Energy-saving smelting system for industrial silicon
By introducing a rotary kiln into the industrial silicon smelting system to preheat the charge, the problem of high energy consumption in submerged arc furnace smelting was solved, achieving significant energy savings.
Patent Information
- Application Number
- CN202422678490.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-04
- Publication Date
- 2025-10-21
- Estimated Expiration
- 2034-11-04
AI Technical Summary
During the industrial silicon smelting process, a large amount of electricity is consumed to raise the temperature of the charge entering the blast furnace, resulting in increased energy consumption.
A rotary kiln is added between the mixing chamber and the submerged arc furnace. The mixed charge is preheated by the rotary kiln, raising its temperature from room temperature to 1000°C, reducing the need to increase the temperature inside the submerged arc furnace.
The electricity consumption per ton of the submerged arc furnace has been reduced, saving production costs. Specifically, 400,000 yuan in electricity bills can be saved every day, and 13.2 million yuan can be saved annually.
Smart Images
Figure CN223460824U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the industrial silicon smelting technical field, concretely relates to an energy -conserving smelting system of industrial silicon. BACKGROUND
[0002] In the traditional process of smelting industrial silicon in the electric furnace, the silica will be washed clean with medicine water as smelting raw material, then through washing fine coal as reducing agent, according to product composition, furnace condition, wood block and charcoal are added for mixing. The mixed raw material enters the top bin through the soft rubber belt conveyor, and then enters the electric furnace for smelting through the automatic feeding pipe. The normal temperature of the furnace charge is 25 DEG C, the melting point of silica is above 1720 DEG C, and the reduction temperature is about 1670 DEG C. A large amount of electric energy is consumed to raise the temperature of the material from 25 DEG C to about 1700 DEG C, and the temperature of the crucible area is even as high as 2000 DEG C. Therefore, the ton electric consumption of the electric furnace for producing industrial silicon is as high as about 13000 kWh. In view of this, in the energy saving and consumption reducing measures in the related metallurgical field, there is a smelting application using a direct current electric furnace. The theoretical advantage of the direct current electric furnace over the alternating current electric furnace is that the short network is cancelled and the reactive power loss is reduced to increase the power factor. However, there is no example of using the direct current electric furnace in the industrial silicon large-scale electric furnace, and from the smelting of steel, silicon manganese alloy and other products by the direct current electric furnace, although the power factor of the direct current electric furnace is increased, the ton electric consumption is not greatly improved. SUMMARY
[0003] The utility model discloses to solve the problem of energy consumption increase caused by the need of consuming a large amount of ton electric consumption to raise the temperature of the furnace charge when the industrial silicon enters the electric furnace, and provides an energy -conserving smelting system of industrial silicon, which can reduce the ton electric consumption of the industrial silicon electric furnace and achieve the effect of saving production cost.
[0004] The utility model discloses a technical scheme that is:
[0005] An energy -conserving smelting system of industrial silicon is provided, which comprises:
[0006] The mixing chamber has a first inlet and a first outlet, and is used for mixing furnace charge. The rotary kiln has a second inlet and a second outlet, and a soft rubber belt is arranged between the second inlet and the first outlet of the mixing chamber for conveying mixed furnace charge. The discharge chamber is located at the second outlet, and a hopper is arranged in the discharge chamber. The hopper corresponds to the second outlet and is used for loading mixed furnace charge. The top charging system has a third inlet and a third outlet, and is used for containing mixed furnace charge. The conveying device is located between the second outlet and the third inlet, and is used for conveying the hopper. The electric furnace is connected with the third outlet, and is used for heating and smelting mixed furnace charge.
[0007] Optionally, the material tank comprises a tank body, a connecting rod, a base and a pull hook, the top of the tank body is provided with a fourth feeding port, and the bottom of the tank body is provided with a fourth discharging port; the base has an isosceles trapezoidal cross section, the base is located at the fourth discharging port of the material tank, the small-diameter end of the base faces the interior of the material tank, and the large-diameter end of the base has a size larger than the diameter of the fourth discharging port; the connecting rod is located in the interior of the material tank and is vertically arranged at the top end of the base; the pull hook is arranged at the top end of the connecting rod; when the connecting rod moves upwards along the central axis of the material tank, the base seals the discharging port of the material tank.
