Preparation method of red mud cold-pressed pellets

Abstract

The invention relates to the technical field of smelting additives, and discloses a preparation method of red mud cold-pressed pellets, which comprises the following steps: S1, raw material preparation: firstly, putting a raw material Bayer process red mud to be treated at a specified position so as to be conveniently treated by subsequent workers; a worker can adopt a manual pouring mode and can also adopt mechanical equipment to pour the materials into the stock bin (1). Compared with the prior art, the method has the following advantages and effects that the Bayer process red mud has large dispersity and is not prone to coalescence, red mud particles can be firmly bonded together by spraying the red mud cold-pressed pellet adhesive, the plasticity and the forming effect of the pellets are remarkably improved, the compressive strength and the wear resistance of the pellets are remarkably improved, and meanwhile the service life of the pellets is prolonged. After the adhesive is added, the pellet forming effect is very stable, the energy consumption is reduced, the production efficiency is improved, in addition, the pellet granularity is uniform, the wet pellet falling strength is more than 1.5 m < 2 > times and is complete, the dry pellet compressive strength reaches more than 100 kg, the cold strength is good, and the furnace burden requirement can be met.

Description

Technical Field

[0001] The invention relates to the technical field of smelting additives, and in particular to a method for preparing red mud cold-pressed pellets. Background Art

[0002] The metallurgical industry is an intensive consumer of raw materials for my country's industrial sector, and it is also a producer of a large amount of powdered waste. Among them, my country's alumina industry produces about 100 million tons of industrial waste slag-red mud annually, and the cumulative stockpile of red mud has reached 500 million tons. At present, although there are many ways to comprehensively utilize red mud, the comprehensive utilization rate is only about 5%. Most of the remaining red mud is directly stored, which not only wastes resources but also harms the environment. Therefore, how to reasonably optimize and efficiently utilize red mud resources is a problem that many researchers are concerned about. Red mud contains useful resources such as iron oxide, aluminum oxide, and calcium oxide, which can be used in steel smelting. However, due to their small particles, if they are directly recycled into the furnace, the furnace condition will deteriorate. They need to be agglomerated first so that the physical and chemical properties and metallurgical properties of these materials meet the requirements for furnace smelting.

[0003] However, the existing methods for preparing red mud cold-pressed pellets have the problems of low pellet forming rate, uneven particle size, low wet ball drop strength, and poor dry ball compressive strength. Summary of the invention

[0004] The purpose of the present invention is to provide a method for preparing red mud cold-pressed pellets, which can solve the problems raised in the above background technology.

[0005] The above technical objectives of the present invention are achieved through the following technical solutions: a method for preparing red mud cold-pressed pellets, comprising a silo, a drying furnace, a first conveyor belt, a second conveyor belt and a pellet press, one side of the silo is fixedly connected to a motor box, the inside of the motor box is fixedly connected to a motor, the output end of the motor is fixedly connected to a rotating shaft, the surface of the rotating shaft is fixedly connected to a stirring blade, one side of the upper surface of the silo is fixedly connected to a water tank, the other side of the upper surface of the silo is provided with a feed inlet, and the lower part of one side of the silo is provided with a discharge port, the inside of the drying furnace is fixedly connected to a bracket, the upper surface of the bracket is fixedly connected to a third conveyor belt, the other side of the silo is fixedly connected to a fourth conveyor belt, the lower surface of the fourth conveyor belt is fixedly connected to a fixed frame, one side of the fixed frame is fixedly connected to a support frame, and the upper surface of the support frame is fixedly connected to a fifth conveyor belt.

[0006] The present invention is further configured as follows: a support leg is fixedly connected to the lower surface of the silo, and a connecting rod is fixedly connected to one side of the support leg.

[0007] By adopting the above technical solution, the supporting legs and the connecting rods play the role of supporting and fixing.

[0008] The present invention is further configured as follows: the number of the supporting legs is four, and the four supporting legs are fixedly connected to the left and right sides of the lower surface of the silo in the form of a rectangular array.

