Material flash drying system and method

Abstract

The present invention provides a material flash drying system and method. The system includes: a feed pipeline, a flash drying device, a filter and a gas phase circulation device; a material inlet is provided on the side wall of the flash drying device, the feed pipeline is connected to the material inlet, and the feed pipeline is provided along the tangent direction of the inner surface of the flash drying device. The method includes: allowing the product material to enter the flash drying device from the material inlet along the tangent direction of the inner surface of the flash drying device; the gas phase material obtained after flash evaporation enters the flash drying device after being processed by the filter and the gas phase circulation device; the solid phase material obtained after flash evaporation settles to the lower part of the flash drying device, and is discharged from the solid phase material outlet provided at the bottom of the flash drying device. The material flash drying system and method provided by the present invention can avoid problems such as solid phase materials sticking together to form blocks and blocking the system, and avoid the occurrence of phenomena such as solid phase materials bridging in the flash drying device.

Description

Technical Field

[0001] The invention belongs to the technical field of material drying, and in particular relates to a system and method for flash drying high-temperature and high-pressure materials. Background Art

[0002] Prior art documents CN110818892A and CN103159951A disclose a high-temperature and high-pressure polyamide material discharge technology, wherein the high-temperature and high-pressure polyamide material enters the flash drying facility from the top of the flash drying facility. At this time, the pressure is 20kg / cm 2 ~40kg / cm 2 The materials are directly discharged into the drying facility at normal pressure. In order to allow the polyamide solid phase materials to fully enter the bottom of the drying facility, the gas phase space in the drying facility needs to be designed to be large enough. A sufficiently large gas phase space can reduce the rising speed of the gas phase, so that the falling speed of the solid phase materials is higher than the rising speed of the gas phase, so that the solid phase materials can fully and effectively sink to the bottom of the flash drying facility.

[0003] The above-mentioned high temperature and high pressure polyamide material discharge technology has the following technical problems:

[0004] First, polyamide materials are usually high-temperature materials (about 200℃~300℃) before discharge. When the high-temperature materials are discharged and in a static state, they may stick to each other and form lumps locally, making it difficult for the solid phase materials to enter the next process from the flash drying facility, and even clogging the downstream facilities. If such lumps are not handled promptly and effectively, they may continue to grow and block the entire downstream facilities.

[0005] Secondly, polyamide materials are usually directly reduced from a high pressure state to a state close to normal pressure. The pressure difference caused by the direct discharge from the top of the drying facility is very large. This has a pressurized and compacted effect on the solid phase materials in the flash drying facility, making the solid phase materials more compact and more likely to form lumps or stick together. This situation will also cause the flow state of the solid phase materials to become worse when entering the downstream from the drying facility.

[0006] Finally, the polyamide material is directly reduced from a high pressure state to a state close to normal pressure. The huge pressure difference causes the unloading airflow to blow up the fine powder that has settled to the bottom of the flash drying facility. This phenomenon not only causes more fine powder to float up and enter the filter set at the top of the flash drying facility, but also the floating fine powder is easy to adhere to the inner wall of the flash drying facility, resulting in reduced operating efficiency of the flash drying facility.

[0007] Therefore, developing a new material flash drying system and method to address the above-mentioned technical problems has become one of the problems to be solved urgently in this field. Summary of the invention

[0008] In order to solve at least one of the above technical problems, the present invention provides a material flash drying system and method.

[0009] Specifically, the first aspect of the present invention provides a material flash drying system, which includes: a feed pipeline, a flash drying device, a filter and a gas phase circulation device; wherein the side wall of the flash drying device is provided with a material inlet, the top of the flash drying device is provided with a gas phase material outlet, the lower part of the flash drying device is provided with a circulating gas inlet, and the bottom of the flash drying device is provided with a solid phase material outlet; the feed pipeline is connected to the interior of the flash drying device through the material inlet, and the feed pipeline is arranged along the tangent direction of the inner surface of the flash drying device; the gas phase material outlet at the top of the flash drying device is connected to the gas phase circulation device through the filter, and the outlet of the gas phase circulation device is connected to the circulating gas inlet arranged at the lower part of the flash drying device through a pipeline.

[0010] In the above-mentioned material flash drying system, preferably, the outer wall of the feed pipeline is provided with a heat tracing and heat preservation device. More preferably, the heat tracing and heat preservation device is a heat tracing sleeve. Particularly preferably, the heat preservation medium in the heat tracing sleeve includes water or heat transfer oil, but is not limited thereto, as long as the temperature of the material can be maintained.

[0011] In the above-mentioned material flash drying system, preferably, the material inlet provided on the side wall of the flash drying device is located in the middle or upper middle part of the flash drying device.

[0012] In the above-mentioned material flash drying system, preferably, an annular baffle is provided at the lower part of the flash drying device, the annular baffle is extended from the inner wall of the flash drying device toward the central axis, and the annular baffle is vertically arranged above the circulating gas inlet of the flash drying device. More preferably, the extending direction of the annular baffle is at an angle of 15° to 60° relative to the vertical downward direction. The present invention provides an annular baffle at the lower part of the flash drying device, so that the solid phase material settled in the flash drying device does not come into contact with the circulating gas inlet at the lower part of the flash drying device, and at the same time, the gas enters the flash drying device along the lower edge of the annular baffle.

