Efficient pressurizing, mixing and kneading device for special carbon-graphite material

Abstract

The utility model relates to the technical field of carbon product production, and provides a special carbon-graphite material high-efficiency pressurization mixing and kneading device which comprises a mixing and kneading machine body, a heating layer, a mixing reamer and a liftable gland, and a mixing and kneading machine heat preservation layer is arranged on the outer side wall of the mixing and kneading machine body and the outer side wall of the heating layer. According to the asphalt mixing and kneading machine disclosed by the utility model, air in coke fine powder is reduced through the vacuum-pumping system, the flowing resistance of asphalt is reduced, the penetration of the asphalt in coke pores is enhanced, and the filling degree and the bonding strength of the asphalt are improved. The compactness of the paste is improved by strong mixing and kneading under the action of a gland, and heat generated by friction is beneficial to asphalt flowing and polycondensation reaction, so that the coking value is increased. The S-shaped reamers are different from conventional reamers, cross-linking of the paste is intensified through a unique movement mode, strong convection is achieved, kneading is intensified through extrusion force generated by the included angle between the reamers and the pot wall, and the paste is more uniform.

Description

Technical Field

[0001] This utility model relates to the field of carbon product manufacturing technology, and in particular to a high-efficiency pressure mixing device for special carbon graphite materials. Background Technology

[0002] The production process of specialty carbon graphite materials typically involves grinding coke particles into micron-sized fine powder using a grinding mill. The powder is then batched according to a specific formula. After batching, the fine powder is mixed and preheated, and then molten liquid asphalt is added and kneaded to form a paste. The kneaded paste is cooled to form blocks smaller than 10 cm in size. These blocks are then ground again into fine powder of tens of microns. The resulting green bodies are then formed through molding or isostatic pressing. After firing, the green bodies form specialty carbon materials. Further impregnation, secondary firing, and graphitization then produce specialty graphite materials. The finer the coke powder particles and the more pores they contain, the greater the amount of binder asphalt required, and the higher the final product performance.

[0003] The equipment used in the kneading process is a kneader, whose main function is to heat the fine coke powder to above 150℃, add molten liquid asphalt, or asphalt particles or powder, and knead. The asphalt, in its molten state, has excellent fluidity, allowing it to wet, penetrate, mix, and knead with the fine coke powder, thus forming a paste with a certain bonding strength. The kneading process is a crucial step in the production of special carbon and graphite materials; the quality of the kneader directly affects the quality of the paste, and consequently, the performance of the final carbon and graphite material products.

[0004] Traditional kneading machines, such as Figure 1 As shown, the mixing of special carbon graphite materials is usually carried out using a twin-shaft mixing mixer. The mixer is a closed type with asphalt pipes and flue gas pipes. It is used to add molten liquid asphalt for mixing. When coke fine powder is mixed with asphalt, a large amount of flue gas is generated, which is discharged through the flue gas pipes.

[0005] The kneading machine's reamer is a differential tangential reamer, with two separate reamers whose radii of motion are tangential, and the speed ratio is usually an odd number.

[0006] However, traditional kneading devices have many problems. Regarding the thoroughness of kneading, even if the kneader is enclosed, the fine coke powder inside will still come into contact with air. Because the fine coke powder has a highly porous structure, the air inside the pores hinders the penetration of asphalt into the pores, resulting in insufficient bonding strength between the asphalt and the fine coke powder, which adversely affects the product performance.

[0007] Regarding the uniformity of mixing, current methods for mixing coke powder and asphalt mainly rely on the squeezing and friction between the biaxial cutters and between the cutters and the pot wall. This makes the paste prone to suspending above the cutters, resulting in poor mixing and affecting overall uniformity. Furthermore, the tangential movement radii of the two cutters make it difficult for the paste to cross-link and move within the cutter's operating radius. Additionally, the cutter speed ratio is often odd, meaning the paste mainly moves within its own region during operation, further reducing the uniformity of mixing.

