CN109609168B - Production process of asphalt - Google Patents
Production process of asphalt Download PDFInfo
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- CN109609168B CN109609168B CN201811472445.4A CN201811472445A CN109609168B CN 109609168 B CN109609168 B CN 109609168B CN 201811472445 A CN201811472445 A CN 201811472445A CN 109609168 B CN109609168 B CN 109609168B
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10C—WORKING-UP PITCH, ASPHALT, BITUMEN, TAR; PYROLIGNEOUS ACID
- C10C3/00—Working-up pitch, asphalt, bitumen
- C10C3/14—Solidifying, Disintegrating, e.g. granulating
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- Chemical Kinetics & Catalysis (AREA)
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- General Chemical & Material Sciences (AREA)
- Structural Engineering (AREA)
- Materials Engineering (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Organic Chemistry (AREA)
- Processing Of Solid Wastes (AREA)
- Road Paving Structures (AREA)
- Working-Up Tar And Pitch (AREA)
Abstract
The invention provides a production process of asphalt, which breaks through the traditional asphalt recovery process form and carries out primary crushing on waste asphalt to prepare primary particles; primary cleaning is carried out on the primary particles, primary impurity removal is carried out, and primary impurity removal particles are prepared; cooling the primary impurity-removed particles to make the asphalt in the primary impurity-removed particles in a glass state and prepare glass state particles; grinding the glassy state particles to separate asphalt particles and impurity particles in the glassy state particles from each other to prepare ground fine particles; carrying out primary air separation on the ground and ground particles under the condition of ensuring that the asphalt in the ground and ground particles is in a glass state, and removing impurity particles with the density smaller than that of the asphalt to prepare impurity-removed fine particles; and carrying out secondary air separation on the impurity-removed fine particles under the condition of ensuring that the asphalt in the impurity-removed fine particles is in a glass state, and removing impurity particles with the density higher than that of the asphalt. Therefore, the invention can process the asphalt efficiently and quickly, has concise and clear steps, saves resources and protects the environment.
Description
Technical Field
The invention relates to the field of material processing, in particular to a production process of asphalt.
Background
The asphalt can be aged after long-term use, particularly, physical and chemical reactions such as volatilization, oxidation and polymerization can occur due to the long-term contact of the asphalt with sunlight, oxygen, moisture and the like, so that the aging phenomenon is easy to occur, and the service life of the asphalt is seriously influenced. And limited resources can not support more and more use, the existing use amount of waste asphalt, particularly pavement asphalt, is huge, and how to recover the waste asphalt becomes an asphalt production process which is more and more valued.
For example, chinese patent CN 201711027446.3 discloses a method for recycling, reinforcing and reusing waste road asphalt, which comprises the steps of grinding the recycled road asphalt containing pebbles, crushing the pebbles, uniformly mixing the crushed mixture with waste plastics and waste fabrics, performing shearing and mixing reaction in a conical screw extruder to re-disperse the agglomerated asphaltenes into a high-toughness colloid structure, cooling and granulating to obtain the special recycled asphalt material for road surfaces, wherein the preparation method comprises the following specific steps: (1) adding the recycled road asphalt containing the stones into a high-pressure suspension roller mill, after the recycled asphalt enters a milling cavity, shoveling the recycled asphalt by a shovel blade, sending the recycled asphalt between a milling roller and a magic ring to mill the stones into powder, then carrying the powder into an analyzer along with circulating air of an air blower, separating the powder by cyclone after the granularity meets the requirement, and returning larger particles to the analyzer for re-milling; (2) adding the regenerated asphalt material obtained in the step (1), waste plastics and crushed waste woven fabrics into a mixer according to a certain mass ratio, uniformly mixing, cooling and discharging; (3) adding the mixture obtained in the step (2) into a conical screw extruder, reasonably setting the heating temperature of each section, starting an air cooling system, checking and confirming that an exhaust hole is not blocked, starting a motor, feeding after running is stable, and adjusting the feeding speed and the screw rotation speed to match; after the materials enter an extruder, the materials enter a