[0009] By adopting the above technical solution, the arrangement of four supporting legs makes the stability higher.

[0010] The present invention is further configured as follows: a support sheet is fixedly connected to the bottom end of the support leg, and a protection pad is fixedly connected to the lower surface of the support sheet.

[0011] By adopting the above technical solution, the setting of the support sheet plays a role in supporting the support legs, thereby increasing the contact area with the ground.

[0012] The present invention is further configured as follows: a vertical rod is fixedly connected to the lower surface of the drying oven, and a fixing plate is fixedly connected to the bottom end of the vertical rod.

[0013] By adopting the above technical solution, the vertical rods and the fixing plates play a role in supporting and fixing the drying furnace.

[0014] The present invention is further configured as follows: a hole is provided on the upper surface of the fixing plate, and a bolt is inserted into the hole.

[0015] By adopting the above technical solution, the setting of the bolts can fix the fixing plate on the ground.

[0016] The present invention is further configured as follows: a sixth conveyor belt is fixedly connected to one side of the ball press machine, and a support rod is fixedly connected to the lower surface of the sixth conveyor belt.

[0017] By adopting the above technical solution, the support rod plays a role in supporting the sixth conveyor belt.

[0018] The present invention is further configured as follows: a hot air blower is fixedly connected to the interior of the drying furnace, and an air outlet hood is fixedly connected to one side of the hot air blower.

[0019] By adopting the above technical solution, the hot air blower plays a drying role.

[0020] The present invention is further configured as follows: lower surfaces of the first conveyor belt and the second conveyor belt are both fixedly connected to support rods, and one side of the support rods is fixedly connected to a fixing rod.

[0021] By adopting the above technical solution, the fixing rod and the supporting rod play a role in supporting the first conveyor belt and the second conveyor belt, thereby improving the overall stability.

[0022] The present invention is further provided as follows: a method for preparing red mud cold-pressed pellets, comprising the following steps:

[0023] S1: Raw material preparation. First, the raw material Bayer red mud to be processed is placed in a designated location for subsequent workers to process it. Workers can use manual dumping or mechanical equipment to dump it into the silo;

[0024] S2: Material batching, the material poured into the silo is conveyed to the batching machine for batching. After the batching is completed, it is conveyed to the next process through the conveying device for mixing and stirring. When the material is conveyed by the conveying device, the red mud cold-pressed pellet binder is evenly sprayed on the conveying device. Since the Bayer process red mud has a large dispersion and is not easy to agglomerate with each other, the red mud particles can be firmly bonded together by spraying the red mud cold-pressed pellet binder, which significantly improves the plasticity and molding effect of the pellets, as well as the compressive strength and wear resistance of the pellets. At the same time, after adding the binder, the pellet molding effect can be very stable, and the energy consumption can be reduced and the production efficiency can be improved;

[0025] S3: Mixing and stirring. The material with the adhesive added is sent to the No. 1 stirring device through a conveying device for the first mixing and stirring, and the stirring time is 2 minutes. During the first mixing and stirring process, a proper amount of water is sprayed at the tail end of the No. 1 stirring device. After the water is added and stirred, it is sent to the No. 2 stirring device again through a conveying device for stirring. Similarly, the stirring time is 2 minutes. After being stirred evenly, it is sent to the next process for processing;

[0026] S4: Ball pressing: The stirred material is transported to a ball press, where it is ball pressed to form wet red mud cold-pressed pellets;

[0027] S5: Drying, the wet red mud cold pressed pellets are transported to a drying furnace for drying, wherein the drying temperature is 150°C and the drying time is 2 hours. The temperature of 150°C and the drying time of 2 hours can effectively ensure the removal of free moisture in the wet red mud cold pressed pellets, and can improve the compressive strength of the green pellets. Moreover, the drying of the wet red mud cold pressed pellets under this condition not only effectively ensures the drying effect, but also improves the production efficiency and reduces the production cost.

