阅读说明：本技术 渣铁分离促进剂及其制备方法和使用方法 (Slag iron separation accelerant and preparation method and use method thereof ) 是由 肖军 宋兵 李凯茂 于 2020-07-02 设计创作，主要内容包括：本发明属于钛渣冶炼技术领域,具体涉及渣铁分离促进剂及其制备方法和使用方法。本发明渣铁分离促进剂,按质量百分比计,由铁粉70～90％、焦粉5～15％、氧化镁粉2～8％、粘结剂1～5％、水1～5％制成。本发明渣铁分离促进剂用于钛渣冶炼过程中的渣铁分离,可有效缩短渣铁分离时间、降低渣中夹铁比例、降低出铁温度。(The invention belongs to the technical field of titanium slag smelting, and particularly relates to a slag-iron separation promoter as well as a preparation method and a use method thereof. The slag-iron separation accelerant is prepared from 70-90% of iron powder, 5-15% of coke powder, 2-8% of magnesium oxide powder, 1-5% of a binder and 1-5% of water by mass percent. The slag-iron separation accelerant is used for slag-iron separation in the titanium slag smelting process, and can effectively shorten the slag-iron separation time, reduce the iron inclusion proportion in slag and reduce the tapping temperature.)

1. The slag-iron separation accelerant is characterized in that: the iron powder is prepared from 70-90% of iron powder, 5-15% of coke powder, 2-8% of magnesium oxide powder, 1-5% of binder and 1-5% of water by mass percentage.

2. The slag iron separation accelerator according to claim 1, wherein: the iron powder contains more than 90% of metallic iron and 1-3% of C; the grain diameter is less than or equal to 0.3mm and is more than 95 percent.

3. The slag iron separation accelerator according to claim 1 or 2, wherein: the iron powder is obtained by ball milling by using by-products generated in the titanium slag crushing process, such as iron particles or iron wires and other iron wastes, as basic raw materials.

4. The slag iron separation accelerator according to claim 1, wherein: the content of C in the coke powder is more than 80 percent, the volatile component is less than 5 percent, and the ash content is less than 20 percent; the grain diameter is less than 1mm and is more than 90 percent.

5. The slag iron separation accelerator according to claim 1 or 4, wherein: the coke powder is obtained by ball milling of fly ash or blocky coke produced by coking.

6. The slag iron separation accelerator according to claim 1, wherein: the MgO content in the magnesium oxide powder is more than 90 percent.

7. The slag iron separation accelerator according to claim 1, wherein: the binder is a solid organic binder.

8. The preparation method of the slag-iron separation accelerant is characterized by comprising the following steps: the method comprises the following steps: and fully and uniformly mixing iron powder, coke powder, magnesium oxide powder, a binder and water to obtain a mixture, then pressing the mixture into pellets, and drying the pellets to obtain the slag-iron separation accelerator.

9. The process for producing an accelerator for separating iron and slag according to claim 8, wherein: at least one of the following is satisfied:

the pressing pressure is 10-20 MPa;

the particle size of the pellets is 2-10 mm;

the drying temperature is 100-300 ℃;

the compression strength of the dried pellets is more than 800N.

10. The use method of the slag-iron separation accelerant is characterized in that: comprises a one-time adding method or a continuous adding method;

the one-time adding method comprises the following steps: in the titanium slag smelting process, when the power supply amount reaches 0.5 t-0.8 t MWh, adding the slag-iron separation accelerant into the furnace at one time according to 2-5% of the mass of the titanium concentrate; wherein t represents the feeding amount of the whole furnace, and the unit is ton;

a continuous addition process comprising the steps of: uniformly mixing the titanium concentrate, the slag-iron separation accelerant and the reducing agent according to the mass ratio of 100: 2-5: 10-20, and uniformly adding the mixture into the furnace at the speed of hour power supply/1.0-1.5; wherein the unit of the hourly power supply is MWh, and the unit of the speed is t/h.

Technical Field

The invention belongs to the technical field of titanium slag smelting, and particularly relates to a substance for accelerating slag-iron separation in a titanium slag smelting process, a preparation method and a use method thereof, which can effectively promote slag-iron separation and are suitable for various titanium slag smelting processes.

Background

In the titanium slag smelting process, titanium concentrate and a reducing agent react in an electric furnace to generate molten metal and molten slag, and slag-iron separation is realized under the action of gravity, so that titanium slag and molten iron are obtained. The slag-iron separation speed is too slow, which often causes iron inclusion in slag, higher smelting power consumption and increased molten iron temperature, thereby affecting the quality of titanium slag, the economic index of smelting and the safe operation of the electric furnace.

At present, titanium slag smelting enterprises at home and abroad improve the separation degree of slag and iron by controlling the superheat degree, the superheat time, the thickness of a slag iron layer and other methods in the production process to achieve the aim of reducing iron inclusion in slag, the methods are all physical separation methods adopted on the basis of maintaining the existing component conditions of slag and iron, and if the superheat degree and the superheat time are insufficient in the production process, the iron inclusion in the slag is easy to cause, and the slag tapping safety is threatened; if the degree of superheat and the time of superheat are higher, the temperature of an electric furnace system and the temperature of iron slag are increased easily, and further the safety of a furnace lining and related equipment is threatened; the thickness of the slag iron layer is difficult to measure and is difficult to accurately control.

Disclosure of Invention

The first problem to be solved by the invention is to provide a slag-iron separation promoter. The slag-iron separation accelerant is prepared from 70-90% of iron powder, 5-15% of coke powder, 2-8% of magnesium oxide powder, 1-5% of a binder and 1-5% of water by mass percent.