[0008] Optionally, the discharging chamber comprises a plurality of baffles, each of the baffles is sequentially connected with the adjacent baffles in a head-to-tail mode to form a hollow column; one of the baffles is provided with a sampling hole, and a switch door covering the sampling hole is rotatably connected to the baffle.
[0009] Optionally, the conveying device is a travelling crane.
[0010] Optionally, the furnace top feeding system comprises a feeding bin and a discharging pipe, the third feeding port of the feeding bin is used for feeding the mixed furnace charge in the material tank, the discharging pipe is in communication with the feeding bin through the third discharging port, and the other end of the discharging pipe is in communication with the electric arc furnace.
[0011] Optionally, the rotary kiln is provided with an air inlet end, the electric arc furnace is provided with an air outlet end, a communication pipe is in communication between the air outlet end and the air inlet end, and an air pump is arranged on the communication pipe.
[0012] Optionally, the inner walls of the material tank, the feeding bin and the discharging pipe are sequentially provided with a high-temperature-resistant layer and a corrosion-resistant layer from the outside to the inside.
[0013] The beneficial effects of the present application are as follows:
[0014] The rotary kiln is arranged between the mixing chamber and the electric arc furnace, so that the mixed furnace charge entering the electric arc furnace from the mixing chamber can be preheated when passing through the rotary kiln. The mixed furnace charge is discharged from the first discharging port of the mixing chamber, enters the second feeding port through the connected soft rubber belt, and then enters the rotary kiln. The rotary kiln heats the mixed furnace charge, so that the temperature of the mixed furnace charge is increased from room temperature to 1000 DEG C. Then, the mixed furnace charge discharged from the second discharging port of the rotary kiln is high-temperature calcined sand. The discharged high-temperature calcined sand is filled into the material tank in the discharging chamber for transportation. After the material tank is filled, the material tank is conveyed to the third feeding port of the furnace top feeding system by the conveying device. The material tank is opened, and the high-temperature calcined sand filled in the tank enters the electric arc furnace through the third feeding port. At this time, the reduction smelting temperature difference of the mixed furnace charge, that is, the high-temperature calcined sand, in the electric arc furnace is reduced, and only needs to be increased from 1000 DEG C to about 1700 DEG C, so that the ton electricity consumption of the electric arc furnace is greatly reduced, and the energy consumption is reduced. BRIEF DESCRIPTION OF DRAWINGS
[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the accompanying drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced. Obviously, the accompanying drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.
[0016] Figure 1 A process schematic diagram of the energy-saving smelting system;
[0017] Figure 2 A structural schematic diagram of the discharge chamber;
[0018] Figure 3 A structural schematic diagram of the material tank.
[0019] The drawings show that: 1 - baffle, 2 - sampling hole, 3 - switch door, 4 - material tank, 40 - connecting rod, 41 - base, 42 - draw hook. DETAILED DESCRIPTION
[0020] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.
[0021] The following disclosure provides many different embodiments or examples for implementing different structures of the present application. In order to simplify the disclosure of the present application, the components and settings of specific examples are described in the following. Of course, they are only examples, and the purpose is not to limit the present application.
[0022] The embodiments of the present application will be described in detail below with reference to the accompanying drawings.
[0023] EMBODIMENT
[0024] As shown in the drawings, the present embodiment provides an energy-saving smelting system for industrial silicon, comprising: Figures 1-3
[0025] A mixing chamber, the mixing chamber has a first inlet and a first outlet, and the mixing chamber is used for mixing furnace charge;
[0026] The rotary kiln has a second feeding port and a second discharging port, and a soft rubber belt is arranged between the second feeding port and the first discharging port of the mixing chamber to convey the mixed furnace charge.
[0027] The discharging chamber is located at the second discharging port, and the inside of the discharging chamber is provided with a material tank 4 corresponding to the second discharging port for loading the mixed furnace charge.
[0028] The furnace top charging system has a third feeding port and a third discharging port, and is used for loading the mixed furnace charge.
[0029] The conveying device is arranged at the second discharging port and the third feeding port to convey the material tank 4.