[0013] In the above-mentioned material flash drying system, preferably, the gas phase circulation device includes a blower, a circulating gas phase buffer tank, a condenser and a circulating gas dryer, the inlet of the blower is connected to the outlet of the filter, the inlet of the circulating gas phase buffer tank is connected to the outlet of the blower, the condenser is arranged at the top of the circulating gas phase buffer tank and is connected to the circulating gas phase buffer tank, the inlet of the circulating gas dryer is connected to the gas outlet of the condenser, and the outlet of the circulating gas dryer is connected to the circulating gas inlet at the lower part of the flash drying device.

[0014] In the above-mentioned material flash drying system, preferably, the gas outlet of the condenser is arranged at the top of the condenser.

[0015] In the above-mentioned material flash drying system, preferably, the inlet of the circulating gas dryer is arranged at the bottom of the circulating gas dryer, and the outlet of the circulating gas dryer is arranged at the top of the circulating gas dryer.

[0016] In the above-mentioned material flash drying system, preferably, the condenser uses cold water for condensation, a circulating water inlet is provided at the lower portion of the condenser, a circulating water outlet is provided at the upper portion of the condenser, the cold water enters from the circulating water inlet at the lower portion of the condenser, and flows out from the circulating water outlet at the upper portion of the condenser.

[0017] In the above-mentioned material flash drying system, preferably, a liquid outlet is provided at the bottom of the circulating gas phase buffer tank, for discharging the liquid phase components that enter the tank body of the circulating gas phase buffer tank after being condensed from the liquid outlet. The discharged liquid phase components can be discharged into a sewage treatment system, which can be a conventional sewage treatment system in the art, and the present invention does not specifically limit it.

[0018] According to a specific embodiment of the present invention, preferably, the material flash drying system further comprises a first supplementary gas delivery pipeline, wherein the first supplementary gas delivery pipeline is connected to a pipeline connecting the outlet of the circulating gas dryer and the circulating gas inlet at the lower part of the flash drying device.

[0019] According to a specific embodiment of the present invention, preferably, the material flash drying system further comprises a second supplementary gas delivery pipeline, and a supplementary gas inlet is further provided at the lower portion of the flash drying device, and the second supplementary gas delivery pipeline is connected to the supplementary gas inlet at the lower portion of the flash drying device. More preferably, the supplementary gas inlet is vertically provided at the lower portion of the annular baffle. Particularly preferably, the supplementary gas inlet and the circulating gas inlet are provided on the same horizontal plane of the flash drying device.

[0020] In the above-mentioned material flash drying system, preferably, an agitator is further provided inside the flash drying device, and the agitator includes a stirring and crushing device with a wall scraping function. More preferably, the stirring and crushing device with a wall scraping function includes a carrier rod, a stirring shaft, a transverse crushing paddle and a scraper; the carrier rod is transversely arranged inside the flash drying device, and both ends of the carrier rod are fixed to the inner wall of the flash drying device; the stirring shaft is installed on the carrier rod, and the stirring shaft is connected to an external motor, and the stirring shaft is driven to rotate by the external motor; the transverse crushing paddle is installed on the circumferential surface of the stirring shaft; the scraper is longitudinally installed on the outer end of the transverse crushing paddle. Among them, it is particularly preferred that the carrier rod is arranged in the middle or lower part of the interior of the flash drying device, and the carrier rod is arranged below the material inlet of the flash drying device; it is further preferred that the carrier rod is arranged above the annular baffle of the flash drying device.

[0021] If the solid-phase material sticks together or aggregates into blocks or clumps, the fluidity of the solid-phase material will deteriorate, and may even block the entire flash drying device and its solid-phase material outlet and discharge pipeline and other facilities. The present invention can set an agitator inside the flash drying device, and the agitator has a wall scraping function. The agitator has at least the following advantages: it can make the solid-phase material move slowly, play a role in dispersing the solid-phase material, and reduce the probability of sticking or agglomerating into blocks or clumps; the agitator can break up the already formed clumps during stirring, thereby maintaining the good fluidity of the solid-phase material, and at the same time reducing the possibility of the already formed clumps further increasing; after the solid-phase material enters the flash drying device many times, it may form a thin film on the inner wall of the flash drying device. If this film is not scraped off in time, it will not only affect the processing capacity of the flash drying device, but also be a waste of qualified products. Since the agitator of the present invention has a wall scraping function, it can maintain the normal operation of the flash drying device and reduce the loss of products.

[0022] In the above-mentioned material flash drying system, preferably, the bottom of the flash drying device is further provided with an inclined groove, the inclined groove has an inclined surface, the solid-phase material outlet is provided at a corresponding position in the horizontal direction of the inclined surface (the end of the inclined surface is connected to the solid-phase material outlet), and the angle of the inclined surface relative to the horizontal direction is 30° to 60°. The bottom of the flash drying device of the present invention is provided with an inclined groove and a solid-phase material outlet, and the solid-phase material falling to the inclined surface of the inclined groove can reduce the impact, so that the solid-phase material can smoothly slide out of the flash drying device from the solid-phase material outlet.

