阅读说明：本技术 一种以铁尾矿、电石渣、钢渣为主原料制备的掺合料及其制备方法 (Admixture prepared by taking iron tailings, carbide slag and steel slag as main raw materials and preparation method thereof ) 是由 梁延秋 许世斌 夏举佩 李朴忠 于 2021-07-21 设计创作，主要内容包括：本发明涉及一种以铁尾矿、电石渣、钢渣为主原料制备的掺合料及其制备方法,属于固体废弃物资源化利用及建筑材料技术领域。该掺合料由活性材料与活性激发剂经混合、静压成型、煅烧、粉磨制得,掺合料由铁尾矿、电石渣、钢渣按干基质量比50～55：45～50：10～15组成,活性激发剂为盐激发剂和表面活性剂,盐激发剂由活性材料总质量的1～1.5%的硫酸钠和1.5～2.5%的硫酸钙组成,表面活性剂的添加量为活性材料总质量的0.1～0.3‰。本发明利用固体废弃物为原料、激发剂添加量较少,环保并利于掺合料的发展。同时,本发明的中热活化温度较低,生产成本低,并且工艺简单,达到了较高的经济效益。(The invention relates to an admixture prepared by taking iron tailings, carbide slag and steel slag as main raw materials and a preparation method thereof, belonging to the technical field of resource utilization of solid wastes and building materials. The admixture is prepared by mixing, static pressure forming, calcining and grinding an active material and an active excitant, wherein the admixture is prepared from iron tailings, carbide slag and steel slag according to a dry-basis mass ratio of 50-55: 45-50: 10-15, wherein the active activator is a salt activator and a surfactant, the salt activator is composed of 1-1.5% of sodium sulfate and 1.5-2.5% of calcium sulfate based on the total mass of the active material, and the addition amount of the surfactant is 0.1-0.3 per mill of the total mass of the active material. The invention uses solid waste as raw material, has less addition of excitant, is environment-friendly and is beneficial to the development of admixture. Meanwhile, the medium thermal activation temperature is lower, the production cost is low, the process is simple, and higher economic benefit is achieved.)

1. An admixture prepared by taking iron tailings, carbide slag and steel slag as main raw materials is characterized in that: the admixture is prepared from an active material and an active excitant, wherein the active material is prepared from iron tailings, carbide slag and steel slag according to a dry-basis mass ratio of 50-55: 45-50: 10-15, wherein the active activator is a salt activator and a surfactant, the salt activator is composed of 1-1.5% of sodium sulfate and 1.5-2.5% of calcium sulfate based on the total mass of the active material, and the addition amount of the surfactant is 0.1-0.3 per mill of the total mass of the active material.

2. The admixture of claim 1, wherein: the granularity of the iron tailings is 0.06-0.1 mm, the moisture content is less than or equal to 1%, the granularity of the carbide slag is 5-10 mm, the moisture content is less than or equal to 40%, the residue of the steel slag after being sieved by a 100-mesh sieve is less than or equal to 5%, and the moisture content is less than or equal to 1%.

3. The admixture of claim 1, wherein: the surfactant is sodium lignosulphonate or calcium lignosulphonate or sodium dodecyl sulfonate.

4. The preparation method of the admixture prepared by taking the iron tailings, the carbide slag and the steel slag as main raw materials according to claim 1 is characterized by comprising the following steps: the preparation method comprises the following specific steps:

(1) pretreatment of raw materials: respectively taking iron tailings, carbide slag and steel slag as raw materials, crushing and drying;

(2) and (3) static pressure forming: weighing the raw materials processed in the step (1) according to the mass ratio of the raw materials, uniformly mixing, and then pressing and forming to obtain the porous building block;

(3) and (3) airing: airing the porous building block prepared in the step (2) to enable the moisture content of the porous building block to be less than 5%;

(4) and (3) calcining: calcining the air-dried porous building block in the step (3) at 1000-1200 ℃ for 2-4 h, taking out, and naturally cooling to below 100 ℃;

(5) grinding: adding 1-1.5% of sodium sulfate, 1.5-2.5% of calcium sulfate and 0.1-E in total mass of active materials into the porous building block treated in the step (4)0.3 per mill of surfactant, and grinding to specific surface area of 500 +/-20 m²And/kg, thus obtaining the admixture.

5. The method of claim 4, wherein: in the step (1), the granularity of the iron tailings is 0.06-0.1 mm, the moisture content is less than or equal to 1%, the granularity of the carbide slag is 5-10 mm, the moisture content is less than or equal to 40%, the residue of the steel slag after being sieved by a 100-mesh sieve is less than or equal to 5%, and the moisture content is less than or equal to 1%.