[0030] The electric arc furnace is connected to the third discharging port and is used for heating and smelting the mixed furnace charge.
[0031] In the mixing chamber, the silica washed with medicinal water in advance is used as the smelting raw material, which is fed into the mixing chamber through the first feeding port, and the washed fine coal is used as the reducing agent, and wood blocks and charcoal are added according to the composition of the product and the furnace condition for mixing. The mixed raw material is conveyed through the soft rubber belt connected between the first discharging port and the second feeding port and directly enters the rotary kiln. The mixed raw material entering the rotary kiln can raise the temperature to 1000℃ to form calcined sand, achieving the effect of preheating treatment. During the continuous operation of the rotary kiln, the calcined sand is discharged from the second discharging port of the rotary kiln and enters the discharging chamber at a position corresponding to the second feeding port. The inside of the discharging chamber is provided with a material tank 4 for loading the calcined sand. The conveying device is generally arranged at the top beam of the factory building. If the overall smelting system is in an open environment and there is no similar factory building structure to support the arrangement, a supporting rod can be arranged to support the conveying device to achieve the effect of conveying the material tank 4. The furnace top charging system is used for temporary storage of the calcined sand, the material tank 4 loaded with the calcined sand is conveyed to the furnace top charging system by the conveying device, and then the calcined sand in the material tank 4 is transferred to the furnace top charging system for temporary storage, and then sent to the electric arc furnace for calcined sand temperature reduction treatment.
[0032] In the embodiment, compared with the existing industrial silicon smelting system, a rotary kiln, a tank 4 and a conveying device are added, and the feeding belt for conveying the mixed raw materials in the traditional smelting system is removed. In order to match the practicality of the ore smelting furnace, the 33MVA ore smelting furnace is selected in the embodiment, and the length of the rotary kiln matched therewith is 100-110m, and the diameter is about 4.8m, and the calcined ore production is adjusted according to the speed, fuel quantity and production demand. According to the thermodynamic calculation, in order to raise the furnace charge from normal temperature to 1000℃, each mole of silica needs to absorb 83Kcal of heat, and the 33MVA ore smelting furnace consumes about 45t of silica, 30t of reducing agent and 15t of loose agent in 8 hours, absorbs about 6225 million Kcal of heat, and the moisture in the reducing agent and wood block is about 10t, which needs to absorb 824 million Kcal of heat to heat the water from normal temperature to 700℃, and the energy absorbed by the two endothermic reactions is equivalent to 82000Kwh of electricity, and the electricity cost is 41000 yuan according to the electricity unit price of 0.5 yuan. If the rotary kiln is used to raise the silica and reducing agent to 1000℃, 11.6t of power coal is needed to provide heat, and the cost of 11.6t of power coal is 7540 yuan according to the unit price of 650 yuan per ton, which saves 33460 yuan of electricity cost. Therefore, 100380 yuan of electricity cost can be saved in 24 hours.
[0033] The 33MVA industrial silicon ore smelting furnace needs to consume about 215t of furnace charge per day, and the four industrial silicon ore smelting furnaces consume 860t of furnace charge per day. One φ4.8x110m rotary kiln can meet the material quantity of four 33MVA industrial silicon ore smelting furnaces, and four 33MVA industrial silicon ore smelting furnaces can save 400,000 yuan of electricity cost per day. In 330 days of production time per year, 1320 million yuan of electricity cost can be saved, which is equivalent to the cost of the rotary kiln and the cost of the tank 4 and the crane.
[0034] In one of the embodiments, the tank 4 includes a tank body, a connecting rod 40, a base 41 and a pull hook, the tank body has a fourth feeding port at the top and a fourth discharging port at the bottom; the base 41 is in the shape of an isosceles trapezoid in cross section, the base 41 is located at the fourth discharging port of the tank 4, the small-diameter end of the base 41 faces the inside of the tank 4, and the large-diameter end of the base 41 is larger in size than the diameter of the fourth discharging port; the connecting rod 40 is located inside the tank 4, and the bottom end is vertically arranged at the top end of the base 41; and the pull hook is arranged at the top end of the connecting rod 40.
[0035] When the connecting rod 40 moves upward along the central axis of the tank 4, the base 41 closes the discharging port of the tank 4.
