A paste temperature control system and method for prebaked anode production

Abstract

The present application relates to a kind of paste temperature control system and method for prebaked anode production, control system includes unloading mechanism, unloading mechanism is set to the bottom opening of paste mixing kettle, unloading mechanism includes arc-shaped unloading door, both sides of unloading door are connected with side plate, side plate is rotationally arranged on main shaft, and is connected with hydraulic cylinder, the side plate is circular plate, side plate is connected with arc-shaped cover plate along the opposite end of unloading door, arc-shaped cover plate is consistent with the width of unloading door, arc-shaped cover plate and unloading door are left and set up upper opening and lower opening, upper opening is used to butt joint with the bottom opening of mixing kettle, lower opening is located in the opposite side of upper opening along main shaft;Two side plates are connected with motor-driven cutter shaft, and stirring blade is arranged on cutter shaft;Cutter shaft has two, and is located in the two sides close to lower opening;The present application can be reformed to original intermittent mixing kettle paste production system, improve paste cooling efficiency, and can keep paste fluidity.In addition, the present application is difficult to implement.

Description

Technical Field

[0001] This invention belongs to the field of prebaked anode production technology, specifically relating to a temperature control system and method for prebaked anode production paste. Background Technology

[0002] Paste mixing and molding are crucial steps in prebaked anode production, and paste temperature control significantly impacts the molding yield. If the paste temperature is too high, the bonding strength is insufficient, leading to cracks after demolding; if the temperature is too low, the plasticity is insufficient, resulting in low bulk density and poor appearance after molding. Furthermore, since the paste is typically vibrated and molded using a vibratory molding machine, it needs to maintain good fluidity to facilitate movement within the feed hopper during vibration molding.

[0003] Some domestic prebaked anode manufacturers use the German Erich high-powered kneader, such as the carbon plant of Chinalco Guizhou Branch. This high-powered kneader has a strong cooling function; after wet mixing, the paste is cooled by water spray under high-speed stirring with agitators, ensuring the paste reaches the required temperature. Other manufacturers use kneading pans. After wet mixing, the paste is unloaded from the pan onto a slatted conveyor or belt conveyor, where it cools naturally during transport. Cooling time is controlled by adjusting the unloading and conveying speeds, resulting in low cooling efficiency. Furthermore, cooling the paste in a piled state leads to rapid surface cooling and slow internal cooling, resulting in poor temperature uniformity. Although a homogenizer is installed during the feeding stage to improve uniformity, its mixing effect is limited and cannot completely solve the problem of uneven paste temperature.

[0004] When using a kneading pan to produce paste, the wet mixing temperature is difficult to increase due to the limited cooling efficiency of the paste, generally remaining around 160℃, which is detrimental to improving paste quality. However, manufacturers using Eris high-powered kneading machines can control the wet mixing temperature above 180℃, resulting in better paste quality. Furthermore, when improved paste cooling is required, extending the cooling time by reducing unloading and conveying speeds will significantly impact production efficiency.

[0005] Several paste cooling solutions are disclosed in the prior art, which can be combined with kneading pot production systems to improve the paste cooling effect. For example, patent CN102152947A discloses a screw paste conveyor that uses a screw conveyor with a water-cooled jacket to transport paste, which can indirectly cool the paste using circulating cooling water. However, because the screw conveyor generates axial extrusion force when transporting materials, the paste is prone to agglomeration during the transport process, which is not conducive to maintaining the fluidity of the paste and can also cause blockage problems.

[0006] The anode paste cooling device proposed in patent CN2589489Y uses a rotating drum to spray atomized cooling water into the paste entering the drum for cooling. However, because the paste has a certain viscosity, the paste particles tend to clump together when they collide and are squeezed together during the tumbling process in the drum, which is not conducive to maintaining the fluidity of the paste.

