Steel slag treatment equipment

Abstract

The utility model relates to steel slag treatment equipment. The steel slag treatment equipment comprises a reduction steel ladle, a rotary injection device and a heating device, the reduction steel ladle is used for placing molten steel slag; the rotary injection device is used for rotationally injecting a reducing agent into the molten steel slag in the reduction steel ladle to carry out reduction reaction; and the heating device is used for heating the reduction steel ladle. According to the steel slag treatment equipment, molten steel separation is thorough, the steel recovery rate is increased, steel slag sensible heat is fully utilized, energy consumption is low, the steel slag dynamic condition is good, and safety and stability are good.

Description

Technical Field

[0001] This application relates to the field of metallurgical technology, and in particular to a steel slag treatment device. Background Technology

[0002] Steel slag mainly includes converter slag, refining slag, foundry residue slag, ladle slag, desulfurization slag, dephosphorization slag, and desiliconization slag, among which converter slag accounts for more than 80% of the total steel slag. Converter slag contains a large number of beneficial elements such as CaO, FeO, MnO, and MgO, which can be recycled, but it also contains harmful elements such as Cr2O3 and P2O5. Some CaO and MgO exist in a free state and expand in volume when exposed to water. Depending on the characteristics of the steel slag, steel slag treatment technologies mainly include hot blanching, hot pouring, drum quenching, air quenching, and water quenching. However, in traditional steel slag treatment technologies, apart from magnetic separation of metallic iron for iron recovery and steelmaking, steel tailings are difficult to utilize directly or have low utilization rates, resulting in resource waste. Utility Model Content

[0003] Therefore, it is necessary to provide steel slag treatment equipment that can promote steel separation and improve steel recovery rate.

[0004] One aspect of this application provides a steel slag treatment device, including a reducing ladle, a rotary jetting device, and a heating device;

[0005] The reduction ladle is used to hold molten steel slag;

[0006] The rotary jetting device is used to rotary jet a reducing agent onto the molten steel slag in the reducing ladle for a reduction reaction;

[0007] The heating device is used to heat the reduced steel ladle.

[0008] The aforementioned steel slag treatment equipment, through a reducing ladle containing molten steel slag and a rotary jetting device, mixes high-temperature molten steel slag and reducing agent in the reducing ladle. The reducing agent can be added to the molten steel slag via rotary jetting, which not only maximizes the utilization of the physical heat of the molten steel slag, but also effectively reduces a large amount of FeO after the molten steel slag is treated by the rotary jetting device, thereby improving the steel recovery rate and promoting the complete separation of molten steel. In addition, heating the mixture of molten steel and reducing slag through a heating device not only improves the fluidity of the mixture, but also allows time for the reduced molten steel to fall back, further promoting the complete separation of molten steel and reducing slag, and further improving the steel recovery rate. Simply introducing a rotary jetting device into the molten steel slag in the reduction ladle can easily lead to a decrease in the fluidity of the molten steel slag. However, the aforementioned equipment utilizes the hot molten steel slag in the reduction ladle to carry out a full reduction reaction with the reducing agent sprayed by the rotary jetting device. At the same time, it utilizes the heat of the molten steel slag itself and combines it with a heating device for heating treatment, which synergistically enhances the fluidity of the molten steel slag and promotes steel-slag separation.

[0009] The aforementioned steel slag treatment equipment reduces the P2O5 content in molten steel slag, which not only reduces the amount of phosphorus entering the molten steel, but also facilitates the subsequent utilization of the reducing slag and reduces environmental pollution.

[0010] The aforementioned steel slag processing equipment makes full use of the sensible heat of steel slag, resulting in low energy consumption, good slag dynamics, and good safety and stability.

[0011] In some embodiments, the steel slag treatment equipment further includes a sealing plug and a sealing plug fixing plate. The reducing steel ladle is provided with a steel outlet. The sealing plug is used to seal the steel outlet. The sealing plug fixing plate is used to be located outside the sealing plug and to fix the sealing plug when the sealing plug seals the steel outlet. The sealing plug fixing plate can be slidably connected to the reducing steel ladle to be close to or away from the steel outlet.

[0012] In some embodiments, the steel slag processing equipment further includes a receiving ladle and a slag pot; the reducing ladle has a connection port and a steel outlet at its bottom; the connection port can be selectively connected to the rotary jetting device or the heating device, and the steel outlet can be selectively connected to the receiving ladle or the slag pot.