compression section firstly, then enter a homogenization section for shearing and mixing reaction, waste plastics and waste fabrics are injected into the pavement asphalt, so that the condensed asphaltene is re-dispersed into a high-toughness colloid structure, and then the regenerated asphalt material special for the pavement is obtained through cooling and granulation. The pressure of a high-pressure spring of the high-pressure suspension roller grinding machine in the step (1) is 1200kg for 1000-. The particle size of the stones ground by the high-pressure suspension roller grinding mill in the step (1) is not more than 50 meshes. The waste plastics in the step (2) are at least one of recycled polyethylene, polypropylene, polystyrene or polyvinyl chloride, and the size of each direction of the crushed materials is not more than 3 mm. The waste fabric in the step (2) comprises various recycled fabrics of natural fibers or synthetic fibers, and the all-directional size of the crushed material of the waste fabric is not more than 3 mm. The total parts by mass of the mixture in the step (2) are 100 parts, wherein 50-70 parts of regenerated asphalt, 20-30 parts of waste plastic and 10-20 parts of waste fabric. The mixer in the step (2) is a colter mixer, a ribbon mixer or a V-shaped mixer, and the mixing time is 20-30 min. And (3) adopting an electrical control system for the conical screw extruder, wherein the main driving mode is variable frequency speed regulation, and the length-diameter ratio of the screw is 20:1-30: 1. The heating temperature of each section of the extruder in the step (3) is 120 ℃ plus 140 ℃, the compression section is 140 ℃ plus 150 ℃, and the homogenization section is 150 ℃ plus 160 ℃. The feeding speed in the step (3) is 200-250g/min, and the screw rotating speed is 80-110 r/min.
Meanwhile, the impurities in the pavement asphalt are mainly sand and dust, wherein the dust is basically less than the density of water, more less than the density of asphalt (1.15-1.25g per cubic centimeter), and the density of most of sand (more than 2g per cubic centimeter) is obviously greater than that of asphalt.
Accordingly, the present inventors have made extensive studies to solve the above problems and have made the present invention.
Disclosure of Invention
The invention aims to provide the asphalt production process which can efficiently and quickly process asphalt, has simple and clear steps, saves resources and protects the environment.
In order to achieve the purpose, the invention adopts the following technical scheme:
a production process of asphalt comprises the following steps:
(1) carrying out primary crushing on waste asphalt to prepare primary particles;
(2) then primary cleaning is carried out on the primary particles, primary impurity removal is carried out, and primary impurity removal particles are prepared;
(3) then cooling the primary impurity-removed particles to make the asphalt in the primary impurity-removed particles in a glass state to prepare glass state particles;
(4) grinding the glassy state particles to separate asphalt particles and impurity particles in the glassy state particles from each other to prepare ground fine particles;
(5) then, carrying out primary air separation on the ground and ground particles under the condition of ensuring that the asphalt in the ground and ground particles is in a glass state, and removing impurity particles with the density smaller than that of the asphalt to prepare impurity-removed fine particles;
(6) secondly, carrying out secondary air separation on the impurity-removed fine particles under the condition of ensuring that the asphalt in the impurity-removed fine particles is in a glass state, and removing impurity particles with the density higher than that of the asphalt;
(7) the bitumen granules are then removed.
In the step (7), the asphalt particles after being taken out are heated, and a regenerant is added to the asphalt particles for stirring.
The regenerant is mainly an aromatic component.
In the step (1), waste asphalt is firstly collected; the waste asphalt is waste pavement asphalt.
And (3) drying and dehydrating the primary impurity-removed particles between the steps (2) and (3).
In the step (1), the primary particles are crushed to 3 to 10 mesh.
In the step (4), the ground fine particles are ground to 18 to 400 mesh.
In the step (4), the glassy particles are ground in an environment at a temperature of less than-35 ℃.
In the step (4), the glassy particles are ground by a grinder, and air or nitrogen having a temperature of less than-35 ℃ is introduced into the grinder during the grinding.
In the step (5), performing primary air separation on the ground particles by using air or nitrogen with the temperature lower than-35 ℃; in the step (6), air or nitrogen with the temperature lower than-35 ℃ is used for carrying out secondary air separation on the impurity-removed fine particles.