[0036] In use, as Figure 3As shown, the furnace charge is filled into the ladle 4 through the fourth inlet of the ladle 4, at this time, the fourth outlet of the ladle 4 is blocked by the base 41, and the furnace charge cannot leak out from the gap between the base 41 and the fourth outlet of the ladle 4. When the filling of the furnace charge in the ladle 4 is completed, the connecting rod 40 is lifted by the cooperation with the draw hook for transportation, and in this process, the base 41 at the bottom of the connecting rod 40 always seals the fourth outlet of the ladle 4 to prevent the leakage of the ladle 4 during transportation. When the ladle 4 is transported to the third inlet of the furnace top charging system by the transportation device, the transportation device is lowered to place the ladle 4 on the third inlet, and the ladle 4 is clamped at the third inlet. At this time, the transportation device continues to be lowered, and because the ladle 4 is filled with furnace charge, the base 41 is subjected to the gravity of the furnace charge in the ladle 4, and the transportation device continues to be lowered without applying upward tension to the base 41 through the connecting rod 40, so that the base 41 is separated from the fourth outlet of the ladle 4, and the furnace charge in the ladle 4 leaks out from the gap between the base 41 and the fourth outlet, completing the transportation and addition of the furnace charge. It is worth noting that because the temperature of the furnace charge is high, in order to avoid the influence of high-temperature furnace charge on the use of the connecting rod 40 and the base 41, heat-resistant steel with the material 1Cr25Ni20 is selected for use.
[0037] In one embodiment, as shown in Figure 2 The discharge chamber is composed of a plurality of baffles 1, each of which is sequentially connected end to end to form a hollow cylinder. One of the baffles 1 is provided with a sampling hole 2, and the baffle 1 is rotatably connected with a switch door 3 covering the sampling hole 2.
[0038] The discharge chamber is composed of a plurality of baffles 1, each of which is sequentially connected end to end to form a hollow cylinder. One of the baffles 1 is provided with a sampling hole 2, and the baffle 1 is rotatably connected with a switch door 3 covering the sampling hole 2.
[0039] In one embodiment, the transportation device is a crane.
[0040] In this embodiment, the transportation device is a crane, and the crane is a bridge crane. The bridge crane can vertically lift or horizontally move the weight hung on the hook or other material taking device. The crane is set according to the actual situation on site, and is generally hung on the inner top of the factory building, so as to facilitate the transportation of the ladle 4 filled with preheated materials in the rotary kiln to the furnace top charging system.
[0041] In one of the embodiments, the furnace top charging system comprises a charging bin and a discharging pipe, the third feeding port of the charging bin is used for feeding the mixed furnace charge in the tank 4, the discharging pipe is communicated with the charging bin through the third discharging port, and the other end of the discharging pipe is communicated with the electric furnace.
[0042] In the smelting system of industrial silicon, the furnace top charging system comprises a charging bin and a discharging pipe, the charging bin is mainly composed of a bin body, an inner chute and a group of (upper and lower) level meters, and is used for containing raw materials such as ores and cokes mixed uniformly in a certain proportion. In this embodiment, the raw material is high-temperature calcined sand after preheating treatment by a rotary kiln, which is then charged into the electric furnace through the connected discharging pipe.
[0043] In use, the transport device transports the tank 4 filled with high-temperature calcined sand in the discharging chamber to the upper feeding port of the furnace top charging system, then controls the transport device to move the tank 4 towards the third feeding port of the furnace top charging system, and after the tank 4 approaches the third feeding port, the high-temperature calcined sand in the tank 4 is transferred to the charging bin in the furnace top charging system for storage, until the electric furnace needs to be charged, the calcined sand in the charging bin is then charged into the electric furnace through the discharging pipe.
[0044] In one of the embodiments, as shown in Figure 1 The rotary kiln is provided with an air inlet end, the electric furnace is provided with an air outlet end, a communication pipe is connected between the air outlet end and the air inlet end, and an air pump is arranged on the communication pipe.
