A drying and cooling integrated machine and a drying and cooling method

Abstract

The present invention belongs to the field of powder material processing, and specifically relates to a drying and cooling integrated machine and a drying and cooling method. The present invention arranges a fluidized drying section, a fluidized cooling section and a gravity cooling section from top to bottom in the shell body, so that the materials in the fluidized drying section and the fluidized cooling section are in a fluidized state, so that the materials fed from the feed port are quickly spread in the horizontal direction, and a uniform particle distribution is formed in the cross section of the shell body, so that the materials pass through the gravity cooling section uniformly and as a whole, eliminating the material segregation and the uneven cooling caused by the different cooling speeds of the materials in different places; the high heat and mass transfer rate brought by the fluidization of the materials is used to efficiently dry the materials in the drying section; the hot and humid gas can be effectively replaced in the fluidized cooling section to avoid the scarring of the materials. After the materials after fluidized drying, cooling and dry gas replacement enter the gravity cooling section, they can be cooled by a refrigerant with a lower temperature, while improving the cooling efficiency and cooling effect.

Description

Technical Field

[0001] The invention relates to the field of powder material processing, and in particular to a drying and cooling integrated machine and a drying and cooling method. Background Art

[0002] Obtaining products through microbial fermentation is one of the main production methods in the biochemical industry. Due to the complex composition of the fermentation broth, which contains a variety of organic and inorganic metabolites, various impurities are inevitably present in the main and by-products obtained from the post-processing of the crude fermentation broth, resulting in adhesion and hardening of the products during storage and transportation, reducing product quality and increasing transportation and fertilization costs. Crystallized products produced by fermentation often contain crystal water, which has poor stability when under pressure or heat, or has hygroscopic properties. Therefore, when stored for a long time, the particles will fuse with each other, which is also prone to cause the same problem.

[0003] Generally speaking, the powder and granular products of fermentation plants need to be dried in different forms of dryers to reach the qualified moisture content, and then cooled to near room temperature by cooling equipment such as fluidized bed and rotary drum before packaging and shipment. However, for cooling equipment such as fluidized bed and rotary drum, since the air is in direct contact with the material, moisture will also enter the material from the air while the material is being cooled; or because the material cooling process is not thorough, heat and moisture will still migrate between the inside and surface of the material particles, and between the surface of the particles and the air in the surrounding gaps after cooling, which will eventually lead to agglomeration and compaction. In order to avoid product agglomeration, the current tendency is to reduce the moisture content of the product to a level far below the equilibrium moisture content under ambient conditions during the drying process. Based on the fact that fermented products are prone to moisture absorption, ambient air, especially ambient air in hot and humid seasons, is used as a refrigerant. While the material is being cooled, moisture in the air will also enter the material, causing the material to absorb moisture. There are certain gaps between the particles of the bulk material. The humid air filling the gaps enters the closed environment of the packaging bag. The moisture absorption process on the surface of the particles will also cause further adhesion of the particles. If the temperature of the packaged material is higher than the ambient temperature, the moisture inside the particles will continue to migrate to the surface and be released into the gaps during the process of the material continuing to dissipate heat to the environment, which will continue to increase the humidity of the air and cause adhesion between the particles. Therefore, for equipment where materials are directly contacted with air for cooling, it is necessary to deeply dehumidify the air to prevent the materials from absorbing moisture during the cooling process, and replace the air in the gaps between the material particles with dry air; due to the efficiency of the cooling equipment, in order to cool the materials to the ambient temperature (for example, to cool the materials to below 25-35°C in summer), a lower inlet air temperature and a lower relative humidity at the inlet air temperature are required (for example: dry bulb temperature 20°C, relative humidity 20%), but the air is humid in summer and autumn, and the energy consumption of the dehumidification and cooling process is relatively large, sometimes even accounting for more than 20-30% of the energy consumption of the drying process. In addition, during the cooling process, the particles are in a state of violent motion, and the friction between the particles and between the particles and the wall of the cooling equipment will cause the particles to wear, and the friction will generate new dust that enters the product, reducing the product quality and increasing the degree of product agglomeration.

[0004] In recent years, the fertilizer industry, especially the urea industry, has begun to introduce cooling devices for indirect heat transfer of bulk solid materials from the international market. Compared with fluidized bed coolers, they have obvious technical advantages in energy saving, emission reduction, cooling depth, etc. The main body of this cooling device is a vertically arranged container, which is divided into three parts from top to bottom: feeding section, cooling section and discharging section. The cooling section is equipped with a heat exchanger; free-flowing solid particles enter the container from the inlet of the feeding section and move slowly from top to bottom under the action of gravity. When flowing through the cooling section, they flow through the external channel of the heat exchanger set in this part. The heat is taken away by the refrigerant in the heat exchanger and the material is cooled to the required temperature, and then enters the shell of the discharging section and is discharged from its outlet. Since the material is in a slow overall flow state during the cooling process, the friction between particles and between particles and the wall surface is very small, and particle wear is basically eliminated. And because it is an indirect heat transfer method, the material is basically not in contact with the air, which avoids the increase of the water content of the product during the cooling process.

[0005] However, when processing powdered and granular products in fermentation plants, whether they are crystalline products or granular products made by granulating and drying a mixed liquid with multiple ingredients, there are some common problems when using gravity flow coolers for cooling:

[0006] (1) After the material absorbs moisture, it is easy to form scars on the heat exchange wall of the heat exchanger, especially the wall of the heat exchanger located above the gravity flow cooler, which will cause a significant decrease in the heat exchange effect. In severe cases, it will also cause partial blockage of the material flow channel. In addition, the material itself will also form lumps after absorbing moisture.

[0007] (2) In a gravity flow cooler, it is always expected that the material flows downward at a uniform speed over the entire cross section of the cooler, that is, moves downward in the so-called overall flow, so as to obtain the best cooling effect. However, the actual application is not always so ideal, especially for materials that are easy to absorb moisture, agglomerate, and scab. The agglomeration and scab of the material aggravate the unevenness of the overall flow of the material, making the degree of cooling of the material in different areas on different cross sections of the cooling equipment more different. This leads to some materials still having high temperatures. Even if the average discharge temperature meets the requirements, these materials may still become hardened during long-term storage.

[0008] The above problems restrict the application and promotion of gravity flow coolers in the fermentation industry or industries with similar material characteristics, making it impossible for them to replace traditional mature direct contact cooling devices such as fluidized beds and rotary drums.

[0009] Chinese patent document CN110701927A (201910776877.2) discloses a material cooling system based on a powder flow cooler. Although the above-mentioned material cooling system can effectively avoid the scarring of the wall of the powder flow cooler and the agglomeration of the material during the cooling process, since the above-mentioned material cooling system needs to increase the temperature of the coolant in the powder flow cooler to reduce the temperature difference between the coolant and the material in the powder flow cooler, the temperature of the coolant must be greater than the dew point value of the material. However, the material after drying is usually still at a relatively high temperature, and it is impossible to use a coolant at a lower temperature to cool the material, resulting in a decrease in the overall cooling efficiency. In addition, the dry air introduced into the material cooling system will gather upward after absorbing the moisture in the material, and the material fed into the material cooling system contains a large amount of hot and humid gas, which makes the upper material at the top of the material cooling system have a relatively high humidity. In order to avoid scarring, it is necessary to further increase the entry temperature of the coolant in the upper powder flow cooler, resulting in a further decrease in the overall cooling efficiency.

[0010] In addition, during the drying and cooling process of powder materials, the materials are generally dried by drying equipment first and then enter the cooling section for cooling treatment. Drying and cooling are completed in different equipment respectively, which not only brings higher energy consumption, but also occupies a large area of ​​equipment, increasing investment costs.

[0011] Chinese patent document CN104132525A (201410397432.0) discloses an integrated drying and cooling device for powder materials. The device is a vertical structure, which includes a feed box, a drying box, a cooling box and a discharge box from top to bottom. It can realize the drying and cooling requirements of powder materials in heat exchange plates, and has the advantages of small footprint and high heat exchange efficiency. However, its disadvantage is that the cross-flow air used for drying passes through the material layer in the horizontal direction. When the flow rate of the cross-flow gas is large, the resistance of the airflow passing through the material layer increases sharply, and the material flows after being squeezed. Deterioration in performance makes it more likely to cause local blockage; since the drying box and the cooling box are interconnected, the hot and humid gas between the materials will enter the cooling box along with the hot materials. In order to prevent the materials from forming scars on the heat exchange plates in the cooling box, the materials must be dried to a certain depth, or the temperature of the cooling water must be increased to reduce the heat transfer temperature difference between the materials and the cooling water. The above problems limit the equipment capacity and stable operation, or the height of the drying box or cooling box must be increased to increase the equipment capacity or ensure the normal operation of the equipment without scarring, resulting in an increase in equipment investment, feeding costs, or the need for a higher factory building. Summary of the invention

[0012] The main purpose of the present invention is to provide a drying and cooling integrated machine and a drying and cooling method. The present invention arranges a fluidized drying section, a fluidized cooling section and a gravity cooling section from top to bottom in a shell body, and introduces gas into the shell body through a first fluidized air gas distribution component in the fluidized drying section (and adds the gas introduced from the fluidized cooling section), so that the material above the first fluidized air gas distribution component is in a fluidized state, so that the material fed from the feed port is quickly spread in the horizontal direction and forms a uniform particle distribution on the cross section of the shell body, eliminating the material segregation phenomenon, so that the material moves downward uniformly as a whole through the fluidized cooling section; utilizing the high heat and mass transfer rate brought by the fluidization of the material, the material is dried or deeply dried under the heating of the drying heat exchanger component and the hot air, thereby improving the drying efficiency of the material. In the fluidized cooling section, dry gas is introduced into the shell body through the second fluidized air gas distribution component, so that the material above the second gas distribution component is in a fluidized state, avoiding the material from scarring on the surface of the cooling heat exchanger component; the high heat and mass transfer rate brought by the fluidization of the material and the sufficient mixing and contact between the particles and the gas can further remove the humid hot gas brought into the material during the drying process of the fluidized drying section and the moisture in the material particles, ensuring that the material is cooled more evenly and the moisture content of the material is more uniform everywhere. After the material with uniform particle size distribution and uniform moisture content in the dry gas environment enters the gravity cooling section, it passes through the gravity cooling section in the form of a whole flow, which is conducive to the cooling heat exchanger component using a lower temperature refrigerant to cool the material, reducing the unevenness of the cooling process, and improving the cooling efficiency and cooling effect.