[0013] In some embodiments, the slag treatment equipment further includes a reversing device located below the reducing ladle, and the outlet can be selectively connected to the receiving ladle or the slag pot via the reversing device.

[0014] In some embodiments, the commutator includes an interconnected molten steel guide section and a slag guide section, and the commutator is movable relative to the reducing ladle so that the molten steel guide section or the slag guide section is selectively configured to correspond to the outlet.

[0015] In some embodiments, both the molten steel guide section and the slag guide section are guide surfaces, and the molten steel guide section and the slag guide section are connected to form an angle. The molten steel guide section is inclined from top to bottom toward the receiving ladle, and the slag guide section is inclined from top to bottom toward the slag pot.

[0016] In some embodiments, the molten steel guide section and the slag guide section form an angle of 60 degrees to 120 degrees.

[0017] In some embodiments, the rotary jetting device is a rotary spray gun.

[0018] In some embodiments, the steel slag treatment equipment further includes an air quenching device with the air outlet facing the slag discharge end of the commutator.

[0019] In some embodiments, the steel slag treatment equipment further includes a slag collection device, which includes a slag collection chamber with a steel slag inlet, a steel slag outlet and a dust discharge port, and the steel slag outlet is connected to a slag pot. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the steel slag treatment equipment in one embodiment.

[0021] Figure 2 for Figure 1 A schematic diagram of the working status of the steel slag treatment equipment.

[0022] Figure 3 This is a schematic diagram of the commutator in one embodiment.

[0023] Explanation of reference numerals in the attached figures:

[0024] 1. Reduction ladle; 11. Connection port; 12. Steel outlet; 2. Heating device; 3. Ladle receiving device; 4. Slag pot; 5. Sealing plug; 6. Sealing plug fixing plate; 7. Reversing device; 71. Molten steel guide plate; 72. Slag guide plate; 73. Watershed; 8. Air outlet; 9. Slag collection device; 91. Slag collection chamber; 92. Slag inlet; 93. Slag outlet; 94. Dust discharge port; 95. Bucket hopper; 96. Valve; 10. Platform; 100. Support; 101. Molten steel; 102. Reduction slag. Detailed Implementation

[0025] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings. Preferred embodiments of this application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of this application.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0027] Currently, steel tailings are either difficult to utilize directly or have a low steel recovery rate. Traditional technologies include crushing the steel tailings, screening them, and then magnetically separating the iron for utilization. This method is not only complex, sometimes involving more than a dozen steps, but also has a low recovery rate. Other methods attempt to use reducing agents to reduce FeO before recovery, but this often fails to achieve a complete reaction, resulting in low steel recovery and high energy consumption, making it unprofitable.

[0028] Based on this, one embodiment of this application provides a steel slag treatment method, including the following steps:

[0029] The reducing agent is added to the molten steel slag by rotary jetting to carry out the reduction reaction, resulting in a mixture of molten steel and reducing slag.

[0030] After heating the mixture, the reducing slag and the molten steel are separated from the mixture.

[0031] Understandably, the reduced molten steel, being denser than the reducing slag, accumulates in the lower layer, while the reducing slag remains in the upper layer.

[0032] The aforementioned steel slag treatment method mixes high-temperature molten steel slag with a reducing agent, which is then added to the molten steel slag via rotary jetting. This not only maximizes the utilization of the physical heat of the molten steel slag but also effectively reduces a large amount of FeO after rotary jetting, thereby improving steel recovery and promoting thorough steel-slag separation. Furthermore, heating the mixture of molten steel and reducing slag not only enhances the fluidity of the mixture but also allows time for the reduced molten steel to recede, further promoting complete separation of the steel and reducing slag and further improving steel recovery. Simply introducing rotary jetting into the molten steel slag can easily lead to decreased fluidity. However, the aforementioned steel slag treatment method utilizes the hot molten steel slag and reducing agent to undergo a thorough reduction reaction under rotary jetting, while simultaneously utilizing the molten steel slag's own heat in conjunction with the heating treatment, synergistically enhancing the fluidity of the molten steel slag and promoting steel-slag separation.

