阅读说明：本技术 一种高硅质脱硫铜尾矿微粉及其制备和在phc管桩生产中的应用 (High-siliceous desulfurized copper tailing micro powder, preparation thereof and application thereof in PHC pipe pile production ) 是由 鲁亚 刘松柏 漆江锋 曹志雄 于 2020-07-31 设计创作，主要内容包括：本发明提供一种脱硫铜尾矿微粉,其中SO<Sub>3</Sub>含量<1.5%、水含量<15%、二氧化硅含量≥65%、比表面积为450-550m<Sup>2</Sup>/kg、各粒径间重量比例为：10-75μm:5-10μm:2-5μm:＜2μm=20-35:20-30:15-25:15-25。本发明所述的脱硫铜尾矿微粉性能优异,具有高硅含量。本发明还提供所述脱硫铜尾矿微粉的制备方法和作为硅质原料在PHC管桩生产中的应用。本发明的脱硫铜尾矿微粉应用于PHC管桩生产时,能够高比例替代天然硅质原料,而且可以有效解决铜尾矿堆存产生环境、安全等问题,还能有效降低PHC管桩生产成本。(The invention provides a desulfurized copper tailing micro powder, wherein SO 3 Content (wt.)<1.5% water content<15 percent, the content of silicon dioxide is more than or equal to 65 percent, the specific surface area is 450-550m 2 Kg, weight ratio among particle diameters: 5-10 μm:2-5 μm < 2 μm =20-35:20-30:15-25: 15-25. The desulfurized copper tailing micro powder disclosed by the invention is excellent in performance and high in silicon content. The invention also provides a preparation method of the desulfurized copper tailing micro powder and application of the desulfurized copper tailing micro powder as a siliceous raw material in PHC tubular pile production. The desulfurized copper tailing micropowder can replace natural siliceous raw materials in a high proportion when being applied to PHC tubular pile production, and can effectively solve the problem of environment caused by copper tailing stockpiling and ensure safetyThe production cost of the PHC tubular pile can be effectively reduced.)

1. The desulfurization copper tailing micro powder comprises SO in the desulfurization copper tailing micro powder according to weight percentage₃Content (wt.)<1.5% (preferably)<0.85%), water content<15% (preferred)<13%), a silica content of 65% or more (preferably 68% or more), a specific surface area of 450-²/kg (preferably 480-500 m)²/kg); the weight ratio among the particle sizes in the desulfurized copper tailing micro powder is as follows: 5-10 μm:2-5 μm < 2 μm =20-35:20-30:15-25: 15-25.

2. The desulfurized copper tailing micropowder of claim 1, wherein the content of chloride ions in the desulfurized copper tailing micropowder is less than or equal to 0.06 percent by weight; more preferably 0.01% or less.

3. The desulfurized copper tailing micropowder of claim 1, wherein the weight ratio among the particle sizes in the desulfurized copper tailing micropowder is: 5-10 μm:2-5 μm < 2 μm = 30-33: 20-22: 21-25: 24-25.

4. The desulfurized copper tailing micropowder of claim 1, wherein the desulfurized copper tailing micropowder is prepared by the following method: firstly, the copper tailings are floated and desulfurized to SO₃The content is lower than 1.5 percent, then the desulfurized copper tailings are subjected to filter pressing or filtration dehydration until the water content is lower than 15 percent, and the desulfurized and dehydrated copper tailings are ground into 550m with the specific surface area of 450-²The copper tailing micro powder is/kg, and finally, the grading is adjusted to ensure that the weight ratio among the particle sizes in the micro powder is as follows: 5-10 μm:2-5 μm < 2 μm =20-35:20-30:15-25: 15-25.

5. A process for preparing the desulfurized copper tailings micropowder of claim 1 comprising the steps of:

1) the copper tailings are subjected to flotation and desulfurization treatment to SO₃The content is lower than 1.5 percent, and the desulfurized copper tailing powder is obtained;

2) carrying out filter pressing or filter dehydration on the desulfurized copper tailing powder obtained in the step 1) until the water content is lower than 15%, thus obtaining desulfurized dehydrated copper tailing powder;

3) the desulfurization and dehydration copper tailing powder obtained in the step 2) is ground in a vertical grinding mode to reach the specific surface area of 450-550m²Per kg, obtaining the desulfurized and dehydrated copper tailing micro powder;

4) the grading is adjusted to ensure that the weight ratio among the particle sizes in the micro powder is as follows: 5-10 μm:2-5 μm < 2 μm =20-35:20-30:15-25: 15-25.

