Method for hot delivery of direct reduced iron to matched electric furnace

Abstract

The invention discloses a conveying method for hot delivery of direct reduced iron to a matched electric furnace, which is realized based on a conveying system, and the conveying system comprises a surge bin, a charging bucket, a trolley, a hoisting shaft and a movable hoister; in the initial state, the trolley bears the empty charging bucket to wait at the charging position of the surge bin, the hot-state DRI is discharged into the surge bin through the shaft furnace, the surge bin discharges the empty charging bucket, the charging bucket is conveyed to the position of the hoisting shaft through the trolley after being full, and the mobile hoister hoists the charging bucket containing the hot-state DRI from the charging bucket trolley and transversely moves the charging bucket to the position above the hot charging bucket of the matched electric furnace. And the charging bucket is controlled to be in butt joint with the hot material bin, the hot-state DRI is loaded into the hot material bin, after loading is completed, the elevator transports the empty charging bucket back to the trolley, and the trolley returns to the charging position of the surge bin. By the adoption of the conveying method, the operation cost is low, adaptability is higher, the problems of the discharging rhythm, the straight-through space and equipment abrasion do not need to be considered too much, the equipment failure rate is low, and maintenance is easy and convenient.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of hot delivery, and particularly relates to a method for transporting hot direct reduced iron (DRI) by using a material tank. BACKGROUND

[0002] Under the background of carbon neutralization and carbon peak, the production of direct reduced iron and other low-carbon metallurgical process technologies by shaft furnace gradually enters the field of vision. Most steel plants use the production of cold direct reduced iron as the raw material of the electric furnace. The process of producing cold direct reduced iron is to cool the high-temperature DRI at about 680 DEG C to about 80 DEG C. Although the cold direct reduced iron is convenient for transportation and can prevent the secondary oxidation of the reduced iron, the investment of the product cooling system needs to be increased, and importantly, the power consumption and smelting time of the electric furnace are increased.

[0003] In recent years, foreign steel plants have developed a direct reduced iron hot delivery process, which can be directly sent to the matching electric furnace without cooling. The foreign developed hot delivery technology mainly has pneumatic conveying and sealed heat-resistant chain bucket machine conveying two forms. These two forms of conveying methods can meet the needs of production, but there are still the following shortcomings.

[0004] The pneumatic conveying is to use nitrogen as the medium for conveying, and is provided with a nitrogen cooling and washing device, a compressor and a heating device, etc. The investment and operation cost of the pneumatic conveying scheme are relatively high.

[0005] The sealed heat-resistant chain bucket machine conveying is to use the heat-resistant chain bucket machine to convey in the nitrogen sealed environment. This scheme requires that there is sufficient straight-through space between the shaft furnace and the electric furnace, and also requires that the discharging rhythm of the shaft furnace is adapted to the continuous and uniform conveying system of the chain bucket machine. In addition, the chain bucket machine runs in a sealed dust-containing environment, the equipment wear and failure rate are relatively high, and the maintenance is relatively troublesome. SUMMARY

[0006] The present application aims to provide a conveying system and method for hot delivery of direct reduced iron to a matching electric furnace, which has low operation cost and strong adaptability.

[0007] In order to achieve the above technical purpose, the present application adopts the following technical scheme: a conveying method for hot delivery of direct reduced iron to a matching electric furnace, characterized in that it is realized based on a conveying system, and the conveying system comprises a buffer bin, a material tank, a trolley, a hoist shaft and a mobile hoist; in the initial state, the trolley carries an empty material tank at the buffer bin loading position, hot DRI is discharged from the shaft furnace into the buffer bin, the buffer bin discharges into the empty material tank, and after the material tank is filled, the trolley transports the material tank to the hoist shaft position, the mobile hoist lifts the material tank filled with hot DRI from the material tank trolley and transversely moves to above the hot material bin of the matching electric furnace, the material tank and the hot material bin are controlled to complete the butt joint and the hot DRI is loaded into the hot material bin, after the loading is completed, the hoist transports the empty material tank back to the trolley, and the trolley returns to the buffer bin loading position.

[0008] Further, the tank comprises a tank shell, a lifting rod installed on the tank shell and a weighing base; an inlet door and an outlet door are respectively arranged on the upper and lower portions of the tank shell.

[0009] Further, the tank shell is composed of a steel plate, a profile steel frame and a heat-resistant and wear-resistant lining plate.