[0008] In terms of volatile matter control, the quality of paste kneading is directly reflected in the stability of the paste's volatile matter, which originates from asphalt. During the kneading process, asphalt undergoes cracking and condensation reactions due to high temperature and kneading action, releasing light components and reducing the volatile matter content of the paste. However, volatile matter is affected by factors such as temperature, asphalt dosage, and kneading time, making it difficult for conventional kneaders to actively control, resulting in unstable volatile matter control. Utility Model Content

[0009] The purpose of this invention is to provide a high-efficiency pressure mixing device for special carbon graphite materials. By using this device, the above-mentioned problems can be solved.

[0010] To solve the above-mentioned technical problems, this utility model provides the following technical solution: a high-efficiency pressure kneading device for special carbon graphite materials, including a kneader body and a heating layer, a mixing blade and a liftable pressure cap. The outer wall of the kneader body and the heating layer is provided with a kneader insulation layer. The top of the kneader body and the heating layer is provided with a pressure cap lifting hydraulic rod. The output end of the pressure cap lifting hydraulic rod is equipped with a liftable pressure cap. The mixing blades are installed on both sides inside the kneader body and the heating layer. A paste upper temperature measuring point is provided in the middle position inside the liftable pressure cap. A kneader discharge port is provided in the middle position at the bottom of the kneader body and the heating layer. A paste lower temperature measuring point is provided in the middle position inside the kneader discharge port.

[0011] Preferably, a coke fine powder feed pipe and valve and a liquid asphalt feed pipe and valve are provided on the right side of the kneader body and heating layer, with the coke fine powder feed pipe and valve located above the liquid asphalt feed pipe and valve. A flue gas pipe and valve and a vacuum pipe and valve are provided on the left side of the kneader body and heating layer, with the vacuum pipe and valve located above the flue gas pipe and valve.

[0012] Preferably, a heat transfer oil outlet valve and a heat transfer oil temperature measuring point are provided on the right side of the mixer body and heating layer. The heat transfer oil outlet valve is located below the liquid asphalt feed pipe and valve and above the heat transfer oil temperature measuring point. A heat transfer oil inlet valve is provided on the left side of the mixer body and heating layer. The heat transfer oil inlet valve is located below the flue gas pipe and valve. A heat transfer oil outlet valve is provided on the right side of the top of the liftable pressure cover, and a heat transfer oil inlet valve is provided on the left side of the top of the liftable pressure cover.

[0013] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0014] 1. This utility model provides a high-efficiency pressure kneading device for special carbon graphite materials. Through a vacuum system, it reduces air within the fine coke powder, lowers the flow resistance of asphalt, enhances its penetration into the pores of the coke, and improves the asphalt filling degree and bonding strength. The powerful kneading under the pressure of the cap increases the density of the paste, and the frictional heat generation facilitates asphalt flow and condensation reaction, increasing the coking value. The S-shaped reamer, unlike conventional devices, intensifies the cross-linking of the paste through a unique movement, achieving strong convection. The extrusion force generated by the angle between the reamer and the pot wall strengthens the kneading, making the paste more uniform.

[0015] 2. The present invention provides a high-efficiency pressure kneading device for special carbon graphite materials. The functions of vacuuming, pressure kneading, and flue gas extraction are independent of each other. Different combinations of functions can be flexibly selected according to actual needs. Solid or liquid asphalt can be added to meet diverse production requirements.

[0016] 3. This utility model provides a high-efficiency pressurized kneading device for special carbon graphite materials, which can be used for both hot mixing with heat transfer oil and cold mixing with a cooling medium. A coke fine powder preheating device can be installed at the front end to shorten the preheating time. Hot mixing and cold mixing functions can be switched within a single device, and a separate paste cooling device or a kneader using a cooling medium can be used at the rear end for cold mixing.