[0013] The technical problem to be solved by the present invention is achieved by adopting the following technical solution: a drying and cooling integrated machine, comprising a shell body, a drying heat exchanger assembly, a cooling heat exchanger assembly, a gas distribution assembly, a gas supply system and a heat exchange medium supply system;

[0014] The drying heat exchanger assembly and the cooling heat exchanger assembly are plate heat exchangers or tube heat exchangers, and a first material channel penetrating up and down is provided between the heat exchange plates or between the heat exchange tubes of the drying heat exchanger assembly and the cooling heat exchanger assembly;

[0015] The gas distribution assembly comprises an air distribution channel distributed along the cross section of the shell body, second material channels are arranged outside the air distribution channel and are distributed along the cross section of the shell body at intervals, and the side wall of the air distribution channel is provided with air distribution holes communicating with the inner cavity of the shell body;

[0016] The shell body is a vertical shell, the top of the shell body is provided with a feed inlet and an exhaust port, and the bottom of the shell body is provided with a discharge port;

[0017] The shell body is provided with a fluidized drying section, a fluidized cooling section and a gravity cooling section from top to bottom;

[0018] The fluidized drying section is provided with a drying heat exchanger assembly connected to a heat exchange medium supply system;

[0019] The fluidized cooling section and the gravity cooling section are provided with a cooling heat exchanger assembly connected to a heat exchange medium supply system;

[0020] The heat exchange medium supply system is used to provide heat medium and cold medium to the drying heat exchanger assembly and the cooling heat exchanger assembly respectively;

[0021] The gas distribution assembly comprises a first fluidizing air gas distribution assembly and a second fluidizing air gas distribution assembly respectively arranged in the fluidizing drying section and the fluidizing cooling section, wherein the first fluidizing air gas distribution assembly and the second fluidizing air gas distribution assembly are respectively connected to the gas supply system;

[0022] The first fluidizing air gas distribution component is used to introduce hot dry gas or hot gas that has not been dehumidified by the gas dehumidification equipment into the shell body, and its ventilation volume simultaneously merges with the ventilation volume of the second fluidizing air gas distribution component, so that the material in the fluidized drying section is fluidized, and the material entering the fluidized drying section is quickly spread in the horizontal direction, thereby eliminating the feed cone and the accompanying feed segregation problem, ensuring that the material particle size of the fluidized drying section enters the fluidized cooling section with uniform distribution; the material layer in the fluidized state has a higher drying efficiency or a lower final moisture content than the slowly moving material layer in the aerated state; when hot dry gas is used, the mass transfer driving force can be further increased and more moisture can be carried, thereby further reducing the final moisture content;

[0023] The second fluidizing air gas distribution component is used to introduce dry gas into the shell body to make the material in the fluidized cooling section fluidized. Similarly, based on the high heat / mass transfer rate brought by fluidization and the sufficient mixing and contact between the particles and the gas, when using dry gas, the moist and hot gas in the gaps between the material particles can be more effectively removed, so that the replaced material is in a uniform dry gas environment, and the dew point temperature is much lower than the temperature of the refrigerant in the cooling heat exchanger component. Therefore, a lower temperature refrigerant can be used to cool the material to improve the cooling efficiency; the high mass transfer rate in the fluidized state can also replace the gas in the air pockets and pores on the surface of the particles to a certain extent, so that the moisture in the material can be further removed, thereby playing a role in further deep drying.

[0024] In the present invention, the gas introduced into the first fluidized air gas distribution component is hot dry gas or non-dehumidified hot gas; in the drying stage, a large amount of water in the material evaporates into the gas, and both the material and the gas are in a high-temperature state, far away from the equilibrium moisture between the material and the gas. Therefore, from the perspective of energy saving, it is common to use non-dehumidified gas to dry the material.

[0025] The dry gas introduced into the second fluidizing air gas distribution component includes dry cold gas, room temperature dry gas or dry gas whose temperature is lower than the material temperature when the material leaves the fluidizing cooling section; dry cold gas is preferred, which has the effect of cooling the material while performing dry gas replacement, thereby further improving the cooling efficiency.

[0026] Preferably, in the present invention, when the first fluidizing wind gas distribution assembly and the second fluidizing wind gas distribution assembly are working simultaneously, the fluidizing wind speed generated by the ventilation volume of the second fluidizing wind gas distribution assembly is not less than 1 times the critical fluidizing speed calculated according to the average particle size of the material (that is, the fluidization number is 1); the fluidizing wind speed generated by the sum of the ventilation volumes of the first fluidizing wind gas distribution assembly and the second fluidizing wind gas distribution assembly is not less than 1.5 times the critical fluidizing speed calculated according to the average particle size of the material (that is, the fluidization number is 1.5); the fluidizing wind speed generated by the sum of the ventilation volumes of the first fluidizing wind gas distribution assembly and the second fluidizing wind gas distribution assembly is not higher than 15 times the critical fluidizing speed calculated according to the average particle size of the material (that is, the fluidization number is 15).

[0027] The above-mentioned fluidizing wind speed refers to the operating wind speed when the material is in a fluidized state (that is, the actual value of the wind speed during production operation), which is the average operating wind speed through the cross section calculated according to the horizontal net cross-sectional area of ​​the shell body; the fluidization number refers to the ratio of the fluidizing wind speed (the operating wind speed when the fluidized state is not reached) to the critical fluidizing velocity calculated according to the average particle size of the material.

[0028] When the second fluidized air gas distribution component is working, the fluidized air velocity of the material in the fluidized cooling section is greater than the fluidization number 1, so that the material is in a fully and uniform fluidized state, and the moisture vapor contained in the gas in the gaps of the material is taken out to avoid the blockage of the material flow in local areas. When the second fluidized air gas distribution component is ventilated, the gas rises and passes through the fluidized cooling section and then enters the fluidized drying section. The fluidized air velocity generated by the sum of the ventilation volume after merging with the ventilation of the first fluidized air gas distribution component is not less than the fluidization number 1.5, forming a more intense fluidization than the fluidized cooling section, which is conducive to quickly eliminating the feed cone, making the material particle size distribution uniform, and providing sufficient air volume to quickly discharge the moisture generated during the drying process and avoid the exhaust gas humidity reaching a saturated state, causing problems such as scarring and agglomeration; the heat increases accordingly with the increase in air volume, which is conducive to improving the drying efficiency. The fluidization wind speed of the material in the fluidized drying section should not exceed the fluidization number 15, because the upper limit of the fluidization wind speed is the maximum wind speed that maintains stable fluidization of the material layer without excessive entrainment. It can be considered with reference to the upper limit of the operating gas speed of the normal fluidized bed.

[0029] From the perspective of making the material fluidized and flowing to eliminate the feed cone, this can be achieved within a certain range of operating wind speed from low to high close to the critical fluidization speed (for example, for a 70% lysine granulation product, the feed cone can be basically eliminated when the operating wind speed is at a fluidization number of 0.7 to 1). However, this local and insufficient fluidization cannot meet the requirements of this patent. Because in the equipment involved in this patent, when the operating air velocity is determined according to the average particle size, for materials with a wide particle size distribution, when the fluidization number is below 1 but close to 1, a small part of the material below the average particle size is already in a bubbling fluidized state, while the particles with larger particle sizes are still in a static state. This local fluidized area is randomly scattered on the entire cross-section of the box; in the material cone area above the material layer, due to the driving of the rising bubbles and the flowing particles, the feed cone can be basically eliminated under the action of the gravity of the material pile itself, achieving the purpose of making the bed tend to be basically horizontal; however, due to the air flow short circuit caused by this so-called "local fluidization" or "semi-fluidization", local material flow blockage, and uneven distribution of air holes (only distributed at the gas distribution pipe, and the gas distribution pipes are material flow channels) and other reasons, the humid air in the material in the non-fluidized area is more difficult to discharge; the existence of the moisture absorption and agglomeration characteristics of the material makes the material in the static state in the non-fluidized area more prone to moisture absorption, agglomeration or scarring. Therefore, in the present invention, it is not advisable to have an operating air velocity lower than the fluidization number 1.

[0030] Furthermore, the fluidized cooling section and the gravity cooling section are provided with two or more layers of cooling heat exchanger components from top to bottom, each layer of cooling heat exchanger components forms a cooling section, and the temperature of the refrigerant of each layer of cooling heat exchanger components decreases from top to bottom. Two or more layers of cooling heat exchanger components are provided from top to bottom in the fluidized cooling section and the gravity cooling section to provide refrigerants of different temperatures for different cooling sections, and the technical significance is as follows:

[0031] a. Powdered and granular materials generally contain a small amount of moisture and have a certain degree of hygroscopicity. Under equilibrium conditions, materials at a certain temperature correspond to a certain critical relative moisture content of the gas in the gap between particles and the corresponding critical dew point temperature. When the relative moisture content value or dew point temperature of the gas is higher than the critical value, the moisture will migrate from the gas to the material, and the material will absorb moisture. In the gravity cooling section, the material layer can be regarded as a fixed bed that moves slowly along a fixed flow channel in an aerated state. As the material moves downward, the material temperature gradually decreases, and the corresponding critical relative moisture content value and critical dew point value gradually decrease. The material at the end (lower end) of different cooling sections is cooled to a certain temperature, which requires that the refrigerant temperature of each cooling section must be higher than a certain equilibrium temperature corresponding to the material at the end (lower end) to ensure that the relative moisture content and dew point temperature of the gas environment around the particles are lower than the critical value to avoid moisture absorption by the material. However, in the fluidized cooling section, due to the violent backmixing of the material in the upward and downward directions, the temperature difference of the material along the bed height direction is reduced to a value within a certain range below the average temperature of the material (but higher than the equilibrium temperature corresponding to the end of the material in the non-fluidized state). Similarly, the refrigerant temperature must be higher than this temperature value to prevent the material from absorbing moisture.