[0007] Moreover, when modifying the existing production system, site limitations and modification costs need to be considered. Adding a cooling device not only incurs high investment costs but is also difficult to implement. Summary of the Invention

[0008] To address the aforementioned technical problems, the present invention first provides a temperature control system for prebaked anode production paste, the specific solution of which is as follows:

[0009] A temperature control system for prebaked anode production paste includes a discharge mechanism located at the bottom opening of a paste mixing pot. The discharge mechanism includes an arc-shaped discharge gate with side plates connected to both sides. The side plates are rotatably mounted on a main shaft and connected to hydraulic cylinders. The side plates are circular, and an arc-shaped cover plate is connected to one end of the side plate opposite to the discharge gate. The arc-shaped cover plate has the same width as the discharge gate. An upper opening and a lower opening are provided between the arc-shaped cover plate and the discharge gate. The upper opening is used to align with the bottom opening of the mixing pot, and the lower opening is located on the opposite side of the upper opening along the main shaft. A motor-driven cutter shaft is connected between the two side plates, and a stirring blade is provided on the cutter shaft. There are two cutter shafts, located on both sides near the lower opening.

[0010] It also includes atomizing nozzles and air inlets. There are two atomizing nozzles, located on the lower sides of the unloading mechanism. The atomizing nozzles are tilted inwards and face the bottom opening of the paste mixing pot. The air inlets are located on the side plate and are connected to the exhaust pipe.

[0011] Furthermore, the cutter shaft is located radially at the end of the lower opening of the side plate.

[0012] Furthermore, it also includes a conveying mechanism, which is a belt conveyor. The belt conveyor is equipped with an insulation cover. The insulation cover has a feeding port along the inlet end and a discharging port along the outlet end. The feeding port is used to connect with the lower opening of the unloading mechanism. The atomizing nozzle is fixed to the inner wall of the insulation cover below the feeding port.

[0013] Furthermore, the insulation cover has a sandwich layer, the exhaust pipe is connected to the sandwich layer and connected to the feed end, and the insulation cover has an exhaust pipe along the discharge end, and the exhaust pipe is equipped with an exhaust fan.

[0014] Furthermore, the belt conveyor is provided with a front uniform feeder and a rear uniform feeder in sequence along the conveying direction. The front uniform feeder is provided with a first temperature detection point, which is used to control the spray volume of the atomizing nozzle.

[0015] Furthermore, it also includes a feeding mechanism, which includes a rectangular hopper. The upper part of the rectangular hopper is provided with a horizontal material-equalizing spiral, and the material-equalizing spiral has two sections of opposite spirals. The bottom of the rectangular hopper is provided with a vibrating feeder. The side wall of the rectangular hopper is provided with a second temperature detection point, which is located near the middle of the material-equalizing spiral. The rear material-equalizing frame is provided with an air inlet, which is connected to a blower. The second temperature detection point is used to control the air volume of the blower.

[0016] Furthermore, a material leveling plate is connected to the lower part of the rear material leveling rack. The material leveling plate has a triangular cross-section, with the corners of the material leveling plate facing the feeding direction, and the air vent is located on the back of the material leveling plate.

[0017] This invention also provides a method for controlling the temperature of prebaked anode production paste, which uses the prebaked anode production paste temperature control system of this invention and includes the following steps:

[0018] 1) After the paste is kneaded, the unloading mechanism is started, the unloading gate is rotated to the position, the upper opening is connected with the bottom opening of the kneading pot, the mixing pot agitator is reversed to unload, and at the same time the atomizing nozzle and the cutter shaft are started to spray and cool the paste. The spray volume is controlled according to the temperature of the first temperature detection point.

[0019] 2) Start the induced draft fan. The hot flue gas generated by the unloading mechanism enters the heat insulation cover of the conveying mechanism through the exhaust pipe to keep the paste conveyed by the belt conveyor warm.

[0020] 3) Start the feeding mechanism's equalizing screw, the feeding mechanism receives the material, and the blower's air volume is controlled according to the temperature at the second temperature detection point.

[0021] Furthermore, the temperature at the first temperature detection point is controlled at 145-150℃.

[0022] Furthermore, the temperature at the second temperature detection point is controlled at 140-145℃.

[0023] The advantages of this invention are that it can modify the existing intermittent mixing pot paste production system, improve paste cooling efficiency, and maintain paste fluidity, which is beneficial for improving paste quality, reducing molding cracks, and increasing the green body qualification rate. Furthermore, this invention has low implementation costs, is less restricted by site conditions, and is relatively easy to implement. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the unloading mechanism and conveying mechanism in this invention.

[0025] Figure 2 This is a cross-sectional schematic diagram of the unloading mechanism in this invention.