[0023] A second aspect of the present invention provides a material flash drying method, wherein the method is a method for drying a material using the above-mentioned material flash drying system, and the method comprises the following steps:

[0024] (1) Adding raw materials into the reactor to generate product materials with specified temperature and pressure;

[0025] (2) allowing the product material to enter the flash drying device from a material inlet disposed on a side wall of the flash drying device along a tangent direction of an inner surface of the flash drying device;

[0026] (3) The gaseous material obtained after the product material is flashed in the flash drying device enters the filter from the top of the flash drying device, and then enters the gas circulation device. The gaseous material discharged from the gas circulation device enters the flash drying device from the circulating gas inlet arranged at the bottom of the flash drying device;

[0027] (4) The solid phase material obtained after the product material is flashed in the flash drying device settles to the lower part of the flash drying device and is discharged from the solid phase material outlet provided at the bottom of the flash drying device.

[0028] In the above-mentioned flash drying method, preferably, the temperature of the product material is above 200°C and the pressure is 20kg / cm 2 More preferably, the temperature of the product material is 200°C to 300°C, and the pressure is 20kg / cm 2 ~40kg / cm 2 .

[0029] In the above-mentioned flash drying method, preferably, the product material comprises a polyamide material. The polyamide material generally refers to the product obtained by reacting hexamethylenediamine, adipic acid, terephthalic acid, isophthalic acid or terephthalic acid, etc. The reaction raw materials and reaction process conditions can be conventional in the art, and the present invention does not specifically limit them.

[0030] In the present invention, the product material exists as a homogeneous system before entering the flash drying device. When the product material enters the flash drying device, the system immediately changes from a homogeneous system to three phases: solid phase, gas phase and liquid phase. When the product material enters the flash drying device, the entrained liquid phase can be removed by flash evaporation or the like, so as to obtain a product containing only a small amount, a trace amount of liquid phase or basically no liquid phase in the solid phase material. For high temperature and high pressure polyamide materials, the solid phase material is usually a powdered solid of 2 to 5 mm; the gas phase material is formed after the liquid phase component in the homogeneous system is flash vaporized, and is mainly nitrogen; the liquid phase component is a substance that is not completely flash evaporated in the homogeneous system, which can be water or other liquids.

[0031] In the above-mentioned material flash drying method, preferably, the operating pressure of the flash drying device is normal pressure, and the operating temperature is normal temperature.

[0032] In the above-mentioned flash drying method for materials, preferably, the heat tracing and heat preservation device provided on the outer wall of the feed pipeline makes the temperature of the product material the same as its temperature in the reactor; more preferably, the heat tracing and heat preservation device keeps the temperature of the product material in the feed pipeline at 200°C to 300°C. The present invention provides a heat tracing and heat preservation device on the outer wall of the feed pipeline to keep the temperature of the material consistent with its temperature in the reactor in a homogeneous state, thereby reducing the formation of solid phase during the unloading process to the flash drying device of the present invention, and avoiding the phenomenon that the solid phase causes the feed pipeline, material inlet and other unloading facilities to be blocked.

[0033] In the above-mentioned material flash drying method, preferably, the gaseous material enters the flash drying device through the gas circulation device, which specifically includes: the gaseous material after filtration enters the blower to increase the pressure of the gaseous material, and the gaseous material after the pressure is increased enters the circulating gas buffer tank, and then flows into the condenser at the top of the circulating gas buffer tank, and the liquid components in the gaseous material are condensed and enter the tank body of the circulating gas buffer tank, and the gaseous material after the liquid components are separated flows out through the gas outlet of the condenser and enters the circulating gas dryer, and after being dried in the circulating gas dryer, enters the flash drying device through the circulating gas inlet arranged at the lower part of the flash drying device. More preferably, the gaseous material after filtration enters the blower to increase the pressure of the gaseous material to 4kg / cm 2 ~6kg / cm 2 .

[0034] More preferably, the method further comprises: discharging the liquid phase component in the tank body of the circulating gas phase buffer tank after being condensed from the liquid outlet at the bottom of the circulating gas phase buffer tank. The discharged liquid phase component can be discharged into a sewage treatment system. In this step, when the amount of liquid accumulated in the circulating gas phase buffer tank reaches a certain level, it can be intermittently discharged into the sewage treatment system. The sewage treatment system can be a conventional sewage treatment system in the art, and the present invention does not specifically limit it.

[0035] In the above-mentioned material flash drying method, preferably, the gas entering the flash drying device through the circulating gas inlet arranged at the lower part of the flash drying device enters along the lower edge of the annular baffle.

[0036] In the above-mentioned material flash drying method, preferably, the gas entering the flash drying device through the circulating gas inlet arranged at the lower part of the flash drying device includes nitrogen.