[0017] 4. This utility model provides a high-efficiency pressurized kneading device for special carbon graphite materials. The heating area of ​​the circulating heat transfer oil is far greater than that of electric heating, and the heating time is halved. With PLC control, temperature regulation is more convenient. Circulating refrigerant cooling allows refrigerant to flow through both the pot body and the pressure plate, resulting in a large heat exchange area. Combined with methods such as flue gas extraction, introduction of nitrogen or cold air, the cooling speed is accelerated.

[0018] 5. The present invention provides a high-efficiency pressure kneading device for special carbon graphite materials. During pressure kneading, the pressure cap and the paste generate heat, which can raise the kneading temperature to above 280°C. This allows the use of high softening point asphalt and compensates for the temperature limitations of conventional heat transfer oil.

[0019] 6. This utility model provides a high-efficiency pressure mixing device for special carbon graphite materials. Vacuuming improves the filling effect of asphalt on coke fine powder, pressure is applied by the cap to intensify mixing and kneading, and the S-shaped reamer promotes multiple cross-linking and separation of the paste. The combined effect shortens the mixing time.

[0020] 7. The present invention provides a high-efficiency pressure kneading device for special carbon graphite materials. By precisely controlling the extraction time and negative pressure through the extraction device, the volatile matter of the paste is effectively regulated, avoiding the problem of shrinkage during subsequent baking or defects in the quality of the molded product caused by abnormal volatile matter. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of a traditional kneading machine.

[0022] Figure 2 This is a front view of the cap of this utility model located in the lower limit area;

[0023] Figure 3 This is a front view of the pressure cap of this utility model located in the middle limiting area;

[0024] Figure 4 This is a front view structural diagram of the cap of this utility model located in the upper limit position area.

[0025] The following are the labels in the attached diagram: 1. Mixer body and heating layer; 2. Mixer insulation layer; 3. Mixer outlet; 4. Mixing cutter; 5. Liftable pressure cap; 6. Pressure cap lifting hydraulic rod; 7. Coke fine powder feed pipe and valve; 8. Liquid asphalt feed pipe and valve; 9. Flue gas pipe and valve; 10. Vacuum pipe and valve; 11. Mixer heat transfer oil inlet valve; 12. Mixer heat transfer oil outlet valve; 13. Pressure cap heat transfer oil inlet valve; 14. Pressure cap heat transfer oil outlet valve; 15. Lower temperature measuring point of paste; 16. Upper temperature measuring point of paste; 17. Mixer heat transfer oil temperature measuring point. Detailed Implementation

[0026] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0027] To further understand the content of this utility model, a detailed description of this utility model will be provided in conjunction with the accompanying drawings.

[0028] Combination Figures 2 to 4As shown, this utility model discloses a high-efficiency pressure kneading device for special carbon graphite materials, including a kneader body and heating layer 1, a mixing blade 4, and a liftable pressure cover 5. The outer wall of the kneader body and heating layer 1 is provided with a kneader insulation layer 2. The top of the kneader body and heating layer 1 is provided with a pressure cover lifting hydraulic rod 6. The bottom output end of the pressure cover lifting hydraulic rod 6 is equipped with a liftable pressure cover 5. The mixing blade 4 is installed on both sides inside the kneader body and heating layer 1. The middle position inside the liftable pressure cover 5 is provided with a paste upper temperature measuring point 16. The middle position at the bottom of the kneader body and heating layer 1 is provided with a kneader discharge port 3. The middle position inside the kneader discharge port 3 is provided with a paste lower temperature measuring point 15.

[0029] On the right side of the kneader body and heating layer 1, there are coke fine powder feed pipe and valve 7 and liquid asphalt feed pipe and valve 8. The coke fine powder feed pipe and valve 7 is located above the liquid asphalt feed pipe and valve 8. On the left side of the kneader body and heating layer 1, there are flue gas pipe and valve 9 and vacuum pipe and valve 10. The vacuum pipe and valve 10 is located above the flue gas pipe and valve 9.