[0028] S6: Finished product, after drying, the final finished product is obtained, the moisture content of the finished product is below 1%, and the moisture content of the finished red mud cold-pressed pellets is below 1%, which can form a tight structure inside the pellets, improve their physical properties, and at the same time, improve the convenience of storage and transportation. In addition, it can also improve the stability of metallurgical properties after being put into the furnace.

[0029] The present invention is further configured as follows: the Bayer process red mud is selected from Bayer process red mud having a total iron content of 50% and a moisture content of less than 13%.

[0030] The present invention is further configured as follows: the amount of the red mud cold-pressed pellets added is 2-3% of the Bayer process red mud.

[0031] The present invention is further configured as follows: the amount of water sprayed in step S3 is 8-10% of the red mud.

[0032] The beneficial effects of the present invention are as follows: first, Bayer red mud (with a total iron content of 50% and a moisture content of less than 13%) is poured into a silo by a forklift, and after quantitative batching, the red mud is evenly discharged onto a conveyor belt through an ash discharge valve at the bottom of the silo, and is conveyed via a first conveyor belt, and an appropriate amount of red mud pellet binder (the amount added is 2-3% of the red mud) is evenly sprayed on the first conveyor belt, and then the red mud pellet binder enters a first mixer together with the material for stirring (stirring time is about 2 minutes), and during the stirring process, an appropriate amount of water (the amount of water is 8%-10% of the red mud) is sprayed at the tail end of the silo, and then the material enters a second mixer, and is evenly stirred for a second time (stirring time is about 2 minutes), and then the material is conveyed via a conveyor belt. It enters the feeder and is then conveyed to the ball press for ball pressing through a vibrating belt. Qualified wet red mud pellets are conveyed to the drying furnace through a conveyor belt and dried in the drying furnace (drying temperature 150°C and drying time 2h) to obtain dry red mud pellets (moisture content below 1%). The dry red mud pellets enter the finished product warehouse through an elevator. After adding the cold-pressed pellet adhesive, the red mud particles can be firmly bonded together, which significantly improves the plasticity and molding effect of the pellets as well as the compressive strength and wear resistance of the pellets. At the same time, after adding the adhesive, the pellet molding effect can be very stable, and energy consumption can be reduced and production efficiency can be improved. In addition, the particle size of the pellets is uniform, the wet ball falling strength is 1.5m2 or more, the dry ball compressive strength is more than 100kg, the cold strength is good, and it can meet the requirements of the charge. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0034] Figure 1 It is a structural schematic diagram of the present invention;

[0035] Figure 2 It is a structural schematic diagram of the drying furnace of the present invention;

[0036] Figure 3 It is a structural schematic diagram of the ball press machine of the present invention;

[0037] Figure 4 It is a structural schematic diagram of the silo of the present invention;

[0038] Figure 5For the present invention Figure 1 The enlarged structural diagram at A in the middle;

[0039] Figure 6 For the present invention Figure 1 Enlarged structural diagram at B in the middle.

[0040] In the figure, 1. silo; 2. drying furnace; 3. first conveyor belt; 4. second conveyor belt; 5. ball press; 6. motor box; 7. water tank; 8. feed port; 9. discharge port; 10. bracket; 11. third conveyor belt; 12. fourth conveyor belt; 13. fixing frame; 14. supporting frame; 15. fifth conveyor belt; 16. supporting leg; 17. connecting rod; 18. vertical rod; 19. sixth conveyor belt; 20. supporting rod; 21. air outlet hood. DETAILED DESCRIPTION