6. The method of claim 4, wherein: and (3) in the step (2), carrying out static pressure for 5-10 s under the pressure of 0.2-0.5 MPa.

7. The method of claim 4, wherein: and (3) airing at 10-60 ℃.

8. The method of claim 4, wherein: and (4) cooling at 5-35 ℃.

9. The method of claim 4, wherein: in the step (5), the surfactant is sodium lignosulfonate or calcium lignosulfonate or sodium dodecyl sulfate.

Technical Field

The invention relates to an admixture prepared by taking iron tailings, carbide slag and steel slag as main raw materials and a preparation method thereof, belonging to the technical field of resource utilization of solid wastes and building materials.

Background

The admixture is inorganic mineral fine powder which can replace part of cement as cementing material and change the performance of fresh concrete and hardened concrete when preparing concrete. Foreign countries refer to such fine mineral powders as supplementary cementitious materials. At present, the admixture becomes an indispensable sixth component of high-performance concrete, and is a material mainly containing one or more oxides of silicon, aluminum and calcium. At present, the research technology of the admixture prepared from industrial solid wastes such as blast furnace slag, fly ash and silica fume is mature, most of the technology mainly comprises the addition of additives, the variety of the excitant is less, the price is relatively high, and the same excitant is difficult to use when the admixtures of different systems are added, so that the preparation technology of the admixture is difficult to popularize.

The iron tailings are used as the rest after the raw iron ore is crushed, screened, ground, classified, reselected, floated or cyanided to select useful metals such as iron. Besides a small amount of metal, most of the iron tailings are gangue minerals, and a small amount of the iron tailings are difficult to utilize after iron is selected again. The carbide slag is waste slag which is obtained by hydrolyzing carbide to obtain acetylene gas and takes calcium hydroxide as a main component, belongs to national II-class general industrial solid wastes, occupies a large amount of land during treatment, needs to be treated by an anti-seepage measure, and is high in cost. The building materials made of the carbide slag are utilized by enterprises, but the profit is slightly insufficient, and the industry needs to be innovated. The impurity waste slag generated in the steel-making process of the steel slag converter has the same mineral phase as cement, but the temperature is high in the slagging process, the activity of most mineral phases is low, the content of free calcium oxide in the steel slag is high, the free calcium oxide is difficult to be utilized in a large amount, and the slag is industrial solid waste which is difficult to treat at present.

The iron tailings, the carbide slag and the steel slag all contain materials mainly containing one or more oxides of silicon, aluminum and calcium, are difficult to prepare into cement clinker, but are suitable for preparing into active admixture. China brings comprehensive utilization of resources into ecological civilization construction overall layout, and comprehensive utilization of solid wastes is increased. But the utilization rate is still low, and the problems of large solid waste yield, insufficient utilization, low product added value and the like are still faced in China. The comprehensive utilization rate of bulk solid wastes is up to 60% in 2025. Therefore, the method utilizes the iron tailings, the carbide slag and the steel slag as raw materials to produce the active admixture through thermal activation, not only accords with the national environmental protection policy, but also solves a series of hazards caused by dangerous solid wastes from the source, and the method has simple operation process and can bring good economic benefit.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides an admixture prepared by taking iron tailings, carbide slag and steel slag as main raw materials and a preparation method thereof, wherein the iron tailings, the carbide slag and the steel slag are taken as the raw materials to be scientifically matched, and the admixture is prepared by thermal activation, so that the utilization of solid wastes is realized, the cost is low, and the environment is protected; the process is simple and easy to operate.

In order to solve the technical problems, the invention provides an admixture prepared by taking iron tailings, carbide slag and steel slag as main raw materials, wherein the admixture is prepared from an active material and an activity excitant, and the admixture is prepared from the iron tailings, the carbide slag and the steel slag according to a dry-basis mass ratio of 50-55: 45-50: 10-15, wherein the active activator is a salt activator and a surfactant, the salt activator is composed of 1-1.5% of sodium sulfate and 1.5-2.5% of calcium sulfate based on the total mass of the active material, and the addition amount of the surfactant is 0.1-0.3 per mill of the total mass of the active material.

The particle size of the iron tailings is 0.06-0.1 mm, the moisture content is less than or equal to 1%, the moisture content of the carbide slag is less than or equal to 40%, the particle size is 5-10 mm, the residue of the steel slag after passing through a 100-mesh sieve is less than or equal to 5%, and the moisture content is less than or equal to 1%.

The surfactant is sodium lignosulphonate or calcium lignosulphonate or sodium dodecyl sulfonate.

