A fluidized treatment method for electric furnace white slag and semi-magnetic roller thereof

Abstract

The present invention relates to a fluidized treatment method for electric furnace white slag and a semi-magnetic drum thereof, and belongs to the technical field of steel slag treatment. Technical scheme: the crushed white slag is adsorbed by an electromagnetic magnetic disk to a ferrite material with a diameter of 200-500mm and an iron content of more than 80%, and is recycled for steelmaking; the white slag with less magnetism left after magnetic separation is screened, and the 10-200mm screen material is disposed together with the black steel slag produced in the converter or electric furnace steelmaking process, and the powdered white slag with a particle size of less than 10mm is subjected to secondary magnetic separation; the ferrite material with an iron content of more than 50% in the secondary magnetic separation is recycled for steelmaking; the screen material with a particle size of ≤5mm after the secondary magnetic separation can be used as a cement-grade ingredient for downstream enterprises, and the screen material with a particle size of >5mm is disposed together with the black steel slag produced in the converter or electric furnace steelmaking process. The beneficial effects of the present invention: the ferrite raw materials in the white slag can be recovered, the activity of the white slag can be improved, the physical properties can be improved, and cement-grade ingredients can be provided for downstream enterprises.

Description

Technical Field

[0001] The invention relates to a fluidized treatment method for electric furnace white slag and a semi-magnetic roller thereof, belonging to the technical field of treatment of electric furnace steelmaking slag in the metallurgical industry. Background Art

[0002] The industrial transformation and upgrading and green development of the steel industry have put forward higher requirements for the comprehensive utilization of resources. For short-process steel enterprises, the emission of atmospheric pollutants per ton of steel in the smelting process is small, which is its inherent environmental advantage. However, in terms of the comprehensive utilization of steel slag, there are still mixed processes, low utilization rates, and no outstanding energy-saving and environmental protection advantages. This requires and promotes steel enterprises to continuously seek breakthroughs in the comprehensive utilization of steel slag resources in new processes, new technologies, and new equipment, and expand the comprehensive utilization of steel slag resources to deeper and wider application fields, so as to achieve the goal of "reducing, recycling, and harmless" steel slag resources.

[0003] Steel slag is mainly waste slag produced during the steelmaking process of converters or electric furnaces. It is usually black. Its treatment processes include hot pouring, hot stuffing, drum method, air quenching and water quenching, which have been widely adopted.

[0004] White slag is an industrial waste slag produced by the short-process electric arc furnace refining process. It is white in color and is a sub-category of steel slag. Its amount is generally 1.0-1.2% of the crude steel output. It has the characteristics of easy dispersion and pulverization. White slag is generally abandoned as waste, which not only occupies a large amount of land resources, but also pollutes the environment. Therefore, the resource utilization of white slag is of great significance both to the enterprise itself and to society.

[0005] Moreover, white slag is only produced in the refining process of electric arc furnace, so there is currently a lack of successful examples of resource utilization of white slag. Summary of the invention

[0006] The purpose of the present invention is to provide a fluidized treatment method for electric furnace white slag and a semi-magnetic roller thereof, which can not only recover the ferrous raw materials in the white slag, but also improve the activity of the white slag, improve the physical properties, provide cement-grade ingredients for downstream enterprises, and solve the problems existing in the background technology.

[0007] The technical solution of the present invention is:

[0008] A method for fluidizing white slag of an electric furnace is carried out according to the following steps:

[0009] ① Cool the high-temperature white slag at 950-1150℃ naturally to below 550℃;

[0010] ② Crush the above white slag to a particle size of less than 500mm;

[0011] ③ The crushed white slag is adsorbed by an electromagnetic disk to obtain ferrous materials with a particle size of 200-500mm and an iron content of more than 80%, which are recycled for steelmaking;

[0012] ④ The white slag with little magnetism left after magnetic separation is screened, and the oversize with a particle size of 10-200mm is disposed together with the black steel slag produced in the converter or electric furnace steelmaking process, and the powdery white slag with a particle size of less than 10mm is subjected to secondary magnetic separation;

[0013] ⑤ The ferrous material with an iron content of ≥50% in the secondary magnetic separation is recycled for steelmaking;

[0014] ⑥ The active materials after the secondary magnetic separation are screened. The undersize materials with a particle size of ≤5mm can be used as cement-grade ingredients for downstream enterprises, and the oversize materials with a particle size of >5mm can be disposed together with the black slag produced during the converter or electric furnace steelmaking process.