[0032] When dry air with different dehumidification degrees is introduced into different cooling sections, while satisfying the condition that the material does not absorb moisture, it is also necessary to prevent the gas near the heat exchange wall from being cooled to a temperature close to the wall surface, where its relative humidity quickly rises to a saturated state and condenses on the wall surface, so as to avoid moisture absorption, agglomeration or scarring on the heat exchange wall or in the local material layer near the wall surface.

[0033] If a refrigerant of uniform temperature is used to enter each layer of cooling heat exchanger assembly in parallel, the temperature difference between the material and the refrigerant in the upper to middle cooling section is too large. Based on the above reasons, the probability of moisture absorption and scarring is relatively high; when the refrigerant is used to operate in series from bottom to top in countercurrent, since the heat transfer rate between the material layer and the wall surface is very low and the refrigerant flow rate is very large, the temperature rise of the refrigerant passing through the single-layer cooling heat exchanger assembly is still relatively low, and the temperature difference between the material and the refrigerant is also relatively large, so the probability of moisture absorption and scarring is still relatively high. In order to avoid this phenomenon, in the present invention, the fluidized cooling section and the gravity cooling section are divided into multiple cooling sections, i.e., multi-layer cooling heat exchanger assemblies. Each layer of cooling heat exchanger assembly forms a cooling section, and refrigerants of different temperatures are respectively introduced. The material temperature is higher at the entrance of the fluidized cooling section, and a higher temperature refrigerant is introduced into the cooling heat exchanger assembly. As the material temperature decreases, a lower refrigerant temperature is used, thereby limiting the temperature difference between the material and the refrigerant to a certain range, thereby avoiding the occurrence of this phenomenon.

[0034] b. Refrigerants of different temperatures are introduced into each layer of cooling heat exchanger components. When the material temperature is higher, ordinary refrigerants with lower costs, such as circulating water provided by the factory's public works, are used. When the material temperature is lower, cryogenic water refrigerants with higher costs are used, thereby saving production costs.

[0035] Preferably, each layer of the drying heat exchanger assembly and the cooling heat exchanger assembly adopts an independent heat exchange medium supply system, and the heat exchange medium supply system can independently control the flow rate and / or pressure and / or temperature of the heat exchange medium in the heat exchanger assembly connected thereto. Each layer of the heat exchanger assembly is provided with an independent heat exchange medium supply system, and the flow rate, pressure and temperature of the heat medium and the coolant can be adjusted independently, and the inlet temperature and / or flow rate of the heat medium and the coolant can be flexibly adjusted to ensure the drying efficiency of the drying heat exchanger assembly and ensure that the coolant temperature is higher than the temperature at which the material absorbs moisture and adheres, and to avoid scarring on the surface of the cooler, i.e., the cooling heat exchanger assembly.

[0036] Preferably, the gas distribution assembly of the present invention further comprises a replacement wind gas distribution assembly disposed in the gravity cooling section and connected to the gas supply system;

[0037] The replacement air gas distribution assembly is used to introduce dry gas into the shell body, so that the material layer is in an aerated state and the gas in the gaps between the particles is replaced, taking away the evaporated (volatile) moisture in the gas and the particles, reducing the relative humidity and dew point temperature of the gas environment in which the particles are located, so that a lower temperature refrigerant can be used to cool the material; the material in the aerated state can maintain good fluidity, so that the material is in a state of overall downward movement in the corresponding cooling section; the dry gas is preferably dry cold gas, which also has the effect of cooling the material and improves the cooling efficiency;

[0038] A layer of replacement wind gas distribution component is arranged below each layer of cooling heat exchanger components in the gravity cooling section.

[0039] Multiple layers of cooling heat exchanger components are arranged from top to bottom in the gravity cooling section, and a layer of displacement wind gas distribution component is arranged below each layer of cooling heat exchanger components. The technical significance is as follows:

[0040] a. In normal production, you can choose not to open, open one layer, open multiple layers, or all of the replacement wind gas distribution components according to the material characteristics and operation requirements. For example, for some materials, when the material temperature is high in the upper area of ​​the gravity cooling section, a small amount of moisture will still evaporate, while when the material temperature is low in the middle and lower areas of the gravity cooling section, moisture evaporation will stop. At this time, the upper gas distribution component should be opened without opening the lower gas distribution component; some materials need to be cooled to a very low temperature, and drier gas needs to be added to adapt to the lower temperature refrigerant. At this time, only the lower gas distribution component can be opened; some materials have poor fluidity, and they should maintain an appropriate inflation state throughout the cooling process to increase fluidity. At this time, all gas distribution components can be opened to introduce a small amount of dry gas; and for materials with good fluidity and no steam precipitation during the whole process, even no ventilation is required.

[0041] When the multi-layer gas distribution components are turned on, the replacement air volume of the cooling section at the top is the sum of the ventilation volumes of all the opened gas distribution components at the bottom, and the fluidizing air volume of the material fluidizing section is the sum of the ventilation volumes of all the gas distribution components below that position; and the actual operating wind speed of the material layer where the material is located (the fluidizing wind speed in the fluidizing section) is generated by all the air volumes in the cross-section of the material layer.

[0042] b. In practical applications, for materials with less obvious moisture absorption and scarring characteristics, the gas distribution components (including the second fluidized air gas distribution component and the replacement air gas distribution component) can be fed with gases of different dryness from top to bottom in sequence, as long as the dew point temperature is lower than the refrigerant inlet temperature of the cooling section where it is located to a certain extent, thereby further saving the energy consumption and equipment cost for gas dehumidification. The dryness of the dry gas should ensure that no condensation occurs on the wall of the cooling heat exchanger component where the refrigerant with the lowest temperature in the cooling section of the layer is located, and at the same time ensure that the material does not absorb moisture, agglomerate or scar when it is cooled by the wall of the cooling heat exchanger component where the refrigerant with the lowest temperature is located.

[0043] Preferably, when the replacement air distribution assembly is partially or fully operational, the operating wind speed generated by the ventilation volume or the sum of the ventilation volumes of the replacement air distribution assembly is 0 to 0.5 times the critical fluidization velocity calculated based on the average particle size of the material;

[0044] When the first fluidizing wind gas distribution assembly, the second fluidizing wind gas distribution assembly and the replacement wind gas distribution assembly are working at the same time, the operating wind speed generated when the ventilation volume of the second fluidizing wind gas distribution assembly is calculated separately is not less than 0.7 times the critical fluidization velocity calculated according to the average particle size of the material; the fluidization wind speed generated by the sum of the ventilation volumes of the second fluidizing wind gas distribution assembly and the replacement wind gas distribution assembly is not less than 1.2 times the critical fluidization velocity calculated according to the average particle size of the material; the fluidization wind speed generated by the sum of the ventilation volumes of the first fluidizing wind gas distribution assembly, the second fluidizing wind gas distribution assembly and all replacement wind gas distribution assemblies is not higher than 15 times the critical fluidization velocity calculated according to the average particle size of the material.

[0045] After the material passes through the upper fluidized cooling section, most of the humid gas has been displaced out of the material gap and is in a relatively dry gas environment. At this time, only a small amount of dry gas needs to be introduced through the displacement wind gas distribution component to bring out the small amount of moisture volatilized from the material; when selecting a variety of dry gases with different dryness levels, the lower displacement wind gas distribution component can choose to introduce drier gas than the dry gas introduced by the upper gas distribution component to further reduce the dew point of the gas environment in the material gap, and correspondingly, a lower temperature refrigerant can be used. The introduced dry gas not only brings out the wet steam, but also improves the fluidity of the material.

[0046] The maximum operating wind speed generated by the ventilation volume or the sum of the ventilation volumes in the gravity cooling section should use a lower value as much as possible when meeting the operating requirements. The fluidization number is best between 0 and 0.5. On the one hand, when the gas velocity is low, the resistance of the gas passing through the material layer is very low, and the power consumption of gas pressurization is small. On the other hand, when the operating gas velocity is close to the critical fluidizing gas velocity, the so-called "local fluidization" or "semi-fluidization" phenomenon will occur, causing defects such as gas short-circuiting, which in turn aggravates the gravity flow blockage in the unfluidized area, destroying the uniformity of the overall flow of the material layer flowing downward by gravity, thereby reducing the cooling effect.

[0047] The present invention preferably further comprises an auxiliary silo, the inlet of which is connected to the discharge port, and the outlet of which is connected to the feed port. The auxiliary silo is provided to quickly fill the shell body during the start-up process, so that the material reaches the material level above the heat exchanger assembly, shortening the start-up process. It can also be used as a temporary storage container during equipment failure inspection and repair to temporarily store the material after cooling.

[0048] Preferably, the auxiliary silo is located above the shell body, and can use gravity to feed materials into the shell body.

