CN1857782A

CN1857782A - Waste concrete component separating method

Info

Publication number: CN1857782A
Application number: CN 200610019242
Authority: CN
Inventors: 何永佳; 胡曙光; 吕林女; 丁庆军
Original assignee: Wuhan University of Technology WUT
Current assignee: Wuhan University of Science and Engineering WUSE; Wuhan University of Technology WUT
Priority date: 2006-06-01
Filing date: 2006-06-01
Publication date: 2006-11-08
Anticipated expiration: 2026-06-01
Also published as: CN100398214C

Abstract

The present invention belongs to the field of building material, and is especially waste concrete component separating method. The waste concrete component separating method includes the following steps: heating, pulverizing or other steps to expand and increase micro cracks inside concrete, extruding or adding friction force and sieving to separate coarse aggregate and mortar; and pulverizing mortar to separate quartzite and cement of different milling property and density in mill with pneumatic action. The said method can separate coarse aggregate, fine aggregate and cement in waste concrete in high efficiency and high quality.

Description

The method that a kind of waste concrete component separates

Technical field

The invention belongs to building material field, be specifically related to a kind of method that coarse aggregate, fine aggregate and cement stone component in the discarded concrete are separated from each other.

Background technology

In waste and old concrete structural demolition process, and in the concrete production process, produce a large amount of discarded concretes.Expansion and a large amount of old concrete structure with the capital construction scale arrives Years Of Service at present, and the generation of discarded concrete increases with surprising rapidity.Processing method for discarded concrete generally is to be used as building waste to throw aside, but such processing method exists tangible drawback, the one, and the landfill of discarded concrete is stacked the land resource that takies a large amount of preciousnesses; The 2nd, easily environment is caused secondary pollution; Simultaneously, discarded concrete exists the value of regeneration, it is thrown aside in fact caused waste to resource.Under the deficient day by day severe situation of the concrete raw material of preparation, each component separation is recycled and is significant to discarded concrete.

For the still unhardened discarded concrete that produces in the concrete production process, existing at present correlation technique and equipment clean it, sand, stone more fully can be separated and be recycled.The recycling of people to the sclerosis discarded concrete that produces in waste and old concrete structural demolition and the production process also arranged both at home and abroad, its way generally is with discarded maturing fragmentation, rely on impact, frictional force in the shattering process to make discarded concrete become fritter, and mortar and coarse aggregate are separated from each other to a certain extent, then the coarse aggregate of separating is used to prepare regenerated aggregate concrete.But, there are some problems in this separation method, the one, be difficult to more fully separate between mortar and the coarse aggregate, and the coarse aggregate that has adhered to mortar when preparation regenerated coarse aggregate concrete since the big concrete that makes preparation of the water imbibition of mortar newly to mix service behaviour relatively poor, simultaneously in broken apart process often between the mortar of the mortar inside that adheres to, adhesion and coarse aggregate the interface produce a large amount of micro-cracks, make the regenerated aggregate concrete physical and mechanical property of preparation relatively poor, strength grade is low; The 2nd, the mortar of separating is often thrown aside as rubbish, be difficult to will be closely the fine aggregate of parcel and cement stone be separated from each other out respectively and be used.

Summary of the invention

At the problems referred to above, the object of the present invention is to provide a kind of method that coarse aggregate, fine aggregate and cement stone component in the discarded concrete are separated from each other, this method separative efficiency height, quality height.