[0015] The secondary magnetic separation uses a semi-magnetic drum for magnetic separation.

[0016] A semi-magnetic roller comprises a pull rod, an adjusting arm, a connecting plate, a permanent magnetic arc plate, a roller drive shaft, a roller body, a roller side plate, an adjusting shaft, a shaft head and a bushing. Roller side plates are respectively arranged on both sides of the roller body. An adjusting shaft bearing matching the adjusting shaft is arranged on the roller side plates. The roller side plate on one side of the roller body is connected to the roller drive shaft through roller bearing one. The adjusting shaft on the other side of the roller body is arranged on roller bearing two. The roller drive shaft and the adjusting shaft are arranged concentrically. The roller bearing one is arranged concentrically with the adjusting shaft bearing. The permanent magnetic arc plate is arranged inside the roller body and is an arc-shaped plate matching the curvature of the roller body. Both ends of the permanent magnetic arc plate are respectively fixed on the adjusting shaft through connecting plates. A bushing is arranged on the shaft head of the adjusting shaft on one side of roller bearing two, and the bushing is connected to the pull rod through the adjusting arm.

[0017] The permanent magnetic arc plate and the connecting plates at both ends of the permanent magnetic arc plate form a fan shape.

[0018] The sector angle formed by the permanent magnetic arc plate and the connecting plates at both ends of the permanent magnetic arc plate is 120-160°.

[0019] The gap between the permanent magnetic arc plate and the drum body is 20-40 mm.

[0020] The adjusting arm is connected to the pull rod via bolts.

[0021] The beneficial effects of the present invention are: comprehensive utilization of white slag resources is a very practical and necessary environmental protection project. It can not only recover the iron raw materials in the white slag, but also improve the activity of the white slag, improve the physical properties, provide cement-grade ingredients for downstream enterprises, save energy and electricity, and reduce pollutant emissions. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1This is the front view of the half magnetic drum;

[0023] Figure 2 It is the side view of the half magnetic drum;

[0024] In the figure: retaining ring 1, pull rod 2, adjusting arm 3, drum belt 4, drum bearing 1 5, connecting plate 6, permanent magnetic arc plate 7, drum transmission shaft 8, adjusting shaft bearing 9, drum body 10, drum side plate 11, adjusting shaft 12, shaft head 13, shaft sleeve 14, drum bearing 2 15. DETAILED DESCRIPTION

[0025] The present invention will be further described below by way of examples with reference to the accompanying drawings.

[0026] See attached Figure 1-2 , a method for fluidizing white slag of an electric furnace, which is operated according to the following steps:

[0027] ① Cool the high-temperature white slag at 950-1150℃ naturally to below 550℃;

[0028] ② Crush the above white slag to a particle size of less than 500mm;

[0029] ③ The crushed white slag is adsorbed by an electromagnetic disk to obtain ferrous materials with a particle size of 200-500mm and an iron content of more than 80%, which are recycled for steelmaking;

[0030] ④ The white slag with little magnetism left after magnetic separation is screened, and the oversize with a particle size of 10-200mm is disposed together with the black steel slag produced in the converter or electric furnace steelmaking process, and the powdery white slag with a particle size of less than 10mm is subjected to secondary magnetic separation;

[0031] ⑤ The ferrous material with an iron content of ≥50% in the secondary magnetic separation is recycled for steelmaking;

[0032] ⑥ The active materials after the secondary magnetic separation are screened. The undersize materials with a particle size of ≤5mm can be used as cement-grade ingredients for downstream enterprises, and the oversize materials with a particle size of >5mm can be disposed together with the black slag produced during the converter or electric furnace steelmaking process.

[0033] A semi-magnetic roller comprises a pull rod 2, an adjusting arm 3, a connecting plate 6, a permanent magnetic arc plate 7, a roller drive shaft 8, a roller body 10, a roller side plate 11, an adjusting shaft 12, a shaft head 13 and a sleeve 14. The roller side plates 11 are respectively arranged on both sides of the roller body 10, and the roller side plates 11 are provided with adjusting shaft bearings 9 matching the adjusting shaft 12. The roller side plate on one side of the roller body 10 is connected to the roller drive shaft 8 through a roller bearing 1 5, and the adjusting shaft 12 on the other side of the roller body 10 is arranged on a roller bearing 2 15. The roller drive shaft 8 and the adjusting shaft 12 are arranged concentrically, and the roller bearing 1 5 and the adjusting shaft bearing 9 are arranged concentrically; the permanent magnetic arc plate 7 is arranged inside the roller body 10, and is an arc-shaped plate matching the curvature of the roller body 10. The two ends of the permanent magnetic arc plate 7 are respectively fixed on the adjusting shaft 12 through connecting plates 6, and a sleeve 14 is provided on the shaft head 13 of the adjusting shaft 12 on one side of the roller bearing 2 15, and the sleeve 14 is connected to the pull rod 2 through the adjusting arm 3.