[0030] The right side of the kneader body and heating layer 1 is provided with a kneader heat transfer oil outlet valve 12 and a kneader heat transfer oil temperature measuring point 17. The kneader heat transfer oil outlet valve 12 is located below the liquid asphalt feed pipe and valve 8 and above the kneader heat transfer oil temperature measuring point 17. The left side of the kneader body and heating layer 1 is provided with a kneader heat transfer oil inlet valve 11. The kneader heat transfer oil inlet valve 11 is located below the flue gas pipe and valve 9. The right side of the top of the liftable pressure cover 5 is provided with a pressure cover heat transfer oil outlet valve 14, and the left side of the top of the liftable pressure cover 5 is provided with a pressure cover heat transfer oil inlet valve 13.

[0031] Working principle:

[0032] The kneader uses heat transfer oil for heating. Opening the heat transfer oil inlet valve 11 and outlet valve 12 allows heat transfer oil to flow into the kneader, thus heating it. When coke powder is added to the kneader, the kneader's pot wall transfers heat to the powder through heat conduction, thus heating it. The liftable pressure cover 5 has a pressure cover heat transfer oil inlet valve 13 and outlet valve 14. Opening these valves allows heat transfer oil to flow into the pressure cover 5, heating it. When the pressure cover 5 is pressed down and comes into contact with the paste, it can... The heat from the heat transfer oil is transferred to the paste. Controlling the temperature of the heat transfer oil and the opening of the inlet and outlet valves can regulate the temperature of the kneader, thereby controlling the material temperature. The kneader has a paste lower temperature measuring point 15 at the bottom for measuring the temperature of the material inside the kneader. The liftable pressure cover 5 has a paste upper temperature measuring point 16 for measuring the temperature of the paste during pressurized kneading. The heat transfer oil heating layer of the kneader has a heat transfer oil temperature measuring point 17 for measuring the temperature of the heat transfer oil. At the same time, the opening of the heat transfer oil inlet valve 11 of the kneader is adjusted through PLC control feedback, thereby achieving precise control of the heat transfer oil temperature.

[0033] The mixing blade 4 is S-shaped and rotates at the same speed. The blade's cut surface forms a 20-45° angle with the pot wall, subjecting the paste to strong compressive and frictional forces between the blade and the pot wall. The overlapping area of ​​the blades exceeds one-third of the blade radius, allowing some paste to be fed into the mixing area of ​​the other blade during operation. This strengthens the cross-linking of the paste between different blades, lengthens the paste's trajectory, and improves the mixing effect.

[0034] First, fine coke powder is added:

[0035] Start the main unit of the kneader and make the mixing blade 4 rotate forward. The lifting cover 5 is lifted upward by the hydraulic rod 6. After it is lifted to the middle limit, open the coke fine powder feed pipe and valve 7 to add the prepared coke fine powder into the kneader. After the feeding is completed, close the coke fine powder feed pipe and valve 7. Solid particle asphalt or powder asphalt can also be added from this feed port.

[0036] Subsequently, a vacuum process was performed:

[0037] The vacuum piping and valve 10 are externally connected to a filter, vacuum gauge, and vacuum pump, serving to create a vacuum; the hydraulic rod 6 controlling the lifting of the pressure plate 5 keeps the liftable pressure plate 5 in a certain position. Figure 3 At the indicated middle limit position, open the vacuum pump and valve. Air inside the mixer is drawn out through the vacuum pipe. Dust raised by the rotating reamer is blocked by the filter. After adding asphalt, close the vacuum valve.

[0038] The upper part of the kneader has a vacuum pipe and valve 10. The valve is connected to an external filter and a vacuum pump. The vacuum pump is used to generate negative pressure, with a maximum negative pressure of -0.09MPa and a flow rate of not less than 8L / s. The filter is used to filter coke powder or asphalt powder in the kneader to prevent the material from being drawn into the vacuum pump.