In the slag-iron separation accelerant, the content of metallic iron in the iron powder is more than 90%, and the content of C in the iron powder is 1-3%. Furthermore, the ratio of the particle size of the iron powder is less than or equal to 0.3mm and is more than 95 percent.

Further, in the above slag-iron separation accelerant, the iron powder is obtained by ball milling using by-products generated in the titanium slag crushing process, such as iron particles or iron wires, and other iron wastes as basic raw materials.

In the slag-iron separation accelerant, the content of C in the coke powder is more than 80%, the content of volatile matters is less than 5%, and the content of ash is less than 20%. The grain diameter of the coke powder is less than 1mm and is more than 90 percent.

Further, in the slag-iron separation accelerant, the coke powder is obtained by ball milling of fly ash or lump coke produced by coking.

Wherein, in the slag iron separation accelerant, the MgO content in the magnesia powder is more than 90 percent.

Wherein, in the slag iron separation accelerant, the binder is a solid organic binder.

The invention also provides a preparation method of the slag-iron separation accelerant. The preparation method comprises the following steps: and fully and uniformly mixing iron powder, coke powder, magnesium oxide powder, a binder and water to obtain a mixture, then pressing the mixture into pellets, and drying the pellets to obtain the slag-iron separation accelerator.

In the preparation method of the slag-iron separation accelerant, the pressing pressure is 10-20 MPa.

In the preparation method of the slag-iron separation accelerant, the particle size of the pellets is 2-10 mm.

In the preparation method of the slag iron separation accelerant, the drying temperature is 100-300 ℃.

In the preparation method of the slag-iron separation accelerant, the compression strength of the dried pellets is more than 800N.

The invention also provides a use method of the slag-iron separation accelerant. The using method comprises the following steps: in the titanium slag smelting process, when the power supply amount reaches 0.5 t-0.8 t MWh, adding the slag-iron separation accelerant into the furnace at one time according to 2-5% of the mass of the titanium concentrate; wherein t represents the feeding amount of the whole furnace and the unit is ton. The method is a one-time addition method.

The invention also provides a use method of the slag-iron separation accelerant. The using method comprises the following steps: uniformly mixing the titanium concentrate, the slag-iron separation accelerant and the reducing agent (coke or anthracite) according to the mass ratio of 100: 2-5: 10-20, and uniformly adding the mixture into the furnace at the speed of hour power supply/1.0-1.5; wherein the unit of the hourly power supply is MWh, and the unit of the speed is t/h. This process is known as a continuous addition process.

The slag-iron separation accelerant provided by the invention is added at one time or continuously in the titanium slag smelting process, so that the surface tension and interfacial tension conditions of slag iron can be improved, the slag-iron separation accelerant has the function of a nucleating agent, the growth of molten iron is accelerated, the separation conditions are improved, the slag-iron separation time is effectively shortened, the iron inclusion proportion in slag is reduced, the tapping temperature is reduced, the production power consumption is reduced, the product quality is improved, and the safe operation of an electric furnace is guaranteed.

Detailed Description

The preparation method of the slag iron separation accelerant comprises the following steps:

firstly, by-products generated in the process of crushing titanium slag, such as iron particles or iron wires and other iron wastes, are used as basic raw materials, and iron powder with the particle size of less than or equal to 0.3mm and the proportion of more than 95 percent is obtained after ball milling, wherein the content of metallic iron is more than 90 percent, and the content of C is 1-3 percent;

secondly, the fly ash or the lump coke produced by coking is ball-milled to obtain coke powder, the C content is more than 80 percent, the volatile component is less than 5 percent, the ash content is less than 20 percent, and the ratio of the particle size is less than 1mm and is more than 90 percent;

③ magnesia powder with MgO content more than 90 percent and solid organic binder;

mixing 70-90% of iron powder, 5-15% of coke powder, 2-8% of magnesium oxide powder, 1-5% of binder and 1-5% of water in percentage by mass, and fully stirring and mixing for 10-30 minutes by using a mixing and rolling machine to obtain a mixture A;

and fifthly, pressing the mixture A into pellets B by using a double-roller ball press, controlling the pressure of the ball press to be 10-20 MPa, controlling the particle size of the pellets B to be 2-10 mm, and drying the pellets B at 100-300 ℃ to obtain dried pellets C, wherein the compressive strength of the pellets is more than 800N, and the pellets C are the slag-iron separation accelerant. Standard ASTM E382-72.

The application method of the slag iron separation accelerant comprises a one-time adding method or a continuous adding method, and comprises the following steps:

one-time addition method: in the titanium slag smelting process, according to 2-5% of the mass of the titanium concentrate, the titanium concentrate is added into the furnace once when the power supply amount reaches the whole furnace charging amount (unit t) × (0.5-0.8) MWh in the later smelting period, and the uniform distribution of the pellets C in the smelting molten pool is ensured as far as possible.

② continuous addition method: the method comprises the steps of uniformly mixing the titanium concentrate, the pellet C and a reducing agent (coke or anthracite) according to the mass ratio of 100: 2-5: 10-20, and uniformly adding the mixture into a furnace through a quantitative feeder according to the speed of power supply quantity per hour (unit MWh)/(1.0-1.5) t/h. After the charging is finished, the slag can be discharged and the iron can be tapped without overheating.

In the present invention, the content, ratio, etc. are not particularly described, and all represent mass percentages.