[0049] Preferably, the present invention further comprises a material level meter and a discharger with adjustable flow rate;

[0050] The material level meter is arranged on the top of the shell body and is used to measure the material level height of the material in the shell body;

[0051] The discharger is connected to the discharge port and is used to adjust the discharge speed of the material to control the material level height in the shell body. The discharger is used to control the uniform discharge of the material, and the flow rate can be adjusted. The discharge flow rate of the discharger is controlled by the material level electrical signal of the material level meter to control the material level height in the shell body, ensure a certain fluidized material layer to maintain stable fluidization, and at the same time make the material bury all the heat exchanger components to ensure the heat exchange efficiency, so as to achieve the effect of efficient drying and effectively remove moisture from the material.

[0052] Preferably, the gas supply system includes a gas dehumidification device, a gas heating device and a gas cooling device, and the heat exchange medium supply system includes a fluid pressure / flow control device or a fluid heating device and a fluid cooling device;

[0053] The gas dehumidification equipment is used to remove moisture from the gas to obtain dry gas, and the gas cooling equipment is used to control the temperature of the dry gas entering the fluidized cooling section and the gravity cooling section;

[0054] The gas heating device is used to heat the dry gas entering the fluidized drying section or the gas that has not been dehumidified by the gas dehumidification device; the fluid pressure / flow control device is used to control the pressure or flow of the heat medium or the coolant;

[0055] The fluid heating device is used to heat the liquid heat medium; in the fluidized drying section, the heat medium is not limited to fluids without phase change heat transfer such as hot water or heat transfer oil, but also includes fluids with phase change heat transfer, such as common water vapor; for steam, the pressure or flow entering the heat exchanger is controlled by a regulating valve, while for hot water or heat transfer oil, temperature and flow control are required;

[0056] The fluid cooling device is used to control the temperature of the refrigerant to prevent the material from absorbing moisture, agglomerating or forming scars on the wall of the heat exchanger.

[0057] Preferably, the drying heat exchanger assembly or the cooling heat exchanger assembly comprises a plurality of heat exchange tubes arranged at intervals in the horizontal direction, and the heat exchange tubes are serpentine tubes extending up and down;

[0058] Two adjacent serpentine heat exchange tubes are arranged in staggered rows. Compared with the horizontally extending serpentine tube arrangement, the vertically extending serpentine tube arrangement is conducive to forming a vertically penetrating material flow channel, reducing the resistance of the material flowing down, and forming a countercurrent or parallel heat exchange between the material and the refrigerant, rather than a cross-current heat exchange, which has a higher heat exchange efficiency and is less likely to cause temperature differences in different positions of the material in the same horizontal section. The two adjacent serpentine heat exchange tubes are arranged in staggered rows, which increases the number of diversions and confluences of the material in the internal flow channel of the heat exchanger assembly, increases the disturbance on the material side, and can increase the heat transfer coefficient on the material side; at the same time, increasing the flow of the material also helps to reduce the slight bonding of the material.

[0059] Preferably, the drying heat exchanger assembly is a tubular heat exchanger. The material above the first fluidizing air gas distribution assembly is in a good fluidized state, which can better overcome the phenomenon that material deposition is easy to occur on the upper part of the heat exchange tube. The heat exchange tube in the fluidized state has a greater disturbance to the material than the plate heat exchanger, thereby having a better heat transfer effect.

[0060] Preferably, the first fluidizing air gas distribution assembly, the second fluidizing air gas distribution assembly and the replacement air gas distribution assembly each comprise a plurality of gas distribution pipes arranged horizontally and spaced apart from each other, and air distribution holes are provided below the gas distribution pipes;

[0061] The air distribution holes are arranged in rows along the axial direction of the gas distribution pipe, and at least one row of air distribution holes is arranged under each gas distribution pipe;

[0062] The gas distribution pipe is a straight pipe, and the gas distribution pipe is perpendicular to the heat exchange pipe in the drying heat exchanger assembly or the cooling heat exchanger assembly, or the gas distribution pipe is perpendicular to the heat exchange plate in the drying heat exchanger assembly or the cooling heat exchanger assembly, that is, the horizontal extension direction of the gas distribution pipe is perpendicular to the horizontal extension direction of the heat exchange pipe in the drying heat exchanger assembly or the cooling heat exchanger assembly. By opening one or more rows of air distribution holes in the axial direction in the lower half of each gas distribution pipe, the gas in the pipe is sent to the material channel inside the box; the arrangement of the gas distribution pipe and the opening of the hole on the pipe wall can ensure that the gas is evenly diffused to the entire cross section of the shell and passes through the material layer upward; the cross-sectional shape of the gas distribution pipe can be circular, or elliptical, rhombus, flat rectangular or other shapes, and the shape of the air distribution hole is not only circular, but can be strip-shaped gaps or other shapes.

[0063] The arrangement of the gas distribution pipe extending in the horizontal direction perpendicular to the horizontal extension direction of the heat exchange tube or heat exchange plate is conducive to a more uniform distribution of gas in the heat exchange tube or heat exchange plate area, avoiding poor material fluidization or local blockage caused by insufficient local airflow.

[0064] The present invention also discloses a drying and cooling method, which utilizes the above-mentioned drying and cooling integrated machine, and comprises the following steps:

[0065] S1. Use the dried and cooled materials to completely bury the drying heat exchanger assembly and the cooling heat exchanger assembly in the shell body and reach a preset height above the drying heat exchanger assembly;

[0066] S2. Use the first fluidizing air gas distribution component to introduce hot dry gas or hot gas that has not been dehumidified into the shell body, and use the second fluidizing air gas distribution component to introduce dry gas or dry cold gas into the shell body, so that the material above the first fluidizing air gas distribution component and the second fluidizing air gas distribution component is in a fluidized state, ensuring that the material is evenly distributed in the cross section of the shell body, and enters the gravity cooling section in this evenly distributed state;

[0067] S3, using the drying heat exchanger assembly of the fluidized drying section to heat and dry the material, and at the same time using hot dry gas to heat and dry the material under fluidization, fully replacing the moist gas between the material particles, and taking the moisture precipitated in the material and in the moist gas out of the shell body;

[0068] Alternatively, the material is heated and dried using hot gas without dehumidification under fluidization, and the moisture precipitated from the material is taken out of the shell body;

[0069] S4. At the same time, the material is cooled by using the cooling heat exchanger components of the fluidized cooling section and the gravity cooling section;

[0070] At the same time, the second fluidizing air gas distribution component is used to introduce dry gas into the fluidizing cooling section to fluidize the material, fully replace the wet gas between the material particles with dry gas, and bring the moisture in the wet gas and the moisture precipitated in the material out of the shell body;

[0071] The refrigerant inlet temperature of each cooling heat exchanger component is controlled to be higher than the temperature at which the material on the material side of the corresponding cooling heat exchanger component absorbs moisture, agglomerates, or forms scars on the heat exchanger wall.

[0072] Preferably, in step S1, the method of using materials to completely bury the drying heat exchanger assembly and the cooling heat exchanger assembly in the shell body is:

[0073] S11. A first fluidizing air gas distribution assembly and a second fluidizing air gas distribution assembly are arranged at the upper end of the shell body. Before drying and cooling the material, the dried and cooled material is quickly added to the shell body to a preset height through an auxiliary silo, manual feeding or other drying and cooling system continuous transfer;

[0074] S12, while feeding the material, when the material level rises to the second fluidizing air gas distribution component of the fluidized cooling section, start the second fluidizing air gas distribution component and introduce gas to make the material above the gas distribution component enter a fluidized state;

[0075] S13, when the material level reaches the first fluidizing air gas distribution component, the corresponding first fluidizing air gas distribution component is opened at the same time, and gas is introduced until the material layer reaches the material level height of normal production. During the whole process, the materials above the second fluidizing air gas distribution component are in a fluidized state;

[0076] The above operations are carried out in sequence upwards until the material level reaches a preset height, and finally a fluidized drying section, a fluidized cooling section and a gravity cooling section are arranged vertically;

[0077] According to the needs, the gas introduced into the second fluidizing air gas distribution component can be dry gas or dry cold gas; the gas introduced into the first fluidizing air gas distribution component can be hot dry gas or hot gas without dehumidification;

[0078] S14. Next, the material to be dried and cooled is continuously fed into the shell body from the feed port at the top of the shell body.

[0079] Preferably, the present invention further comprises step S5:

[0080] On the basis of respectively setting the first fluidizing air gas distribution assembly and the second fluidizing air gas distribution assembly in the fluidized drying section and the fluidized cooling section, a plurality of layers of replacement air gas distribution assemblies are sequentially set from top to bottom inside the gravity cooling section;

[0081] At the same time, a small amount of dry gas or dry cold gas is introduced into the gravity cooling section by using the replacement wind gas distribution component to bring a small amount of moisture in the gas between the material particles out of the shell body, so that the material remains in a dry cold gas environment.

[0082] Working principle and beneficial effects of the present invention:

[0083] Gas or dry gas is blown into the shell of the shell body through the first and second fluidizing air gas distribution components to make the materials above the fluidizing air gas distribution pipe present a fluidized state, and the characteristics of the gas-solid fluidization phenomenon are used to process the raw materials as follows:

[0084] a. Utilize the high turbulence and high back-mixing characteristics of fluidization to eliminate the feed cone and the segregation phenomenon in the feeding process, so that the material is evenly distributed in the cross section of the shell body.