[0010] Further, the trolley comprises a trolley main frame for carrying the tank, rollers installed on the trolley frame and a walking driving device, a trolley walking track is arranged between the buffer bin and the lifting well, and the walking driving device can drive the rollers to rotate so as to move the trolley along the trolley walking track.

[0011] Further, a tank rotating device is further installed on the trolley, and the tank rotating device can drive the tank to rotate.

[0012] Further, a guide track for lifting the tank is further installed on the trolley, and a guide roller is arranged on the tank and matched with the guide track.

[0013] Further, an automatic alignment device is arranged outside the corresponding trolley walking track below the lifting well.

[0014] Further, the mobile lifting machine comprises a frame, a lifting mechanism and a walking mechanism; the lifting mechanism is installed on the upper portion of the frame and connected with the tank through a steel wire rope and a lifting tool, and is used for driving the tank to ascend or descend; and the walking mechanism is installed on the lower portion of the frame and is used for driving the frame and the lifting mechanism to move laterally.

[0015] The method has the advantages that: the operation cost is low, the adaptability is stronger, the problems of discharging rhythm, straight-through space and equipment wear are not needed to be considered, the equipment failure rate is low, and the maintenance is simple and convenient. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0017] Figure 1 The structure of the present application is shown in the figure.

[0018] In the figure: 1-buffer bin; 2-tank; 3-trolley; 4-trolley walking track; 5-lifting well; 6-mobile lifting machine; 7-lifting machine walking track; 8-hot material bin. DETAILED DESCRIPTION

[0019] In order to make the technical problems, technical solutions and beneficial effects of the present application clearer, the present application will be further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application and not to limit the present application.

[0020] The present application is a conveying method for hot direct reduced iron to a matched electric furnace, which is realized based on a conveying system. Figure 1 As shown in the figure, the conveying system comprises a buffer bin 1, a material tank 2, a trolley 3, a trolley running track 4, a hoist 5, a mobile hoist 6 and a hoist running track 7. The buffer bin 1 is used for receiving and temporarily storing the hot DRI discharged from the shaft furnace; the material tank 2 is used for receiving and storing the hot DRI discharged from the buffer bin 1; the trolley 3 transports the material tank 2 back and forth between the buffer bin 1 and the hoist 5. An automatic alignment device is arranged outside the corresponding trolley running track below the hoist 5. By arranging the automatic alignment device, when the material tank 2 is transported to the position of the mobile hoist 5, the trolley 3 can stop at the accurate lifting position.

[0021] Specifically, the above-mentioned material tank 2 comprises a material tank shell, a lifting rod installed on the material tank shell and a weighing base; a feeding door and a discharging door are arranged on the upper and lower parts of the material tank shell, respectively. The material tank shell is composed of a steel plate, a profile steel frame and a heat-resistant and wear-resistant lining plate. By arranging the weighing base, the weight of the material tank is measured in real time during the loading process to control the loading amount. The whole process of loading and unloading and storing should be kept sealed to prevent secondary oxidation.

[0022] The above-mentioned trolley 3 comprises a trolley main frame for carrying the material tank, rollers installed on the trolley frame and a running driving device, a trolley running track 4 is laid between the buffer bin and the hoist, and the running driving device can drive the rollers to rotate, so that the trolley moves along the trolley running track 4. Preferably, the trolley 3 is also provided with a material tank rotating device, which can rotate the material tank during loading to ensure the uniformity of loading. A guide rail for lifting the material tank 2 is also installed on the trolley 3, and a guide roller is arranged on the material tank 2 to cooperate with the guide rail. When the material tank 2 is lifted or lowered, the guide can be realized through the cooperation of the guide roller and the guide rail.

[0023] Further, the above-mentioned mobile hoist 6 comprises a vehicle frame, a lifting mechanism and a running mechanism; the lifting mechanism is installed on the upper part of the vehicle frame and connected with the material tank through a steel wire rope and a lifting tool, and is used for driving the material tank to rise or fall; the running mechanism is installed on the lower part of the vehicle frame and is used for driving the vehicle frame and the lifting mechanism to move laterally.

