Negative pressure pneumatic conveying system capable of rapidly cooling powder and control method

Abstract

The invention provides a negative-pressure pneumatic conveying system capable of rapidly cooling powder and a control method, and the system comprises a powder bin used for storing high-temperature powder; the air inlet cooling unit is used for preparing cold air with preset low temperature; the mixer is used for mixing the high-temperature powder and cold air and rapidly cooling the high-temperature powder; the negative pressure collector is used for collecting the cooled powder through settling separation, and secondary cooling is carried out on the powder by utilizing a liquid cooling close-packed pipe arranged in the negative pressure collector; and the bin pump material receiving opening is used for opening the ash discharging valve to discharge materials outwards when the powder materials in the negative pressure collector are monitored to reach the preset material level. Compared with powder storage natural cooling or powder conveying cooling by adopting a water cooling jacket or a plate heat exchanger, the powder is fully mixed and cooled with the cold source gas through the especially large specific surface area, rapid cooling is achieved in the powder conveying process, the plant area and the equipment height are greatly reduced, the cooling efficiency is improved, and the production cost is reduced. And the time cost, the investment cost and the production cost are also saved.

Description

Technical Field

[0001] The present application relates to the technical field of material conveying, and in particular to a negative pressure pneumatic conveying system and a control method for rapidly cooling powder. Background Art

[0002] In the related art, when cooling the powder, a cooling tower is usually used to cool the powder and then the powder is blown into a powder pile or a conveying pipeline to achieve the purpose of cooling. Alternatively, when the powder is transported in a pipeline, a coolant is set on the outer wall of the pipeline to cool the powder to achieve the purpose of cooling.

[0003] However, the above method has the following defects. On the one hand, a special cooling device is required, which is not only time-consuming and labor-intensive to lay, but also occupies a large plant area and has a high construction cost. On the other hand, it takes a long time to wait for cooling, resulting in low cooling efficiency and failure to achieve the purpose of rapid cooling. Summary of the invention

[0004] In view of the above-mentioned shortcomings of the prior art, the purpose of the present application is to provide a negative pressure pneumatic conveying system and a control method for rapidly cooling powder, so as to solve the problem that the dust cannot be rapidly cooled during transmission in the prior art.

[0005] To achieve the above-mentioned purpose and other related purposes, the first aspect of the present application provides a negative pressure pneumatic conveying system for rapidly cooling powder, including: a powder silo for storing high-temperature powder; an air intake cooling unit for preparing cold air at a preset low temperature; a mixer, whose input end pipeline is connected to the powder silo and the air intake cooling unit, and is used to mix the high-temperature powder with the cold air, and rapidly cool the high-temperature powder by heat exchange to obtain cooled powder; a negative pressure collector, a pipeline connected to the output end of the mixer, collects the cooled powder by sedimentation and filter separation, and uses the liquid-cooled dense pipes provided in the negative pressure collector to perform secondary cooling on the cooled powder to obtain low-temperature powder; a silo pump receiving port is arranged at the bottom of the negative pressure collector, and is used to monitor that when the low-temperature powder reaches a preset material level, open the ash discharge valve to connect to the silo pump receiving port for unloading to the outside.

[0006] In certain embodiments of the first aspect of the present application, the upper portion of the negative pressure collector is connected to a compressed air source to spray the filter material separated by sedimentation, clean the cooling powder attached to the surface of the filter material, and output clean air.

[0007] In certain embodiments of the first aspect of the present application, it also includes: a vacuum pump and an exhaust fan of the negative pressure collector are connected in sequence by pipelines, negative pressure is provided to the negative pressure collector by the vacuum pump, the exhaust fan is used to discharge the clean air, and the muffler is arranged at the output end of the exhaust fan to mute the clean air.

[0008] In certain embodiments of the first aspect of the present application, it also includes: a first residual pressure valve and a second residual pressure valve, the first residual pressure valve is arranged between the intake air cooling unit and the mixer, and the second residual pressure valve is arranged between the vacuum pump and the exhaust fan to maintain the pressure balance between the negative pressure pneumatic conveying system and the exhaust system.

[0009] In certain embodiments of the first aspect of the present application, it also includes: a variable frequency discharge port, which is arranged below the powder silo, and adaptively adjusts the discharge speed of the powder silo according to the real-time temperature of the low-temperature powder received by the negative pressure collector.