[0041] The technical solution of the present invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] Reference Figure 1-6A method for preparing red mud cold-pressed pellets, comprising a silo 1, a drying furnace 2, a first conveyor belt 3, a second conveyor belt 4 and a pellet press 5, the lower surfaces of the first conveyor belt 3 and the second conveyor belt 4 are fixedly connected with a support rod, one side of the support rod is fixedly connected with a fixing rod, the lower surface of the silo 1 is fixedly connected with a support leg 16, the bottom end of the support leg 16 is fixedly connected with a support sheet, the lower surface of the support sheet is fixedly connected with a protective pad, one side of the support leg 16 is fixedly connected with a connecting rod 17, the number of the support legs 16 is four, and the four support legs 16 are fixedly connected to the left and right sides of the lower surface of the silo 1 in the form of a rectangular array, one side of the silo 1 is fixedly connected with a motor box 6, the inside of the motor box 6 is fixedly connected with a motor, the output end of the motor is fixedly connected with a rotating shaft, and the surface of the rotating shaft is fixedly connected with a stirring blade, a forklift is used to pour Bayer red mud (total iron content of 50%, moisture content less than 13%) into the silo, after quantitative batching, the red mud is evenly put into the conveyor belt by the ash discharge valve at the bottom of the hopper, and the red mud is evenly put into the conveyor belt by the first conveyor belt. The red mud pellets are conveyed and evenly sprayed with an appropriate amount of red mud pellet binder (2-3% of the red mud) on the first conveyor belt. Then the materials enter the first mixer together for stirring (stirring time is about 2 minutes). After spraying an appropriate amount of water (8%-10% of the red mud) at the tail end of the silo, the materials enter the second mixer. After secondary stirring (stirring time is about 2 minutes), the materials enter the feeder through the conveyor belt, and then are conveyed to the ball press machine through a vibrating belt for pressing. Qualified wet red mud pellets are dried by the conveyor belt through a drying furnace (drying temperature 150°C and drying time 2h) to obtain dry red mud pellets (water content below 1%) and enter the finished product warehouse through an elevator. After adding the cold-pressed pellet binder, the red mud particles can be firmly bonded together, which significantly improves the plasticity and molding effect of the pellets, as well as the compressive strength and wear resistance of the pellets. At the same time, after adding the binder, the pellet molding effect can be very stable, and energy consumption can be reduced and production efficiency can be improved. The pellet size is uniform, and the wet ball drop strength is 1.5m It is complete for more than 2 times, the dry ball compressive strength is more than 100kg, the cold strength is good, and it can meet the requirements of furnace charge.

[0043] Further, a water tank 7 is fixedly connected to one side of the upper surface of the silo 1, a feed port 8 is provided on the other side of the upper surface of the silo 1, a discharge port 9 is provided at the lower part of one side of the silo 1, a bracket 10 is fixedly connected to the inside of the drying furnace 2, a third conveyor belt 11 is fixedly connected to the upper surface of the bracket 10, a vertical rod 18 is fixedly connected to the lower surface of the drying furnace 2, a sixth conveyor belt 19 is fixedly connected to one side of the ball press 5, a support rod 20 is fixedly connected to the lower surface of the sixth conveyor belt 19, a hot air blower is fixedly connected to the inside of the drying furnace 2, an air outlet hood 21 is fixedly connected to one side of the hot air blower, a fixing plate is fixedly connected to the bottom end of the vertical rod 18, a hole is provided on the upper surface of the fixing plate, bolts are inserted into the holes, a fourth conveyor belt 12 is fixedly connected to the other side of the silo 1, a fixing frame 13 is fixedly connected to the lower surface of the fourth conveyor belt 12, a supporting frame 14 is fixedly connected to one side of the fixing frame 13, and a fifth conveyor belt 15 is fixedly connected to the upper surface of the supporting frame 14;

[0044] A method for preparing red mud cold-pressed pellets comprises the following steps:

[0045] S1: Raw material preparation, firstly, the raw material Bayer process red mud to be processed is placed in a designated location for subsequent workers to process it. Workers can use manual dumping or mechanical equipment to dump it into silo 1;