[0085] In theory, it is always hoped that the material moves downward in the box of the gravity cooling section in an overall flow manner, so that the material on the entire cross section undergoes the same cooling process, thereby obtaining a uniform and consistent cooling depth. However, actual powdery or granular materials always have a certain particle size distribution range. When the material falls freely from the feed port to the stationary heat exchanger component or the upper part of the material at a certain speed, a conical material accumulation area will be formed, namely: the feed cone; after the feed cone is formed, the subsequent particles will appear in the process of falling. Large particle size materials are enriched at the periphery of the cone, and small particle size and powdery materials are enriched in the center, namely: particle segregation. The weight of the feed cone and the impact force of the feed exert uneven pressure on the material below it, causing the material in the central area of ​​the feed cone to move down quickly while the material around it moves down slowly, affecting the uniformity of the overall flow of the material, thereby causing differences in the cooling depth of materials in different box cross-sectional areas. Since the materials moving downward in the gravity cooling section in an overall flow manner have the same cooling time, when segregation occurs, uneven material particle size distribution will appear on the cross-section of the shell body, and the cooling rate of coarse particles is slower than that of fine particles. This uneven cooling rate will cause the material temperature around the material cone to be higher than that of the material in the center area, thereby exacerbating the cooling temperature difference.

[0086] The present invention sets a material fluidization section (i.e., a fluidized drying section and a fluidized cooling section) above the shell body. In the fluidized state, the material layer is in a high turbulence and high backmixing state, the material has fluid-like characteristics, the feed cone is automatically eliminated, and a horizontal upper surface of the fluidized bed is formed, so that a uniform material pressure is generated on the entire cross-section of the shell body, which is conducive to the overall flow of the material from top to bottom in the gravity cooling section box, and increases the uniformity of the cooling time of the material at various locations in the cross-section of the shell body; further, in the fluidized state, the particle size distribution of the material in the horizontal direction is uniform, and there is no material segregation phenomenon, thereby ensuring that the material enters the subsequent cooling process with a uniform particle size distribution, eliminating the uneven cooling caused by different feed particle size distributions.

[0087] b. Use the high heat / mass transfer rate of fluidized drying to intensify the drying process and improve the drying capacity per unit cross-sectional area.

[0088] When the material is in fluidization, the heat transfer process between the material and the heat exchanger, and the heat transfer / mass transfer process between the gas and the material are significantly enhanced, thereby obtaining a higher drying efficiency or a lower final moisture requirement; the fluidized drying section has a heat transfer capacity per unit area far exceeding that of the gravity cooling section, that is, compared with the slowly moving material layer in an aerated state, it has a significant increase in heat and mass transfer rate, which is very beneficial for superimposing a drying section on a gravity cooler (in this patent, it is a gravity cooling section), because the heat required to remove moisture by thermal drying is much greater than the heat required to cool the material, and the fermentation product has a high requirement for the cooling depth, often requiring cooling to room temperature or even lower temperature, so the gravity cooling section is often a vertically arranged container, which requires to maximize the drying capacity on a limited cross-section, thereby increasing the feed moisture, expanding the scope of application of the material, or reducing the requirements for the final moisture content of the raw material pre-drying; when hot dry gas is used, the moisture content in the gas can be further reduced, the mass transfer driving force can be increased, and the dry gas can also carry more moisture, thereby reducing the moisture content of the material at the end of drying. Fermentation products often have the characteristics of agglomeration and scarring during the drying process. The violent turbulence and backmixing between materials in fluidization have a good dispersion and breaking effect on the wet materials. The strong scouring of the shell and the wall of the heat exchanger also reduces or avoids the tendency of the material to scar on the wall.

[0089] c. Utilizing the high gas-solid contact efficiency of fluidization, the hot and humid gas in the gaps between the material particles in the fluidized cooling section is efficiently replaced by dry gas, while the material is pre-cooled and its moisture is homogenized.

[0090] Powdered or granular materials have a certain porosity. After drying, the gaps between the particles of the materials are usually filled with hot and humid gas. The moisture can be various components such as water vapor and methanol vapor. The relative humidity of moisture in the gas is very low at high temperature, but after cooling, the relative humidity becomes higher, and it is easier to be absorbed by the particles, thereby increasing the moisture in the particles, that is, the material absorbs moisture. When the temperature of the humid gas drops below the dew point temperature of the moisture, it will condense on the surface of the particles and the wall of the heat exchanger. In particular, the temperature of the heat exchanger wall and its vicinity is very low, and the humid gas is more likely to condense, directly causing the material to agglomerate or the heat exchanger wall to scar. Therefore, the humid hot gas must be replaced for the moisture-absorbing material so that it is in a dry gas environment. The fluidizing gas can play such a role.

[0091] Furthermore, in the fluidized state, the contact efficiency between the particles and the fluidizing gas is very high, and the gas around each particle can be fully replaced; the high mass transfer rate in the fluidized state can also replace the gas in the capillary pores on the surface of the particles to a certain extent; its heat transfer efficiency is also very high, so as to make full use of the thermal energy of the low-temperature fluidizing gas to reduce the temperature of the feed, eliminate the feed temperature and moisture differences between particles with different moisture contents and different particle sizes, and achieve better cooling and moisture homogenization effects.

[0092] d. The cooling section (including the fluidized cooling section) is divided into multi-layer cooling sections by arranging multi-layer cooling heat exchangers and multi-layer gas distribution components. By controlling the temperature difference between the material and the refrigerant in each cooling section and introducing dry air with different flow rates and dryness levels, the material flow is promoted, moisture absorption / caking / scarring of the material during deep cooling is avoided, and the cooling efficiency and cooling uniformity of the cooling section are improved, thereby reducing or avoiding the hidden danger of agglomeration in the product transportation or storage process. In addition, when the gas flow introduced by the fluidizing air gas distribution component of the present invention makes the corresponding material layer in a fluidized bed, the effect of eliminating the feed cone and material segregation is basically independent of the cross-sectional size and shape of the bed. Therefore, a larger cross-sectional area can be used to place a larger heat exchanger component or a multi-layer heat exchanger component with different combinations, without worrying about the impact of non-integrated flow and uneven particle size distribution on cooling uniformity caused by the increase in the height of the feed cone. Therefore, a smaller aspect ratio (for a rectangular shell, it can be described as a height-to-width ratio or a height-to-length ratio, or a height-to-cross-sectional area ratio) can be used to obtain a greater material processing capacity, or when the feed amount is the same or the material cooling temperature difference is the same, a lower equipment height can be used, which correspondingly reduces the plant height or the secondary lifting height of the material, thereby increasing investment or energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0093] Figure 1 This is a schematic structural diagram of the drying and cooling integrated machine according to Embodiment 1 of the present invention;

[0094] Figure 2This is a schematic structural diagram of the drying and cooling integrated machine according to Embodiment 2 of the present invention;

[0095] Figure 3 This is a schematic diagram of the partial structure of the drying and cooling integrated machine described in Example 3 of the present invention;

[0096] Figure 4 It is a schematic diagram of the positional relationship between the gas distribution component and the heat exchanger component;

[0097] Figure 5 It is a schematic diagram of the structure of the gas distribution component in the longitudinal section direction;

[0098] Figure 6 It is a schematic diagram of the structure of the cross-section direction of the gas distribution component;

[0099] Figure 7 It is a schematic diagram of the structure of the gas exchange holes on the heat exchange plate;

[0100] Figure 8 It is a structural schematic diagram of staggered arrangement of upper and lower adjacent tubular heat exchangers;

[0101] Fig. 9 It is a structural schematic diagram of the staggered arrangement of upper and lower adjacent plate heat exchangers;

[0102] In the figure, 1 is a shell body, 2 is a drying heat exchanger assembly, 3 is a cooling heat exchanger assembly, 31 is a heat exchanger, 32 is a heat exchange tube, 33 is a heat exchange plate, 4 is a first fluidizing air gas distribution assembly, 5 is a second fluidizing air gas distribution assembly, and 6 is a replacement air gas distribution assembly;

[0103] 1000 first material channels, 2000 air distribution channels, 3000 second material channels, 4000 air distribution holes;

[0104] 101 feed port, 102 exhaust port, 103 discharge port, 104 upper surface of material layer, 105 feed material flow, 106 discharge material flow, 107 expansion section;

[0105] 100 fluidized drying section, 200 fluidized cooling section, 300 gravity cooling section;

[0106] 7 auxiliary silo, 8 material level meter, 9 discharger, 10 gas distribution pipe;

[0107] 400 inlet distribution main pipe, 500 outlet distribution main pipe, 600 first connecting pipe;

[0108] 700 gas distribution main pipe, 800 second connecting pipe. DETAILED DESCRIPTION

[0109] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings.

[0110] In the present invention, the definition of net cross section is: the cross-sectional area of ​​the material channel after deducting the cross-sectional area occupied by the heat exchanger assembly on any horizontal cross-sectional area of ​​the box where the fluidized drying section, fluidized cooling section and gravity cooling section are located.

[0111] Definition of fluidization number: the ratio of operating wind speed to critical fluidization velocity calculated based on average particle size of the material; the operating wind speed is the average wind speed calculated based on the net cross-section of the box. In the material fluidization section, the fluidization wind speed is generally used to refer to the operating wind speed.

[0112] Calculation method of critical fluidization velocity: Calculate according to the calculation formula given on page 166 of "Fluidized Drying Technology and Equipment" published by Science Press in 1996, written by Tong Jingshan.

[0113] Example 1

[0114] like Figure 1 As shown, a drying and cooling integrated machine includes a shell body 1, a drying heat exchanger assembly 2, a cooling heat exchanger assembly 3, a gas distribution assembly, an air supply system and a heat exchange medium supply system (the air supply system and the heat exchange medium supply system are not shown in the figure).

[0115] The drying heat exchanger assembly 2 and the cooling heat exchanger assembly 3 are plate heat exchangers or tube heat exchangers. The heat exchange tubes in the tube heat exchanger are arranged at intervals from each other, and the heat exchange plates in the plate heat exchanger are arranged at intervals from each other. Figure 5 and Figure 6 As shown, a first material channel 1000 running through from top to bottom is provided between the heat exchange plates 33 or between the heat exchange tubes 32 of the drying heat exchanger assembly 2 and the cooling heat exchanger assembly 3, that is, the gap between the heat exchange tubes in the tubular heat exchanger and the gap between the heat exchange plates in the plate heat exchanger are the first material channel 1000.