[0033] The above-mentioned steel slag treatment method reduces the mass content of P2O5 in molten steel slag, which not only reduces the amount of phosphorus entering the molten steel, but also facilitates the subsequent utilization of the reducing slag and reduces environmental pollution.

[0034] The above-mentioned steel slag treatment method makes full use of the sensible heat of steel slag, resulting in low energy consumption, good slag kinetic conditions, and good safety and stability.

[0035] In some embodiments, the rotary jetting time is 6 to 10 minutes. This jetting time not only facilitates the uniform dissolution of the reducing agent in the molten steel slag, avoiding localized excessively high or low concentrations and improving steel recovery, but also ensures sufficient reaction within this time range while preventing the steel slag from corroding the refractory material in the ladle; furthermore, it also improves the fluidity of the mixture.

[0036] As an example, the blowing time of the rotary jet can be 6 min, 7 min, 8 min, 9 min and 10 min, or any of the aforementioned values ​​as the end values.

[0037] In some embodiments, the rotary jet blowing time is 6 to 8 minutes. This further improves the fluidity of the mixture and the steel recovery rate.

[0038] In some embodiments, the rotational speed of the rotary jet is 80 rpm to 130 rpm.

[0039] As an example, the rotational speed of the rotary jet can be 80 rpm, 85 rpm, 90 rpm, 95 rpm, 100 rpm, 105 rpm, 110 rpm, 115 rpm, 120 rpm, 125 rpm, and 130 rpm, or within a range consisting of any two of the aforementioned values ​​as endpoints.

[0040] In some embodiments, the rotary jetting speed is 30 kg / (min·ton slag) to 50 kg / (min·ton slag).

[0041] As an example, the spraying speed of the rotary jet can be 30 kg / (min·ton slag), 31 kg / (min·ton slag), 32 kg / (min·ton slag), 33 kg / (min·ton slag), 34 kg / (min·ton slag), 35 kg / (min·ton slag), 36 kg / (min·ton slag), 37 kg / (min·ton slag), 38 kg / (min·ton slag), 39 kg / (min·ton slag), 40 kg / (min·ton slag), 41 kg / (min·ton slag), 42 kg / (min·ton slag), 43 kg / (min·ton slag), 44 kg / (min·ton slag), 45 kg / (min·ton slag), 46 kg / (min·ton slag), 47 kg / (min·ton slag), 48 kg / (min·ton slag), 49 kg / (min·ton slag), 50 kg / (min·ton slag), or within the range formed by any two of the aforementioned values ​​as endpoints.

[0042] In some embodiments, the rotational speed of the rotary jet is 80-90 rpm when the jetting time is 0-5 minutes, and 120-130 rpm when the jetting time is >5 minutes. The gradual increase in rotational speed ensures uniform distribution of the reducing agent, avoiding uneven distribution caused by excessive centrifugal force. Furthermore, this rotational speed prevents excessive breakage of the reducing agent, which could lead to vortices and complex, uncontrollable flow paths, affecting the reaction efficiency and thus improving the steel recovery rate.

[0043] Furthermore, the rotation speed of the rotary jet when the blowing time is 0 to 5 minutes is preferably 80 to 85 rpm.

[0044] Furthermore, the rotational speed for >5 minutes is preferably 120 rpm to 125 rpm.

[0045] In some embodiments, the rotary jet blowing speed is 30-40 kg / (min·ton slag) when the blowing time is 0-5 min, and 41-50 kg / (min·ton slag) when the blowing time is >5 min. Increasing the blowing speed gradually avoids the accumulation of reducing agent in localized areas, improves the uniformity of reducing agent distribution, and thus increases the steel recovery rate.

[0046] Furthermore, the preferred blowing speed for the rotary jet when the blowing time is 0-5 min is 30-35 kg / min·ton of slag.

[0047] Furthermore, the preferred blowing speed for >5 min is 41 to 45 (kg / min·tons of slag).

[0048] In some embodiments, the rotational speed of the rotary jet is 80-90 rpm during the 0-5 min period and 120-130 rpm during the >5 min period; the jetting velocity is 30-40 kg / (min·ton slag) during the 0-5 min period and 41-50 kg / (min·ton slag) during the >5 min period. This further promotes the complete separation of molten steel and reducing slag, and improves the steel recovery rate.

[0049] In some embodiments, the molten steel slag is the liquid steel slag after tapping from the converter.