[0046] S2: material batching, the material poured into the silo 1 is conveyed to the batching machine for batching, and after the batching is completed, it is conveyed to the next process through the conveying device for mixing and stirring. When the material is conveyed by the conveying device, the red mud cold-pressed pellet binder is evenly sprayed on the conveying device. Since the Bayer process red mud has a large dispersion and is not easy to agglomerate with each other, the red mud particles can be firmly bonded together by spraying the red mud cold-pressed pellet binder, which significantly improves the plasticity and molding effect of the pellets, as well as the compressive strength and wear resistance of the pellets. At the same time, after adding the binder, the pellet molding effect can be very stable, and the energy consumption can be reduced and the production efficiency can be improved;

[0047] S3: Mixing and stirring. The material with the adhesive added is sent to the No. 1 stirring device through a conveying device for the first mixing and stirring, and the stirring time is 2 minutes. During the first mixing and stirring process, a proper amount of water is sprayed at the tail end of the No. 1 stirring device. After the water is added and stirred, it is sent to the No. 2 stirring device again through a conveying device for stirring. Similarly, the stirring time is 2 minutes. After being stirred evenly, it is sent to the next process for processing;

[0048] S4: Ball pressing: the stirred material is transported to the ball press 5, and the material is ball pressed by the ball press 5 to form wet red mud cold-pressed pellets;

[0049] S5: Drying, the wet red mud cold pressed pellets are transported to the drying furnace 2 for drying, wherein the drying temperature is 150°C and the drying time is 2 hours. The temperature of 150°C and the drying time of 2 hours can effectively ensure the removal of free moisture in the wet red mud cold pressed pellets, and can improve the compressive strength of the green balls. Moreover, the wet red mud cold pressed pellets are dried under this condition, which not only effectively ensures the drying effect, but also improves the production efficiency and reduces the production cost.

[0050] S6: Finished product, after drying, the final finished product is obtained, the moisture content of the finished product is below 1%, and the moisture content of the finished red mud cold-pressed pellets is below 1%, which can form a tight structure inside the pellets, improve their physical properties, and at the same time, improve the convenience of storage and transportation. In addition, it can also improve the stability of metallurgical properties after being put into the furnace.

[0051] Among them, the Bayer process red mud uses Bayer process red mud with a total iron content of 50% and a moisture content of less than 13%. The amount of red mud cold-pressed pellets added is 2-3% of the Bayer process red mud, and the amount of water sprayed is 8-10% of the red mud.

[0052] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing red mud cold-pressed pellets, characterized in that: The following steps are involved: S1: Raw material preparation, firstly, the raw material Bayer process red mud to be processed is placed in a designated location for subsequent workers to process it. Workers can use manual dumping or mechanical equipment to dump it into the silo (1); S2: material batching, the material poured into the silo (1) is conveyed to the batching machine for batching, and after the batching is completed, it is conveyed to the next process by the conveying device for mixing and stirring. When the material is conveyed by the conveying device, the red mud cold-pressed pellet binder is evenly sprayed on the conveying device. Since the Bayer process red mud has a large dispersion and is not easy to agglomerate with each other, the red mud particles can be firmly bonded together by spraying the red mud cold-pressed pellet binder, which significantly improves the plasticity and molding effect of the pellets, as well as the compressive strength and wear resistance of the pellets. At the same time, after adding the binder, the pellet molding effect can be very stable, and the energy consumption can be reduced and the production efficiency can be improved; S3: Mixing and stirring. The material with the adhesive added is sent to the No. 1 stirring device through a conveying device for the first mixing and stirring, and the stirring time is 2 minutes. During the first mixing and stirring process, a proper amount of water is sprayed at the tail end of the No. 1 stirring device. After the water is added and stirred, it is sent to the No. 2 stirring device again through a conveying device for stirring. Similarly, the stirring time is 2 minutes. After being stirred evenly, it is sent to the next process for processing; S4: briquetting: the stirred material is transported to a briquetting machine (5), and the material is briquetting by the briquetting machine (5) to form wet red mud cold-pressed pellets; S5: drying, the wet red mud cold pressed pellets are conveyed to a drying furnace (2) for drying, wherein the drying temperature is 150° C. and the drying time is 2 hours. The temperature of 150° C. and the drying time of 2 hours can effectively ensure the removal of free moisture in the wet red mud cold pressed pellets, thereby improving the compressive strength of the green pellets. Furthermore, the drying of the wet red mud cold pressed pellets under such conditions not only effectively ensures the drying effect, but also improves the production efficiency and reduces the production cost. S6: Finished product, after drying, the final finished product is obtained, the moisture content of the finished product is below 1%, and the moisture content of the finished red mud cold-pressed pellets is below 1%, which can form a tight structure inside the pellets, improve their physical properties, and at the same time, improve the convenience of storage and transportation. In addition, it can also improve the stability of metallurgical properties after being put into the furnace.