[0037] In the above-mentioned material flash drying method, preferably, the temperature of the gas entering the flash drying device through the circulating gas inlet arranged at the lower part of the flash drying device is 20° C. to 30° C. (normal temperature).

[0038] According to a specific embodiment of the present invention, preferably, the above-mentioned material flash drying method also includes: adding gas to the flash drying device, the supplementary gas has the same medium as the circulating gas, and the supplementary gas enters through the circulating gas inlet at the bottom of the flash drying device and / or enters through the supplementary gas inlet at the bottom of the flash drying device.

[0039] In the above-mentioned material flash drying method, preferably, the gas entering the flash drying device through the supplementary gas inlet at the lower part of the flash drying device enters along the lower edge of the annular baffle.

[0040] In the above-mentioned material flash drying method, preferably, the temperature of the gas entering the flash drying device through the supplementary gas inlet at the lower part of the flash drying device is 20° C. to 30° C. (normal temperature).

[0041] In the above-mentioned material flash drying method, preferably, the supplementary gas includes nitrogen.

[0042] In the present invention, the supplementary gas is the same medium as the circulating gas, thereby supplementing the circulating gas to make up for the gas lost during the circulation process.

[0043] According to a specific embodiment of the present invention, preferably, the above-mentioned material flash drying method may include the following steps:

[0044] (1) Adding raw materials into the reactor to generate product materials with specified temperature and pressure; the temperature of the product materials is above 200°C and the pressure is 20kg / cm 2 above;

[0045] (2) the product material is allowed to enter the flash drying device through a feed pipeline from a material inlet provided on the side wall of the flash drying device along a tangent direction of the inner surface of the flash drying device, and a heat tracing and heat preservation device is provided on the outer wall of the feed pipeline so that the temperature of the product material in the feed pipeline is the same as the temperature in the reactor, and the product material is instantly depressurized and cooled after passing through the material inlet, so that the product material is immediately formed from a homogeneous material into a solid phase material, a liquid phase component and a gas phase material obtained after flash evaporation;

[0046] (3) The gaseous material obtained after flash evaporation of the product material in the flash drying device enters the filter from the top of the flash drying device. The gaseous material obtained after flash evaporation includes a small amount or trace amount of solid material and a small amount or trace amount of liquid component. After the solid material is filtered by the filter, the filtered gaseous material enters the blower to increase the pressure of the gaseous material. After the pressure of the gaseous material is increased, it enters the circulating gas buffer tank and flows into the condenser at the top of the circulating gas buffer tank. The liquid component in the gaseous material is condensed and enters the tank body of the circulating gas buffer tank. The phase components include water and / or other liquids. The gaseous material after separation of the liquid phase components flows out through the gas outlet arranged at the top of the condenser and enters the circulating gas dryer for drying to further remove trace or trace amounts of water and / or other liquids in the gaseous material. The liquid phase components entering the tank body of the circulating gas buffer tank after condensation are discharged from the liquid outlet at the bottom of the circulating gas buffer tank and discharged into the sewage treatment system. The dried gaseous material enters the flash drying device along the lower edge of the annular baffle through the circulating gas inlet arranged at the lower part of the flash drying device;

[0047] (4) The solid phase material obtained after the product material is flashed in the flash drying device and a small amount or trace amount of liquid phase components are settled to the lower part of the flash drying device, and the solid phase material is stirred by a stirrer arranged inside the flash drying device; under the stirring of the stirrer and the gas purge entering from the circulating gas inlet of the flash drying device, and further, under the gas purge entering from the supplementary gas inlet into the flash drying device at the same time, the solid phase material slowly moves and is dried, and the solid phase material after flash drying falls to the inclined surface of the inclined trough and is discharged from the solid phase material outlet arranged at the bottom of the flash drying device.

[0048] The material flash drying system and method provided by the present invention have at least the following excellent effects.

[0049] (1) High temperature and high pressure materials, especially high temperature and high pressure polyamide materials, will form three phases during the unloading process, one is solid (i.e., solid phase material), one is liquid (i.e., liquid phase component), and the other is gaseous (i.e., gaseous phase material) generated after liquid flash evaporation. These three phases are rapidly generated by high temperature and high pressure materials after the liquid content decreases and the temperature decreases. In the present invention, a heating and heat preservation device is arranged on the outer wall of the feed pipeline of the flash drying device to keep the temperature of the material consistent with the temperature of the material in the reactor in a homogeneous state, which can reduce the formation of solid matter during the unloading process to the flash drying device and avoid the phenomenon that the solid matter causes the feed pipeline, material inlet and other unloading facilities to be blocked.

[0050] (2) The present invention moves the material discharge port from the top of the flash drying device to the middle or upper middle part of the flash drying device, and allows the material to enter the flash drying device in a tangential feeding manner. The advantages include:

[0051] Reduce the impact force on the bottom material caused by the high pressure difference when unloading from the top;

[0052] Allow the solid phase material to settle to the bottom of the flash drying device in a manner similar to cyclone separation;

[0053] This can greatly avoid the fine powder that has settled to the bottom due to high-pressure shock from floating again in the flash drying device, thereby avoiding the problem that the filter at the top of the flash drying device is easily blocked and the floating fine powder is easily adhered to the inner wall of the flash drying device, thereby avoiding the reduction of the efficiency of the flash drying device.