[0050] In some embodiments, the temperature of the molten steel slag is 1560°C to 1650°C.

[0051] Furthermore, the molten steel slag is the liquid steel slag produced after tapping from the converter.

[0052] In some embodiments, the reducing agent is a carbon or silicon-based material.

[0053] Furthermore, the reducing agent is carbon powder or ferrosilicon powder.

[0054] Furthermore, the reducing agent is carbonaceous dust such as pulverized coal, coke powder, and blast furnace ash, or ferrosilicon powder.

[0055] In some embodiments, the mass ratio of the reducing agent to the molten steel slag is 1 / 25 to 1 / 20.

[0056] In some embodiments, the temperature of the heat treatment is ≥1420°C.

[0057] In some embodiments, the temperature of the heat treatment is 1420°C to 1500°C.

[0058] As an example, the temperature of the heat treatment can be 1420℃, 1425℃, 1430℃, 1435℃, 1440℃, 1445℃, 1450℃, 1455℃, 1460℃, 1465℃, 1470℃, 1475℃, 1480℃, 1485℃, 1490℃, 1495℃, and 1500℃, or a range formed by any two of the aforementioned values ​​as endpoints. The preferred temperature for the heat treatment is 1450℃ to 1500℃.

[0059] In some embodiments, the heat treatment holding time is 20 min to 30 min.

[0060] As an example, the holding time for the heat treatment is 20 min, 21 min, 22 min, 23 min, 24 min, 25 min, 26 min, 27 min, 28 min, 29 min, and 30 min, or within the range formed by any two of the aforementioned values ​​as endpoints. Preferably, it is 20 min to 25 min.

[0061] In some embodiments, the molten steel slag after rotary blowing is heated and kept warm by introducing gas.

[0062] Furthermore, the calorific value of the gas is 5000 J / Nm³. 3 ~12000J / Nm 3 The flow rate is 200 Nm 3 / h~1000Nm 3 / h, pressure is 1000Pa~5000Pa.

[0063] In some embodiments, a steel slag air quenching step is also included, which comprises the following steps: after separating the molten steel deposited at the bottom layer, the reducing slag is subjected to air quenching at a pressure of 0.3 MPa to 0.6 MPa and an air volume of 40,000 Nm³. 3 / h~100000Nm 3 High-pressure air is injected and collected at a rate of / h. Utilizing air quenching to collect steel slag particles enables rapid transfer of high-temperature steel slag, achieving continuous production and significantly improving production efficiency.

[0064] For the second aspect of this application, please refer to Figure 1 A steel slag treatment device is provided.

[0065] It includes a reduction ladle 1, a rotary jetting device (not shown), and a heating device 2;

[0066] Ladle 1 is used to hold molten steel slag;

[0067] The rotary jetting device is used to rotary jet the reducing agent into the molten steel slag in the reducing ladle 1 for reduction reaction;

[0068] Heating device 2 is used to heat the reduction ladle.

[0069] The aforementioned steel slag treatment equipment, through a reducing ladle containing molten steel slag and a rotary jetting device, mixes high-temperature molten steel slag and reducing agent in the reducing ladle. The reducing agent can be added to the molten steel slag via rotary jetting, which not only maximizes the utilization of the physical heat of the molten steel slag, but also effectively reduces a large amount of FeO after the molten steel slag is treated by the rotary jetting device, thereby improving the steel recovery rate and promoting the complete separation of molten steel. In addition, heating the mixture of molten steel and reducing slag through a heating device not only improves the fluidity of the mixture, but also allows time for the reduced molten steel to fall back, further promoting the complete separation of molten steel and reducing slag, and further improving the steel recovery rate. Simply introducing a rotary jetting device into the molten steel slag in the reduction ladle can easily lead to a decrease in the fluidity of the molten steel slag. However, the aforementioned equipment utilizes the hot molten steel slag in the reduction ladle to carry out a full reduction reaction with the reducing agent sprayed by the rotary jetting device. At the same time, it utilizes the heat of the molten steel slag itself and combines it with a heating device for heating treatment, which synergistically enhances the fluidity of the molten steel slag and promotes steel-slag separation.

[0070] The aforementioned steel slag treatment equipment reduces the P2O5 content in molten steel slag, which not only reduces the amount of phosphorus entering the molten steel, but also facilitates the subsequent utilization of the reducing slag and reduces environmental pollution.