The preparation method of the admixture prepared by taking the iron tailings, the carbide slag and the steel slag as main raw materials comprises the following specific preparation steps:

(1) pretreatment of raw materials: respectively taking iron tailings, carbide slag and steel slag as raw materials, crushing and drying;

(2) and (3) static pressure forming: respectively weighing the raw materials treated in the step (1) according to the mass ratio of the raw materials, uniformly mixing, putting into a forming groove, and carrying out static pressure for 5-10 s under the pressure of 0.2-0.5 MPa to obtain a porous building block;

(3) and (3) airing: naturally airing the porous building block prepared in the step (2) at 10-60 ℃ to ensure that the moisture content of the porous building block is less than 5%;

(4) and (3) calcining: calcining the air-dried porous building block in the step (3) at 1000-1200 ℃ for 2-4 h, taking out, and naturally cooling to below 100 ℃ at 5-35 ℃;

(5) grinding: adding 1-1.5% of sodium sulfate, 1.5-2.5% of calcium sulfate and 0.1-0.3% of surfactant by mass of the total mass of the active materials into the porous building block treated in the step (4), and grinding the mixture to a specific surface area of 500 +/-20 m²And/kg, thus obtaining the admixture.

In the step (1), the granularity of the iron tailings is 0.06-0.1 mm, the moisture content is less than or equal to 1%, the moisture content of the carbide slag is less than or equal to 40%, the granularity of the carbide slag is 5-10 mm, the granularity of the steel slag is less than or equal to 5% through a 100-mesh sieve, and the moisture content of the steel slag is less than or equal to 1%.

The surfactant is sodium lignosulfonate or calcium lignosulfonate or sodium dodecyl sulfate.

The admixture used in the invention meets the requirements of various levels of active admixtures in the GB/T51003-2014 regulations.

In the invention, the iron tailings, the carbide slag and the steel slag can be selected at will, and the properties, the components and the contents of the iron tailings, the carbide slag and the steel slag are not required.

The admixture prepared by the invention uses solid waste as raw materials, the raw materials are scientifically matched, steel slag is used as a mineralizer and a crystal nucleus agent, and carbide slag slurry is used as a bonding agent, so that the product performance is stable; in addition, the addition amount of the excitant is small in the preparation process, and the added sodium sulfate and calcium sulfate are relatively low in price, so that the development of the admixture is facilitated. Meanwhile, the medium thermal activation temperature is lower, the production cost is low, the process is simple, and higher economic benefit is achieved.

Drawings

FIG. 1 is a schematic process flow diagram of the present invention.

Detailed Description

The following further describes the embodiments of the present invention in detail. The techniques or products not mentioned in the examples are all conventional products which are available in the prior art or can be obtained by purchase.

Example 1: as shown in figure 1, the admixture prepared by taking the iron tailings, the carbide slag and the steel slag as main raw materials is prepared from an active material and an activity excitant, and the admixture is prepared from the iron tailings, the carbide slag and the steel slag according to a dry-basis mass ratio of 50: 50: 10, the active excitant is a salt excitant and a surfactant, the salt excitant is composed of 1% of sodium sulfate and 2.5% of calcium sulfate of the total mass of the active material, and the addition amount of the surfactant is 0.2 per mill of calcium lignosulphonate of the total mass of the active material.

The granularity of the iron tailings is 0.06mm, the moisture content is 0.8%, the moisture content of the carbide slag is 35%, the granularity is 10mm, and the granularity of the steel slag is 3% and 1% after passing through a 100-square-hole sieve. The components and contents of the three raw materials are shown in the following table:

the preparation method of the admixture prepared by taking the iron tailings, the carbide slag and the steel slag as main raw materials comprises the following specific preparation steps:

(1) pretreatment of raw materials: respectively taking iron tailings, carbide slag and steel slag as raw materials, crushing and drying;

(2) and (3) static pressure forming: respectively weighing the raw materials treated in the step (1) according to the mass ratio of the raw materials, uniformly mixing, putting into a forming groove, and carrying out static pressure for 10s under the pressure of 0.2MPa to obtain a porous building block;

(3) and (3) airing: airing the porous building block prepared in the step (2) at 10 ℃ until the water content of the porous building block is 5%;

(4) and (3) calcining: calcining the air-dried porous building block in the step (3) at 1200 ℃ for 3h, and naturally cooling to 85 ℃ at 28 ℃;

(5) grinding: and (4) simultaneously adding 1% of sodium sulfate, 2.5% of calcium sulfate and 0.2 per mill of calcium lignosulfonate of the total mass of the active materials into the porous building blocks treated in the step (4), and then grinding the porous building blocks until the specific surface area is 510 square meters per kg, thus obtaining the admixture.