[0026] Figure 3 This is a schematic diagram of the feeding mechanism in this invention.

[0027] Figure 4 This is a cross-sectional schematic diagram of the homogenizing plate in this invention. Detailed Implementation

[0028] The present invention will now be clearly described in conjunction with specific embodiments. This description is merely illustrative and is not intended to limit the scope of the invention. Any modifications, equivalent substitutions, or improvements made by those skilled in the art based on the embodiments of the present invention without inventive effort to obtain all other embodiments should be included within the scope of protection of the present invention.

[0029] Example

[0030] Example 1

[0031] like Figures 1-4 A temperature control system for prebaked anode production paste includes a discharge mechanism located at the bottom opening of the paste mixing pot 1. The discharge mechanism includes an arc-shaped discharge gate 2, with side plates 3 connected to both sides of the discharge gate. The side plates are rotatably mounted on a main shaft and connected to hydraulic cylinders. The side plates are circular plates, and an arc-shaped cover plate 4 is connected to one end of the side plate opposite to the discharge gate. The arc-shaped cover plate has the same width as the discharge gate. An upper opening 5 and a lower opening 6 are provided between the arc-shaped cover plate and the discharge gate. The upper opening is used to connect with the bottom opening of the mixing pot, and the lower opening is located on the opposite side of the upper opening along the main shaft. A motor-driven cutter shaft 7 is connected between the two side plates, and a stirring blade 8 is provided on the cutter shaft. There are two cutter shafts, located on both sides near the lower opening.

[0032] It also includes atomizing nozzles 9 and air inlets 10. Two atomizing nozzles are provided, located on either side below the unloading mechanism, and are inclined inwards towards the bottom opening of the paste mixing pot. The air inlets are located on the side plate and are connected to exhaust pipes 13. To prevent paste from entering the exhaust pipe along the air inlets, a filter screen is installed at the air inlets. The exhaust pipe is a flexible corrugated pipe, which does not affect the rotation of the unloading gate.

[0033] This invention is an improvement on the existing unloading structure, requiring minimal on-site modifications and is easy to implement. The original unloading mechanism consists of an arc-shaped unloading gate at the bottom opening of the mixing pot, with fan-shaped side plates connected to both sides of the gate. A hydraulic cylinder drives the unloading gate to rotate, thus opening and closing the bottom opening of the mixing pot.

[0034] This invention replaces the original fan-shaped side plate with a circular side plate, and installs an arc-shaped cover plate on the side opposite the original unloading gate. The arc-shaped cover plate, the circular side plate, and the unloading gate together form a relatively enclosed cylindrical space, which serves as the space for atomizing and cooling the paste. Simultaneously, a cutter shaft is added, using a high-speed rotating agitator to disperse the falling paste and achieve a mixing effect, improving the uniformity of the atomization cooling zone and thus enhancing the temperature consistency of the cooled paste.

[0035] In addition, the present invention performs spray cooling during the natural falling process of the paste, which can avoid the paste from piling up and affecting the full contact with the cooling water mist, and can also avoid squeezing the paste and reducing its fluidity.

[0036] Before the implementation of this invention, the inventors attempted to spray and cool the paste by directly setting an atomizing nozzle below the bottom opening. However, the mixing effect between the cooling water mist and the paste was poor. When the spray volume was small, the cooling effect was poor. When the spray volume was large, there was a lot of residual moisture in the paste, which affected the adhesion of the paste.

[0037] After implementing this invention, a relatively small amount of spray can achieve a good cooling effect, the wet mixing temperature in the mixing pot can be increased to about 170℃, and the paste temperature can be controlled at about 140℃. After the cooling water mist comes into full contact with the high-temperature paste, it evaporates into water vapor, resulting in less residual moisture in the paste.

[0038] In this invention, the cutter shaft plays a mixing role in the paste during spray cooling, and its arrangement has a key impact on the implementation of this invention. In some experimental examples, the cutter shaft is positioned near the opening of the unloading mechanism, which causes material blockage when the cutter shaft is started, affecting the normal unloading of the mixing pot; or the cutter shaft is positioned in the middle of the unloading mechanism, which can solve the material blockage problem, but may cause blockage of the air vents on the side plate.