[0039] After vacuuming is completed, nitrogen can be introduced through the vacuuming pipe to protect the material from oxidation. Alternatively, nitrogen can be introduced during the kneading process when the cap is in the middle limit position to reduce the asphalt oxidation reaction during kneading, accelerate the asphalt condensation reaction, and thus improve the coking value of the paste and the performance of the final product.

[0040] Next, add liquid asphalt:

[0041] The hydraulic rod 6 for lifting the cover makes the liftable cover 5 in the position as follows: Figure 3 At the indicated middle limit position, open the liquid asphalt feed pipe and valve 8, and start the asphalt feeding device to inject liquid asphalt into the mixer; the liquid asphalt feed pipe and valve 8 are directly connected to the outlet of the asphalt tank, thereby preventing air from entering the mixer from the feed inlet. After the asphalt is added, close the liquid asphalt feed pipe and valve 8.

[0042] Pressurized kneading: After adding asphalt and closing the asphalt valve, close the vacuum pipe and valve 10, control the lifting hydraulic rod 6 of the pressure cap to descend so that the liftable pressure cap 5 is pressed down. The pressure cap moves down from the middle limit position. The lifting hydraulic rod 6 of the pressure cap is connected to a hydraulic station, and the pressurization pressure can be set through the PLC control system. The liftable pressure cap 5 has a lower limit position, and it will not go below the lower limit position, thereby avoiding the liftable pressure cap 5 from scraping against the mixing blade 4. After the liftable pressure cap 5 descends to the position, the paste of coke fine powder and asphalt is squeezed around the mixing blade 4 by the pressure cap and the kneading machine pot. Under the action of the blade, it is strongly pressurized and kneaded. At the same time, the friction between the paste and the bottom of the pressure cap generates heat, which makes the temperature of the paste continue to rise and the viscosity of the asphalt further decreases, making it easier to knead with coke fine powder.

[0043] Among them, flue gas treatment:

[0044] During the pressurized kneading process, the fumes generated during kneading will change the pressure inside the kneader from negative to positive. Further fumes will be trapped inside the kneader and unable to escape freely. After kneading for a period of time, the hydraulic rod 6 controlling the lifting of the cap 5 will raise it to the middle limit position, activating the fume extraction device and opening the fume extraction pipe and valve 9 to allow the fumes generated during kneading to escape. After the lifting cap 5 is raised, the paste churns under the action of the mixing blade 4, creating gaps between the paste particles. These gaps are filled with fumes, which can then be discharged through the fume extraction pipe. After the fume extraction is complete, the fume extraction valve is closed, and the hydraulic rod 6 controlling the lifting of the cap 5 is pressed down to continue pressurized kneading. This process of fume extraction and pressurized kneading is repeated until the paste kneading meets the requirements.

[0045] The kneader is equipped with a fume extraction pipe and valve 9, and is connected to an external fume extraction device to remove the fumes generated during the kneading process.

[0046] When extracting flue gas, opening the vacuum valve to introduce nitrogen or air can be used to lower the paste temperature.

[0047] Then, apply pressure and knead:

[0048] The lifting and lowering of the cover 5 is controlled by the hydraulic rod 6, thereby achieving different functions; the liftable cover 5 is in the position of, for example, Figure 2 When the lower limit range is shown, it plays a role in pressurizing and kneading; the adjustable pressure cap 5 is in the position shown. Figure 3 When the device is in the middle limit range shown, operations such as adding coke powder, adding asphalt, extracting flue gas, and vacuuming can be performed; the lifting pressure cap 5 can be positioned as shown in the figure. Figure 4 When the upper limit range is shown, the liftable pressure cap 5 can be fully lifted, and the inside of the kneader is completely connected to the outside for equipment maintenance and other operations.

[0049] Secondly, the batter is removed from the pot:

[0050] The hydraulic rod 6 of the control cap lifting mechanism is used to lift the cap 5 to the middle limit position, the flue gas pipe and valve 9 are opened, the mixing blade 4 is stopped, the discharge port 3 of the kneader is opened, the mixing blade 4 is started to reverse, and the paste is discharged from the discharge port under the action of the blade. After the paste is discharged, the discharge port 3 of the kneader is closed, the flue gas pipe and valve 9 are closed, and the next kneading cycle begins.