[0054] (3) The present invention introduces gas (mainly nitrogen) into the lower part of the flash drying device to avoid the phenomenon of solid-phase materials bridging in the flash drying device. The gas mainly plays the following four roles:

[0055] It plays the role of loosening gas; after the gas passes through the solid phase material, it slightly blows the solid phase material, which greatly reduces the possibility of the solid phase material sticking to each other or forming agglomerates locally;

[0056] It plays a role in cooling down; the gas introduced is at room temperature, so after fully contacting with the high-temperature material, it plays a role in removing the surface heat of the high-temperature material and reducing the phenomenon of mutual adhesion of the high-temperature material due to heat; in addition, if the heat of the high-temperature material is not removed in time, the material may be carbonized;

[0057] It plays a drying role; when the high-temperature and high-pressure materials are discharged into the flash drying device, they are transformed from a homogeneous liquid state into three phases: solid and liquid under normal pressure, and gaseous state generated by liquid vaporization. Among them, the solid powder (i.e., solid phase material) is generally a porous material mixed with some liquid; these liquid components will affect the product quality when the solid powder is extruded into products, so these liquid components must be removed as thoroughly as possible; in addition to using flash evaporation to remove a part of the liquid components, the present invention uses a normal temperature gas to purge the liquid components entrained in the solid powder, thereby achieving the effect of removing the liquid components in the solid powder;

[0058] The flash drying device prevents the solid phase material (ie, solid powder) from contacting with air under the protective atmosphere of gas, thereby achieving the effect of preventing the solid phase material from being oxidized by air.

[0059] (4) The present invention designs an annular baffle on the lower inner wall of the flash drying device, and the annular baffle is arranged above the gas inlet (including the circulating gas inlet and the supplementary gas inlet which may be optionally arranged) of the flash drying device. When the gas enters the flash drying device, it enters along the lower edge of the annular baffle, and the solid-phase material cannot enter the gas purging portion (i.e., the gas inlet), thereby avoiding the problem of solid-phase material blocking the gas inlet at the bottom of the flash drying device. At the same time, the design of the annular baffle enables the gas to enter the flash drying device evenly along the lower edge of the annular baffle, and can basically contact all the solid-phase materials, thereby playing a role in purging and drying.

[0060] (5) The present invention adopts a gas recycling design. The gas carrying liquid components (i.e., gas phase material) passes through a filter arranged at the top of the flash drying device, and then is pressurized by a blower and enters a circulating gas buffer tank. A condenser is arranged at the top of the circulating gas buffer tank. The cooled gas precipitates a portion of water and / or other liquids in the buffer tank, and then enters a circulating gas dryer to further remove the water and / or other liquids carried in the gas. The dried gas enters the flash drying device, thereby achieving a closed-loop recycling effect.

[0061] (6) The present invention designs an inclined trough with an inclined surface at the bottom of the flash drying device. The solid phase material falls through the buffer of the inclined trough and reaches the solid phase material outlet, so that the solid phase material can be completely and smoothly moved out of the flash drying device.

[0062] Therefore, the material flash drying system and method provided by the present invention have good industrial value and broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 It is a schematic structural diagram of a material flash drying system provided in one specific embodiment of the present invention.

[0064] Figure 2 It is a schematic structural diagram of a tangential feed pipeline and a tangential feed port in a material flash drying system provided in a specific embodiment of the present invention.

[0065] Description of reference numerals:

[0066] 1: reactor, 2: tangential feed line, 3: flash drying device, 4: tangential feed port, 5: filter, 6: blower, 7: circulating gas buffer tank, 8: condenser, 9: circulating gas dryer, 10: agitator, 11: inclined trough, 111: solid phase material outlet, 112: inclined surface, 12: circulating gas inlet, 13: supplementary gas inlet, 14: first supplementary gas delivery pipeline, 15: second supplementary gas delivery pipeline, 16: annular baffle, 101: carrier rod, 102: stirring shaft, 103: transverse crushing paddle, 104: scraper, M: motor. DETAILED DESCRIPTION

[0067] In order to have a clearer understanding of the technical features, purposes and beneficial effects of the present invention, the technical solution of the present invention is now described in detail below, but it should not be construed as limiting the applicable scope of the present invention.

[0068] Example 1

[0069] This embodiment provides a material flash drying system, such as Figure 1 As shown, the system includes: a tangential feed pipeline 2, a flash drying device 3, a filter 5 and a gas phase circulation device.

[0070] It should be noted that Figure 1 The reactor 1 is also shown. In this embodiment, the reactor 1 is a high-temperature reactor for preparing polyamide, but is not limited thereto. The reactor 1 can be a high-pressure reactor, a catalytic reactor, a polymerization reactor, etc., and any high-temperature and high-pressure reaction device commonly used in the prior art can be used.

[0071] The side wall of the flash drying device 3 is provided with a tangential feed port 4, the top of the flash drying device 3 is provided with a gas phase material outlet, the lower part of the flash drying device is provided with a circulating gas inlet 12 and a supplementary gas inlet 13, and the bottom of the flash drying device 3 is provided with an inclined groove 11 and a solid phase material outlet 111.

[0072] like Figure 1 As shown, the tangential feed port 4 is located in the middle of the flash drying device 3. Figure 2 As shown, the tangential feed pipeline 2 is connected to the flash drying device 3 through the tangential feed port 4, and the tangential feed pipeline 2 is arranged along the tangential direction of the inner surface of the flash drying device 3.

[0073] A heating sleeve is provided on the outer wall of the tangential feed pipeline 2. The heat-insulating medium in the heating sleeve can be water or heat-conducting oil, but is not limited thereto, as long as the temperature of the material can be maintained.

[0074] An annular baffle 16 is provided at the lower part of the flash drying device 3. The annular baffle 16 extends from the inner wall of the flash drying device 3 toward the central axis of the device. The extending direction of the annular baffle 16 forms an angle of 45° with respect to the vertical downward direction, and the annular baffle 16 is vertically arranged above the circulating gas inlet 12 and the supplementary gas inlet 13 of the flash drying device 3.

[0075] The inlet of the filter 5 is connected to the gas phase material outlet at the top of the flash drying device 3 .

[0076] The gas phase circulation device includes a blower 6, a circulating gas phase buffer tank 7, a condenser 8, and a circulating gas dryer 9. The inlet of the blower 6 is connected to the outlet of the filter 5 through a pipeline, the inlet of the circulating gas phase buffer tank 7 is connected to the outlet of the blower 6 through a pipeline, the condenser 8 is arranged at the top of the circulating gas phase buffer tank 7 and is communicated with the circulating gas phase buffer tank 7, the inlet at the bottom of the circulating gas dryer 9 is connected to the gas outlet at the top of the condenser 8 through a pipeline, and the outlet at the top of the circulating gas dryer 9 is connected to the circulating gas inlet 12 at the bottom of the flash drying device 3 through a pipeline;

[0077] The condenser 8 uses cold water for condensation. A circulating water inlet is provided at the lower part of the condenser 8, and a circulating water outlet is provided at the upper part of the condenser 8. The cold water enters from the circulating water inlet at the lower part of the condenser 8 and flows out from the circulating water outlet at the upper part of the condenser 8.

[0078] A liquid outlet is provided at the bottom of the circulating gas phase buffer tank 7, which is used to discharge the liquid components that enter the tank body of the circulating gas phase buffer tank 7 after condensation from the liquid outlet and discharge them into the sewage treatment system.

[0079] The system also includes a first supplementary gas delivery pipeline 14 and a second supplementary gas delivery pipeline 15; the first supplementary gas delivery pipeline 14 is connected to the outlet of the circulating gas dryer 9 and the circulating gas inlet 12 at the bottom of the flash drying device 3; the second supplementary gas delivery pipeline 15 is connected to the supplementary gas inlet 13 at the bottom of the flash drying device 3; and the supplementary gas inlet 13 and the circulating gas inlet 12 are arranged on the same horizontal plane of the flash drying device 3; the supplementary gas and the circulating gas have the same medium.

[0080] The interior of the flash drying device 3 may be further provided with an agitator 10, which may be a stirring and crushing device with a wall scraping function, and the stirring and crushing device with a wall scraping function includes a carrier rod 101, a stirring shaft 102, a transverse crushing paddle 103 and a scraper 104; when viewed from the vertical direction, the carrier rod 101 is transversely arranged at the lower part of the interior of the flash drying device 3, the carrier rod 101 is arranged below the tangential feed port 4 and above the annular baffle 16, and both ends of the carrier rod 101 are fixed to the inner wall of the flash drying device 3; the stirring shaft 102 is installed on the carrier rod 101, and the stirring shaft 102 is connected to the external motor M, and the stirring shaft 102 is driven to rotate by the external motor M; the transverse crushing paddle 103 is installed on the circumferential surface of the stirring shaft 102; the scraper 104 is longitudinally installed on the outer end of the transverse crushing paddle 103.

[0081] An inclined groove 11 and a solid-phase material outlet 111 are provided at the bottom of the flash drying device 3. The inclined groove 11 has an inclined surface 112, and the angle of the inclined surface 112 relative to the horizontal direction is 45°. The solid-phase material outlet 111 is arranged at a corresponding position in the horizontal direction of the inclined surface 112. The solid-phase material falls through the buffer of the inclined groove 11 and reaches the solid-phase material outlet 111.

[0082] Example 2

[0083] This embodiment provides a material flash drying method, which is a method of drying the material using the material flash drying system provided in Example 1. The method comprises the following steps:

[0084] (1) Adding raw materials into the reactor 1 to generate product materials with specified temperature and pressure; the temperature of the product materials is 200°C to 300°C, and the pressure is 20kg / cm 2 ~40kg / cm 2 ; The product material is polyamide material;

[0085] (2) the product material is allowed to enter the flash drying device 3 through the tangential feed line 2 and the tangential feed port 4 provided on the side wall of the flash drying device 3 along the tangential direction of the inner surface of the flash drying device 3, and the outer wall of the tangential feed line 2 is provided with a heating sleeve so that the temperature of the product material in the tangential feed line 2 is the same as the temperature in the reactor 1, and the product material is instantly depressurized to normal pressure and cooled to normal temperature after passing through the tangential feed port 4, so that the product material is immediately formed from a homogeneous material into a solid phase material, a liquid phase component and a gas phase material obtained after flash evaporation;

[0086] (3) The gaseous material obtained after flash evaporation of the product material in the flash drying device 3 enters the filter 5 from the top of the flash drying device 3. The gaseous material obtained after flash evaporation includes a small amount or trace amount of solid phase material and a small amount or trace amount of liquid phase component. After the solid phase material is filtered by the filter 5, the filtered gaseous material enters the blower 6 to increase the pressure of the gaseous material to 4 kg / cm 2 ~6kg / cm 2 After about 10 seconds, the gaseous material with increased pressure enters the circulating gas buffer tank 7 and flows into the condenser 8 at the top of the circulating gas buffer tank 7. The liquid components in the gaseous material are condensed and enter the tank body of the circulating gas buffer tank 7. The liquid components include water and / or other liquids. The gaseous material after separation of the liquid components flows out through the gas outlet arranged at the top of the condenser 8 and enters the circulating gas dryer 9 for drying to further remove trace or trace amounts of water and / or other liquids in the gaseous material. The liquid components in the tank body of the circulating gas buffer tank 7 after condensation are discharged from the liquid outlet at the bottom of the circulating gas buffer tank 7 and discharged into the sewage treatment system. The gaseous material after drying enters the flash drying device 3 along the lower edge of the annular baffle 16 through the circulating gas inlet 12 arranged at the lower part of the flash drying device 3. The temperature of the circulating gas entering the flash drying device 3 through the circulating gas inlet 12 is 20°C to 30°C (normal temperature). At the same time, the gas is supplemented through the supplementary gas inlet 13 and the second supplementary gas delivery pipeline 15 at the lower part of the flash drying device 3, and the gas is supplemented through the first supplementary gas delivery pipeline 14. The medium of the supplementary gas and the circulating gas is the same, both are nitrogen, and the temperature of the supplementary gas is also 20°C to 30°C (normal temperature). The supplementary gas also enters the flash drying device 3 along the lower edge of the annular baffle 16.

[0087] (4) The solid phase material obtained after flash evaporation of the product material in the flash drying device 3 and a small amount or trace amount of liquid phase components are settled to the lower part of the flash drying device 3, and the solid phase material is stirred by the stirrer 10 arranged inside the flash drying device 3; under the stirring of the stirrer 10 and the purge of the gas (i.e., circulating gas and supplementary gas) of the flash drying device 3, the solid phase material slowly moves and is dried, and the solid phase material after flash drying falls to the inclined surface 112 of the inclined trough 11, and is discharged from the solid phase material outlet 111 arranged at the bottom of the flash drying device 3.

Claims

1. A material flash drying system, the system comprising: The feed pipeline, the flash drying device, the filter and the gas phase circulation device are characterized in that: The side wall of the flash drying device is provided with a material inlet, the material inlet is located in the middle or upper middle part of the flash drying device, the top of the flash drying device is provided with a gas phase material outlet, the lower part of the flash drying device is provided with a circulating gas inlet, and the bottom of the flash drying device is provided with a solid phase material outlet; The feed pipeline is connected to the interior of the flash drying device through the material inlet, and the feed pipeline is arranged along the tangent direction of the inner surface of the flash drying device; the outer wall of the feed pipeline is provided with a heat tracing and heat preservation device; An annular baffle is provided at the lower part of the flash drying device, the annular baffle is extended from the inner wall of the flash drying device to the central axis, and the annular baffle is arranged at the upper part of the circulating gas inlet of the flash drying device in the vertical direction, and the extending direction of the annular baffle forms an angle of 15° to 60° relative to the vertical downward direction; The bottom of the flash drying device is further provided with an inclined groove, the inclined groove has an inclined surface, the solid phase material outlet is arranged at a corresponding position in the horizontal direction of the inclined surface, and the angle of the inclined surface relative to the horizontal direction is 30° to 60°; The gas phase material outlet at the top of the flash drying device is connected to the gas phase circulation device through the filter, and the outlet of the gas phase circulation device is connected to the circulating gas inlet arranged at the bottom of the flash drying device through a pipeline.

2. The material flash drying system according to claim 1, characterized in that: The heating and heat preservation device is a heating sleeve.

3. The material flash drying system according to claim 2, characterized in that: The heat-insulating medium in the heating sleeve includes water or heat-conducting oil.

