and the performance of the asphalt mixture is further improved.

Technical Indicators of the Asphalt Mixture Corresponding to Example 2

(16) TABLE-US-00002 Technical Measured Test Items Unit Requirements Indicators Dimensions of the Test mm 101.6 mm 63.5 mm Specimen The number of compaction time 75 blows for Marshall test specimen (both sides) Void ratio % 3~5 4.4 Percentage of voids % 12.5 13.0 in mineral aggregate, not less than Stability (MS), not less than kN 8 12.36 Flow value (FL) mm 2~4.5 2.3 Percentage of voids filled % 65~75 66.1 with asphalt (VFA) Residual stability of the % 75 79.0 immersed Marshall test, not less than Residual strength ratio of the % 70 80.0 freeze-thaw splitting test, not less than Dynamic stability of rutting, time/mm 800 3903 not less than Failure strain of the 2300 2550.5 low-temperature bending test Asphalt-aggregate ratio % 4.5 4.5 Asphalt-aggregate ratio of % 3.0 3.0 newly added asphalt Mixing proportion of % 60 reclaimed asphalt pavement (RAP) material

The Third Embodiment

(17) A production process for factory-mixed warm and hot recycled asphalt mixture with a large proportion of recycled materials includes feeding 30% to 50% of the recycled coarse aggregates into the counterflow-heated hot recycled material drying drum 20 through the hot recycled material batching machine 19 and the belt conveyor, heating them to above 120 C. in the hot recycled material drying drum 20. The new aggregates are heated to 200 C. through the hot recycled material drying drum 20, screened by the vibrating screen, and after being weighed according to the mix proportion, they enter the mixing cylinder of the mixer 2.

(18) The recycled coarse aggregates heated to 120 C. and the new aggregates heated to 200 C. simultaneously enter the mixing cylinder of the mixer 2, and part of the asphalt is added for pre-coating, and the 20% to 30% of the oil-rich fine aggregates are placed in the cold recycled material batching machine 16, conveyed to the cold recycled material heater 17 by a belt conveyor for preheating to 80 C., lifted to the cold recycled material temporary storage hopper 9 by the cold recycled material elevator 10, and after being weighed by the cold recycled material weighing hopper 8, they enter the cold recycled material mixer 7 for pre-mixing with the rejuvenator. The rejuvenator is added to the cold recycled material mixer 7 through the addition system.

(19) Subsequently, all the aggregates are weighed according to the proportion, enter the mixing cylinder of the mixer 2 through the chute, and are mixed and stirred with the remaining asphalt to complete the mixing process. The ex-factory temperature of the finished recycled asphalt mixture is between 140 C. and 180 C.

(20) On the basis of the mixing process of the recycled asphalt concrete in the second Embodiment, the pre-mixing process of the recycled fine aggregates and the rejuvenator is added, and the performance of the asphalt mixture is further improved. The total proportion of the recycled materials reaches 50% to 80%.

(21) Referring to FIGS. 1-2, a production equipment for factory-mixed warm and hot recycled asphalt mixture with a large proportion of recycled materials includes a mixer 2, a hot recycled material chute 3, a cold recycled material chute 4, a hot recycled material weighing hopper 5, a hot recycled material temporary storage hopper 6, a cold recycled material mixer 7, a cold recycled material weighing hopper 8, a cold recycled material temporary storage hopper 9, a cold recycled material elevator 10, a hot recycled material scraper conveyor 11, a rejuvenator platform 12, a first hot recycled material elevator 13, a flue gas treatment device 14, a second hot recycled material elevator 15, a cold recycled material heater 17, a combustion hot air system 18, and a hot recycled material drying drum 20 mounted in the region of the equipment building frame 1; and a cold recycled material batching machine 16 and a hot recycled material batching machine 19 provided on the ground.

(22) The hot recycled material chute 3 and the cold recycled material chute 4 are respectively mounted above the mixer 2. The hot recycled material weighing hopper 5 and the hot recycled material temporary storage hopper 4 are sequentially mounted above the hot recycled material chute 3. The cold recycled material mixer 7, the cold recycled material weighing hopper 8, and the cold recycled material temporary storage hopper 9 are sequentially mounted above the cold recycled material chute 4.

(23) The materials of the cold recycled material batching machine 16 are conveyed to the cold recycled material heater 17 through a conveyor belt. The cold recycled material heater 17 conveys the materials to the cold recycled material temporary storage hopper 9 through the cold recycled material elevator 10. The rejuvenator in the rejuvenator platform 12 is added to the cold recycled material mixer 7 through the addition system.

(24) The hot recycled material drying drum 20 is provided between the second hot recycled material elevator 15 and the first hot recycled material elevator 13. The temperature of the hot recycled material drying drum 20 is controlled by the combustion hot air system 18. The outlet of the first hot recycled material elevator 13 is provided at the inlet of the hot recycled material scraper conveyor 11. The materials of the hot recycled material batching machine 19 are conveyed to the second hot recycled material elevator 15 through a conveyor belt.