[0010] In certain embodiments of the first aspect of the present application, a fluidizing device is provided at the lower portion of the negative pressure collector for uniformly outputting and cooling the temperature-reduced powder.

[0011] In certain embodiments of the first aspect of the present application, the liquid-cooled close-packed pipes are provided with flowing cooling liquid.

[0012] In certain embodiments of the first aspect of the present application, the pipeline is a seamless steel pipe, and the inner lining of the seamless steel pipe is a ceramic wear-resistant part.

[0013] The second aspect of the present application provides a control method for a negative pressure pneumatic conveying system for rapidly cooling powder, comprising: if it is monitored that the high-temperature powder stored in the powder silo reaches a preset material level threshold, the air intake cooling unit is turned on to output cold air of a preset low temperature; at the same time, the frequency conversion discharger at the lower end of the powder silo is slowly opened to allow the high-temperature powder to continue to fall into the mixer; the cold air is mixed with the high-temperature powder, and the high-temperature powder is rapidly cooled by heat exchange to obtain cooled powder; the cooled powder is collected by sedimentation and filter material separation, the filter material separated by sedimentation is sprayed, the cooled powder attached to the surface of the filter material is cleaned, and clean air is output; and the collected cooled powder is cooled for a second time by using the liquid-cooled dense pipes in the negative pressure collector to obtain low-temperature powder; if it is monitored that the low-temperature powder in the negative pressure collector reaches a preset material level, the ash discharge valve is opened to connect the silo pump material receiving port to discharge the material to the outside.

[0014] In certain embodiments of the second aspect of the present application, it also includes: monitoring the real-time temperature of the low-temperature powder, and if the real-time temperature meets the preset temperature range, maintaining the unloading speed of the powder bin and maintaining the air volume of the intake air cooling unit, wherein the unloading speed of the powder is matched with the air volume of the cold air; or, if the real-time temperature is higher than the preset temperature range, reducing the unloading speed of the powder bin and / or increasing the air volume of the intake air cooling unit; or, if the real-time temperature is lower than the preset temperature range, increasing the unloading speed of the powder bin and / or reducing the air volume of the intake air cooling unit.

[0015] As described above, a technical solution of a negative pressure pneumatic conveying system and control method for rapidly cooling powder materials described in the present application has the following beneficial effects:

[0016] In the pipeline transmission, the present application can quickly reduce the temperature of the powder by mixing cold air with the high-temperature powder and then quickly exchanging heat. Compared with other cooling methods, it not only cools down quickly, but also saves cooling costs; at the same time, the cooling powder is collected by sedimentation and filter separation, avoiding leakage of the powder during the cooling process; the cooling powder is cooled by the liquid-cooled dense pipe in the negative pressure collector for a second time to ensure that the cooling powder reaches the required low temperature. This dual cooling mechanism significantly improves the cooling effect. In addition, the material level of the low-temperature powder is monitored in real time. When the material level reaches the preset material level, the ash discharge valve is opened to connect the silo pump receiving port for external discharge. The whole process is automated, which improves the efficiency of the negative pressure pneumatic conveying system. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Shown is a structural block diagram of a negative pressure pneumatic conveying system for rapidly cooling powder provided by the present application;

[0018] Figure 2 Shown is a control flow chart of a negative pressure pneumatic conveying system for rapidly cooling powder provided by the present application. DETAILED DESCRIPTION

[0019] The following describes the embodiments of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0020] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application, and thus the drawings only show components related to the present application rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed at will, and the component layout may also be more complicated.

[0021] See also Figure 1 , which is a structural block diagram of a negative pressure pneumatic conveying system for rapid cooling of powder provided by this application, is described in detail as follows:

[0022] Powder bin 1, used for storing high-temperature powder;

[0023] Exemplarily, the powder silo provides a stable powder storage environment to prevent the powder from being damp, oxidized, or affected by other adverse factors during storage; at the same time, its sealing design ensures the continuity and stability of the powder during transportation. For example, the material of the powder silo is selected according to the properties of the powder, such as stainless steel, wear-resistant alloy, etc., to improve the durability and corrosion resistance of the powder silo. Specifically, the powder silo is a sealed container with a feed port and a discharge port. The warm powder enters the powder silo through the feed port, is stored until it is needed, and is discharged through the discharge port.

[0024] Inlet air cooling unit 2, used for preparing cold air at a preset low temperature;

[0025] For example, the intake air cooling unit is based on a refrigeration cycle, and cools the gas to a preset low temperature state through processes such as compression, condensation, expansion and evaporation. For example, the gas is compressed by a compressor, and the high-temperature and high-pressure gas is cooled into a high-pressure liquid by a condenser; the high-pressure liquid is then depressurized and partially evaporated by an expansion valve, absorbing heat to obtain low-temperature and low-pressure cold air, which is then cooled by an evaporator and transported to a mixer. In addition, a heat pump device can be added to the intake air cooling unit to improve refrigeration efficiency and reduce energy consumption.

[0026] The mixer 3, whose input end pipeline is connected to the powder bin and the air intake cooling unit, is used to mix the high-temperature powder with the cold air, and rapidly cool the high-temperature powder by heat exchange to obtain cooled powder;

[0027] Exemplarily, the mixer utilizes the shear force and turbulence effect generated by the stirring device to fully contact and mix the high-temperature powder with the cold air. Through heat exchange, the cold air absorbs the heat in the powder, thereby reducing the temperature of the powder. For example, when the high-temperature powder and the cold air enter the mixer at the same time, the two are fully mixed by stirring; the high-temperature powder is rapidly cooled by heat exchange to form a cooled powder. In addition, a cooling device can be added to adjust the temperature in the mixer and improve the mixing efficiency; or, the stirring device includes but is not limited to a turbine or a propeller.

[0028] A negative pressure collector 4, connected to the output end of the mixer by a pipeline, collects the cooled powder by sedimentation and filter separation, and uses the liquid-cooled dense pipes provided in the negative pressure collector to perform secondary cooling on the cooled powder to obtain low-temperature powder;

[0029] For example, the negative pressure collector uses the suction force generated by negative pressure to suck the cooled powder into the collector; the powder is separated from the gas by sedimentation and filter separation; at the same time, the liquid-cooled dense pipe performs secondary cooling on the powder to meet specific temperature requirements (pre-set by the user according to needs). For example, the filter material (such as Figure 1The filter 6) shown includes but is not limited to metal mesh, cloth bag, etc., to adapt to different powder properties. It should be noted that the filter can be set inside the negative pressure collector, or inside and outside the negative pressure collector. When set outside the negative pressure collector, it is set at the output end of the heat exchanger 5. Alternatively, a fluidizing device is provided at the lower part of the negative pressure collector for uniform output and cooling of the powder. For example, the fluidizing device is a vibration device to improve the filtering efficiency and the settling speed of the cooling powder.

[0030] It should be understood that the filter material should be selected appropriately considering the characteristics of dust, for example, dust filtration is performed by sedimentation and pleated crawler filtration separation, or pleated filter bags for dust removal filtration of the overall equipment, and the filter material adopts the currently advanced antistatic nanofiber coated pleated filter bags, and the filter material should have nano-coated high filtration accuracy, flame retardant, and antistatic functions. Since the liquid-cooled dense pipe is filled with coolant, for example, taking the cooling cost as the minimum, a water-cooled dense pipe with a two-layer structure is selected to improve the cooling efficiency.

[0031] The silo pump receiving port is arranged at the bottom of the negative pressure collector, and is used to monitor that when the low-temperature powder reaches a preset material level, open the ash discharge valve to connect to the silo pump receiving port and discharge the material to the outside.

[0032] For example, the silo pump inlet uses a sensor to monitor the material level of the powder. When the material level reaches a preset level, the ash discharge valve is controlled to open, so that the powder is discharged through the silo pump, thus ensuring the continuous transportation and storage of the powder. Specifically, the material level of the collected low-temperature powder is monitored in real time by a material level sensor. Of course, an ultrasonic sensor, a photoelectric sensor or a weight sensor can also be used for triggering.

[0033] In addition, it should be noted that a porous net is provided below the powder bin and in the pipeline of the mixer to prevent powder congestion, and its function is similar to that of a powder vibration device.

[0034] Through the above method, during the pipeline transmission, the powder can quickly reduce the temperature of the powder by mixing the cold air with the high-temperature powder and then quickly exchanging heat. Compared with other cooling methods, it not only cools down quickly, but also saves cooling costs; at the same time, the cooling powder is collected by sedimentation and filter separation, which avoids leakage of the powder during the cooling process; the cooling powder is cooled by the liquid-cooled dense pipe in the negative pressure collector for a second time to ensure that the cooling powder reaches the required low temperature. This dual cooling mechanism significantly improves the cooling effect. In addition, the material level of the low-temperature powder is monitored in real time. When the material level reaches the preset level, the ash discharge valve is opened to connect the silo pump receiving port for external discharge. The whole process is automated, which improves the efficiency of the negative pressure pneumatic conveying system.

[0035] Optionally, in some embodiments, the upper portion of the negative pressure collector is connected to a compressed air source to spray the filter material separated by sedimentation, clean the cooling powder attached to the surface of the filter material, and output clean air, wherein the filter material is a high-temperature filter material.

[0036] Among them, the filter material after sedimentation and separation is sprayed with compressed air of 0.6MPa in the factory area to clean the cooling powder attached to the surface of the filter material. The compressed air source can not only clear the powder, but also cool it down and output clean air. It should be noted that the filter material is arranged at the upper end of the negative pressure collector, or the filter material and the negative pressure collector are integrated so that the cooling powder after cleaning can be collected together.

[0037] For example, a compressed air source is connected to the upper part of the negative pressure collector. When cleaning the cooling powder on the surface of the filter material, the compressed air source is turned on and the compressed air is delivered to the blowing device inside the negative pressure collector through a pipeline. The compressed air is sprayed out at a certain pressure and flow rate to clean the filter material. During the spraying process, the cooling powder is blown off by the compressed air and discharged through the dust discharge device of the negative pressure collector; at the same time, the clean air is filtered by the filter material and then output to the outside.

[0038] Through the above method, using compressed air for spray cleaning can quickly clean the cooling powder on the surface of the filter material, improve the cleaning efficiency, and achieve the purpose of unblocking the powder and reducing the temperature of the powder; by cleaning the dust on the surface of the filter material, it can reduce the blockage and wear of the filter material, thereby extending the service life; the filter material can remove tiny particles and impurities in the air to ensure the quality of the output air. In addition, using compressed air for spray cleaning has simple equipment, convenient operation, and low maintenance cost.

[0039] Optionally, in some embodiments, it also includes: a vacuum pump 7 and an exhaust fan 8 of the negative pressure collector are connected in sequence by pipelines, the vacuum pump 7 is used to provide negative pressure for the negative pressure collector, the exhaust fan is used to discharge the clean air, and the muffler silences the clean air after filtration and purification.

[0040] Among them, the vacuum pump and the exhaust fan are arranged outside the negative pressure collector. The vacuum pump extracts air through the mechanical movement generated by electricity, and discharges the extracted gas into the atmosphere through the exhaust port, thereby forming a negative pressure at the suction port. The vacuum pump can adopt multiple groups of vacuum pumps, for example, a main vacuum pump and a backup vacuum pump, to improve the stable output capacity of the vacuum pump, or meet the needs of different negative pressures.

[0041] For example, a muffler is usually installed near the exhaust port of an exhaust fan to reduce the noise generated when air is discharged. Since the muffler contains multiple chambers and pipe structures, these structures can reflect, interfere and absorb sound waves, thereby reducing the propagation of noise; at the same time, the muffler is filled with sound-absorbing materials such as foam plastics, glass fiber, etc., which enhances the noise reduction effect.

[0042] Optionally, in some embodiments, it also includes: a first residual pressure valve 10 and a second residual pressure valve 11, the first residual pressure valve 10 is arranged between the intake air cooling unit and the mixer, and the second residual pressure valve 11 is arranged between the vacuum pump and the exhaust fan to maintain the pressure balance between the negative pressure pneumatic conveying system and the exhaust system.

[0043] For example, in a negative pressure pneumatic conveying system, the first residual pressure valve is arranged between the intake air cooling unit and the mixer. After the intake air cooling unit cools the incoming gas, the gas enters the first residual pressure valve through the pipeline. The first residual pressure valve automatically adjusts its opening degree according to the pressure change in the system to maintain a stable pressure in the system. When the pressure in the system increases, the first residual pressure valve automatically opens to release part of the pressure; when the pressure in the system decreases, it automatically closes to prevent outside air from entering.

[0044] The second residual pressure valve is set between the vacuum pump and the exhaust fan. The vacuum pump maintains the negative pressure state by extracting the gas in the system. The second residual pressure valve automatically adjusts its opening degree according to the pressure change at the outlet of the vacuum pump to ensure that the vacuum pump can work stably and efficiently. When the negative pressure at the outlet of the vacuum pump increases, the second residual pressure valve automatically opens to release part of the pressure; when the negative pressure decreases, it automatically closes.

[0045] Through the above method, not only can the pressure balance between the system and the discharge system be automatically adjusted to keep it within the preset pressure range, thus ensuring the stable operation of the system (i.e., the negative pressure pneumatic conveying system); by accurately controlling the pressure within the system, energy loss is reduced and the energy utilization efficiency of the entire system is improved; at the same time, the pressure on the equipment is reduced and the service life of the equipment is ensured.

[0046] Optionally, in some embodiments, it further includes: a variable frequency discharge port 9, which is arranged below the powder bin and adaptively adjusts the discharge speed of the powder bin according to the real-time temperature of the low-temperature powder received by the negative pressure collector.

[0047] Exemplarily, the variable frequency discharge port is set below the powder bin, and the variable frequency discharge port is connected to the motor through a frequency converter, so as to achieve precise control of the discharge speed. By monitoring the real-time temperature information of the low-temperature powder and feeding it back to the control system, for example, according to the received real-time temperature information, the output frequency of the frequency converter is automatically adjusted, and then the speed of the motor is changed, so as to achieve adaptive adjustment of the discharge speed, and achieve the effect of accurately cooling the powder.

[0048] Through the above method, on the one hand, the frequency conversion speed regulation technology is used to automatically adjust the feeding speed according to the real-time temperature of the powder, so as to achieve precise control of the feeding speed, thereby ensuring the stable output of the powder and the stable operation of the system; on the other hand, the frequency conversion discharge port can adjust the speed of the motor according to actual needs, so as to save energy.

[0049] Optionally, in some embodiments, the liquid-cooled tight-packed pipe (such as Figure 1 The heat exchanger 5 is provided with flowing coolant.

[0050] For example, the liquid cooling tube is designed as a metal plate with high heat conduction performance, and a channel for the flow of coolant is arranged inside the metal plate. The coolant inlet and outlet are connected to the internal channel of the liquid cooling tube by welding or other connection methods to form a complete coolant circulation system.

[0051] Through the above method, the collected cooled powder is cooled for a second time, thereby improving the cooling efficiency of the powder.

[0052] Optionally, in some embodiments, the pipeline is a seamless steel pipe, and the inner lining of the seamless steel pipe is a ceramic wear-resistant part.

[0053] For example, the thickness of the steel pipe is greater than or equal to 3 mm, and a seamless steel pipe with a thickness of 8 mm is lined with ceramic wear-resistant parts, and elbows, tees, reducers, and valves are lined with ceramic wear-resistant parts.

[0054] Through the above method, since the seamless steel pipe has high mechanical strength and pressure bearing capacity, it can withstand greater pressure and load. Ceramic wear-resistant parts of preset thickness are arranged in the seamless steel pipe. The high hardness, high wear resistance and high corrosion resistance of the ceramic wear-resistant parts are utilized to combine the ceramic layer with the seamless steel pipe to form a composite pipeline. It should be noted that the ceramic layer can effectively reduce the wear and corrosion of the pipeline during the transportation process and extend its service life. At the same time, its service life is relatively long, which can reduce the frequency of replacement and maintenance.

[0055] Optionally, in practical applications, the negative pressure pneumatic conveying system for rapidly cooling powder materials is implemented as follows:

[0056] The dust in the ash bin of the dust collector falls continuously and uninterruptedly into the lower ash bin through the lower star-shaped ash discharge valve. A level meter is installed in the ash bin, and an electric gate valve is installed at the bottom of the ash bin. When the level meter detects a high material level, it sends a signal to control the electric two-way valve to open, and the air enters the negative pressure conveying pipe. The electric gate valve slowly opens, and the dust gradually falls and mixes with the air. The material is transported to the dust collector and ash storage bin through the dilute phase conveying pipe. The purified clean gas meets the discharge standards after passing through the vacuum pump and muffler. This application uses a vacuum pump as the power source to provide negative pressure. A high negative pressure bag dust collector is used for dust separation and is equipped with an ash storage bin, an ash discharge valve and a gate valve (integrated device), and a filter is used for ash mixing and air collection.

[0057] Considering that dust has a certain degree of abrasiveness on pneumatic conveying pipelines, 8mm thick-walled seamless steel pipes are lined with ceramic wear-resistant parts. Elbows, tees, reducers and valves are lined with ceramic wear-resistant parts. At the same time, because the working body of the equipment and the silicon powder belong to the same zone, all equipment must consider dust explosion-proof design.

[0058] In addition, the pneumatic conveying pipeline and some valves are installed on the roof, the main part of the pneumatic conveying dust removal unit is installed on the east side of the bottom of the building, and the middle part is all connected with seamless steel pipes.

[0059] It should be noted that the filtration efficiency of the pleated filter bag should be ≥99.8%, and the dust concentration discharged to the outdoor air after treatment should be ≤10mg / m 3 , a detection port is reserved on the exhaust pipe. According to the dust characteristics, the filtration wind speed is designed to be less than 0.6m / min, and the wind speed of the box section is less than 2.5m / s. The advanced cleaning controller is adopted, and the spraying interval and pulse width can be adjusted; the cleaning controller has pressure difference, timing, and offline cleaning functions; the electromagnetic pulse valve is pilot-operated, and the pipelines are installed neatly and beautifully.

[0060] It should also be noted that the ash storage bin at the lower end of the negative pressure dust collector has a cyclone function. The shell material thickness of the cyclone dust collector is 5mm, and the wear resistance of the powder is fully considered (a 5mm ceramic lining needs to be installed). The straight cylinder and the conical cylinder are connected by flanges and cannot be directly welded. The legs must meet the strength and wind / vibration resistance requirements.

[0061] Through the above method, compared with the natural cooling of powder during storage or the cooling of powder during transportation using a water-cooled jacket or a plate heat exchanger, the powder is fully mixed and cooled with the cold source gas due to its particularly large specific surface area, and rapid cooling is achieved during powder transportation, which greatly reduces the plant area and powder temperature, not only improving the cooling efficiency, but also saving time cost, investment cost and production cost.

[0062] See also Figure 2 , which is a control flow chart of a negative pressure pneumatic conveying system for rapidly cooling powder provided in the present application, including:

[0063] Step S201, if it is monitored that the high-temperature powder stored in the powder bin reaches a preset material level threshold, the air intake cooling unit is turned on to output cold air at a preset low temperature; at the same time, the variable frequency discharger at the lower end of the powder bin is slowly opened to allow the high-temperature powder to continue to fall into the mixer;

[0064] Specifically, the material level sensor installed in the powder silo monitors the high-temperature powder stock in the powder silo in real time. When the material level sensor detects that the powder stock reaches the preset material level threshold, the automatic control system triggers the air intake cooling unit to start and output cold air with a preset low temperature; at the same time, the frequency conversion discharger at the lower end of the powder silo is slowly opened by the electric actuator to control the flow of the high-temperature powder so that it continues to fall into the mixer.

[0065] Step S202, mixing the cold air with the high-temperature powder, and rapidly cooling the high-temperature powder by heat exchange to obtain cooled powder;

[0066] Specifically, the cold air and the high-temperature powder are fully mixed in the mixing area of ​​the mixer, and the temperature difference between the cold air and the high-temperature powder is used for heat exchange to quickly reduce the temperature of the powder.

[0067] Step S203, collecting the cooling powder by sedimentation and filter material separation, spraying the filter material separated by sedimentation to clean the cooling powder attached to the surface of the filter material, and outputting clean air; and performing secondary cooling on the collected cooling powder by using the liquid-cooled close-packed pipe in the negative pressure collector to obtain low-temperature powder;

[0068] Specifically, the cooled powder is initially separated by sedimentation, and the impurities in the powder are further separated by filter material. During separation, the filter material is sprayed and cleaned with the help of compressed air source to ensure that the filter material is unobstructed. The collected cooled powder is cooled for a second time by the liquid-cooled dense pipes in the negative pressure collector to obtain low-temperature powder.

[0069] Step S204, if it is monitored that the low-temperature powder in the negative pressure collector reaches a preset material level, the ash discharge valve is opened to connect to the silo pump material receiving port to discharge the material to the outside.

[0070] Specifically, the inventory of low-temperature powder is monitored in real time by a material level sensor installed in the negative pressure collector; when the material level sensor detects that the inventory of low-temperature powder reaches a preset material level, the automatic control system triggers the ash discharge valve to open, connects the silo pump material inlet, and discharges the material to the outside.

[0071] In the prior art, since powder can be used to manufacture key components such as solar panels and energy storage equipment, it is often necessary to cool down quickly. In a pneumatic conveying pipeline less than 30 meters, the air intake cooling unit generates a cold air volume of 5 to 8 degrees Celsius, and the wind speed is about 30 meters per second. The initial temperature of the high-temperature powder is less than 200 degrees Celsius. In nearly 1 second, the negative pressure pneumatic conveying system for rapid cooling of the powder of the present application is used to quickly cool the powder to 60 to 80 degrees Celsius through cold air heat exchange, so as to achieve the effect of continuous rapid cooling.

[0072] Through the above method, during pipeline transmission, the powder is mixed with cold air and then quickly heat exchanged, ensuring that the high-temperature powder is quickly cooled down in a short time. Compared with other cooling methods, not only is the cooling fast, but also the cooling cost is saved; at the same time, the cooled powder is collected by sedimentation and filter separation, avoiding leakage of the powder during the cooling process; and the liquid-cooled dense pipes in the negative pressure collector are used to perform secondary cooling on the cooled powder to ensure that the cooled powder reaches the required low temperature. This dual cooling mechanism significantly improves the cooling effect; in addition, the material level of the low-temperature powder is monitored in real time. When the material level reaches the preset level, the ash discharge valve is opened to connect the silo pump receiving port for external discharge. The entire process is automated, improving the efficiency of the negative pressure pneumatic conveying system.

[0073] Optionally, in certain embodiments, it also includes: monitoring the real-time temperature of the low-temperature powder, and if the real-time temperature satisfies a preset temperature range, maintaining the unloading speed of the powder bin and maintaining the air volume of the intake air cooling unit, wherein the unloading speed of the powder and the air volume of the cold air match each other; or, if the real-time temperature is higher than the preset temperature range, reducing the unloading speed of the powder bin and / or increasing the air volume of the intake air cooling unit; or, if the real-time temperature is lower than the preset temperature range, increasing the unloading speed of the powder bin and / or reducing the air volume of the intake air cooling unit.

[0074] For example, if the real-time temperature of the powder material meets the preset temperature range, the feeding speed of the powder material and the air volume of the cold air are matched, that is, once the feeding speed of the powder bin is adjusted, the air volume of the intake air cooling unit also needs to be adjusted. For example, if the feeding speed is increased, the air volume of the intake air cooling unit should also be increased; similarly, if the feeding speed is reduced, the air volume of the intake air cooling unit should also be reduced.

[0075] Exemplarily, if the real-time temperature of the powder is higher than the preset temperature range, the strategy of reducing the material discharge speed of the powder bin or / and increasing the air volume of the intake cooling unit is adopted to control the negative pressure pneumatic conveying system. If the real-time temperature is lower than the preset temperature range, the strategy of increasing the material discharge speed of the powder bin or / and reducing the air volume of the intake cooling unit is adopted to control the negative pressure pneumatic conveying system.

[0076] Through the above method, when the real-time temperature meets the preset temperature range, maintaining a stable feeding speed and air volume can avoid unnecessary energy waste; at the same time, by accurately controlling the feeding speed and air volume, energy consumption can be further reduced and energy utilization efficiency can be improved; by adjusting the feeding speed and air volume, the suspension state and conveying speed of the material in the pipeline can be maintained, thereby avoiding problems such as blockage and wear; if the real-time temperature of the powder is higher or lower than the preset temperature range, different control strategies are used to accurately control the feeding speed and air volume, which can ensure the stability and continuity of the material during the conveying process, thereby improving production efficiency; at the same time, it can also reduce downtime caused by equipment failure and further improve production efficiency. In addition, by real-time monitoring and adjusting the temperature, it can ensure that the powder maintains the best process conditions during the conveying and processing process, thereby ensuring the quality and stability of the powder.

[0077] The specific definition of the control method of the negative pressure pneumatic conveying system for rapid cooling of powder can be found in the above definition of the negative pressure pneumatic conveying system for rapid cooling of powder, which will not be repeated here. Each module in the above-mentioned negative pressure pneumatic conveying system for rapid cooling of powder can be implemented in whole or in part by software, hardware and a combination thereof. The above-mentioned modules can be embedded in or independent of the processor in the electronic device in the form of hardware, or can be stored in the memory of the electronic device in the form of software, so that the processor can call and execute the operations corresponding to the above modules.

[0078] The above embodiments are merely illustrative of the principles and effects of the present application and are not intended to limit the present application. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed in the present application shall still be covered by the claims of the present application.

Claims

1. A negative pressure pneumatic conveying system for rapidly cooling powder, characterized in that: include: Powder silo, used to store high-temperature powder; Inlet air cooling unit, used to prepare cold air at a preset low temperature; A mixer, the input end pipeline of which is connected to the powder bin and the air intake cooling unit, for mixing the high-temperature powder with the cold air, and rapidly cooling the high-temperature powder by heat exchange to obtain cooled powder; A negative pressure collector, the pipeline of which is connected to the output end of the mixer, collects the cooled powder by sedimentation and filter separation, and uses the liquid-cooled dense pipes provided in the negative pressure collector to perform secondary cooling on the cooled powder to obtain low-temperature powder; The silo pump receiving port is arranged at the bottom of the negative pressure collector, and is used to monitor that when the low-temperature powder reaches a preset material level, open the ash discharge valve to connect to the silo pump receiving port and discharge the material to the outside.

2. The negative pressure pneumatic conveying system for rapidly cooling powder materials according to claim 1 is characterized in that: The upper part of the negative pressure collector is connected to a compressed air source to spray the filter material separated by sedimentation, clean the cooling powder attached to the surface of the filter material, and output clean air.

3. The negative pressure pneumatic conveying system for rapidly cooling powder materials according to claim 2 is characterized in that: Also includes: The vacuum pump and the exhaust fan of the negative pressure collector are connected in sequence by pipelines, the vacuum pump is used to provide negative pressure for the negative pressure collector, and the exhaust fan is used to discharge the clean air.

4. The negative pressure pneumatic conveying system for rapidly cooling powder materials according to claim 3 is characterized in that: Also includes: A first residual pressure valve and a second residual pressure valve, wherein the first residual pressure valve is arranged between the intake air cooling unit and the mixer, and the second residual pressure valve is arranged between the vacuum pump and the exhaust fan, so as to maintain the pressure balance between the negative pressure pneumatic conveying system and the exhaust system.

5. The negative pressure pneumatic conveying system for rapidly cooling powder materials according to claim 1 is characterized in that: Also includes: The variable frequency discharge port is arranged below the powder bin, and adaptively adjusts the discharge speed of the powder bin according to the real-time temperature of the low-temperature powder received by the negative pressure collector.

6. The negative pressure pneumatic conveying system for rapidly cooling powder materials according to claim 1, characterized in that: A fluidizing device is provided at the lower part of the negative pressure collector for uniformly outputting and cooling the temperature-reducing powder.

7. The negative pressure pneumatic conveying system for rapidly cooling powder materials according to any one of claims 1 to 6, characterized in that: The liquid-cooling close-packed pipes are provided with flowing cooling liquid.

8. The negative pressure pneumatic conveying system for rapidly cooling powder materials according to any one of claims 1 to 6, characterized in that: The pipeline is a seamless steel pipe, and the inner lining of the seamless steel pipe is a ceramic wear-resistant part.

9. A control method for a negative pressure pneumatic conveying system for rapid cooling of powder, characterized in that: include: If it is detected that the high-temperature powder stored in the powder bin reaches a preset material level threshold, the air intake cooling unit is turned on to output cold air at a preset low temperature; at the same time, the variable frequency discharger at the lower end of the powder bin is slowly opened to allow the high-temperature powder to continue to fall into the mixer; Mixing the cold air with the high-temperature powder, and rapidly cooling the high-temperature powder by heat exchange to obtain cooled powder; The cooling powder is collected by sedimentation and filter material separation, the filter material separated by sedimentation is sprayed, the cooling powder attached to the surface of the filter material is cleaned, and clean air is output; and the collected cooling powder is cooled twice by the liquid-cooled close-packed pipe in the negative pressure collector to obtain low-temperature powder; If it is monitored that the low-temperature powder in the negative pressure collector reaches a preset material level, the ash discharge valve is opened to connect to the silo pump material receiving port to discharge the material to the outside.

10. A control method for a negative pressure pneumatic conveying system for rapid cooling of powder, characterized in that: Also includes: Monitor the real-time temperature of the low-temperature powder. If the real-time temperature meets the preset temperature range, maintain the unloading speed of the powder bin and maintain the air volume of the intake air cooling unit, wherein the unloading speed of the powder and the air volume of the cold air match each other; or, if the real-time temperature is higher than the preset temperature range, reduce the unloading speed of the powder bin and / or increase the air volume of the intake air cooling unit; or, if the real-time temperature is lower than the preset temperature range, increase the unloading speed of the powder bin and / or reduce the air volume of the intake air cooling unit.

Images