[0071] The aforementioned steel slag processing equipment makes full use of the sensible heat of steel slag, resulting in low energy consumption, good slag dynamics, and good safety and stability.

[0072] In some embodiments, the heating device 2 is a baker. The baker may be a sliding baker, a flip-top baker, or a rotary baker.

[0073] In some embodiments, the steel slag treatment equipment further includes a receiving ladle 3 and a slag pot 4; the reducing ladle 1 has a connection port 11, and the bottom of the reducing ladle 1 has a steel outlet 12. The connection port 11 can be selectively connected to the rotary jetting device or the heating device 2, and the steel outlet 12 can be selectively connected to the receiving ladle 3 or the slag pot 4.

[0074] Understandably, the rotary jetting device and heating device 2 are adapted to the connection port 11 of the reduction ladle 1; during the reduction reaction, the rotary jetting device is connected to the connection port 11; during the heat treatment, the rotary jetting device is removed from the connection port 11, and then the heating device 2 is connected to the connection port 11. The rotary jetting device can be an existing rotary spray gun.

[0075] In some embodiments, a rotary spray gun is mounted on platform 10; the rotary spray gun is rotatable about its axis; the discharge end of the rotary spray gun is located inside the reducing ladle 1; the rotary spray gun includes a powder spraying pipe, a support pipe, and a heat insulation pipe nested from the inside out; the discharge end of the powder spraying tank is connected to the inlet end of the powder spraying pipe via a connecting pipe for spraying reducing agent powder into the reducing ladle 1; a rotation control device is mounted on platform 10 and connected to the support pipe to control the rotation of the rotary spray gun; the rotary spray gun also includes a paddle, which, in use, directs the rotary spray gun from the connection port 1 of the reducing ladle 1. The rotary nozzle is inserted into the molten steel slag at one point, so that the molten steel slag submerges the blades of the rotary nozzle. In the rotary nozzle, the outermost heat insulation pipe is used to insulate and protect the inner powder spraying pipe and support pipe. The support pipe is connected to the rotation control device to control the rotation of the rotary nozzle around its axis. The reducing agent powder is sprayed through the powder spraying pipe and sprayed into the molten steel slag through the discharge end of the powder spraying pipe of the rotary nozzle. At the same time, the rotation of the rotary nozzle causes the blades to stir the molten steel slag, which can mix the reducing agent powder and the molten steel slag, so that the molten steel slag can generate molten steel under the action of reduction reaction.

[0076] In some embodiments, the slag treatment equipment further includes a sealing plug 5 and a sealing plug fixing plate 6. The sealing plug 5 is used to seal the steel outlet 12, and the sealing plug fixing plate 6 is positioned outside the sealing plug 5 and fixes it when the sealing plug 5 seals the steel outlet 12. The sealing plug fixing plate 6 can be slidably connected to the reducing ladle 1 to be close to or away from the steel outlet 12. By using the sealing plug 5 and the sealing plug fixing plate 6 to seal the steel outlet 12, it is ensured that the steel outlet 12 of the reducing ladle 1 can still be opened even when the static pressure of the slag is low.

[0077] In some embodiments, the slag treatment equipment further includes a reversing device 7 located below the reducing ladle 1. The slag outlet 12 can be selectively connected to the receiving ladle 3 or the slag pot 4 via the reversing device 7. Switching between molten steel and reducing slag discharge is achieved by moving the position of the reversing device 7. When molten steel is discharged first and reducing slag is discharged later, it is not necessary to close the sealing plug fixing plate 6 in between; simply sliding the sealing plug fixing plate 6 open once is sufficient to completely discharge both molten steel and reducing slag from the reducing ladle 1.

[0078] In some embodiments, the commutator includes interconnected molten steel guide sections and slag guide sections, and the commutator is movable relative to the reducing ladle to selectively align the molten steel guide section or the slag guide section with the outlet. This commutator promotes complete separation of molten steel and reducing slag, has a simple and flexible structure, achieves continuity in the steel-slag separation process, and significantly improves slag processing efficiency.

[0079] In some embodiments, both the molten steel guide section and the slag guide section are guide surfaces, and the molten steel guide section and the slag guide section are connected to form an angle. The molten steel guide section is inclined from top to bottom toward the ladle receiving the steel, and the slag guide section is inclined from top to bottom toward the slag pot.