[0024] The specific conveying method process of the present application is as follows: In the initial state, the trolley 3 carries the empty ladle 2 in the loading position of the buffer bin 1. The hot DRI discharged from the shaft furnace is injected into the buffer bin for temporary storage. During loading, the telescopic chute connected to the outlet valve of the buffer bin is lowered into the ladle 2, and then the ladle is filled until it is full. Then the ladle full of hot DRI is sent to the lifting position of the hoist 5 by the trolley 3. The movable hoist 6 lowers the lifting tool to connect with the ladle 2, and then lifts the ladle 2 full of hot DRI. After the lifting is completed, the movable hoist 6 moves along the hoist track 7 to above the hot material bin 8 for feeding the electric furnace, and then controls the ladle 2 to dock with the top feeding port of the hot material bin 8, and unloads the hot DRI into the hot material bin, completing the unloading work. After the unloading is completed, the movable hoist 6 lifts the empty ladle and returns to the hoist 5, and then the empty ladle is placed on the waiting trolley 3. Then the trolley 3 loads the empty ladle and returns to the loading position of the buffer bin. One cycle of hot DRI conveying is completed, and the cycle is repeated.

[0025] Compared with pneumatic conveying, only nitrogen consumption and power consumption are required in the method, the process is relatively simple, the operation cost is relatively low, the operation cost is about 25% of that of pneumatic conveying, the temperature drop of the hot material during conveying is about 50℃, which is similar to the pneumatic conveying scheme. Compared with the sealed heat-resistant chain bucket machine conveying, the process arrangement and adaptability are stronger, and it is not necessary to consider the problems of discharge rhythm, straight-through space and equipment wear and tear, the equipment failure rate is low, and the maintenance is simple and convenient.

[0026] The above describes the preferred embodiments of the present application. It should be noted that for those skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, which should also be considered as the protection scope of the present application.

Claims

1. A method of delivering hot direct reduced iron to a matched electric furnace, characterized in that, Based on the conveying system implementation, the conveying system comprises a buffer bin, a ladle, a trolley, a hoist shaft and a mobile hoist; In the initial state, the trolley carries empty ladles at the buffer bin loading position, hot DRI is discharged from the shaft furnace into the buffer bin, the buffer bin is discharged into the empty ladle, the ladle is full and is transported by the trolley to the hoist shaft position, the mobile hoist lifts the ladle containing hot DRI from the ladle trolley and transversely moves to above the hot material bin of the matched electric furnace, controls the ladle and the hot material bin to complete the butt joint and loads the hot DRI into the hot material bin, after the loading is completed, the hoist transports the empty ladle back to the trolley, and the trolley returns to the buffer bin loading position.

2. A delivery system for hot direct reduced iron to a matched electric furnace according to claim 1, characterized in that: The ladle comprises a ladle shell, a lifting pull rod mounted on the ladle shell and a weighing base; the upper and lower parts of the ladle shell are respectively provided with an inlet door and an outlet door.

3. A delivery system for hot direct reduced iron to a matched electric furnace as claimed in claim 2, characterized in that: The ladle shell is composed of a steel plate, a section steel frame and a heat-resistant and wear-resistant lining plate.

4. A delivery system for hot direct reduced iron to a matched electric furnace as claimed in claim 1, characterized in that: The trolley comprises a trolley main frame for carrying the ladle, a roller mounted on the trolley frame and a walking driving device, a trolley walking track is laid between the buffer bin and the hoist shaft, and the walking driving device can drive the roller to rotate, so that the trolley moves along the trolley walking track.

5. The delivery system for hot direct reduced iron to a matched electric furnace according to claim 1, characterized in that: The trolley is also provided with a ladle rotating device, which can drive the ladle to rotate.

6. A delivery system for hot direct reduced iron to a matched electric furnace as claimed in claim 1, characterized in that: The trolley is also provided with a ladle lifting guide rail, and the ladle is provided with a guide roller matched with the guide rail.

7. A delivery system for hot direct reduced iron to a matched electric furnace as claimed in claim 4, characterized in that: An automatic alignment device is arranged outside the corresponding trolley walking track on the outside of the hoist shaft.

8. A delivery system for hot direct reduced iron to a matched electric furnace according to any one of claims 1 to 7, characterized in that: The mobile hoist comprises a vehicle frame, a lifting mechanism and a walking mechanism; the lifting mechanism is mounted on the upper part of the vehicle frame and is connected with the ladle through a steel wire rope and a lifting tool, and is used to drive the ladle to ascend or descend; the walking mechanism is mounted on the lower part of the vehicle frame and is used to drive the vehicle frame and the lifting mechanism to move transversely.

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