[0116] like Figure 4 , Figure 5 and Figure 6 As shown, the gas distribution assembly includes an air distribution channel 2000 distributed along the cross section of the shell body 1, and the outer side of the air distribution channel 2000 is provided with a second material channel 3000 distributed along the cross section of the shell body 1 at intervals, and the side wall of the air distribution channel 2000 is provided with air distribution holes 4000 communicating with the inner cavity of the shell body 1. The gas distribution assembly is a tubular structure, specifically, including gas distribution pipes 10 arranged at intervals along the cross section of the shell body 1, the air distribution channel 2000 is the internal channel of the gas distribution pipe 10, and the gas distribution pipe 10 is provided with air distribution holes 4000, and the air distribution holes 4000 are opened downward; the gas distribution pipes 10 are straight pipes parallel to each other.

[0117] like Figure 1As shown, the shell body 1 is a vertical shell, usually having a rectangular cross section, a feed port 101 and an exhaust port 102 are arranged at the top of the shell body 1, and a discharge port 103 is arranged at the bottom of the shell body 1.

[0118] Specifically, the shell body 1 is provided with a fluidized drying section 100, a fluidized cooling section 200, a gravity cooling section 300 and a discharging section from top to bottom, and the upper half of the fluidized drying section is also a feeding section; the feeding section is generally a shell having a rectangular cross-section that is consistent from top to bottom, and one or more feeding ports 101 are provided on the top of the feeding section shell for adding powdery and granular materials to be processed, such as Figure 1 As shown, a feed material flow 105 is formed; one or more exhaust ports 102 are provided at the top of the feed section shell for exhausting gas; the internal space of the feed section shell is used to accommodate materials, and the materials usually fill a part of the shell in the working state, and have an obvious material layer upper surface 104 under the fluidization effect, and there is a certain height of space above the material, and the small particles entrained in the tail gas are re-settled to the material layer under the action of gravity at this height; the bottom of the feed section shell is open, usually equal to the cross section of the feed section shell, and is used to connect with the feed end of the fluidized drying section 100, or the feed section itself is the upper half of the fluidized drying section 100, that is, there is a certain amount of residual space above the upper surface of the material layer of the fluidized drying section 100. A material level meter is installed on the feed section shell to measure the material level height and transmit it to the control system.

[0119] In this embodiment, Figure 1 As shown, the shell body 1 is provided with a fluidized drying section 100, a fluidized cooling section 200 and a gravity cooling section 300 from top to bottom.

[0120] The fluidized drying section 100 is provided with a drying heat exchanger assembly 2 connected to a heat exchange medium supply system.

[0121] The fluidized cooling section 200 and the gravity cooling section 300 are provided with a cooling heat exchanger assembly 3 connected to a heat exchange medium supply system.

[0122] The heat exchange medium supply system is used to provide hot medium and cold medium to the drying heat exchanger assembly 2 and the cooling heat exchanger assembly 3 respectively.

[0123] In this embodiment, the drying heat exchanger assembly 2 is preferably a tubular heat exchanger, because the heat exchange tube has better pressure and temperature resistance than the heat exchange plate, can better adapt to high temperature and high pressure heat sources such as superheated steam, and the material above the first fluidized air gas distribution assembly is in a good fluidized state, which can better overcome the phenomenon that material deposition is easy to occur on the upper part of the heat exchange tube. The heat exchange tube in the fluidized state has a greater disturbance to the material than the plate heat exchanger, so it has a better heat transfer effect. In the gravity cooling section 300, a heat exchanger in the form of a heat exchange plate, i.e., a plate heat exchanger, is preferably used. When the material is in an overall flow state of an inflated state that moves slowly downward, the flow channel between the heat exchange plates is more conducive to the flow of materials and gas, avoiding local flow blockage. In the fluidized cooling section, both forms of heat exchangers can be used. When a tubular heat exchanger is used, it should be combined with a higher fluidization speed to reduce the possibility of local flow blockage. The tubular heat exchanger includes a plurality of heat exchange tubes arranged at intervals, and the heat exchange tube is a serpentine tube extending up and down, and two adjacent serpentine heat exchange tubes are arranged in an up-and-down staggered manner.

[0124] The external space of the drying heat exchanger assembly 2 and the cooling heat exchanger assembly 3 is a material channel, and the internal space is a heat exchange medium channel. The two are separated by the wall of the drying heat exchanger assembly 2, and heat is transferred through the wall.

[0125] like Figure 7 As shown, when the drying heat exchanger assembly 2 and the cooling heat exchanger assembly 3 are plate heat exchangers, in order to improve the circulation of the gas inside the drying heat exchanger assembly 2 and the cooling heat exchanger assembly 3, gas exchange holes can be provided on the heat exchange plates 33 of the plate heat exchangers. The diameter of the gas exchange holes can generally be 10-20 mm, and the gas can pass through them to increase the gas flow between different heat exchange plates to stabilize the gas flow state.

[0126] The plate heat exchanger is provided with rows of spot welding areas and staggered line-shaped welds. A pillow-shaped expansion area is formed between the spot welding areas as a channel for the heat exchange medium. The surrounding area of ​​each local welding area is raised to form a generally bowl-shaped pit. The staggered line-shaped welds form a serpentine path for the heat exchange medium to pass through. The pits in adjacent rows (or columns) are usually staggered to increase the disturbance during the flow of internal fluid and the flow of external powder and granular materials, and the overall flow mode of the serpentine path avoids internal fluid short-circuiting, increases the process length, and increases the flow speed; the above measures can significantly improve the flow and heat transfer characteristics of fluids and materials.

[0127] like Figure 1As shown, the shell body 1 is provided with an inlet distribution main pipe 400 and an outlet distribution main pipe 500 of the heat exchange medium on the outside of the shell, and a first connecting pipe 600 for connecting the drying heat exchanger assembly 2 or the cooling heat exchanger assembly 3 with the heat exchange medium distribution main pipe. The heat exchange medium enters each heat exchanger assembly (including the drying heat exchanger assembly 2 and the cooling heat exchanger assembly 3) from the inlet distribution main pipe, and is indirectly heat-exchanged with the material in the heat exchanger assembly before being collected in the outlet distribution main pipe. The heat exchange medium can enter the heat exchanger assembly from the lower distribution main pipe and then be discharged from the upper distribution main pipe, that is, the inlet distribution main pipe 400 is arranged below the outlet distribution main pipe 500, thereby forming a countercurrent heat exchange in the opposite direction of the material flow direction, obtaining a higher heat exchange temperature difference, and heating or cooling the material faster. The heat exchange medium can also enter the heat exchanger assembly from the upper part and be discharged from the lower part, because the heat exchange temperature difference is low, so that the material heating process or cooling process can be carried out gently.

[0128] When the drying heat exchanger assembly 2 adopts steam heat source, the inlet distribution main pipe of the heat source is located at the upper part of the drying heat exchanger assembly 2, and the outlet distribution main pipe is located at the lower part of the drying heat exchanger assembly 2; when hot water or heat transfer oil heat source is adopted, the setting is reversed, and a countercurrent heat exchange process is formed between the heat source and the material.

[0129] like Figure 1 As shown, the gas distribution assembly includes a first fluidizing air gas distribution assembly 4 and a second fluidizing air gas distribution assembly 5 respectively arranged in the fluidizing drying section 100 and the fluidizing cooling section 200, and the first fluidizing air gas distribution assembly 4 and the second fluidizing air gas distribution assembly 5 are respectively connected to the gas supply system. Figure 1 As shown, a first fluidizing air gas distribution assembly 4 is provided below the drying heat exchanger assembly 2. The fluidizing cooling section 200 is provided with a layer of cooling heat exchanger assembly 3, and a second fluidizing air gas distribution assembly 5 is provided below the cooling heat exchanger assembly 3.

[0130] like Figure 4 As shown, the first fluidizing air gas distribution assembly 4 and the second fluidizing air gas distribution assembly 5 include a plurality of gas distribution pipes 10 installed inside the shell body 1. In this embodiment, the gas distribution pipes 10 are straight pipes. The plurality of gas distribution pipes 10 are distributed on the same horizontal plane and are evenly arranged in parallel with each other. The horizontal extension direction of the gas distribution pipes 10 is perpendicular to the horizontal extension direction of the heat exchange pipes in the drying heat exchanger assembly 2 and the cooling heat exchanger assembly 3 (such as Figure 4 (a)), or the horizontal extension direction of the gas distribution pipe 10 is perpendicular to the horizontal extension direction of the heat exchange plates in the drying heat exchanger assembly 2 and the cooling heat exchanger assembly 3 (as shown in FIG. Figure 4(b) shows), the lower half of each gas distribution pipe 10 is provided with one or more rows of holes along the length direction, which are used to deliver the gas in the pipe to the material channel inside the shell body 1. The arrangement of the gas distribution pipes 10 and the opening of the holes on the pipe wall are used to ensure that the gas is evenly diffused over the entire shell cross-section of the shell body 1 and passes upward through the material layer; a gas distribution main pipe 700 is installed outside the shell body 1, as well as a second connecting pipe 800 connecting the gas distribution pipe to the main pipe.

[0131] The cross-sectional shape of the gas distribution pipe 10 can be circular, elliptical, diamond-shaped or other shapes. The shape of the opening is not limited to circular, but can be strip-shaped gaps or other shapes. The number of rows and arrangement of the openings are not specific.