[0034] In this example, refer to the attached Figure 1 , 2 The specific installation process of the semi-magnetic roller is as follows:

[0035] The pull rod 2 is connected to the adjusting arm 3 through bolts, and the adjusting arm 3 is connected to the shaft head 13 through the shaft sleeve 14 to achieve the purpose of rotating the adjusting shaft 12. The adjusting shaft 12 is rotatably connected to the drum side plate 11 through the adjusting shaft bearing 9.

[0036] The two ends of the permanent magnetic arc plate 7 are fixed on the adjustment shaft 12 through the connecting plates 6 respectively, and the permanent magnetic arc plate 7 and the connecting plates 6 form a sector with an angle of 150 degrees inside the drum.

[0037] Magnetic system angle adjustment: First, pull the pull rod 2 to drive the adjusting arm 3 to the appropriate position. The adjusting arm 3 can rotate the adjusting shaft 12 through the shaft sleeve 14 and the shaft head 13, so as to adjust the relative angle between the permanent magnetic arc plate 7 and the drum body 10. The gap between the permanent magnetic arc plate 7 and the drum body 10 is 30mm. Finally, the pull rod 2 is fixed by the clamping ring 1.

[0038] Magnetic separation: The permanent magnetic arc plate 7 forms a magnetic field in the direction facing the drum body 10. Because the gap between the permanent magnetic arc plate 7 and the drum body 10 is equal, the magnetic force of the magnetic field is uniform, and the iron-containing materials can be adsorbed. When the mixed material approaches the magnetic surface of the semi-magnetic drum along with the drum belt 4, it gradually enters the magnetic field area formed by the permanent magnetic arc plate 7. The non-magnetic material rolls in front of the semi-magnetic drum in advance due to the inertia of the drum belt; the iron-containing material is adsorbed on the drum belt. As the drum belt runs, the magnetic force disappears and it falls off the drum belt due to the superposition of natural gravity and centrifugal force, completing the magnetic separation of iron-containing materials and non-magnetic materials.

[0039] The fluidization treatment method of electric furnace white slag is specifically carried out according to the following steps:

[0040] ①Raw material preparation

[0041] The raw material is high-temperature white slag produced in the electric furnace refining section: the temperature is 950~1150℃;

[0042] ②Standing and breaking

[0043] The high-temperature white slag is left in the white slag treatment workshop for 24-48 hours until the temperature drops below 550℃, and then it is concentrated in the crushing pool and crushed by the pestle head of the hook machine. After crushing, the particle size is less than 500mm;

[0044] ③Magnetic separation, fluidization

[0045] The crushed white slag passes through the electromagnetic disk of the overhead crane. Its high-temperature electromagnet is MW5-165L / G, with a temperature of ≤500℃, a voltage of 220V, and a power of 13.3kW. It mainly absorbs the white slag with an equivalent particle size of 200-500mm and an iron content of more than 80%, and absorbs the ferrous raw materials in the white slag. The magnetically selected ferrous raw materials are transported to the steelmaking process for reuse;

[0046] The white slag with little magnetism left after magnetic separation is transported to a fluidized flat car. The fluidized flat car has a two-layer structure, the upper layer is a grid-mounted pressure plate, the lower layer is a dense mesh screen, and the bottom of the fluidized flat car is a conical bucket. The hydraulic system is used to push the fluidized flat car to flow in different stations in sequence. During the flow, the vibrating device of the fluidized flat car is used to make the powdered white slag with a particle size of less than 10mm enter the conical bucket of the fluidized flat car, and the screened material with a particle size of 10-200mm is transported to the steelmaking process and disposed together with the black steel slag produced in the electric arc furnace steelmaking process;

[0047] ④Secondary magnetic separation and screening

[0048] The powdered white slag in the conical bucket of the fluidized flat car is subjected to secondary magnetic separation by a semi-magnetic drum with a drum diameter of φ800mm, a surface magnetic field strength of 3600-4000Gs, and a magnetic system angle of 175°. The active white slag with an iron content of ≥50% is recycled for steelmaking. The white slag with an iron content of less than 50% is screened, and the finished materials with a very low iron content and a particle size of ≤5mm can be used as cement-grade ingredients for downstream enterprises. The materials on the screen with a particle size of >5mm are transported to the steelmaking process and disposed of together with the black slag produced in the electric arc furnace steelmaking process.