[0080] In some embodiments, the molten steel guide section and the slag guide section form an angle of 60 to 120 degrees. Preferably, it is 90 to 120 degrees. At this angle, the flow guidance effect is outstanding, significantly improving the operating efficiency of the steel-slag separation process.

[0081] Understandably, the aforementioned included angle refers to Figure 3 c in the text.

[0082] In some of these implementations, please refer to Figure 3 The commutator 7 includes a molten steel guide plate 71 and a slag guide plate 72 connected to each other. The top edges of the molten steel guide plate 71 and the top edges of the slag guide plate 72 are connected to form a straight watershed 73. The molten steel guide plate 71 and the slag guide plate 72 are connected at an angle of 60 degrees to 120 degrees. The watershed 73 can be selectively located at the lower left or lower right of the outlet 12.

[0083] Using mechanical structures such as robotic arms, the commutator 7 can be moved horizontally left and right. Before the molten steel begins to flow, the molten steel guide plate 71 of the commutator 7 is positioned directly below the sealing plug 5 (the commutator 7 is in a position where...). Figure 2 In state a), the watershed 73 is located to the lower right of the tap hole 12; after the molten steel is discharged and the reducing slag begins to appear, the commutator 7 is quickly moved so that the slag guide plate 72 is located directly below the sealing plug 5 to receive the reducing slag (commutator 7 is in state a). Figure 2 In state b), the watershed 73 is located to the lower left of the tap hole 12, and the reducing slag slides down the slag guide plate 72 to the top of the blast port 8. This commutator 7 promotes the complete separation of molten steel and reducing slag, has a simple structure, is flexible and mobile, and realizes the continuity of the steel-slag separation process.

[0084] In some embodiments, the commutator 7 is made of refractory material.

[0085] In some embodiments, the steel slag treatment equipment further includes an air quenching device, the air outlet 8 of which faces the slag discharge end of the commutator 7, i.e., towards the slag discharge end of the steel slag guide plate 72. By utilizing the air-quenched reducing slag in the slag collection chamber to collect reducing slag particles, and by opening the valve of the hopper silo, the reducing slag is allowed to fall freely into the slag pot under gravity, enabling rapid transfer of the high-temperature reducing slag in the slag collection chamber and achieving continuous production.

[0086] Furthermore, the air outlet 8 is the air outlet nozzle of the air quenching device.

[0087] In some embodiments, the steel slag treatment equipment further includes a slag collection device 9, which includes a slag collection chamber 91. The slag collection chamber 91 has a steel slag inlet 92, a steel slag outlet 93, and a dust discharge port 94. The steel slag outlet 93 is connected to the slag tank 4.

[0088] In some embodiments, the steel slag treatment equipment operates as follows:

[0089] Please see Figure 2 A reducing agent is injected into the molten steel slag in the reducing ladle 1 through a rotary jetting device to carry out a reduction reaction. The rotary nozzle of the rotary jetting device extends from the connection port 11 of the reducing ladle 1 into the molten steel slag and performs rotary jetting for 6-10 minutes. During this time, the reduced molten steel 101, being denser than the reducing slag 102, accumulates at the bottom of the reducing ladle 1. Then, the reducing ladle 1 is hoisted to the platform 10, and a heating device is placed on the connection port 11 of the reducing ladle 1. The heating device is fixed by a bracket 100 on the platform 10. Gas is supplied to the heating device via a gas pipe 21 to heat and maintain the temperature of the mixture after rotary jetting, controlling the temperature above 1420℃ for 20-30 minutes. Next, the sealing plug fixing plate 6 is pushed open so that it no longer presses against the sealing plug 5. The sealing plug 5 is then placed between the molten steel 101 and the reducing slag 102. 02 Under double static pressure, the molten steel 101 falls freely onto the molten steel guide plate 71 of the commutator 7 and slides down the molten steel guide plate 71 into the receiving ladle 3. After the molten steel 101 is discharged, the commutator 7 is quickly moved so that the slag guide plate 72 on it is directly below the steel outlet 12. The reducing slag 102 slides down the slag guide plate 72 to the air outlet 8 of the air quenching device. The molten reducing slag 102 is torn into slag particles with a diameter of <10mm by a large amount of high-pressure air sprayed from the air outlet 8. The slag particles are then sprayed into the slag collection chamber 91 by the high-pressure air through the slag inlet 92 and accumulate in the bucket-shaped bin 95 at the bottom of the slag collection chamber 91. The dust and flue gas are discharged through the dust removal pipe at the dust outlet 94 at the top of the slag collection chamber 91 and enter the dust removal system for treatment. After the slag particles in the bucket-shaped bin 95 are full, the valve 96 is opened to release the slag particles into the slag tank 4 and transport them to the next process.