[0051] Finally, cool and knead:

[0052] High-pressure kneaders and capping machines can perform high-temperature kneading by using heat transfer oil, or cooling kneading by using refrigerant.

[0053] Raise the liftable pressure cap 5 to the middle limit area, and the hot paste is added to the high-pressure mixer through the coke fine powder feed pipe and valve 7. Alternatively, raise the liftable pressure cap 5 to the upper limit area, and the hot paste is added directly to the high-pressure mixer through the gap between the pot body and the pressure cap. Control the pressure cap lifting hydraulic rod 6 to lower the pressure cap to the lower limit area for pressurized cooling and kneading. Adjust the pressure of the hydraulic station to control the pressurized kneading effect. Raising the pressure cap to the middle limit area allows the flue gas in the mixer to be extracted. Under the action of the circulating coolant, a large amount of heat is carried away from the paste, and the temperature gradually decreases. When the temperature drops to a certain level, the viscosity of the asphalt in the paste increases sharply, the asphalt fluidity deteriorates, and the pressurized kneading effect is not obvious. At this time, raise the pressure cap to the middle limit and stop pressurized kneading. Continue kneading until the paste cools to the required temperature.

[0054] It should be noted here that:

[0055] Lifting cover 5:

[0056] The top of the kneading machine is equipped with a lifting pressure cover 5. The lower radius of the pressure cover coincides with the radius of the mixing blade 4. The lifting pressure cover 5 is connected to the pressure cover lifting hydraulic rod 6. The hydraulic station pressure can reach up to 15MPa. The pressure cover can be kept in a constant pressure state by PLC control. The pressure can be set according to actual needs.

[0057] The cap has a minimum thickness of 100mm, is made of wear-resistant material, and is sealed around the perimeter with a high-temperature resistant sealing strip, with a temperature resistance of no less than 300℃. When the cap is stationary, the vacuum level inside the kneader can reach up to -0.8MPa. The cap has limit grooves for vertical movement to prevent lateral displacement.

[0058] The hydraulic rod 6 for lifting the cover has a limit. The lower limit is used to ensure that the cover does not scrape against the reamer. When the lower limit is in place, the distance between the cover and the reamer is not less than 5mm. The middle and upper limit ranges are adjustable. The upper and lower limits are equipped with physical limit devices.

[0059] The gland is equipped with inlet and outlet valves for heat transfer oil and a temperature measuring device, which can be used to heat kerosene or to cool a cooling medium.

[0060] Mixing reamer 4:

[0061] The kneader uses S-shaped intersecting reamers with a radius of 20–2000 cm. The overlapping area of ​​the reamers exceeds 1 / 3 of the reamer radius. The gap between the reamer and the kneader pot wall is no higher than 2 mm. The angle between the side of the reamer and the pot wall is 20–45°. The reamer is a hollow reamer made of high-strength steel with an internal through-hole diameter of 20–100 mm.

[0062] Vacuum pumping device:

[0063] The vacuum device can switch between vacuuming, nitrogen supply, and cold air supply functions by switching valves; the vacuuming pipeline can be located above the side wall of the mixer or installed on the pressure cap.

[0064] Smoke extraction device:

[0065] It is equipped with a flue gas extraction pipe and valve, and is externally connected to a negative pressure gauge and a flue gas extraction device. The flue gas extraction time and negative pressure can be automatically controlled by a PLC system. The flue gas extraction pipe and valve 9 can be located above the side wall of the kneader or installed on the pressure cap.

[0066] High-powered kneader:

[0067] The kneader has an effective volume ranging from 30L to 8000L and is equipped with a heat transfer oil heating layer with a thickness of 50-150mm. The heating layer can be circulated with hot kerosene or a cooling medium and has a pressure resistance of not less than 1.5MPa. The heat transfer oil inlet and outlet are equipped with valves, and the inlet valve is connected to a PLC system for automatic temperature control of the kneader.