[0039] With the cutter shaft positioned near the lower opening and the air inlet positioned near the upper opening on the side plate, the mixing pot can discharge material normally, and the mixing area is located below the discharge mechanism, with no blockage at the air inlet on the side plate.

[0040] Specifically, in this embodiment, the cutter shaft is located at the radial position of the end of the lower opening of the side plate.

[0041] In addition, the way the atomizing nozzle is set also has a great impact on the cooling effect.

[0042] In other test cases, the atomizing nozzles were placed on the unloading gate and the inner wall of the arc-shaped cover plate of the unloading mechanism. This resulted in two problems: firstly, it was prone to clogging; secondly, the contact time with the paste was short, resulting in poor cooling effect.

[0043] The present invention also includes a conveying mechanism, which adopts the original belt conveyor 11, and adds a heat insulation cover 12 to the outside of the belt conveyor. The heat insulation cover has a feeding port along the feeding end and a discharging port along the discharging end. The feeding port is used to connect with the lower opening of the unloading mechanism. The atomizing nozzle is specifically fixed on the inner side wall of the heat insulation cover below the feeding port.

[0044] By setting it in the heat insulation cover, it not only provides a certain heat preservation effect, but also forms a relatively sealed system with the unloading mechanism. With the negative pressure of the exhaust pipe, the atomizing nozzle sprays cooling water mist below the unloading mechanism. Under the action of negative pressure, it flows upward and forms a counterflow with the naturally falling paste, prolonging the contact time between the water mist and the paste, which helps to improve the mixing effect of the water mist and the paste and improve the cooling effect.

[0045] Based on the existing insulation cover on the outside of the belt conveyor, this embodiment also provides an improvement: the insulation cover is configured as a sandwich structure, with the exhaust pipe 13 connected to the sandwich and attached to the feed end. An exhaust fan is installed along the discharge end of the insulation cover. The high-temperature flue gas generated by the unloading mechanism passes through the insulation cover sandwich along the exhaust pipe, which improves the insulation effect of the insulation cover and prevents uneven cooling of the paste conveyed by the belt conveyor.

[0046] In this embodiment, a front uniform feeder 14 and a rear uniform feeder 15 are sequentially arranged on the belt surface of the belt conveyor along the conveying direction. The front uniform feeder is provided with a first temperature detection point 16, which is used to control the spray volume of the atomizing nozzle.

[0047] The invention also includes a feeding mechanism comprising a rectangular hopper 17, with a transverse material-equalizing spiral at the top and two counter-rotating spiral sections on the spiral; a vibrating feeder 18 at the bottom of the rectangular hopper; a second temperature detection point 19 located near the middle of the material-equalizing spiral on the side wall of the rectangular hopper; and an air inlet 20 connected to a blower 21 on the rear material-equalizing frame 15. The second temperature detection point is used to control the airflow of the blower. By adding an air-cooling mechanism to the belt conveyor, the accuracy of paste temperature control is improved. The purpose of adding air cooling is to provide auxiliary cooling; in actual production, a smaller airflow is used. Furthermore, changing the original vertical spiral to a transverse arrangement and using a vibrating feeder reduces the compression of the paste during feeding, which helps maintain the fluidity of the paste.

[0048] Specifically, a uniform material distribution plate 22 is connected to the lower part of the rear uniform material distribution frame. The plate has a triangular cross-section, with the corners facing the feeding direction. The air vent 20 is located on the back of the plate. This arrangement facilitates uniform cooling of the paste and prevents the air vent from becoming clogged. The paste flows separately along both sides of the plate and converges on the back of the plate, allowing the air vent to also cool the lower layer of paste.

[0049] The system of the present invention is implemented according to the following steps when producing paste:

[0050] 1) After the paste is kneaded, the unloading mechanism is started, the unloading gate rotates to the position, the upper opening connects with the bottom opening of the kneading pot, the mixing pot agitator reverses to unload, and at the same time the atomizing nozzle and the cutter shaft are started to spray and cool the paste. The spray volume is controlled according to the temperature of the first temperature detection point; specifically, the temperature of the first temperature detection point is controlled at 145-150℃.

[0051] 2) Start the induced draft fan. The hot flue gas generated by the unloading mechanism enters the heat insulation cover of the conveying mechanism through the exhaust pipe to keep the paste conveyed by the belt conveyor warm.