[0090] in, Figure 2 The system integrates two working states: collecting molten steel and collecting reducing slag.

[0091] The following are specific examples.

[0092] Example 1

[0093] At the converter slag processing station of the steel enterprise, a reduction ladle 1 with an inner diameter of 3.8m and a height of 3.5m is used to hold 15t to 18t of hot molten steel slag after tapping from the 210t converter; the temperature of the molten steel slag is 1600℃.

[0094] The reduced ladle 1 is then transported to the rotary jet cleaning station. Carbon powder is injected into the molten steel slag in the reduced ladle 1 through a rotary jet cleaning device to carry out the reduction reaction. The rotary nozzle of the rotary jet cleaning device extends into the molten steel slag from the connection port 11 of the reduced ladle 1 to perform rotary jet cleaning. At this time, the reduced molten steel 101, due to its density being greater than that of the reduced slag 102, gathers at the bottom of the reduced ladle 1. The rotary jet cleaning time is 8 minutes. The rotation speed is 85 rpm for the first 5 minutes and the cleaning speed is 35 kg / min·ton slag for the first 5 minutes. The rotation speed is 125 rpm for the last 3 minutes and the cleaning speed is 45 kg / min·ton slag for the last 3 minutes.

[0095] Then, the reducing ladle 1 is hoisted to the slag treatment platform 10, and a heating device is placed on the connection port 11 of the reducing ladle 1, using fuel gas with a value of 10000 J / Nm³. 3 The flow rate is 500 Nm 3 / h, mixed coal gas at a pressure of 3000Pa is used to heat and hold the molten steel slag at a temperature above 1420℃ for 20 minutes, so that the molten steel 101 can be fully gathered at the bottom of the reduction ladle 1; wherein the holding temperature is 1500℃ and the holding time is 20 minutes.

[0096] Next, push open the sealing plug fixing plate 6 so that it no longer blocks the sealing plug 5. The sealing plug 5 falls off under the dual static pressure of the molten steel 101 and the reducing slag 102. The molten steel 101 falls freely onto the molten steel guide plate of the commutator 7 and slides down the molten steel guide plate into the receiving ladle 3.

[0097] After the molten steel 101 is discharged, the reversing device 7 is quickly moved so that the slag guide plate 72 is directly below the steel outlet 12. The reducing slag 102 slides down the slag guide plate 72 to the top of the air quenching device's blower 8. The molten reducing slag 102 is torn into slag particles with a diameter of <10mm by a large amount of high-pressure air sprayed from the blower 8, and then sprayed into the slag collection chamber 91 through the slag inlet 92, accumulating in the hopper-shaped bin 95 at the bottom of the slag collection chamber 91. The pressure of this high-pressure air is 0.4MPa and the air volume is 80000Nm. 3 / h;

[0098] After the air quenching device finishes spraying, the air nozzle is closed, the valve 96 of the bucket hopper 95 is opened, and the granular steel slag is released into the slag hopper 4 and transported to the next process for processing; the dust and flue gas are discharged through the dust removal pipe at the dust discharge port 94 at the top of the slag collection chamber 91 and enter the dust removal system for processing.

[0099] Example 2

[0100] Example 2 is basically the same as Example 1, except that: the rotational blowing time is 10 min, the rotational speed is 90 rpm in the first 5 min, the blowing speed is 40 (kg / min·ton slag) in the first 5 min, the rotational speed is 130 rpm in the last 5 min, and the blowing speed is 50 (kg / min·ton slag) in the last 5 min; during heating and heat preservation, the heat preservation temperature is 1420℃, and the heat preservation time is 30 min.

[0101] Example 3

[0102] Example 3 is basically the same as Example 1, except that the rotation speed is 110 revolutions / min during the first 5 minutes of rotary spraying.