6. The application of the desulfurized copper tailings micropowder of claim 1 in PHC tubular pile production.

7. The use of claim 6, wherein: the application is that the desulfurized copper tailing micropowder is used as a siliceous raw material for PHC tubular pile production.

8. A raw material composition for producing PHC tubular piles comprises the following components in parts by weight:

cement: 200-350

Silica sand powder: 0-60

The desulfurized copper tailings micropowder of claim 1: 60-150

Silica fume or mineral powder: 0-15

Sand: 600-900

Stone: 1000-1400

Polycarboxylic acid water reducing agent: 5-20

Additive: 0 to 5; the additive is selected from any one of or the combination of two of a synergist and a gel reducer.

9. A raw material composition for producing PHC tubular piles comprises the following components in parts by weight:

cement: 270-320

Silica sand powder: 30

The desulfurized copper tailings micropowder of claim 1: 90-130

Silica fume or mineral powder: 5

Sand: 640-820

Stone: 1160-1370

Polycarboxylic acid water reducing agent: 9-13

Additive: 2.5-3.5; the additive is selected from any one of or the combination of two of a synergist and a gel reducer.

10. A PHC pile, which is obtained by mixing, molding and autoclaving the raw material composition according to claim 8 or 9 and water.

Technical Field

The invention relates to the field of building materials, in particular to high-silicon desulfurized copper tailing micro powder, preparation thereof and application thereof in PHC tubular pile production.

Background

High-strength prestressed concrete pipe piles (referred to as "PHC pipe piles") are in recent yearsThe high-strength concrete product which is developed quickly and applied widely has the advantages of high concrete strength grade, large bearing capacity, good impact resistance and bending resistance, high construction speed and the like, and is widely applied to basic engineering of industrial and civil buildings, railways, roads, bridges, ports, wharfs, municipal administration and large-scale equipment. The PHC tubular pile is maintained in an autoclaved curing mode by adopting a centrifugal forming process, the concrete strength grade is C80, and the autoclaved curing is an inert admixture, so that the application prospect is widened, and the cost is reduced. Because the activity of the inert admixtures is sufficiently activated under the conditions of high temperature and high pressure. Particularly, in the case of an inert substance such as quartz, it is impossible to react with Ca (OH) in cement at ordinary temperature₂Reacted but under autoclave conditions, SiO₂Can react with Ca (OH)₂Can react chemically to produce tobermorite with high strength. Therefore, a large amount of siliceous materials such as silica sand powder are generally used in raw materials for producing PHC tubular piles, and the silica sand powder is generally used after being ground by sandy raw materials (generally, natural river sand, lake sand, mountain sand, machine-made sand and the like), so that the production cost is high and the quality is not stable due to the lack of natural resources at present.

Statistical data from the national institute of economic resources indicate that: from 1949 to 2007, the accumulated discharge amount of the copper tailings in China is up to 24 hundred million tons, about 3 hundred million tons are newly added every year, the main disposal mode of the copper tailings at present is that after being discharged, tailing pulp is piled up in a manually built tailing pond, and long-term piling up will pollute the ecological environment, occupy land resources, cause potential safety hazards in manufacturing and cause resource waste. The copper tailings are fine powder, SiO, left after the copper ores are crushed, ground and selected₂High content and good grindability.

Disclosure of Invention

The invention aims to: by utilizing the characteristics of high silicon dioxide content, good grindability and the like of the waste copper tailings, the copper tailings are subjected to desulfurization and dehydration process pretreatment, then are dried, ground and sorted (gradation adjustment), and are applied to the PHC tubular pile production instead of natural siliceous raw materials, so that the problems of environment, safety and the like caused by copper tailings accumulation can be effectively solved, and the production cost of the PHC tubular pile is effectively reduced.

The above object of the present invention is achieved by the following technical solutions:

firstly, providing the desulfurized copper tailing micro powder, wherein SO is contained in the desulfurized copper tailing micro powder according to weight percentage₃Content (wt.)<1.5%, water content<15 percent, the content of silicon dioxide is more than or equal to 65 percent, the specific surface area is 450-550m²Per kg; the weight ratio among the particle sizes in the desulfurized copper tailing micro powder is as follows: 5-10 μm:2-5 μm < 2 μm =20-35:20-30:15-25: 15-25.