To achieve these goals, technical scheme of the present invention is: the method that a kind of waste concrete component separates is characterized in that it comprises the steps:

1), the bulk discarded concrete that will remove impurity such as reinforcing bar, wooden unit is broken into the fritter of 10cm-30cm particle size with jaw crusher, and then become the 3cm-10cm size particles with bevel-type eccentrically weighted shaft crusher in crushing, to be difficult to irony impurity such as manual sorting's tiny reinforcing bar and iron nail with the electromagnetism magnetic separator de-ironing and remove, material particles;

2), material particles is heated to 250 ℃-350 ℃ with vertical oil burner, make it be chilled to normal temperature with wind-force again;

3), cooled material is sent in the middle of the ball mill, between the material particles, between material particles and the steel ball mutually under collision, the rubbing action, make to adhere to mortar and coarse aggregate is separated from each other, material time of staying in ball mill is 3-10min; Material goes out the mill back and with the 5mm vibratory sieve mortar particulate and the coarse aggregate that separates is separated from each other out;

4), the mortar particulate of separating is sent into wind again sweep and carry out grinding in the tube mill, the time of staying is 5-15min in wind is swept tube mill; Mortar particulate quartz sand fine aggregate and cement stone under abrasive action are separated from each other, and cement stone ground to form fine powder, under the wind-force effect, cement stone fine powder is discharged with the wind, collect with bag filter, quartz sand (being fine aggregate) is then discharged from the mill tail, realizes the separation between fine aggregate and the cement stone.

Principle of the present invention: at first, utilize the difference of aggregate and heat expansion coefficients of set cements, make in the middle of the discarded concrete particle between the aggregate and cement stone because thermal stress is concentrated and produced micro-crack at the interface weak area by heat treated, and make existing micro-crack extension; Secondly, the cyclic fatigue load that utilizes grinding to produce makes the further unstability development of micro-crack between aggregate and cement stone, and aggregate and cement stone are broken away from mutually, by sieving separating of realization coarse aggregate and mortar; At last, utilize the significant difference of fine aggregate and cement stone grindability, and the difference of both diameter of particle and density during combined grinding, adopt the mill inner ventilation technology, realize separating of fine aggregate and cement stone according to winnowing powder principle.

The invention provides the waste concrete component separation method that a kind of fragmentation, Low Temperature Heat Treatment, grinding fragmentation, screening, secondary grinding and winnowing powder combine; Beneficial effect of the present invention is: separative efficiency height, quality height.

The present invention has following characteristics:

1, the waste concrete component separation method that fragmentation, Low Temperature Heat Treatment, grinding and winnowing powder combine is proposed first.

2, this method has realized three kinds of topmost components in the discarded concrete: coarse aggregate, fine aggregate and cement stone high efficiency, high-quality disconnected from each other, and for this three kinds of components high added value regeneration separately provides necessary condition.

Description of drawings

Fig. 1 is a process chart of the present invention

The specific embodiment

In order to understand the present invention better, further illustrate content of the present invention below in conjunction with embodiment, but content of the present invention not only is confined to the following examples.

Embodiment 1:

As shown in Figure 1, certain cement concrete road is removed rebuilding, the discarded concrete that to produce a large amount of former strength grades be C30, the discarded concrete bulk is removed reinforcing bar, be transported to discarded concrete process for producing line after being broken into the fritter of 30cm particle size with jaw crusher at the scene behind the impurity such as earth, the discarded concrete fritter is broken into the particle of 7cm particle size with the eccentric disintegrating machine of bevel-type rotating shaft, with the electromagnetism magnetic separator de-ironing tiny irony impurity such as iron wire are removed, be heated to 250 ℃ with the minitype vertical type oil burner again, the quick cooled material of wind-force is sent in the middle of Φ 1200mm * 2400mm size small grinder then, material is time of staying 3min in mill, square hole screen with the 5mm aperture after material goes out to grind sieves processing, the realization coarse aggregate separates with the mortar particulate, the wind of again the mortar particulate of separating being sent into Φ 1200mm * 4500mm size is swept and is carried out grinding in the tube mill and handle, material is time of staying 10min in mill, levigate cement stone fine powder goes out mill with mill inner ventilation, collects with bag filter; And the most of particle of the quartz sand of difficult mill is bigger, is difficult to be suspended in the mill discharge with the wind in the air, can only discharge from the mill tail with the rotation of grinding machine, realizes being separated from each other of quartz sand fine aggregate and cement stone dust body.