Technical Indicators of the Asphalt Mixture Corresponding to Example 3

(25) TABLE-US-00003 Technical Measured Test Items Unit Requirements Indicators Dimensions of the Test Specimen mm 101.6 mm 63.5 mm The number of compaction blows for time 75 Marshall test specimen (both sides) Void ratio % 3~5 3.7 Percentage of voids in mineral % 12.5 12.6 aggregate, not less than Stability (MS), not less than kN 8 11.66 Flow value (FL) mm 2~4.5 3.6 Percentage of voids filled with asphalt % 65~75 71 (VFA) Residual stability of the immersed % 75 105 Marshall test, not less than Residual strength ratio of the % 70 98 freeze-thaw splitting test, not less than Dynamic stability of rutting, time/mm 800 4364 not less than Failure strain of the low-temperature 2300 2556 bending test Asphalt-aggregate ratio % 4.5 4.5 Asphalt-aggregate ratio of newly % 3.0 2.9 added asphalt Mixing proportion of reclaimed % 75 asphalt pavement (RAP) material

The Fourth Embodiment

(26) Referring to FIG. 3, a production system for factory-mixed warm and hot recycled asphalt mixture with a large proportion of recycled materials includes a sensor module, a logic control module, and an actuator module; the sensor module is configured to monitor in real time the temperature data of the cold recycled material heater 17 and the hot recycled material drying drum 20. the logic control module is configured to receive the temperature data and pressure data and conduct real-time analysis and processing. Specifically: the cold recycled material heater 17 includes several heating units. The heating temperature of the heating units is obtained, an average value of the heating temperatures of all the heating units to obtain a heating average value is calculated; a temperature monitoring time zone is set, and the heating average value at any collection moment within the temperature monitoring time zone is preprocessed, the preprocessing includes calculating the average value, variance, and range, and the preprocessed value is normalized to obtain a heating value JW1.

(27) The temperature at a set position inside the hot recycled material drying drum 20 is obtained, and a temperature at any collection moment within the temperature monitoring time zone is preprocessed, and the preprocessed value to obtain a drum temperature value JW2 is normalized.

(28) A weighted calculation of the heating value and the drum temperature value is performed with a formula JW=JW1w1+JW2w2 to obtain the temperature adjustment value JW; w1 and w2 respectively represent weights of the heating value and the drum temperature value, and a set preheating temperature threshold group of the materials comprises thresholds Ja, Jb, and Jc.

(29) The temperature adjustment value is compared with any threshold in the preheating temperature threshold group includes: If 0JW<Ja, generating a low-power heating signal; If JaJW<Jb, generating a conventional heating signal; If JbJW<Jc, generating a high-power heating signal; marking the low-power heating signal, the conventional heating signal, and the high-power heating signal as the heating signal group; using a formula: Q=m.Math.c.Math.T; calculating the heat energy required to heat the materials from a current temperature to a required temperature, and obtaining a mass flow rate, a specific heat capacity, and a temperature change of the materials; wherein Q represents the required heat energy, m represents the mass flow rate of the materials, c represents the specific heat capacity, and T represents the difference between the current temperature and the required temperature; adjusting the required heat load according to the actual efficiency, and the formula is expressed as: P=Q/, to obtain the required total power P; is a thermal efficiency of the heater; obtaining a rated power p of any heating unit in the cold admixture heater 17; calculating by a formula ni=P/pki according to the rated power and the total power, to obtain the determined number ni of heating units that need to be turned on; wherein k represents the weight coefficient of the corresponding heating signal in the heating signal group, and i represents the numbers of the low-power heating signal, the conventional heating signal, and the high-power heating signal, expressed as i=1, 2 or 3.

(30) The actuator module is configured to dynamically control and adjust the heating units on the cold recycled material heater 17 according to the generated heating signal and the corresponding number of heating units to achieve the required heating effect.

(31) The present application also includes a communication module, a user access module, and a data storage module.

(32) The data storage module is configured to store the temperature data and the heating signals of the cold recycled material heater 17 and the hot recycled material drying drum 20, and the corresponding number of heating units.

(33) The user access module is configured to access the information stored in the data storage module.

(34) The communication module is configured to achieve data synchronization among the sensor module, the logic control module, and the actuator module.

(35) Based on Tables 1 and 2 of the original biochemical technical indicators of the RAP aggregates provided in the first to fourth Embodiments.

(36) TABLE-US-00004 TABLE 1 Specifications of RAP Recycled Aggregates (After Extraction) Nominal particle Specification size Mass percentage (%) passing through the following sieve apertures (mm) Name (mm) 37.5 31.5 26.5 19.0 13.2 9.5 4.75 2.36 1.18 0.6 0.3 0.15 0.075 RS9 10~20 100 90~100 0~12 0~5 RS10 10~15 100 90~100 0~12 0~5 Specification Nominal Name particle Mass percentage (%) passing through the following sieve apertures (mm) RS12 5~10 100 90~100 0~15 0~5 RS14 3~5 100 90~100 0~20 0~6 RS15 0~5 100 90~100 60~90 40~75 20~55 7~40 2~20 0~10 RS16 0~3 100 80~100 50~80 25~60 8~45 0~25 0~15

(37) Table 2 Technical indicators for the original biochemical treatment of RAP aggregates

(38) TABLE-US-00005 Test Items Unit Technical Requirements Testing Methods Stone Crushing Value % 26 JTGE42 T0316 Apparent Relative Density % >2.60 JTGE42 T0304 Water Absorption Rate % 2.0 JTGE42 T0304 Soundness % 12 JTGE42 T0314 Content of Flaky and % 15 JTGE42 T0311 Elongated Particles Asphalt Content % >4.75 mm coarse aggregates JTGE42 T0304 1.5 Measured value of fine aggregates Moisture Content % coarse aggregates 2.0 JTGE42 T0306 fine aggregates 3.0 Content of False Aggregates % 4.75 mm coarse aggregates JTGE42 T0302 15 fine aggregates 20 Sand Equivalent of Fine % 65 JTG E42 T0334 Aggregates

(39) The above are only the preferred specific implementation manners of the present application. However, the protection scope of the present application is not limited thereto. Any person skilled in the art, within the technical scope disclosed by the present application, making equivalent substitutions or changes according to the technical solutions and inventive concepts of the present application shall be covered within the protection scope of the present application.