[0132] The first fluidizing air gas distribution component 4 is used to introduce hot dry gas or hot gas that has not been dehumidified by the initial equipment into the shell body 1. Its ventilation volume merges with the ventilation volume of the second fluidizing air gas distribution component 5, so that the material in the fluidized drying section 100 is fluidized. The high turbulence and high back-mixing characteristics of the material in fluidization are used to eliminate the feed cone and feed segregation phenomenon, so that the material entering the fluidized drying section 100 is spread in the horizontal direction and enters the fluidized cooling section 200 with uniform particle size distribution; the high heat transfer / mass transfer rate under fluidization can be used to obtain higher drying efficiency or lower final moisture requirements; the hot gas also provides part of the heat required for drying and carries out the evaporated moisture; when hot dry gas is used, the mass transfer driving force can be further increased to carry more moisture, thereby reducing the moisture content of the material at the end of drying; the high turbulence and high back-mixing characteristics of the material in fluidization have a good dispersion and block breaking effect on the wet material, and the strong scouring of the shell and the wall of the heat exchanger also reduces or avoids the tendency of the material to form scars on the wall.

[0133] The second fluidizing air gas distribution assembly 5 is used to introduce dry gas into the shell body 1, so that the material in the fluidized cooling section 200 is in a fluidized state, and the high gas-solid contact efficiency of fluidization is utilized to achieve efficient replacement of the hot and humid gas in the gaps between the material particles in the fluidized cooling section through the dry gas, and at the same time, the material is pre-cooled and the moisture is homogenized, and it is ensured that the particle size of the material in the fluidized cooling section 200 is evenly distributed and the moisture in the gaps between the materials is fully replaced and discharged before entering the gravity cooling section 300. Preferably, dry cold gas is introduced through the second fluidizing air gas distribution assembly 5, and the heat energy of the low-temperature gas is utilized to further cool the material.

[0134] In order to achieve the above objectives, in this embodiment, the gas supply system includes a gas dehumidification device, a gas heating device and a gas cooling device, and the heat exchange medium supply system includes a fluid pressure / flow control device or a fluid heating device, a fluid cooling device.

[0135] The gas dehumidification equipment is used to remove moisture from the gas to obtain dry gas, and the gas cooling equipment is used to control the temperature of the dry gas entering the fluidized cooling section 200 and the gravity cooling section 300 .

[0136] The gas heating device is used to heat the dry gas entering the fluidized drying section 100 or the gas that has not been dehumidified by the gas dehumidification device.

[0137] The fluid pressure / flow control device is used to control the pressure or flow of the heating medium or the cooling medium.

[0138] The fluid heating device is used to heat liquid heat medium.

[0139] The fluid cooling device is used to control the temperature of the refrigerant to prevent the material from absorbing moisture, agglomerating or forming scars on the wall of the heat exchanger.

[0140] In this embodiment, the upper and lower cross-sectional areas of the shells of the fluidized drying section 100 and the fluidized cooling section 200 are uniform, and the fluidizing wind speed of the first fluidizing wind gas distribution component 4 and the second fluidizing wind gas distribution component 5 is the average wind speed calculated using the horizontal net cross-sectional areas of the fluidized drying section 100 and the fluidized cooling section 200. When the first fluidizing wind gas distribution component 4 and the second fluidizing wind gas distribution component 5 work simultaneously, the fluidizing wind speed generated by the ventilation volume of the second fluidizing wind gas distribution component 5 is not less than 1 times of the critical fluidizing speed calculated according to the average particle size of the material; the fluidizing wind speed generated by the sum of the ventilation volumes of the first fluidizing wind gas distribution component 4 and the second fluidizing wind gas distribution component 5 is not less than 1.5 times of the critical fluidizing speed calculated according to the average particle size of the material; the fluidizing wind speed generated by the sum of the ventilation volumes of the first fluidizing wind gas distribution component 4 and the second fluidizing wind gas distribution component 5 is not higher than 15 times of the critical fluidizing speed calculated according to the average particle size of the material.

[0141] The fluidized cooling section 200 and the gravity cooling section 300 are provided with more than two layers of cooling heat exchanger components 3 from top to bottom, each layer of cooling heat exchanger components 3 forms a cooling section, and the temperature of the refrigerant of each layer of cooling heat exchanger components 3 decreases from top to bottom. Figure 1 As shown, three layers of cooling sections are provided in this embodiment.

[0142] Each layer of drying heat exchanger assembly 2 and cooling heat exchanger assembly 3 adopts an independent heat exchange medium supply system, and the heat exchange medium supply system can independently control the flow rate and / or pressure and / or temperature of the heat exchange medium in the heat exchanger assembly connected thereto.

[0143] like Figure 1As shown, the gas distribution assembly also includes a replacement wind gas distribution assembly 6 arranged in the gravity cooling section 300 and connected to the gas supply system, and the structure and arrangement of its gas distribution pipe 10 are the same as those of the first fluidizing wind gas distribution assembly 4 and the second fluidizing wind gas distribution assembly 5.

[0144] The replacement wind gas distribution assembly 6 is used to introduce dry gas into the shell body 1.

[0145] like Figure 1 As shown, a layer of replacement wind gas distribution assembly 6 is arranged below each layer of cooling heat exchanger assembly 3 in the gravity cooling section 300 .

[0146] In this embodiment, the upper and lower cross-sectional areas of the gravity cooling section 300 are uniform. When the replacement wind gas distribution component 6 is partially or fully working, the operating wind speed of the replacement wind gas distribution component 6 is the average wind speed calculated according to the horizontal net cross-sectional area of ​​the gravity cooling section 300. The operating wind speed generated by the ventilation volume or the sum of the ventilation volumes of the replacement wind gas distribution component 6 is 0~0.5 times the critical fluidization velocity calculated according to the average particle size of the material.

[0147] When the first fluidizing wind gas distribution component 4, the second fluidizing wind gas distribution component 5 and the replacement wind gas distribution component 6 are working at the same time, the operating wind speed generated when the ventilation volume of the second fluidizing wind gas distribution component 5 is calculated separately is not less than 0.7 times the critical fluidization speed calculated according to the average particle size of the material; the fluidization wind speed generated by the sum of the ventilation volumes of the second fluidizing wind gas distribution component 5 and the replacement wind gas distribution component 6 is not less than 1.2 times the critical fluidization speed calculated according to the average particle size of the material; the fluidization wind speed generated by the sum of the ventilation volumes of the first fluidizing wind gas distribution component 4, the second fluidizing wind gas distribution component 5 and all the replacement wind gas distribution components 6 is not higher than 15 times the critical fluidization speed calculated according to the average particle size of the material. Figure 1 As shown, the drying and cooling integrated machine further includes an auxiliary silo 7 , the inlet of the auxiliary silo 7 is connected to the discharge port 103 , and the outlet of the auxiliary silo 7 is connected to the feed port 101 .

[0148] like Figure 1 As shown, the drying and cooling integrated machine further includes a material level meter 8 and a discharger 9 with adjustable flow rate.

[0149] The material level meter 8 is arranged on the top of the shell body 1 and is used to measure the material level height of the material in the shell body 1 .

[0150] The discharger 9 is connected to the discharge port 103, and is used to adjust the discharge speed of the material, control the size of the discharge flow 106, and control the material level height of the material in the shell body 1. In this embodiment, a pneumatic conveying device is used for feeding, that is, the outlet of the discharger 9 is connected to the pneumatic conveying device, and the air inlet of the pneumatic conveying device adopts the same parameters as the displacement air inlet of the gravity cooling section. The pneumatic conveying device is provided with a return bypass for feeding the auxiliary silo 7.

[0151] The discharging device 9 can be any one of various forms such as a rotary air lock discharge valve, a vibrating discharging device, a belt discharging device, a single-axis or multi-axis spiral discharging device, etc. The discharging device 9 has a driving device and a discharging speed controller. The discharging speed controller receives the electrical signal of the level meter 8 installed on the top of the shell body 1, and then controls the discharging device 9 to adjust the discharging flow rate to ensure that the upper surface of the material layer is higher than the upper surface of the first fluidizing wind gas distribution component 4 of the fluidized drying section 100 by a certain height, thereby forming a fluidized material layer of a certain height on its upper part, ensuring the uniform effect on the material, and realizing the drying or deep drying of the material to be dried.

[0152] The discharge section is a discharge cone hopper that is larger at the top and smaller at the bottom, and is used to receive powdery or granular materials coming down from the gravity cooling section 300; the upper part of the cone hopper has the same cross-section as the gravity cooling section 300 and is connected to it, and the cone hopper gradually shrinks from top to bottom to transition to the same cross-section as the discharge port 103 and is connected to it.

[0153] One or more auxiliary discharging devices such as vibration and knocking can be installed on the wall of the discharging section to assist the flow of materials in the cone bucket through mechanical vibration or knocking; or one or more auxiliary discharging devices for compressed gas impact can be installed to loosen the materials by instantaneous release of compressed air. The function of the auxiliary discharging device is to prevent the material from being locally compacted or "bridged" and other flow obstructions, and ensure that the material is discharged smoothly in an overall flow manner.

[0154] The drying and cooling integrated machine also includes support, lifting lugs, flanges, inspection doors, manholes, hand holes, sight glasses, instrument mounting seats (holes) and other auxiliary components and structures for supporting, fixing, hoisting, connecting, inspecting, observing, and testing. These are required for conventional engineering or equipment design and will not be described in detail here.

[0155] The material discharging speed is controlled by the discharging device 9 to ensure that the upper surface of the material layer is higher than the uppermost drying heat exchanger component 2 by a certain height, thereby ensuring that the heat exchanger component is completely buried in the material.

[0156] The upper surface 104 of the fluidized material layer only needs to be located above the drying heat exchanger assembly 2 (eg 0-200 mm), which ensures that the heat exchanger is fully filled with material to exchange heat with the material and reduces the energy consumption required to overcome the resistance of the material layer.