[0045] The communication pipe is connected between the air outlet end arranged on the rotary kiln and the air inlet end arranged on the electric furnace, so that the heat generated during the operation of the rotary kiln is transmitted to the electric furnace at the other end through the communication pipe, thereby achieving the effect of collecting waste heat, realizing waste heat power generation, and reducing the power consumption cost.
[0046] In one of the embodiments, the inner walls of the tank 4, the charging bin and the discharging pipe are sequentially provided with a high-temperature resistant layer and a corrosion resistant layer from outside to inside.
[0047] In this embodiment, the high-temperature resistant layer is specifically an aluminum oxide coating or a zirconium oxide coating, and the two kinds of coatings have excellent high-temperature resistance and heat insulation performance, and are suitable for the high-temperature environment of the tank 4, the charging bin and the discharging pipe in the smelting system. The corrosion resistant layer is specifically a KNM17 ceramic coating, a KNM60 alloy coating, a KNM22 polyurethane elastomer, a KNM17 epoxy resin coating, etc., and such coating materials have excellent corrosion resistance and wear resistance, and are suitable for the working environment in contact with high-temperature calcined sand.
[0048] Finally, it should be noted that the above is only the preferred embodiment of the present application, and is not intended to limit the present application, for those skilled in the art, the present application can have various changes and variations, in the case of no conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims
1. An energy efficient smelting system of industrial silicon, characterized by, The application relates to a mineral heat furnace system, which comprises the following parts: a mixing chamber with a first feeding port and a first discharging port, which is used for mixing furnace materials; a rotary kiln with a second feeding port and a second discharging port, wherein a soft rubber belt is arranged between the second feeding port and the first discharging port of the mixing chamber and used for conveying the mixed furnace materials; a discharging chamber arranged at the second discharging port, wherein an inner part of the discharging chamber is provided with a material tank corresponding to the second discharging port and used for loading the mixed furnace materials; a furnace top feeding system with a third feeding port and a third discharging port, which is used for loading the mixed furnace materials; a conveying device arranged at the second discharging port and the third feeding port and used for conveying the material tank; and a mineral heat furnace connected with the third discharging port and used for heating and smelting the mixed furnace materials.
2. The energy efficient smelting system of metallurgical grade silicon as claimed in claim 1 wherein, The material tank comprises a tank body, a connecting rod, a base and a pull hook, the top of the tank body is provided with a fourth feeding port, the bottom of the tank body is provided with a fourth discharging port; the base is in the shape of an isosceles trapezoid, the base is arranged at the fourth discharging port of the material tank, the small-diameter end of the base faces the inner part of the material tank, and the large-diameter end of the base is larger than the diameter of the fourth discharging port; the connecting rod is arranged in the inner part of the material tank and vertically arranged at the top end of the base; the pull hook is arranged at the top end of the connecting rod; when the connecting rod moves upwards along the central axis of the material tank, the base seals the discharging port of the material tank.
3. The energy efficient smelting system of metallurgical grade silicon as claimed in claim 2, wherein, The discharging chamber comprises a plurality of baffles, the baffles are sequentially connected in a head-to-tail mode to form a hollow column, one of the baffles is provided with a sampling hole, and a switch door covering the sampling hole is rotatably arranged on the baffle.
4. The energy efficient smelting system of metallurgical grade silicon as claimed in claim 3, wherein, The conveying device is a travelling crane.
5. The energy efficient smelting system of metallurgical grade silicon as claimed in claim 4, wherein, The furnace top feeding system comprises a feeding bin and a discharging pipe, the third feeding port of the feeding bin is used for feeding the mixed furnace materials in the material tank, the discharging pipe is communicated with the feeding bin through the third discharging port, and the other end of the discharging pipe is communicated with the mineral heat furnace.
6. The energy efficient smelting system of silicon for industrial use as claimed in claim 1 or 5 wherein, The rotary kiln is provided with an air inlet end, the mineral heat furnace is provided with an air outlet end, a communication pipe is arranged between the air outlet end and the air inlet end, and an air pump is arranged on the communication pipe.
7. The energy efficient smelting system of metallurgical grade silicon as claimed in claim 5 wherein, A high-temperature-resistant layer and a corrosion-resistant layer are sequentially arranged on the inner walls of the material tank, the feeding bin and the discharging pipe from the outside to the inside.