In the step (1), the granularity of the iron tailings is 0.06mm, the moisture content is 0.8%, the moisture content of the carbide slag is 35%, the granularity of the carbide slag is 10mm, and the granularity of the steel slag is 3% and 1% of the water content of the steel slag passing through a 100-square-hole sieve.

The admixture used in the invention meets the requirement of an S95-grade active admixture in GB/T51003-2014 specification.

The admixture prepared by the invention replaces 50% of P.I 42.5 cement to prepare a mortar test piece with the size of 40 multiplied by 160mm, and the physical property detection is carried out. The mortar test piece added with the admixture is a tested test piece, and the mortar test piece meets the technical indexes of S95-grade admixture in GB/T51003-2014 standard, and is shown in the following table 1:

example 2: as shown in figure 1, the iron tailings, the carbide slag and the steel slag-based admixture are prepared from an active material and an active excitant, and the admixture is prepared from the iron tailings, the carbide slag and the steel slag according to a dry-basis mass ratio of 52: 48: 15, the active excitant is a salt excitant and a surfactant, the salt excitant is composed of sodium sulfate accounting for 1.5 percent of the total mass of the active material and calcium sulfate accounting for 2 percent of the total mass of the active material, and the addition amount of the surfactant is 0.1 per mill of sodium dodecyl sulfate accounting for the total mass of the active material.

The granularity of the iron tailings is 0.1mm, the moisture content is 0.7%, the moisture content of the carbide slag is 33%, the granularity is 5mm, and the granularity of the steel slag is 5% and the moisture content is 0.9% after passing through a 100-square-hole sieve. The components and contents of the three raw materials are shown in the following table:

the preparation method of the admixture prepared by taking the iron tailings, the carbide slag and the steel slag as main raw materials comprises the following specific preparation steps:

(1) pretreatment of raw materials: respectively taking iron tailings, carbide slag and steel slag as raw materials, crushing and drying;

(2) and (3) static pressure forming: respectively weighing the raw materials treated in the step (1) according to the mass ratio of the raw materials, uniformly mixing, putting into a forming groove, and carrying out static pressure for 8s under the pressure of 0.3MPa to obtain a porous building block;

(3) and (3) airing: naturally airing the porous building block prepared in the step (2) at 35 ℃ to ensure that the water content of the porous building block is 4%;

(4) and (3) calcining: calcining the air-dried porous building block in the step (3) at 1000 ℃ for 4h, and naturally cooling to 100 ℃ at 35 ℃;

(5) grinding: and (3) adding 1.5 percent of sodium sulfate, 2 percent of calcium sulfate and 0.1 per mill of sodium dodecyl sulfate of the total mass of the active materials into the porous building block treated in the step (4), and then grinding the porous building block to a specific surface area of 480 square meters per kilogram to obtain the admixture.

In the step (1), the granularity of the iron tailings is 0.1mm, the moisture content is 0.7%, the moisture content of the carbide slag is 33%, the granularity of the carbide slag is 5mm, and the granularity of the steel slag is 5% and the moisture content of the steel slag is 0.9% after passing through a 100-square-hole sieve.

The admixture used in the invention meets the requirements of various levels of active admixtures in the GB/T51003-2014 regulations.

The admixture prepared by the invention replaces 50% of P.I 42.5 cement to prepare a mortar test piece with the size of 40 multiplied by 160mm, and the physical property detection is carried out, wherein the mortar test piece added with the admixture of the invention is a tested test piece, which accords with the technical index of S75 grade admixture in GB/T51003-2014 standard, and is shown in the following table 2:

example 3: as shown in figure 1, the iron tailings, the carbide slag and the steel slag-based admixture are prepared from an active material and an active excitant, and the admixture is prepared from the iron tailings, the carbide slag and the steel slag according to a dry-basis mass ratio of 53: 47: 11, the active excitant is a salt excitant and a surfactant, the salt excitant is composed of 1.1 percent of sodium sulfate and 1.8 percent of calcium sulfate of the total mass of the active material, and the addition amount of the surfactant is 0.15 per mill of calcium lignosulfonate powder of the total mass of the active material.