[0103] Example 4

[0104] Example 4 is basically the same as Example 1, except that: during rotary injection, the injection speed is 50 (kg / min·ton of slag) in the first 5 minutes.

[0105] Example 5

[0106] Example 5 is basically the same as Example 1, except that the rotational blowing time is 15 minutes.

[0107] Example 6

[0108] Example 6 is basically the same as Example 1, except that the heat preservation temperature is 1400℃.

[0109] Example 7

[0110] Example 7 is basically the same as Example 1, except that the heat preservation time is 10 minutes.

[0111] The reduction slags from Examples 1 to 7 were tested for the mass content of FeO and P2O5. The mass content of FeO in the reduction slag decreased from 20% to 25% to 4% to 6%, and the mass content of P2O5 decreased from 1.2% to 2.2% to 0.1% to 0.24%. This effectively improved the recovery rate of molten steel and the recycling rate of steel slag, thereby improving economic benefits and reducing environmental pollution.

[0112] Furthermore, during rotary jet cleaning, higher steel recovery rates were achieved when the jetting time was 6-8 minutes, or when the rotary jetting speed was 80-90 rpm for ≤5 minutes and 120-130 rpm for >5 minutes, or when the rotary jetting speed was 30-40 kg / min·ton slag for ≤5 minutes and 41-50 kg / min·ton slag for >5 minutes. Even higher steel recovery rates were obtained at holding temperatures of 1420℃-1500℃ or holding times of 20-30 minutes.

[0113] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0114] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A steel slag treatment device, characterized in that, Includes a reduction ladle, a rotary jetting device, and a heating device; The reduction ladle is used to hold molten steel slag; The rotary jetting device is used to rotary jet a reducing agent onto the molten steel slag in the reducing ladle for a reduction reaction; The heating device is used to heat the reduced steel ladle.

2. The steel slag treatment equipment as described in claim 1, characterized in that, The steel slag processing equipment also includes a sealing plug and a sealing plug fixing plate. The reducing steel ladle is provided with a steel outlet. The sealing plug is used to seal the steel outlet. The sealing plug fixing plate is used to be located on the outside of the sealing plug and to fix the sealing plug when the sealing plug seals the steel outlet. The sealing plug fixing plate can be slidably connected to the reducing steel ladle to be close to or away from the steel outlet.

3. The steel slag treatment equipment as described in any one of claims 1 to 2, characterized in that, The steel slag processing equipment also includes a receiving ladle and a slag pot; the reducing ladle has a connection port and a steel outlet at the bottom; the connection port can be selectively connected to the rotary jetting device or the heating device, and the steel outlet can be selectively connected to the receiving ladle or the slag pot.

4. The steel slag treatment equipment as described in claim 3, characterized in that, The steel slag processing equipment also includes a reversing device located below the reducing ladle. The steel outlet can be selectively connected to the receiving ladle or the slag pot via the reversing device.

5. The steel slag treatment equipment as described in claim 4, characterized in that, The commutator includes a molten steel guide section and a slag guide section connected to each other. The commutator is movable relative to the reducing ladle so that the molten steel guide section or the slag guide section is selectively configured to correspond to the steel outlet.

6. The steel slag treatment equipment as described in claim 5, characterized in that, Both the molten steel guide section and the slag guide section are guide surfaces, and the molten steel guide section and the slag guide section are connected to form an angle. The molten steel guide section is inclined from top to bottom toward the receiving ladle, and the slag guide section is inclined from top to bottom toward the slag pot.

7. The steel slag treatment equipment as described in any one of claims 5 to 6, characterized in that, The molten steel guide section and the slag guide section form an angle of 60 degrees to 120 degrees.

8. The steel slag treatment equipment as described in claim 1, characterized in that, The rotary jetting device is a rotary spray gun.

9. The steel slag treatment equipment as described in claim 4, characterized in that, The steel slag treatment equipment also includes an air quenching device, the air outlet of which faces the slag discharge end of the commutator.

10. The steel slag treatment equipment according to any one of claims 1 to 2, characterized in that, The steel slag treatment equipment also includes a slag collection device, which includes a slag collection chamber with a steel slag inlet, a steel slag outlet and a dust discharge port. The steel slag outlet is connected to a slag pot.

Images