阅读说明：本技术 一种高性能人工轻骨料及其制备方法 (High-performance artificial lightweight aggregate and preparation method thereof ) 是由 张宏生 窦明岳 王光 于 2018-08-30 设计创作，主要内容包括：本发明提供了一种高性能人工轻骨料及其制备方法,所述人工轻骨料包括按质量份数计的下述组份：铸造旧砂500～1000份、铸造再生除尘灰500～1000份、膨润土50-500份、粉煤灰0-500份、高岭土50-500份和煤粉0-50份。该人工轻骨料具有密度低、吸水率低、强度高、保温、防火、耐久、抗震、吸音、利废等优点,以及易于预制、便于运输等特征。该法用铸造废灰及粉煤灰作为原料,对铸造过程中废弃的铸造旧砂除尘再生灰进行了有效地利用,避免了其大量堆放对土地及水资源造成的环境污染,同时降低了人工轻骨料的生产成本。(The invention provides a high-performance artificial lightweight aggregate and a preparation method thereof, wherein the artificial lightweight aggregate comprises the following components in parts by weight: 500-1000 parts of used foundry sand, 500-1000 parts of regenerated dedusting ash, 50-500 parts of bentonite, 0-500 parts of fly ash, 50-500 parts of kaolin and 0-50 parts of coal powder. The artificial lightweight aggregate has the advantages of low density, low water absorption, high strength, heat preservation, fire prevention, durability, earthquake resistance, sound absorption, waste utilization and the like, and has the characteristics of easy prefabrication, convenient transportation and the like. The method uses the casting waste ash and the fly ash as raw materials, effectively utilizes the casting used sand dedusting regeneration ash discarded in the casting process, avoids the environmental pollution to the land and water resources caused by the large-scale stacking of the casting used sand dedusting regeneration ash, and simultaneously reduces the production cost of the artificial lightweight aggregate.)

1. The high-performance artificial lightweight aggregate is characterized by comprising the following components in parts by weight:

2. the artificial lightweight aggregate according to claim 1, wherein the bentonite comprises Ca-based bentonite or/and Na-based bentonite.

3. The artificial lightweight aggregate according to claim 1, wherein the fly ash comprises primary ash or/and secondary ash.

4. The artificial lightweight aggregate according to claim 1, wherein the kaolin is metakaolin calcined at 600-800 ℃.

5. The artificial lightweight aggregate according to claim 1, wherein the artificial aggregate has a water absorption of 5.46 to 7.2% and a density of 956 to 1066kg/m³And the compressive strength is 14.25-18.6 MPa.

6. The method for preparing the high-performance artificial lightweight aggregate according to any one of claims 1 to 5, which comprises the following steps:

(1) preparing a mixed material:

ball-milling or crushing the components for 30-60min and mixing in proportion;

(2) granulation and maintenance:

granulating the mixed powder in a disc granulator, and then maintaining at constant temperature of 100-160 ℃ for 18-36 h;

(3) and (3) sintering:

sintering the cured pellets at 1100-1150 ℃ for 20-40 min to obtain the artificial aggregate.

7. The method according to claim 6, wherein the step (1) is carried out by stirring in a stirrer for 5 to 15 min.

8. The preparation method of claim 6, wherein the rotation speed of the disc granulator in the step (2) is 30-40 r/min; the diameter of the material ball is 5-8 mm.

9. The preparation method according to claim 6, characterized in that the pan granulator comprises a granulation disc (1) and a connecting shaft (2) connected to the granulation disc, the connecting shaft (2) is in transmission connection with an output shaft of a motor (3), a bracket (4) is fixedly connected to a bearing sleeved outside the connecting shaft (2), an O-shaped pad (5) with a triangular cross section is arranged in the granulation disc (1), and two side surfaces of the O-shaped pad (5) are respectively attached to the side surface and the bottom surface of the granulation disc (1); the cross section of the third surface of the O-shaped pad (5) is arc-shaped.

Technical Field

The invention relates to the field of recycling of solid wastes, in particular to an artificial aggregate prepared by using solid wastes as raw materials and a preparation method thereof.

Background

The regenerated fly ash of the used foundry sand is solid waste generated in the process of regenerating the used foundry sand by a thermal method. And roasting the used foundry sand in a high-temperature fluidized bed furnace at 700-900 ℃, and then generating a large amount of dust in the screening, vibrating, separating and regenerating processes, namely regenerated dedusting ash. The foundry sand mainly comprises silica sand and water glass, clay, resin and the like as auxiliary materials to form molding sand, so that the components of the reclaimed dedusting ash of the used foundry sand mainly comprise quartz, bentonite, clay and carbon with part of resin incompletely combusted, and a small amount of metal oxide is also contained. At present, the foundry does not have an effective treatment method for the part of solid waste, most of the foundry used sand regenerated dust is treated in a local stacking or landfill mode, so that a large amount of solid waste is buried underground for a long time, a large amount of occupied land can be caused, and the ecological environment pollution is caused.