[0068] The kneading machine pot is made of high-strength wear-resistant steel with a thickness of not less than 10mm, an internal pressure of not less than 5MPa, and a temperature resistance of not less than 400℃.

[0069] The discharge port 3 of the mixer adopts a bottom discharge method. The bottom of the mixer is equipped with a distribution cone to distribute the paste tumbled by the reamer to the range of motion of another reamer.

[0070] The kneader has multiple temperature measuring points for measuring the temperature of heat transfer oil or cooling medium, kneader, coke powder, paste, capping, etc.

[0071] The insulation layer of the kneading machine should be at least 50mm thick and have a temperature resistance of at least 400℃.

[0072] The kneader is equipped with a coke fine powder feed pipe and valve 7, and a liquid asphalt feed pipe and valve 8, located on the side wall or the pressure cover of the kneader.

[0073] The kneading machine is equipped with a PLC control system, which includes functions such as equipment interlocking. It can be operated manually, semi-automatically, and fully automatically, and has remote control capabilities.

[0074] Further Example 1

[0075] Heat transfer oil at 220℃ is introduced into the kneader to heat the kneader to 200℃. The pressure cap is controlled to the middle limit. 1100kg of coke fine powder with D50 of 16μm is added.

[0076] Start the reamer to rotate forward for preheating, and open the flue gas pipe valve to remove moisture from the coke powder.

[0077] After preheating for 2 hours, the temperature of the coke powder rises to 185℃. The flue gas pipeline valve is closed, and the vacuum pump and vacuum valve are opened. After vacuuming for 30 minutes, the negative pressure inside the kneader reaches -0.08MPa.

[0078] Open the asphalt feed valve and add 485 kg of liquid asphalt at 210°C. This asphalt is high-temperature asphalt with a softening point of 118°C.

[0079] After adding asphalt, close the vacuum valve, control the pressure cap to descend to the lower limit area, and control the hydraulic station pressure to 6MPa for pressurized mixing.

[0080] After kneading under pressure for 20 minutes, lift the pressure cap to the middle limit area, start the exhaust gas device, open the exhaust gas valve, and discharge the exhaust gas from the kneader.

[0081] After extracting flue gas for 20 minutes, close the flue gas valve, control the pressure cap to descend to the lower limit area and continue pressurizing and kneading. Adjust the hydraulic station pressure to 7MPa and pressurize and knead for 30 minutes.

[0082] After that, continue to extract the flue gas for 20 minutes, then pressurize at 8MPa and knead for 30 minutes.

[0083] The total kneading time is 120 minutes, the paste temperature is 260℃. Lift the pressure cap to the middle limit, close the reamer, open the exhaust gas device and valve, open the kneader outlet 3, start the reamer to reverse and discharge the paste from the kneader. After the paste is discharged, close the kneader outlet 3, turn off the exhaust gas device, and enter the next production cycle.

[0084] After mixing, the paste tested had a volatile content of 12.4% and a bulk density of 1.72 g / cm³. 3 The crushing strength of 1-2mm particles is 62%, and the bulk density of the product after one-time calcination and graphitization is 1.82 g / cm³. 3 Flexural strength 58MPa.

[0085] Example 2

[0086] Heat transfer oil at 230℃ is introduced into the kneader to heat the kneader to 210℃. The pressure cap is controlled to the middle limit. The reamer is started to rotate forward. 1100kg of coke fine powder with D50 of 16μm and 475kg of asphalt powder are added.

[0087] This asphalt is a high-temperature asphalt with a softening point of 130℃.

[0088] The pressure cap is lowered to the lower limit area, and the hydraulic station pressure is controlled to 4MPa for pressurized kneading.

[0089] After kneading under pressure for 15 minutes, lift the pressure cap to the middle limit area, start the exhaust gas device, open the exhaust gas valve, and discharge the exhaust gas from the kneader.