The granularity of the iron tailings is 0.08mm, the moisture content is 1%, the moisture content of the carbide slag is 38%, the granularity is 8mm, and the granularity of the steel slag is sieved by a 100-square-hole sieve, the balance is 4%, and the moisture content is 0.7%. The components and contents of the three raw materials are shown in the following table:

the preparation method of the admixture prepared by taking the iron tailings, the carbide slag and the steel slag as main raw materials comprises the following specific preparation steps:

(1) pretreatment of raw materials: respectively taking iron tailings, carbide slag and steel slag as raw materials, crushing and drying;

(2) and (3) static pressure forming: respectively weighing the raw materials treated in the step (1) according to the mass ratio of the raw materials, uniformly mixing, putting into a forming groove, and carrying out static pressure for 5s under the pressure of 0.5MPa to obtain a porous building block;

(3) and (3) airing: naturally airing the porous building block prepared in the step (2) at 60 ℃ to ensure that the water content of the porous building block is 2%;

(4) and (3) calcining: calcining the air-dried porous building block in the step (3) at 1150 ℃ for 2.5h, and naturally cooling to 55 ℃ at 16 ℃;

(5) grinding: and (3) adding 1.1 percent of sodium sulfate and 1.8 percent of calcium sulfate in the total mass of the active material into the porous building block treated in the step (4), and grinding the porous building block into calcium lignosulfonate powder with the specific surface area of 500 square meters per kg after 0.15 per mill of the total mass of the active material, thereby obtaining the admixture.

In the step (1), the granularity of the iron tailings is 0.08mm, the moisture content is 1%, the moisture content of the carbide slag is 38%, the granularity of the carbide slag is 8mm, and the granularity of the steel slag is 4% and the moisture content of the steel slag is 0.7% after passing through a 100-square-hole sieve.

The admixture used in the invention meets the requirement of an S85-grade active admixture in GB/T51003-2014 specification.

The admixture prepared by the invention replaces 50% of P.I 42.5 cement to prepare a mortar test piece with the size of 40 multiplied by 160mm, and the physical property detection is carried out, wherein the mortar test piece added with the admixture of the invention is a tested test piece, which accords with the technical index of S85 grade admixture in GB/T51003-2014 standard, and is shown in the following table 3:

example 4: as shown in figure 1, the iron tailings, the carbide slag and the steel slag-based admixture are prepared from active materials and active excitants, and the admixture is prepared from the iron tailings, the carbide slag and the steel slag according to a dry-basis mass ratio of 55: 45: 12, the active excitant is a salt excitant and a surfactant, the salt excitant is composed of 1.3 percent of sodium sulfate and 1.5 percent of calcium sulfate of the total mass of the active material, and the addition amount of the surfactant is 0.3 per mill of sodium lignosulfonate of the total mass of the active material.

The granularity of the iron tailings is 0.09mm, the moisture content is 0.5%, the moisture content of the carbide slag is 40%, the granularity is 7mm, and the granularity of the steel slag is 4.5% and the moisture content is 0.6% after passing through a 100-square-hole sieve. The components and contents of the three raw materials are shown in the following table:

the preparation method of the admixture prepared by taking the iron tailings, the carbide slag and the steel slag as main raw materials comprises the following specific preparation steps:

(1) pretreatment of raw materials: respectively taking iron tailings, carbide slag and steel slag as raw materials, crushing and drying;

(2) and (3) static pressure forming: respectively weighing the raw materials treated in the step (1) according to the mass ratio of the raw materials, uniformly mixing, putting into a forming groove, and carrying out static pressure for 6s under the pressure of 0.4MPa to obtain a porous building block;

(3) and (3) airing: naturally airing the porous building block prepared in the step (2) at 50 ℃ to ensure that the water content of the porous building block is 1%;

(4) and (3) calcining: calcining the air-dried porous building block in the step (3) at 1100 ℃ for 2h, and naturally cooling to 25 ℃ at 5 ℃;

(5) grinding: and (3) adding sodium sulfate accounting for 1.3 percent of the total mass of the active materials, calcium sulfate accounting for 1.5 percent of the total mass of the active materials and sodium lignosulfonate accounting for 0.3 per thousand of the total mass of the active materials into the porous building block treated in the step (4), and then grinding the porous building block to a specific surface area of 520 square meters per kg, thus obtaining the admixture.

The granularity of the iron tailings is 0.09mm, the moisture content is 0.5%, the moisture content of the carbide slag is 40%, the granularity is 7mm, and the granularity of the steel slag is 4.5% and the moisture content is 0.6% after passing through a 100-square-hole sieve.

The admixture used in the invention meets the requirement of 105-grade active admixture in GB/T51003-2014 specification.

The admixture prepared by the invention replaces 50% of P.I 42.5 cement to prepare a mortar test piece with the size of 40 multiplied by 160mm, the cement mortar test piece is used as a comparison test piece, the mortar test piece added with the admixture of the invention is a tested test piece, and the mortar test piece meets the technical index of S105 grade admixture in GB/T51003-:

while the invention has been described with reference to specific embodiments, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention.