阅读说明：本技术 一种旧沥青混合料表面沥青剥离方法 (Method for stripping asphalt on surface of old asphalt mixture ) 是由 郭佳彬 潘泽源 王俊峰 于 2021-08-23 设计创作，主要内容包括：本发明涉及一种旧沥青混合料表面沥青剥离方法,包括以下步骤：旧沥青混合料经破碎、初筛分后筛选出粗料；上述粗料经撒布平整后,将该粗料输送至喷砂装置进行沥青的喷砂剥离处理。上述喷砂装置为带供砂机构的喷砂装置,喷砂装置通过其喷口对粗料高速喷出由供砂机构供应的处理砂进行沥青的喷砂剥离处理。依照输送装置附设的称重机构检测的重量调整输送装置的输送速率和/或调整上述供砂机构的供砂量。Ⅳ.将喷砂剥离处理后的物料进行上述处理砂的回收处理。Ⅴ.将上述步骤Ⅳ处理后的物料进行二次筛分,依照物料粒径筛分为成品料。本发明实现了针对不同的粒径、输送量等情况下均能自动、有效且高效地剥离旧沥青混合料的表面沥青。(The invention relates to a method for stripping asphalt on the surface of an old asphalt mixture, which comprises the following steps: crushing and primarily screening the old asphalt mixture, and screening out coarse materials; after the coarse material is spread and leveled, the coarse material is conveyed to a sand blasting device to carry out sand blasting stripping treatment on the asphalt. The sand blasting device is provided with a sand supply mechanism, and the sand blasting device sprays the processing sand supplied by the sand supply mechanism to the coarse material at a high speed through a nozzle of the sand blasting device to perform sand blasting stripping processing on the asphalt. The conveying speed of the conveying device is adjusted and/or the sand supply amount of the sand supply mechanism is adjusted according to the weight detected by a weighing mechanism attached to the conveying device. And IV, carrying out recovery treatment on the treated sand on the material subjected to sand blasting stripping treatment. And V, screening the material treated in the step IV for the second time, and screening the material into a finished product according to the particle size of the material. The invention realizes that the surface asphalt of the old asphalt mixture can be automatically, effectively and efficiently stripped under the conditions of different particle sizes, conveying amounts and the like.)

1. A method for stripping asphalt on the surface of an old asphalt mixture is characterized by comprising the following steps: the method comprises the following steps:

crushing and primarily screening the old asphalt mixture, and screening out coarse materials;

II, after spreading and leveling the coarse material, conveying the coarse material in a single-layer curtain cloth-shaped mode by a conveying device; the conveying device is provided with a weighing mechanism, and the weighing mechanism is used for detecting the weight of the coarse material passing through in unit time in real time;

conveying the coarse material to a sand blasting device by the conveying device to perform sand blasting stripping treatment on the asphalt; the sand blasting device is provided with a sand supply mechanism, and the sand blasting device sprays the processing sand supplied by the sand supply mechanism to the coarse material at a high speed through a nozzle of the sand blasting device to perform sand blasting stripping treatment on the asphalt; adjusting the conveying speed of the conveying device and/or adjusting the sand supply amount of the sand supply mechanism according to the weight detected by the weighing mechanism in the step II;

IV, recovering the treated sand from the material subjected to sand blasting stripping treatment;

and V, performing secondary screening on the material treated in the step IV, and screening the material into a finished product according to the particle size of the material.

2. The method for stripping the asphalt from the surface of the old asphalt mixture according to claim 1, wherein the method comprises the following steps: the sand supply mechanism is of a spiral conveying structure; and adjusting the sand supply amount of the sand supply mechanism in the step III to adjust the conveying speed of the spiral conveying structure.

3. The method for stripping the asphalt from the surface of the old asphalt mixture according to claim 1, wherein the method comprises the following steps: the primary screening in the step I is to screen the crushed old asphalt mixture into coarse materials and fine materials, wherein the particle size of the coarse materials is larger than 4.75mm, and the particle size of the fine materials is smaller than or equal to 4.75 mm; and D, directly carrying out secondary screening on the fine materials and the materials treated in the step IV together.

4. The method for stripping the asphalt from the surface of the old asphalt mixture according to claim 3, wherein the method comprises the following steps: the finished product material after the secondary screening comprises a first finished product material, a second finished product material and a third finished product material, wherein the grain diameter of the first finished product material is larger than 4.75mm, the grain diameter of the second finished product material is 2.36mm-4.75mm, and the grain diameter of the third finished product material is 1.18mm-2.36 mm.

5. The method for stripping the asphalt from the surface of the old asphalt mixture according to claim 4, wherein the method comprises the following steps: the first finished material is a new aggregate used for asphalt mixture equipment or is mixed into the coarse material for use; the second finished product material and the third finished product material are used by means of separate heating or cold charging.

6. The method for stripping the asphalt from the surface of the old asphalt mixture according to claim 1, wherein the method comprises the following steps: the method for stripping the asphalt on the surface of the old asphalt mixture is a method for stripping the asphalt on the surface of the old asphalt mixture in a negative pressure environment, and the negative pressure environment is a negative pressure environment with a dust removal device; the air with dust generated by spreading and leveling the coarse material and the sand blasting stripping treatment is subjected to primary dust removal treatment and secondary dust removal treatment in sequence and then subjected to tail gas emission, and the air with dust generated by secondary screening is subjected to secondary dust removal treatment and then subjected to tail gas emission.

7. The method for stripping the asphalt from the surface of the old asphalt mixture as claimed in claim 6, wherein the method comprises the following steps: the primary dedusting is used for capturing and recovering fine aggregates with the grain size of 0.075mm-1.18 mm; the secondary dust removal is used for capturing and recovering powder with the particle size less than or equal to 0.075 mm.

8. The method for stripping the asphalt from the surface of the old asphalt mixture according to claim 1, wherein the method comprises the following steps: and III, uniformly distributing the nozzles in a row and column manner, wherein the nozzles are uniformly distributed in a direction perpendicular to the conveying direction of the conveying device.

9. The method for stripping the asphalt from the surface of the old asphalt mixture according to claim 1, wherein the method comprises the following steps: the processing sand is arranged by a material which can be absorbed by a magnetic material.

Technical Field

The invention relates to the technical field of asphalt mixture regeneration, in particular to a method for stripping asphalt on the surface of an old asphalt mixture.

Background

With the vigorous development of highway construction in recent decades, the quantity of waste asphalt mixtures generated by the overhaul and overhaul of roads is increased day by day every year, and if the waste asphalt mixtures cannot be reasonably utilized, huge resource waste and environmental pollution are brought to the society. The existing hot regeneration technology and cold regeneration technology in the industry are mainly used, and waste asphalt mixture is crushed and screened, then is subjected to heating treatment or no treatment according to a certain set proportion and is directly mixed and stirred with a certain amount of new aggregate and new asphalt to generate new asphalt mixture, and the new asphalt mixture is reused on an asphalt pavement road.

The existing cold regeneration can only be used for paving a pavement subbase layer, and the regeneration utilization rate is low. The thermal regeneration can be better applied to each base layer of the pavement according to the requirement, and the formed asphalt mixture has better quality. In the existing thermal regeneration technology, the whole old asphalt mixture (asphalt is wrapped on the surface of aggregate) is dried and heated for use, and the method has the problems that in the whole heating process of the old asphalt mixture, the asphalt on the surface of the old asphalt mixture is directly contacted with a heating medium, so that the asphalt on the surface is easy to age and scorch, the internal aggregate is slowly heated, the problems of uneven heating and the like occur, and the heating control difficulty is higher; and moreover, asphalt components on the surface of the old asphalt mixture can be greatly damaged, and the old asphalt mixture is very easy to cause the asphalt to be seriously adhered in heating equipment to cause failure in the heating process. In the process, the old asphalt mixture is very easy to cause serious asphalt adhesion in the equipment in the heating process of mechanical equipment, and the old asphalt mixture is very easy to form various complex problems such as segregation and variation, so that the quality of the final asphalt mixture is poor, and the construction quality of the pavement is influenced.

In order to solve the problems, another stripping technology for the old asphalt mixture is provided in the industry, asphalt on the surface of the old asphalt mixture is stripped from the old asphalt mixture in an external impact and friction mode, stone aggregate and asphalt sand with no asphalt on the surface or low asphalt content are obtained after the old asphalt mixture is stripped, and the stone aggregate and the asphalt sand are heated respectively. The scheme can fully utilize the old asphalt mixture, and can well avoid the problems of asphalt aging, non-uniform aggregate heating, serious asphalt mixture segregation variation, high failure rate of heating equipment and the like in the utilization process. However, the original aggregate and distribution of the asphalt mixture is easily damaged by external force impact, and the problems of poor stripping effect, low stripping efficiency and the like are caused when the adaptability of the asphalt mixtures with different particle sizes and quantities is difficult to grasp.

Disclosure of Invention

The invention provides a method for stripping asphalt on the surface of an old asphalt mixture, which aims to solve the problems that the original aggregate is easy to damage, the stripping effect is poor, the stripping efficiency is low and the like in the process of stripping the asphalt on the surface of the old asphalt mixture.

The invention adopts the following technical scheme:

a method for stripping asphalt on the surface of an old asphalt mixture comprises the following steps:

and I, crushing and primarily screening the old asphalt mixture, and then screening out coarse materials.

And II, after spreading and leveling the coarse materials, conveying the coarse materials in a single-layer curtain cloth-shaped mode by a conveying device. The conveying device is provided with a weighing mechanism, and the weighing mechanism is used for detecting the weight of the coarse material passing through in unit time in real time.

And III, conveying the coarse material to a sand blasting device by the conveying device to perform sand blasting stripping treatment on the asphalt. The sand blasting device is provided with a sand supply mechanism, and the sand blasting device sprays the processing sand supplied by the sand supply mechanism to the coarse material at a high speed through a nozzle of the sand blasting device to perform sand blasting stripping processing on the asphalt. And (3) adjusting the conveying speed of the conveying device and/or adjusting the sand supply amount of the sand supply mechanism according to the weight detected by the weighing mechanism in the step (II).

And IV, carrying out recovery treatment on the treated sand on the material subjected to sand blasting stripping treatment.

And V, screening the material treated in the step IV for the second time, and screening the material into a finished product according to the particle size of the material.

Further:

the sand supply mechanism is a spiral conveying structure. And adjusting the sand supply amount of the sand supply mechanism in the step III to adjust the conveying speed of the spiral conveying structure.

The primary screening in the step I is to screen the crushed old asphalt mixture into coarse materials and fine materials, wherein the particle size of the coarse materials is larger than 4.75mm, and the particle size of the fine materials is smaller than or equal to 4.75 mm. And (4) directly carrying out secondary screening on the fine materials and the materials treated in the step IV together.

The finished product material after the secondary screening comprises a first finished product material, a second finished product material and a third finished product material, wherein the grain diameter of the first finished product material is larger than 4.75mm, the grain diameter of the second finished product material is 2.36mm-4.75mm, and the grain diameter of the third finished product material is 1.18mm-2.36 mm.

The first finished product material is a new aggregate used for asphalt mixture equipment or is mixed into the coarse material for use. The second finished material and the third finished material are used by heating or cold charging separately.

The method for stripping the asphalt on the surface of the old asphalt mixture is a method for stripping the asphalt on the surface of the old asphalt mixture in a negative pressure environment, and the negative pressure environment is a negative pressure environment with a dust removal device. The air with dust generated by spreading and leveling the coarse material and the sand blasting stripping treatment is subjected to primary dust removal treatment and secondary dust removal treatment in sequence and then subjected to tail gas emission, and the air with dust generated by secondary screening is subjected to secondary dust removal treatment and then subjected to tail gas emission.

The primary dust removal is used for catching and recovering fine aggregates with the grain size of 0.075mm-1.18 mm. The secondary dust removal is used for capturing and recovering powder with the particle size less than or equal to 0.075 mm.

And III, arranging the nozzles in a row and column manner, and uniformly arranging the nozzles along the direction vertical to the conveying direction of the conveying device.

The processing sand is made of a material which can be adsorbed by a magnetic material.

As is apparent from the above description of the present invention, the present invention has the following advantages compared to the prior art:

firstly, the invention peels off the asphalt on the surface of the coarse material through sand blasting peeling treatment, and can well control the collision force of the treated sand and the coarse material by adjusting the air pressure of high-pressure gas for driving the treated sand, thereby effectively reducing the condition of concentrated distribution and damage of the original mixture. The coarse material on the conveying device is obtained by spreading the coarse material into a single-layer curtain cloth shape matched with the weighing mechanism, so that the conveying speed of the conveying device and/or the sand supply amount of the sand supply mechanism are automatically adjusted, and the surface asphalt of the old asphalt mixture can be automatically, effectively and efficiently stripped under the conditions of different particle sizes, conveying amounts and the like.

Secondly, since fine aggregates with a particle size of less than 4.75mm are very important for the quality control of the raw materials of the asphalt mixture, the division of the three above-mentioned finished materials in the invention is helpful for controlling the gradation quality of the added recycled asphalt mixture.

Drawings

FIG. 1 is a process flow chart of the asphalt stripping method for the surface of the old asphalt mixture.

Detailed Description

The following describes embodiments of the present invention with reference to the drawings.

Referring to fig. 1, a method for stripping asphalt from the surface of an old asphalt mixture comprises the following steps:

crushing and primarily screening an old Asphalt mixture (namely RAP in figure 1), and screening the crushed old Asphalt mixture into coarse materials and fine materials, wherein the particle size of the coarse materials is larger than 4.75mm, and the particle size of the fine materials is smaller than or equal to 4.75 mm.

Wherein, because the fine aggregate with the grain diameter of less than 4.75mm is very important for the quality control of the raw materials of the asphalt mixture, 4.75mm is selected as the grain diameter for dividing coarse materials and fine materials.

And II, after spreading and leveling the coarse materials, conveying the coarse materials in a single-layer curtain cloth-shaped mode by a conveying device. The conveying device is provided with a weighing mechanism, and the weighing mechanism is used for detecting the weight of the coarse material passing through in unit time in real time. The spreading can be realized by material spreading equipment, and even matched with structures such as height limiting cross bars. The conveying device is provided with a weighing mechanism and even the matching of the conveying device and the spreading equipment, and is often applied to the field of quantitative conveying and mixing of materials, and the details are not repeated here.

And III, conveying the coarse material to a sand blasting device by the conveying device to perform sand blasting stripping treatment on the asphalt. The sand blasting device is provided with a sand supply mechanism, and the sand blasting device sprays the processing sand supplied by the sand supply mechanism to the coarse material at a high speed through a nozzle of the sand blasting device to perform sand blasting stripping processing on the asphalt. And (3) adjusting the conveying speed of the conveying device and/or adjusting the sand supply amount of the sand supply mechanism according to the weight detected by the weighing mechanism in the step (II).

The processing sand is arranged by a material which can be absorbed by a magnetic material, such as steel grit and the like. The sand blasting device is applied to carbon deposition treatment, sand blasting and rust removal and the like of the engine. Materials such as iron, cobalt and nickel which can be adsorbed by magnetic materials can be adopted to realize recycling of the treated sand through the iron removal device, so that the sand blasting device is convenient to apply. The sand blasting device can control the collision force between the processed sand and the coarse material by adjusting the air pressure of high-pressure gas for driving the processed sand aiming at different old asphalt mixtures.

The sand supply mechanism is a spiral conveying structure. The sand supply amount of the sand supply mechanism is adjusted to adjust the conveying speed of the spiral conveying structure.