In the preferable scheme of the invention, the SO in the desulfurized copper tailing micro powder is calculated by weight percentage₃Content (wt.)<0.85%。

In the preferable scheme of the invention, the water content in the desulfurized copper tailing micro powder is less than 13 percent by weight.

In the preferred scheme of the invention, the content of silicon dioxide in the desulfurized copper tailing micro powder is more than or equal to 68 percent in percentage by weight.

In the preferable scheme of the invention, the specific surface area of the desulfurized copper tailing micro powder is 480-500m²/kg。

In the preferable scheme of the invention, the content of chloride ions in the desulfurized copper tailing micro powder is less than or equal to 0.06 percent by weight; more preferably 0.01% or less.

In the preferable scheme of the invention, the weight ratio of the grain diameters in the desulfurized copper tailing micro powder is as follows: 5-10 μm:2-5 μm < 2 μm = 30-33: 20-22: 21-25: 24-25.

In the preferable scheme of the invention, the desulfurized copper tailing micro powder is prepared according to the following method: firstly, the copper tailings are floated and desulfurized to SO₃The content is lower than 1.5 percent, then the desulfurized copper tailings are subjected to filter pressing or filtration dehydration until the water content is lower than 15 percent, and the desulfurized and dehydrated copper tailings are ground into 550m with the specific surface area of 450-²The copper tailing micro powder is/kg, and finally, the grading is adjusted to ensure that the weight ratio among the particle sizes in the micro powder is as follows: 5-10 μm:2-5 μm < 2 μm =20-35:20-30:15-25: 15-25.

On the basis, the invention also provides a method for preparing the desulfurized copper tailing micro powder, which comprises the following steps:

1) the copper tailings are subjected to flotation and desulfurization treatment to SO₃The content is lower than 1.5 percent, and the desulfurized copper tailing powder is obtained;

2) carrying out filter pressing or filter dehydration on the desulfurized copper tailing powder obtained in the step 1) until the water content is lower than 15%, thus obtaining desulfurized dehydrated copper tailing powder;

3) the desulfurization and dehydration copper tailing powder obtained in the step 2) is ground in a vertical grinding mode to reach the specific surface area of 450-550m²Per kg, obtaining the desulfurized and dehydrated copper tailing micro powder;

4) the grading is adjusted to ensure that the weight ratio among the particle sizes in the micro powder is as follows: 5-10 μm:2-5 μm < 2 μm =20-35:20-30:15-25: 15-25.

In addition, the invention also provides application of the desulfurized copper tailing micro powder in PHC pipe pile production.

The application of the invention is that the desulfurized copper tailing micropowder is used as a siliceous raw material for producing PHC tubular piles.

Based on the application, the invention also provides a raw material composition for producing the PHC tubular pile, which comprises the following components in parts by weight:

cement: 200-350

Silica sand powder: 0-60

The invention relates to desulfurized copper tailing micro powder which comprises the following components in percentage by weight: 60-150

Silica fume or mineral powder: 0-15

Sand: 600-900

Stone: 1000-1400

Polycarboxylic acid water reducing agent: 5-20

Additives (synergists, gel reducing agents, etc.): 0-5.

In the preferred scheme of the invention, the raw material composition for producing the PHC tubular pile comprises the following components in parts by weight:

cement: 270-320

Silica sand powder: 30

The invention relates to desulfurized copper tailing micro powder which comprises the following components in percentage by weight: 90-130

Silica fume or mineral powder: 5

Sand: 640-820

Stone: 1160-1370

Polycarboxylic acid water reducing agent: 9-13

Additives (synergists, gel reducing agents, etc.): 2.5-3.5.

When the raw material composition is used for producing the PHC tubular pile, the raw material composition in the proportion is mixed into slurry according to a conventional method by a water-to-cement ratio of 0.20-0.35 (preferably the water-to-cement ratio of 0.22-0.28), and then the slurry is subjected to conventional forming and autoclaved curing, wherein the autoclave system is at a pressure of 1-1.2MPa and a temperature of 180-.

Compared with the prior art, the method utilizes the characteristics of high silicon dioxide content, good grindability and the like of the waste copper tailings, and the obtained desulfurized copper tailings micropowder has excellent performance and high silicon content after the copper tailings are subjected to desulfurization, dehydration drying, grinding and sorting (grading adjustment), can replace natural siliceous raw materials at a high ratio and be applied to PHC tubular pile production, can effectively solve the problems of environment, safety and the like caused by copper tailings stockpiling, and can effectively reduce the production cost of the PHC tubular pile.

Detailed Description