[0090] After extracting flue gas for 15 minutes, close the flue gas valve, control the pressure cap to descend to the lower limit area and continue pressurizing and kneading. Adjust the hydraulic station pressure to 6MPa and pressurize and knead for 20 minutes.

[0091] After that, continue to extract the flue gas for 15 minutes, pressurize at 8MPa and knead for 30 minutes, extract the flue gas for 15 minutes, pressurize at 10MPa and knead for 30 minutes.

[0092] The total kneading time is 140 minutes, the paste temperature is 250℃, the pressure cap is lifted to the middle limit, the reamer is closed, the exhaust gas device and valve are turned on, the discharge port 3 of the kneader is opened, the reamer is started to reverse and discharge the paste from the kneader. After the paste is discharged, the discharge port 3 of the kneader is closed, the exhaust gas device is turned off, and the next production cycle begins.

[0093] After mixing, the paste tested had a volatile content of 11.8% and a bulk density of 1.70 g / cm³. 3The crushing strength of 1-2mm particles is 58%. After one-time calcination and graphitization, the bulk density of the product is 1.80 g / cm³. 3 Flexural strength 55MPa.

[0094] The kneading machine is equipped with a cap lifting hydraulic rod 6 and a liftable cap 5. The cap lifting hydraulic rod 6 is connected to the hydraulic station. The hydraulic rod drives the cap to move downward, thereby pressing the paste downward and filling the space between the cap and the reamer, thus achieving pressurized kneading. The pressure of the hydraulic station is controlled by the PLC, thereby achieving pressurized kneading with different intensities. The maximum pressure of the hydraulic station can reach 15MPa. The pressure applied to the paste by the cap can be freely adjusted by the PLC.

[0095] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0096] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-efficiency pressure kneading device for special carbon graphite materials, comprising a kneading machine body and a heating layer (1), a mixing blade (4), and a liftable pressure cap (5), characterized in that: A kneader insulation layer (2) is provided on the outer wall of the kneader body and heating layer (1). A cover lifting hydraulic rod (6) is provided on the top of the kneader body and heating layer (1). A liftable cover (5) is installed at the output end of the cover lifting hydraulic rod (6). Mixing blades (4) are installed on both sides inside the kneader body and heating layer (1). A paste upper temperature measuring point (16) is provided in the middle position inside the liftable cover (5). A kneader discharge port (3) is provided in the middle position at the bottom of the kneader body and heating layer (1). A paste lower temperature measuring point (15) is provided in the middle position inside the kneader discharge port (3).

2. The high-efficiency pressure mixing device for special carbon graphite materials according to claim 1, characterized in that: On the right side of the kneader body and heating layer (1), there is a coke fine powder feed pipe and valve (7) and a liquid asphalt feed pipe and valve (8). The coke fine powder feed pipe and valve (7) is located above the liquid asphalt feed pipe and valve (8). On the left side of the kneader body and heating layer (1), there is a flue gas pipe and valve (9) and a vacuum pipe and valve (10). The vacuum pipe and valve (10) is located above the flue gas pipe and valve (9).

3. The high-efficiency pressure mixing device for special carbon graphite materials according to claim 2, characterized in that: The right side of the kneader body and heating layer (1) is provided with a kneader heat transfer oil outlet valve (12) and a kneader heat transfer oil temperature measuring point (17). The kneader heat transfer oil outlet valve (12) is located below the liquid asphalt feed pipe and valve (8) and above the kneader heat transfer oil temperature measuring point (17). The left side of the kneader body and heating layer (1) is provided with a kneader heat transfer oil inlet valve (11). The kneader heat transfer oil inlet valve (11) is located below the flue gas pipe and valve (9). The right side of the top of the liftable pressure cover (5) is provided with a pressure cover heat transfer oil outlet valve (14), and the left side of the top of the liftable pressure cover (5) is provided with a pressure cover heat transfer oil inlet valve (13).

Images