Claims

1. A method for fluidizing white slag from an electric furnace, characterized in that: Follow these steps: ① Cool the high-temperature white slag at 950-1150℃ naturally to below 550℃; ② Crush the above white slag to a particle size of less than 500mm; ③ The crushed white slag is adsorbed by an electromagnetic disk to obtain ferrous materials with a particle size of 200-500mm and an iron content of more than 80%, which are recycled for steelmaking; ④ Screening the white slag with little magnetism left after magnetic separation, and transporting the white slag with little magnetism left after magnetic separation to a fluidized flat car. The fluidized flat car has a two-layer structure, the upper layer is a grid-mounted pressure plate, the lower layer is a dense mesh screen, and the bottom of the fluidized flat car is a conical bucket. The hydraulic system is used to push the fluidized flat car to flow in different stations in sequence. During the flow, the vibrating device of the fluidized flat car is used to make the powdered white slag with a particle size of less than 10mm enter the conical bucket of the fluidized flat car, and the screened material with a particle size of 10-200mm is transported to the steelmaking process and disposed together with the black steel slag produced in the electric arc furnace steelmaking process. The powdered white slag with a particle size of less than 10mm undergoes secondary magnetic separation; ⑤ The ferrous material with an iron content of ≥50% in the secondary magnetic separation is recycled for steelmaking; ⑥ The active materials after the secondary magnetic separation are screened, and the undersize materials with a particle size of ≤5mm are used as cement-grade ingredients for downstream enterprises, and the oversize materials with a particle size of >5mm are disposed together with the black steel slag produced during the converter or electric furnace steelmaking process; The secondary magnetic separation adopts a semi-magnetic drum for magnetic separation, and the semi-magnetic drum comprises a pull rod (2), an adjustment arm (3), a connecting plate (6), a permanent magnetic arc plate (7), a drum transmission shaft (8), a drum body (10), a drum side plate (11), an adjustment shaft (12), a shaft head (13) and a shaft sleeve (14). Drum side plates (11) are respectively arranged on both sides of the drum body (10), and an adjustment shaft bearing (9) matching the adjustment shaft (12) is arranged on the drum side plate (11). The drum side plate on one side of the drum body (10) is connected to the drum transmission shaft (8) through a drum bearing 1 (5). The drum body (10) is also provided with a drum bearing 2 (6). The adjusting shaft (12) on one side is arranged on the second roller bearing (15), the roller drive shaft (8) and the adjusting shaft (12) are arranged concentrically, and the first roller bearing (5) and the adjusting shaft bearing (9) are arranged concentrically; the permanent magnetic arc plate (7) is arranged inside the roller body (10) and is an arc-shaped plate that matches the curvature of the roller body (10), and the two ends of the permanent magnetic arc plate (7) are respectively fixed to the adjusting shaft (12) through connecting plates (6), and a shaft sleeve (14) is provided on the shaft head (13) of the adjusting shaft (12) on one side of the second roller bearing (15), and the shaft sleeve (14) is connected to the pull rod (2) through the adjusting arm (3).

2. The method for fluidizing white slag from an electric furnace according to claim 1, characterized in that: The permanent magnetic arc plate (7) and the connecting plates (6) at both ends of the permanent magnetic arc plate (7) form a sector shape.

3. The method for fluidizing white slag from an electric furnace according to claim 2, characterized in that: The sector angle formed by the permanent magnetic arc plate (7) and the connecting plates (6) at both ends of the permanent magnetic arc plate (7) is 120-160°.

4. The method for fluidizing white slag from an electric furnace according to claim 1, characterized in that: The gap between the permanent magnetic arc plate (7) and the drum body (10) is 20-40 mm.

5. The method for fluidizing white slag from an electric furnace according to claim 1, characterized in that: The adjusting arm (3) is connected to the pull rod (2) via bolts.

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