Embodiment 2:

As shown in Figure 1, certain cement concrete bridge is removed, the discarded concrete that to produce a large amount of former strength grades be C50, the discarded concrete bulk is removed reinforcing bar, be transported to discarded concrete process for producing line after being broken into the fritter of 20cm particle size with jaw crusher at the scene behind the impurity such as wooden unit, the discarded concrete fritter is broken into the particle of 4cm particle size with the eccentric disintegrating machine of bevel-type rotating shaft, with the electromagnetism magnetic separator de-ironing tiny irony impurity such as iron wire are removed, be heated to 300 ℃ with the minitype vertical type oil burner again, the quick cooled material of wind-force is sent in the middle of Φ 1200mm * 2400mm size small grinder then, material is time of staying 5min in mill, square hole screen with the 5mm aperture after material goes out to grind sieves processing, the realization coarse aggregate separates with the mortar particulate, carrying out grinding in the mortar particulate of separating being sent into Φ 1200mm * 4500mm size again air swept mill handles, material is time of staying 12min in mill, levigate cement stone fine powder goes out mill with mill inner ventilation, collects with bag filter; And the most of particle of the quartz sand of difficult mill is bigger, is difficult to be suspended in the mill discharge with the wind in the air, can only discharge from the mill tail with the rotation of grinding machine, realizes being separated from each other of quartz sand fine aggregate and cement stone dust body.

Embodiment 3:

The method that a kind of waste concrete component separates, it comprises the steps:

1), the bulk discarded concrete that will remove impurity such as reinforcing bar, wooden unit is broken into the fritter of 10cm particle size with jaw crusher, and then become the 3cm size particles with bevel-type eccentrically weighted shaft crusher in crushing, to be difficult to irony impurity such as manual sorting's tiny reinforcing bar and iron nail with the electromagnetism magnetic separator de-ironing and remove, material particles;

2), material particles is heated to 350 ℃ with vertical oil burner, make it be chilled to normal temperature with wind-force again;

3), cooled material is sent in the middle of the ball mill, between the material particles, between material particles and the steel ball mutually under collision, the rubbing action, make to adhere to mortar and coarse aggregate is separated from each other, material time of staying in ball mill is 10min; Material goes out the mill back and with the 5mm vibratory sieve mortar particulate and the coarse aggregate that separates is separated from each other out;

4), the mortar particulate of separating is sent into wind again sweep and carry out grinding in the tube mill, the time of staying is 15min in wind is swept tube mill; Mortar particulate quartz sand fine aggregate and cement stone under abrasive action are separated from each other, and cement stone is ground to form fine powder, under the wind-force effect, cement stone fine powder is discharged with the wind, collect with bag filter, quartz sand is then discharged from the mill tail, realizes the separation between fine aggregate and the cement stone.

Claims

1. the method that waste concrete component separates is characterized in that it comprises the steps:

1), will remove bulk discarded concrete behind the impurity is broken into the 10cm-30cm particle size with jaw crusher fritter, and then become the 3cm-10cm size particles with bevel-type eccentrically weighted shaft crusher in crushing, remove irony impurity with the electromagnetism magnetic separator de-ironing, get material particles;

4), the mortar particulate of separating is sent into wind again sweep and carry out grinding in the tube mill, the time of staying is 5-15min in wind is swept tube mill; Mortar particulate quartz sand fine aggregate and cement stone under abrasive action are separated from each other, and cement stone is ground to form fine powder, under the wind-force effect, cement stone fine powder is discharged with the wind, collect with bag filter, quartz sand is then discharged from the mill tail, realizes the separation between fine aggregate and the cement stone.

2. the method that a kind of waste concrete component according to claim 1 separates, it is characterized in that: described ball mill is Φ 1200mm * 2400mm size small grinder; It is that the wind of Φ 1200mm * 4500mm size is swept tube mill that described wind is swept tube mill.