The artificial light aggregate applied in the field of buildings at present mainly takes natural clay and shale artificial aggregate as main materials, and also comprises clay-fly ash and shale-fly ash artificial aggregate which are prepared by partially adding fly ash. With the attention of people on the protection of cultivated land and the protection of environment, the large-scale exploitation of natural sandstone, clay and shale is limited, the raw material cost of natural mineral resources is greatly increased, and the preparation of green building materials by taking solid wastes as main raw materials is the development direction of future building materials.

Therefore, a technical scheme for recycling the foundry used sand reclaimed dedusting ash solid waste is needed to solve the problem of environmental pollution in the prior art.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention aims to provide a method for preparing a light high-performance artificial lightweight aggregate from the regenerated dedusting ash of the foundry used sand, so that the solid waste of the regenerated dedusting ash of the foundry used sand is recycled, and the prepared artificial aggregate has the advantages of light weight, high strength, fire resistance, low water absorption, wear resistance and the like, and realizes a low-cost, environment-friendly and large-scale treatment approach for the regenerated waste ash of the foundry.

The technical scheme for realizing the purpose of the invention is as follows:

a high-performance artificial lightweight aggregate comprises the following components in parts by weight:

preferably, the bentonite comprises Ca-based bentonite or/and Na-based bentonite.

Preferably, the kaolin is metakaolin calcined at 600-800 ℃.

Preferably, the fly ash comprises primary ash or/and secondary ash.

Preferably, the artificial aggregate has the water absorption of 5.46-7.2%, the density of 956-1066 kg/m3 and the compressive strength of 14.25-18.6 MPa.

The preparation method of the high-performance artificial aggregate is characterized by comprising the following steps:

(1) preparing a mixed material:

ball-milling or crushing the components for 30-60min and mixing in proportion;

(2) granulation and maintenance:

granulating the mixed powder in a disc granulator, and then maintaining at constant temperature of 100-160 ℃ for 18-36 h;

(3) and (3) sintering:

sintering the cured pellets at 1100-1150 ℃ for 20-40 min to obtain the artificial aggregate.

Preferably, the step (1) is carried out for 5-15 min in a stirrer.

Preferably, the rotating speed of the disc granulator in the step (2) is 30-40 r/min; the diameter of the material ball is 5-8 mm.

Preferably, the disc granulator comprises a granulating disc (1) and a connecting shaft (2) connected to the granulating disc, the connecting shaft (2) is in transmission connection with an output shaft of a motor (3), a support (4) is fixedly connected to a bearing sleeved on the outer side of the connecting shaft (2), an O-shaped pad (5) with a triangular section is arranged in the granulating disc (1), and two side faces of the O-shaped pad (5) are respectively attached to the side face and the bottom face of the granulating disc (1); the cross section of the third surface of the O-shaped pad (5) is arc-shaped.

Compared with the closest prior art, the technical scheme provided by the invention has the following excellent effects:

1. the invention uses the casting used sand regenerated dedusting ash as the raw material of the artificial lightweight aggregate, effectively utilizes the casting used sand regenerated dedusting ash discarded in the casting process, avoids the environmental pollution caused by large stacking of the casting used sand regenerated dedusting ash to the land and water resources, and simultaneously reduces the production cost of the artificial lightweight aggregate.

2. The artificial lightweight aggregate prepared by the invention has excellent performance, has the advantages of low density, low water absorption, high strength and the like, and has the advantages of energy conservation, consumption reduction, great construction cost reduction and the like when being used in the fields of high-rise buildings, large-span bridge buildings and the like.

3. The disk granulator used in the preparation process can effectively prevent materials from being accumulated at the corners, granulation is more uniform, and after granulation is finished, the disk is convenient to clean, corrosion of the corners is prevented, and the service life of the disk is prolonged.

Drawings

Fig. 1 is a schematic view of a pan granulator used in the present invention.

FIG. 2 is an enlarged view of the structure of part A

Wherein: 1: a granulation disc; 2: a connecting shaft; 3: a motor; 4: a support; 5: o-shaped pad

Detailed Description

The following further describes specific embodiments of the present invention with reference to the following examples and drawings, but the present invention is not limited to these examples.