[0052] 3) Start the feeding mechanism's equalizing screw, and the feeding mechanism receives the material. Control the blower's airflow based on the temperature at the second temperature detection point. Specifically, the temperature at the second temperature detection point is controlled between 140-145℃.

Claims

1. A method for controlling the temperature of paste produced in the production of prebaked anodes, characterized in that, The temperature control system for prebaked anode production paste includes a discharge mechanism located at the bottom opening of the paste mixing pot. The discharge mechanism includes an arc-shaped discharge gate with side plates connected to both sides. The side plates are rotatably mounted on a main shaft and connected to hydraulic cylinders. Each side plate is circular, and an arc-shaped cover plate is connected to the side plate opposite the discharge gate. The arc-shaped cover plate has the same width as the discharge gate. An upper opening and a lower opening are provided between the arc-shaped cover plate and the discharge gate. The upper opening aligns with the bottom opening of the mixing pot, and the lower opening is located on the opposite side of the upper opening along the main shaft. A motor-driven cutter shaft is connected between the two side plates, and two agitators are mounted on the cutter shaft. The cutter shaft has two shafts, located on either side near the lower opening. It also includes atomizing nozzles and air inlets. There are two atomizing nozzles, located on the lower sides of the unloading mechanism. The atomizing nozzles are tilted inwards and face the bottom opening of the paste mixing pot. The air inlets are located on the side plate and are connected to the exhaust pipe. It also includes a conveying mechanism, which is a belt conveyor. The belt conveyor is equipped with an insulation cover. The insulation cover has a feeding port along the feeding end and a discharging port along the discharging end. The feeding port is used to connect with the lower opening of the unloading mechanism. The atomizing nozzle is fixed to the inner wall of the insulation cover below the feeding port. The insulation cover has a double layer, the exhaust pipe is connected to the double layer and connected to the feed end, and the insulation cover has an exhaust pipe along the discharge end, and the exhaust pipe is equipped with an exhaust fan. The belt conveyor has a front equalizer and a rear equalizer arranged sequentially along the conveying direction on the belt surface. The front equalizer is provided with a first temperature detection point, which is used to control the spray volume of the atomizing nozzle. It also includes a feeding mechanism, which includes a rectangular hopper. The upper part of the rectangular hopper is provided with a horizontal material equalization spiral, and the material equalization spiral has two sections of opposite spirals. The bottom of the rectangular hopper is provided with a vibrating feeder. The side wall of the rectangular hopper is provided with a second temperature detection point, which is located near the middle of the material equalization spiral. The rear material equalization frame is provided with an air outlet, which is connected to a blower. The second temperature detection point is used to control the air volume of the blower. And includes the following steps: 1) After the paste is kneaded, the unloading mechanism is started, the unloading gate is rotated to the position, the upper opening is connected with the bottom opening of the kneading pot, the mixing pot agitator is reversed to unload, and at the same time the atomizing nozzle and the cutter shaft are started to spray and cool the paste. The spray volume is controlled according to the temperature of the first temperature detection point. 2) Start the induced draft fan. The hot flue gas generated by the unloading mechanism enters the heat insulation cover of the conveying mechanism through the exhaust pipe to keep the paste conveyed by the belt conveyor warm. 3) Start the feeding mechanism's equalizing screw, the feeding mechanism receives the material, and control the blower's air volume according to the temperature at the second temperature detection point.

2. The method for controlling the temperature of prebaked anode production paste according to claim 1, characterized in that: The cutter shaft is located radially at the end of the lower opening of the side plate.

3. The method for controlling the temperature of prebaked anode production paste according to claim 1, characterized in that: The lower part of the rear material leveling rack is connected to a material leveling plate. The material leveling plate has a triangular cross-section, with the corners of the material leveling plate facing the feeding direction. The air vent is located on the back of the material leveling plate.

4. The method for controlling the temperature of prebaked anode production paste according to claim 1, characterized in that: The temperature at the first temperature detection point is controlled between 145-150℃.

5. The method for controlling the temperature of prebaked anode production paste according to claim 4, characterized in that: The temperature at the second temperature detection point is controlled at 140-145℃.

Images