The processing sand, such as spherical steel grit, is sprayed to the cord fabric-shaped material at a high speed, and the high-speed steel grit is fully and effectively impacted with the surface of the material, so that the asphalt on the surface of the material is smoothly stripped from the surface of the asphalt mixture. After the weighing mechanism is used for weighing and metering, the material quantity entering the sand blasting device is judged according to the weight of coarse particles of the asphalt mixture passing through the weighing mechanism in unit time through real-time detection. When the amount of the fed materials is increased, the spiral conveying rotating speed of the sand supply mechanism can be increased in modes such as frequency conversion control and the like, and the injection amount of steel sand is increased; in addition, the conveying speed of the conveying device can be controlled in modes such as frequency conversion control and the like according to needs, the conveying speed is reduced, the retention time of the material in the sand blasting device is prolonged, the material can be in sufficient collision friction with steel grit for a long time, and the stripping efficiency is greatly improved. When the entering materials are reduced, the spiral rotating speed can be reduced and/or the conveying speed can be increased, so that the stripping effect can be ensured, and the waste of excessive energy consumption and unnecessary loss of equipment can be avoided.

The nozzles are arranged in rows and columns and are uniformly distributed along the direction vertical to the conveying direction of the conveying device. Specifically, each row of nozzles extends and is arranged along the conveying direction, each row of nozzles extends and is arranged along the direction perpendicular to the conveying direction, and the nozzles are uniformly arranged along the row and column directions. And be located spout transport the place ahead and can set up a camera that has machine vision, should arrange the camera along the direction extension of perpendicular to direction of delivery and a camera and every row of spout one-to-one setting. When the conveying device conveys the assigned distance, the camera further quantifies the materials in the area by acquiring the proportion of the material coverage surface in the plane where the conveying belt of the conveying device is located in the visual range of the camera, and the quantity selection of the opening of the nozzles is matched with the camera, so that the asphalt stripping efficiency is further improved. The application of the machine vision is a further scheme of the old asphalt mixture surface asphalt stripping method in the specific embodiment, and the further effect of automatically, effectively and efficiently stripping the surface asphalt of the old asphalt mixture is improved.

And IV, carrying out recovery treatment on the treated sand on the material subjected to sand blasting stripping treatment. The treated sand is absorbed and recovered from the materials through an iron removal device and is sent back to the step III for recycling.

And V, carrying out secondary screening on the material treated in the step IV and the fine material screened in the step I together, and screening the material into a finished product according to the particle size of the material. The finished product material after the secondary screening comprises a first finished product material, a second finished product material and a third finished product material, wherein the grain diameter of the first finished product material is larger than 4.75mm, the grain diameter of the second finished product material is 2.36mm-4.75mm, and the grain diameter of the third finished product material is 1.18mm-2.36 mm.

Specifically, the method for stripping the asphalt on the surface of the old asphalt mixture is a method for stripping the asphalt on the surface of the old asphalt mixture in a negative pressure environment, and the negative pressure environment is a negative pressure environment with a dust removal device. The air with dust generated by spreading and leveling the coarse material and the sand blasting stripping treatment is subjected to primary dust removal treatment and secondary dust removal treatment in sequence and then subjected to tail gas emission, and the air with dust generated by secondary screening is subjected to secondary dust removal treatment and then subjected to tail gas emission. The primary dust removal is used for catching and recovering fine aggregates with the grain size of 0.075mm-1.18 mm. The secondary dust removal is used for capturing and recovering powder with the particle size less than or equal to 0.075 mm. In the secondary screening, the fine materials with the grain diameter less than or equal to 1.18mm are easily influenced by the airflow and enter the dust removal device. The first finished product material is a new aggregate used for asphalt mixture equipment or is mixed into the coarse material for use. The second finished material and the third finished material are used by heating or cold charging separately.

According to the invention, the primary dust removal and the secondary dust removal are arranged, on the premise of ensuring the recovery and utilization of dust particles to the maximum degree, the air with dust generated by secondary screening is directly subjected to secondary dust removal treatment in a targeted manner, the air with dust generated by spreading and leveling coarse materials and sand blasting stripping treatment is subjected to primary dust removal treatment firstly and then is subjected to secondary dust removal treatment together with the air with dust generated by secondary screening, and then tail gas emission is carried out.

The above description is only an embodiment of the present invention, but the design concept of the present invention is not limited thereto, and any insubstantial modifications made by using the design concept should fall within the scope of infringing the present invention.