After the technical scheme is adopted, the production process of the asphalt breaks through the traditional asphalt recovery process form, and the waste asphalt is subjected to primary crushing to prepare primary particles; the step can expose impurities such as dust on the surface of the waste asphalt and in cracks, and the primary crushing is carried out to facilitate the subsequent further grinding. Then primary cleaning is carried out on the primary particles, primary impurity removal is carried out, and primary impurity removal particles are prepared; the step can remove impurities such as dust and the like attached to the surface of the waste asphalt. Then cooling the primary impurity-removed particles to make the asphalt in the primary impurity-removed particles in a glass state to prepare glass state particles; the step can lead the waste asphalt to be in a hard and brittle glass state, and is convenient for grinding the waste asphalt into fine particles. Grinding the glassy state particles to separate asphalt particles and impurity particles from each other to prepare ground fine particles (such as sand grain size in desert or beach); the step can grind the impurities such as asphalt, gravel and the like in the glass state particle grinding into fine asphalt particles and impurity particles, the asphalt particles and the impurity particles are obviously granular, particularly the impurity particles are in round granules, the contact surface of the asphalt particles and the impurity particles is reduced, the adhesion force of the asphalt particles and the impurity particles is lost, and the asphalt particles and the impurity particles are separated from each other and are loosened. Then, carrying out primary air separation on the ground and ground particles under the condition of ensuring that the asphalt in the ground and ground particles is in a glass state, and removing impurity particles with the density smaller than that of the asphalt to prepare impurity-removed fine particles; in the step, impurities with the density smaller than that of the asphalt, such as dust and the like, which are further exposed after grinding are removed through air separation, and meanwhile, the asphalt in the ground fine particles is ensured to be in a glass state and lose the bonding property, so that the asphalt is prevented from being bonded with the impurities again. Secondly, carrying out secondary air separation on the impurity-removed fine particles under the condition of ensuring that the asphalt in the impurity-removed fine particles is in a glass state, and removing impurity particles with the density higher than that of the asphalt; the impurities with the density higher than that of the asphalt, which are exposed after grinding, are removed through air separation, and meanwhile, the asphalt in the ground fine particles is ensured to be in a glass state and lose the bonding property, so that the asphalt is prevented from being bonded with the impurities again. The bitumen granules are then removed for use. Compared with the prior art, the production process of the asphalt can efficiently and quickly process the asphalt, has simple and clear steps, saves resources and protects the environment.
Detailed Description
In order to further explain the technical solution of the present invention, the following detailed description is given by way of specific examples.
The invention relates to a production process of asphalt, which comprises the following steps:
(1) carrying out primary crushing on waste asphalt to prepare primary particles; the step can expose impurities such as dust on the surface of the waste asphalt and in cracks, and the primary crushing is carried out to facilitate the subsequent further grinding.
(2) Then primary cleaning is carried out on the primary particles, primary impurity removal is carried out, and primary impurity removal particles are prepared; the step can remove impurities such as dust and the like attached to the surface of the waste asphalt.
(3) Then cooling the primary impurity-removed particles to make the asphalt in the primary impurity-removed particles in a glass state to prepare glass state particles; the step can lead the waste asphalt to be in a hard and brittle glass state and be easy to grind and crush, and is convenient for grinding the waste asphalt into fine particles.
(4) Grinding the glassy state particles to separate asphalt particles and impurity particles from each other to prepare ground fine particles (such as sand grain size in desert or beach); the step can grind the impurities such as asphalt, gravel and the like in the glass state particle grinding into fine asphalt particles and impurity particles, the asphalt particles and the impurity particles are obviously granular, particularly the impurity particles are in round granules, the contact surface of the asphalt particles and the impurity particles is reduced, the adhesion force of the asphalt particles and the impurity particles is lost, and the asphalt particles and the impurity particles are separated from each other and are loosened.
(5) Then, carrying out primary air separation on the ground and ground particles under the condition of ensuring that the asphalt in the ground and ground particles is in a glass state, and removing impurity particles with the density smaller than that of the asphalt to prepare impurity-removed fine particles; in the step, impurities with the density smaller than that of the asphalt, such as dust and the like, which are further exposed after grinding are removed through air separation, and meanwhile, the asphalt in the ground fine particles is ensured to be in a glass state and lose the bonding property, so that the asphalt is prevented from being bonded with the impurities again.
Alternatively, the ground particles may be washed while maintaining the pitch in the ground particles in a glassy state, for example, by washing the ground particles with a low melting point solution, which may be an inorganic salt solution for adjusting the melting point and density, so that the inorganic salt solution does not solidify in a low temperature environment in which the glassy state of the pitch is maintained.
(6) Secondly, carrying out secondary air separation on the impurity-removed fine particles under the condition of ensuring that the asphalt in the impurity-removed fine particles is in a glass state, and removing impurity particles with the density higher than that of the asphalt; the impurities with the density higher than that of the asphalt, which are exposed after grinding, are removed through air separation, and meanwhile, the asphalt in the ground fine particles is ensured to be in a glass state and lose the bonding property, so that the asphalt is prevented from being bonded with the impurities again.
Or, under the condition of ensuring that the asphalt in the impurity-removed fine particles is in a glass state, the impurity-removed fine particles can be placed in the separation liquid to separate the asphalt particles from the impurity particles with the density higher than that of the asphalt, so that the impurity particles sink to the bottom of the separation liquid, the asphalt particles float on the surface of the separation liquid, and the density of the separation liquid is between the density of the asphalt and the density of the impurity particles; because the density of the asphalt (1.15-1.25g per cubic centimeter) is less than that of the sand (more than 2g per cubic centimeter), the separation liquid can be inorganic salt aqueous solution, and the density is adjusted to be 1.25-2.65g per cubic centimeter, which is between the density of the asphalt and the density of the sand, so the inorganic salt solution can not be solidified in the low-temperature environment for keeping the glass state of the asphalt.
(7) The bitumen granules are then removed for use.
Preferably, in the step (7), the asphalt particles after being taken out are heated and added with a regenerant for stirring. The regenerant is used for preparing the proportions of saturated phenol, aromatic component, colloid and asphaltene in the asphalt, so that the proportions of the components are rebalanced to be close to fresh asphalt, and the asphalt can be reused as fresh asphalt, pavement asphalt and other purposes and has more selectivity.
Preferably, the regenerant is mainly aromatic, and mainly supplements the aromatic components lost too much in the aging process of the asphalt, and also can appropriately supplement some saturated phenol so as to ensure that the proportion of the saturated phenol in the regenerated asphalt with the increased total amount is not reduced.
Preferably, in the step (1), the waste asphalt is collected firstly; the waste asphalt is waste pavement asphalt. The step can provide sufficient raw materials for asphalt production, has low cost, saves resources and protects the environment.
Preferably, between steps (2) and (3), the primary de-watered particles are dried to remove water. The step can avoid the icing condition in the process of cooling the primary impurity-removed particles to realize the asphalt glass state in the step (3), and avoid the influence of ice on the grinding of the glass state particles due to the increase of lubrication in the grinding process.
Preferably, in step (1), the primary particles are crushed to 3-10 mesh. The primary particles of this size can substantially expose impurities such as dust on the surface and in cracks of the waste asphalt. The primary particles may be specifically 3, 4, 5, 6, 7, 8, 9 and 10 mesh.
Preferably, in step (4), the ground fine particles are ground to 18 to 400 mesh. The grinding fine particles with the particle size are similar to sand particles on deserts or sandy beach and are more perfectly round, the contact surface of the asphalt particles and the impurity particles is small enough, so that the asphalt particles and the impurity particles lose adhesive force, and the asphalt particles and the impurity particles are separated from each other and are loose.
Preferably, in step (4), the glassy particles are milled in an environment having a temperature below-35 ℃. The glass state of the asphalt can be realized at about-33 ℃, in order to ensure the glass state stability of the glass state particles, the glass state particles are ground in an environment of-35 ℃, if the conditions allow, the glass state particles are preferably ground in an environment of less than-40 ℃, and considering the restrictions of cost, conditions and the like, the glass state particles are preferably between-35 ℃ and-50 ℃, and can be specifically between-35 ℃, 40 ℃, 45 ℃ and-50 ℃.
Preferably, in the step (4), the glassy state particles are ground by a grinder, and air or nitrogen with a temperature of lower than-35 ℃ is introduced into the grinder during the grinding process, so that the glassy state particles can be kept in a low-temperature glassy state all the time by introducing air or nitrogen with a temperature of lower than-35 ℃ into the grinder during the grinding process, and the grinding process is facilitated. And the nitrogen can prevent the asphalt particles from being oxidized and protect the asphalt particles. If the conditions allow, air or nitrogen with the temperature lower than-40 ℃ is preferably introduced in the grinding process, and considering the restrictions of cost, conditions and the like, the temperature is preferably between-35 ℃ and-50 ℃, and can be specifically-35, -40, -45 and-50 ℃.
Preferably, in step (5), the ground particles are subjected to a first air separation using air or nitrogen at a temperature below-35 ℃; in the step (6), air or nitrogen with the temperature lower than-35 ℃ is used for carrying out secondary air separation on the impurity-removed fine particles. Air or nitrogen with the temperature lower than-35 ℃ is adopted in the air separation process, so that the glassy state particles can be kept in a low-temperature glassy state all the time, and the particles cannot be adhered. And the nitrogen can prevent the asphalt particles from being oxidized and protect the asphalt particles. If the conditions allow, air or nitrogen with the temperature lower than-40 ℃ is preferably adopted in the air separation process, and considering the limits of cost, conditions and the like, the temperature is preferably between-35 ℃ and-50 ℃, and can be specifically-35, -40, -45 and-50 ℃.
The product form of the present invention is not limited to the embodiments and examples shown in the present application, and any suitable changes or modifications of the similar ideas should be made without departing from the patent scope of the present invention.
Claims (10)
1. The production process of the asphalt is characterized by comprising the following steps of:
(1) carrying out primary crushing on waste asphalt to prepare primary particles;
(2) then primary cleaning is carried out on the primary particles, primary impurity removal is carried out, and primary impurity removal particles are prepared;
(3) then cooling the primary impurity-removed particles to make the asphalt in the primary impurity-removed particles in a glass state to prepare glass state particles;
(4) grinding the glassy state particles to separate asphalt particles and impurity particles in the glassy state particles from each other to prepare ground fine particles;
(5) then, carrying out primary air separation on the ground and ground particles under the condition of ensuring that the asphalt in the ground and ground particles is in a glass state, and removing impurity particles with the density smaller than that of the asphalt to prepare impurity-removed fine particles;
(6) secondly, carrying out secondary air separation on the impurity-removed fine particles under the condition of ensuring that the asphalt in the impurity-removed fine particles is in a glass state, and removing impurity particles with the density higher than that of the asphalt;
(7) the bitumen granules are then removed.
2. A process for the production of bitumen as claimed in claim 1, wherein: in the step (7), the asphalt particles after being taken out are heated, and a regenerant is added to the asphalt particles for stirring.
3. A process for the production of bitumen as claimed in claim 2, wherein: the regenerant is mainly an aromatic component.
4. A process for the production of bitumen as claimed in claim 3, wherein: in the step (1), waste asphalt is firstly collected; the waste asphalt is waste pavement asphalt.
5. A process for the production of bitumen as claimed in claim 4, wherein: and (3) drying and dehydrating the primary impurity-removed particles between the steps (2) and (3).
6. A process for the production of bitumen as claimed in claim 5, wherein: in the step (1), the primary particles are crushed to 3 to 10 mesh.
7. A process for the production of bitumen as claimed in claim 6, wherein: in the step (4), the ground fine particles are ground to 18 to 400 mesh.
8. A process for the production of bitumen as claimed in claim 7, wherein: in the step (4), the glassy particles are ground in an environment at a temperature of less than-35 ℃.
9. A process for the production of bitumen as claimed in claim 7, wherein: in the step (4), the glassy particles are ground by a grinder, and air or nitrogen having a temperature of less than-35 ℃ is introduced into the grinder during the grinding.
10. A process for the production of bitumen as claimed in claim 1, wherein: in the step (5), performing primary air separation on the ground particles by using air or nitrogen with the temperature lower than-35 ℃; in the step (6), air or nitrogen with the temperature lower than-35 ℃ is used for carrying out secondary air separation on the impurity-removed fine particles.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811472445.4A CN109609168B (en) | 2018-12-04 | 2018-12-04 | Production process of asphalt |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811472445.4A CN109609168B (en) | 2018-12-04 | 2018-12-04 | Production process of asphalt |
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| Publication Number | Publication Date |
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| CN109609168A CN109609168A (en) | 2019-04-12 |
| CN109609168B true CN109609168B (en) | 2020-09-25 |
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| CN201811472445.4A Expired - Fee Related CN109609168B (en) | 2018-12-04 | 2018-12-04 | Production process of asphalt |
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Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN116020656B (en) * | 2022-12-30 | 2024-02-02 | 辽宁润兴新材料有限公司 | Impurity removing device for processing coated asphalt material |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN204448790U (en) * | 2014-12-31 | 2015-07-08 | 青海第六路桥建设有限公司 | A kind of novel building waste asphalt material recuperating machines |
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Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN204448790U (en) * | 2014-12-31 | 2015-07-08 | 青海第六路桥建设有限公司 | A kind of novel building waste asphalt material recuperating machines |
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