2. The method for preparing red mud cold-pressed pellets according to claim 1, characterized in that: The Bayer process red mud is selected from Bayer process red mud with a total iron content of 50% and a moisture content of less than 13%.

3. The method for preparing red mud cold-pressed pellets according to claim 1, characterized in that: The amount of the red mud cold-pressed pellets added is 2-3% of the Bayer red mud.

4. The method for preparing red mud cold-pressed pellets according to claim 1, characterized in that: The amount of water sprayed in step S3 is 8-10% of the red mud.

5. The method for preparing red mud cold-pressed pellets according to any one of claims 1 to 4, characterized in that: It also includes a silo (1), a drying furnace (2), a first conveyor belt (3), a second conveyor belt (4) and a ball press (5); one side of the silo (1) is fixedly connected to a motor box (6); the interior of the motor box (6) is fixedly connected to a motor; the output end of the motor is fixedly connected to a rotating shaft; the surface of the rotating shaft is fixedly connected to a stirring blade; one side of the upper surface of the silo (1) is fixedly connected to a water tank (7); the other side of the upper surface of the silo (1) is provided with a feed port (8); the lower part of one side of the silo (1) is provided with a discharge port (9); the drying furnace A bracket (10) is fixedly connected to the interior of the silo (2); a third conveyor belt (11) is fixedly connected to the upper surface of the bracket (10); a fourth conveyor belt (12) is fixedly connected to the other side of the silo (1); a fixed frame (13) is fixedly connected to the lower surface of the fourth conveyor belt (12); a support frame (14) is fixedly connected to one side of the fixed frame (13); a fifth conveyor belt (15) is fixedly connected to the upper surface of the support frame (14); a support leg (16) is fixedly connected to the lower surface of the silo (1); and a support leg (16) is fixedly connected to one side of the support leg (16). The drying furnace (2) is fixedly connected with a connecting rod (17), the number of the supporting legs (16) is four, and the four supporting legs (16) are fixedly connected to the left and right sides of the lower surface of the silo (1) in the form of a rectangular array, the number of the supporting legs (16) is four, and the four supporting legs (16) are fixedly connected to the left and right sides of the lower surface of the silo (1) in the form of a rectangular array, the bottom end of the supporting leg (16) is fixedly connected with a supporting sheet, and the lower surface of the supporting sheet is fixedly connected with a protective pad, and the lower surface of the drying furnace (2) is fixedly connected with a vertical rod (18), and the vertical rod The bottom end of (18) is fixedly connected to a fixing plate, the upper surface of the fixing plate is provided with a hole, a bolt is inserted into the hole, one side of the ball press (5) is fixedly connected to a sixth conveyor belt (19), the lower surface of the sixth conveyor belt (19) is fixedly connected to a support rod (20), the interior of the drying furnace (2) is fixedly connected to a hot air blower, one side of the hot air blower is fixedly connected to an air outlet hood (21), the lower surfaces of the first conveyor belt (3) and the second conveyor belt (4) are both fixedly connected to a support rod, one side of the support rod is fixedly connected to a fixing rod.

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