4. The material flash drying system according to claim 1, characterized in that: The gas phase circulation device includes a blower, a circulating gas phase buffer tank, a condenser and a circulating gas dryer. The inlet of the blower is connected to the outlet of the filter, the inlet of the circulating gas phase buffer tank is connected to the outlet of the blower, the condenser is arranged on the top of the circulating gas phase buffer tank and is communicated with the circulating gas phase buffer tank, the inlet of the circulating gas dryer is connected to the gas outlet of the condenser, and the outlet of the circulating gas dryer is connected to the circulating gas inlet at the lower part of the flash drying device.

5. The material flash drying system according to claim 4, characterized in that: The condenser uses cold water for condensation. A circulating water inlet is provided at the lower part of the condenser, and a circulating water outlet is provided at the upper part of the condenser. The cold water enters from the circulating water inlet at the lower part of the condenser and flows out from the circulating water outlet at the upper part of the condenser.

6. The material flash drying system according to claim 4, characterized in that: The bottom of the circulating gas phase buffer tank is provided with a liquid outlet for discharging the liquid components entering the tank body of the circulating gas phase buffer tank after being condensed through the liquid outlet.

7. The material flash drying system according to claim 4, characterized in that: The material flash drying system further comprises a first supplementary gas delivery pipeline, which is connected to a pipeline connecting an outlet of the circulating gas dryer and a circulating gas inlet at a lower portion of the flash drying device.

8. The material flash drying system according to claim 1, characterized in that: The material flash drying system also includes a second supplementary gas delivery pipeline, and a supplementary gas inlet is also provided at the lower part of the flash drying device, the second supplementary gas delivery pipeline is connected to the supplementary gas inlet at the lower part of the flash drying device, and the supplementary gas inlet is vertically arranged at the lower part of the annular baffle.

9. A material flash drying method, characterized in that: A method for drying a material using the material flash drying system described in any one of claims 1 to 8, the method comprising the following steps: (1) Adding raw materials into the reactor to generate product materials with specified temperature and pressure; (2) the product material enters the flash drying device from a material inlet disposed on the side wall of the flash drying device along a tangent direction of the inner surface of the flash drying device, and a heat tracing and heat preservation device disposed on the outer wall of the feed pipeline makes the temperature of the product material the same as the temperature in the reactor; (3) The gaseous material obtained after the product material is flashed in the flash drying device enters the filter from the top of the flash drying device, and then enters the gas circulation device. The gaseous material discharged from the gas circulation device then enters the flash drying device from the circulating gas inlet arranged at the lower part of the flash drying device along the lower edge of the annular baffle; (4) The solid phase material obtained after the product material is flashed in the flash drying device settles to the lower part of the flash drying device and is discharged from the solid phase material outlet provided at the bottom of the flash drying device.

10. The material flash drying method according to claim 9, characterized in that: The product material temperature is above 200°C and the pressure is 20kg / cm 2 above.

11. The material flash drying method according to claim 10, characterized in that: The temperature of the product material is 200℃~300℃, and the pressure is 20kg / cm 2 ~40kg / cm 2 .

12. The material flash drying method according to claim 9, characterized in that: The product material includes a polyamide material.

13. The material flash drying method according to claim 9, characterized in that: The operating pressure of the flash drying device is normal pressure, and the operating temperature is normal temperature.

14. The material flash drying method according to claim 9, characterized in that: The heating and heat preservation device keeps the temperature of the product material in the feed pipeline at 200°C to 300°C.

15. The material flash drying method according to claim 9, characterized in that: The gaseous material enters the flash drying device through the gas circulation device, specifically including: the filtered gaseous material enters the blower to increase the pressure of the gaseous material, the gaseous material after the pressure is increased enters the circulating gas buffer tank, and then flows into the condenser at the top of the circulating gas buffer tank, the liquid components in the gaseous material are condensed and enter the tank body of the circulating gas buffer tank, the gaseous material after the liquid components are separated flows out through the gas outlet of the condenser and enters the circulating gas dryer, after being dried in the circulating gas dryer, enters the flash drying device through the circulating gas inlet arranged at the lower part of the flash drying device.

16. The material flash drying method according to claim 15, characterized in that: The filtered gaseous material enters the blower to increase the pressure of the gaseous material to 4 kg / cm 2 ~6kg / cm 2 .

17. The material flash drying method according to claim 9, characterized in that: The gas entering the flash drying device through the circulating gas inlet arranged at the lower part of the flash drying device includes nitrogen.

18. The material flash drying method according to claim 9, characterized in that: The temperature of the gas entering the flash drying device through the circulating gas inlet arranged at the lower part of the flash drying device is 20°C to 30°C.

19. The material flash drying method according to claim 9, characterized in that: The material flash drying method also includes: supplementing gas into the flash drying device, wherein the supplementary gas has the same medium as the circulating gas, the supplementary gas enters through the circulating gas inlet at the bottom of the flash drying device and / or enters through the supplementary gas inlet at the bottom of the flash drying device, and the gas entering the flash drying device through the supplementary gas inlet at the bottom of the flash drying device enters along the lower edge of the annular baffle.

20. The material flash drying method according to claim 19, characterized in that: The supplemental gas includes nitrogen.

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