[0157] A drying and cooling method, using the above-mentioned drying and cooling integrated machine, comprises the following steps:

[0158] S1. Use the dried and cooled materials to completely bury the drying heat exchanger assembly 2 and the cooling heat exchanger assembly 3 in the shell body 1 and reach a preset height above the drying heat exchanger assembly 2.

[0159] S2. Use the first fluidizing air gas distribution component 4 to introduce hot dry gas or non-dehumidified hot gas into the shell body 1, and use the second fluidizing air gas distribution component 5 to introduce dry gas or dry cold gas into the shell body 1, so that the material above the first fluidizing air gas distribution component 4 and the second fluidizing air gas distribution component 5 is in a fluidized state, ensuring that the material is evenly distributed in the cross section of the shell body 1, and enters the gravity cooling section 300 in this evenly distributed state.

[0160] S3. The material is heated and dried using the drying heat exchanger assembly 2 of the fluidized drying section 100. At the same time, the material is heated and dried using hot dry gas under fluidization to fully replace the moist gas between the material particles, and the moisture precipitated from the material and in the moist gas is brought out of the shell body 1.

[0161] Alternatively, the material is heated and dried by using hot gas without dehumidification under fluidization, so that the moisture precipitated from the material is brought out of the shell body 1.

[0162] S4. At the same time, the cooling heat exchanger assembly 3 of the fluidized cooling section 200 and the gravity cooling section 300 is used to cool the material.

[0163] At the same time, dry gas is introduced into the fluidized cooling section 200 by using the second fluidizing air gas distribution component 5 to fluidize the material, fully replace the moist gas between the material particles with dry gas, and bring the moisture in the moist gas and the moisture precipitated in the material out of the shell body 1.

[0164] The refrigerant inlet temperature of each cooling heat exchanger assembly 3 is controlled to be higher than the temperature at which the material on the material side of the corresponding cooling heat exchanger assembly 3 absorbs moisture, agglomerates, or forms scars on the heat exchanger wall.

[0165] In step S1, the method of using materials to completely bury the drying heat exchanger assembly 2 and the cooling heat exchanger assembly 3 in the shell body 1 is:

[0166] S11. A first fluidizing air gas distribution assembly 4 and a second fluidizing air gas distribution assembly 5 are arranged at the upper end of the shell body 1. Before the material is dried and cooled, the dried and cooled material is quickly added to the shell body 1 to a preset height through an auxiliary silo 7, manual feeding or continuous transfer by other drying and cooling systems.

[0167] S12. While the material is being added, when the material level reaches the second fluidizing air gas distribution component 5 of the fluidizing cooling section 200, the second fluidizing air gas distribution component 5 is started and gas is introduced to fluidize the material above the gas distribution component.

[0168] S13. When the material level reaches the first fluidizing air gas distribution component 4, the corresponding first fluidizing air gas distribution component 4 is opened at the same time, and gas is introduced until the material layer reaches the material level of normal production. During the whole process, the materials above the second fluidizing air gas distribution component 5 are in a fluidized state.

[0169] The above operations are performed upwards in sequence until the material level reaches a preset height, and finally a fluidized drying section 100, a fluidized cooling section 200 and a gravity cooling section 300 arranged vertically are formed.

[0170] As required, the gas introduced into the second fluidizing air gas distribution component 5 can be dry gas or dry cold gas; the gas introduced into the first fluidizing air gas distribution component 4 can be dry gas or hot gas without dehumidification.

[0171] S14, then, the material to be dried and cooled is continuously fed into the shell body 1 from the feed port 101 at the top of the shell body 1.

[0172] The drying and cooling method further comprises step S5:

[0173] On the basis of respectively setting the first fluidizing air gas distribution assembly 4 and the second fluidizing air gas distribution assembly 5 in the fluidizing drying section 100 and the fluidizing cooling section 200, a plurality of layers of replacement air gas distribution assemblies 6 are sequentially set from top to bottom inside the gravity cooling section 300.

[0174] At the same time, a small amount of dry gas or dry cold gas is introduced into the gravity cooling section 300 by using the replacement wind gas distribution component 6 to bring a small amount of moisture in the gas between the material particles out of the shell body 1, so that the material remains in a dry cold gas environment.

[0175] The present invention has the following beneficial effects when processing powdery and granular products, especially when processing products produced by fermentation plants that are easy to absorb moisture and agglomerate:

[0176] 1. The violent turbulence and back-mixing characteristics of fluidization are used to strongly disperse and crush the wet materials, and the strong flushing effect on the shell and the wall of the heat exchanger is used to effectively solve the problems of moisture absorption, agglomeration, and scarring of the heat exchange plate (or tube) surface during the drying or cooling process, especially the first and second heat exchanger components in contact with the materials above, thereby ensuring the long-term stable operation of the equipment without blockage, scarring, and unchanged heat exchange efficiency, and the material itself has no agglomerates during the cooling process.

[0177] 2. The high heat / mass transfer rate of fluidized drying is used to intensify the drying process and improve the drying / cooling capacity per unit cross-sectional area, thereby increasing the production capacity per unit area or increasing the moisture content of the feed to expand the application range of the material.

[0178] 3. By utilizing the high turbulence and high back-mixing characteristics of fluidization, the feed cone and the segregation phenomenon of the feed process are eliminated, so that the material is evenly distributed in the cross section of the shell body. The entire gravity cooling process is uniform and consistent, and the cooling temperature is further reduced, so that a product with lower temperature, more uniform temperature and moisture content, and no moisture absorption can be obtained, thereby effectively solving the problem of product hardening during the storage and transportation period.

[0179] 4. The functions of material drying or deep drying, moisture uniformity and deep cooling are completed in the same equipment, which expands the performance of the equipment.

[0180] 5. Reduce the height-to-diameter ratio of the equipment. Drying or deep drying functions can still be achieved at a lower height-to-diameter ratio, while ensuring a uniform and consistent deep cooling effect. Or a larger cross-section can be used at the same height while ensuring drying / cooling effects, thereby increasing equipment capacity. Reducing the height of the equipment also reduces equipment and plant investment.

[0181] In this embodiment, the implementation effect of drying and cooling a 70% lysine fluidized bed granulation product is given. The feed is a hot material of qualified particle size that has been screened and discharged from the granulation fluidized bed system. The drying and cooling integrated machine of the present invention is used to replace the original fluidized bed drying / cooling machine to perform deep drying and deep cooling operations on the material, thereby obtaining a final product with qualified particle size, moisture and temperature. The incoming material flow rate is 6.5t / h, the particle size range of the incoming material is 0.6-1.7mm, the average particle size is 1.1mm, the initial moisture is 2.5-3%, the temperature is 75~85℃, and the moisture content of the product is required to be ~2%, and the temperature is 25~30℃. The critical fluidization velocity calculated according to the average particle size of the particles is ~0.21m / s (varies with parameters such as air temperature and pressure). Its drying / cooling structure, process parameters and effects are as follows:

[0182] 1. The entire box can be divided into four sections according to the different environments in which the materials are located, namely, fluidized drying section, fluidized cooling section, gravity cooling section and discharge section. The fluidized drying section is a deep drying section for the materials, and the fluidized cooling section is a high-temperature cooling section for the materials, and its interior is provided with a layer of drying heat exchanger assembly 2, a layer of first fluidized wind gas distribution assembly 4, a layer of cooling heat exchanger assembly 3 and a layer of second fluidized wind gas distribution assembly 5 from top to bottom; the gravity cooling section is further divided into two layers, namely, a medium-temperature cooling section and a low-temperature cooling section, and its interior is provided with a layer of cooling heat exchanger assembly 3, a layer of replacement wind gas distribution assembly 6, a layer of cooling heat exchanger assembly 3 and a layer of replacement wind gas distribution assembly 6 from top to bottom; the discharge section is an inverted conical discharge hopper, and its lower discharge port 103 is connected to the discharger 9. The rest of the description is omitted.

[0183] 2. The fluidizing air or replacement air provided by all gas distribution components are dry air after the ambient air is dehumidified by gas dehumidification equipment, with a dew point temperature of 0~5℃; part of the gas is heated by the gas heating equipment to become hot dry air of 100~150℃, and is sent to the fluidizing drying section 100 through the first fluidizing air gas distribution component 4; the remaining gas is cooled by the gas cooling equipment to become cold dry air of 20~25℃, and then sent to the fluidizing cooling section 200 (high-temperature cooling section) through the second fluidizing air gas distribution component 5, or is simultaneously sent to the gravity cooling section 300 (medium-temperature cooling section and low-temperature cooling section) through the replacement air gas distribution component 6.

[0184] 3. The deep drying section adopts steam and hot air combined heating. The drying heat exchanger assembly 2 adopts a tubular heat exchanger, the serpentine heat exchange tube specification is φ25*3, the heat source is 0.5~0.6Mpa, 180℃ superheated steam, which is sent into the heat exchanger after adjusting the flow or pressure through the regulating valve, and its heat transfer coefficient can reach 100~150w / m 2, providing the main heat required for drying. The inlet distribution main pipe of the heat exchanger is at the top and the outlet distribution main pipe is at the bottom, operating in parallel with the material flow. The 70~75℃ hot dry air from the fluidized cooling section 200 and the gravity cooling section 300 after heat exchange with the material is combined with the 100~150℃ hot dry air introduced through the first fluidized air gas distribution component 4, and is used to fluidize the material layer, provide part of the heat and take away the steam generated during the drying process. When the ventilation volume of the first fluidized air gas distribution component 4 is calculated separately, the corresponding operating wind speed is generally not less than 0.1m / s, and the corresponding fluidization number is not less than 0.5. The sum of the ventilation volumes of all dry air coming up from the bottom generally corresponds to an operating wind speed of not less than 0.4m / s, and the corresponding fluidization number is not less than 2, so that the material layer is in a good fluidization state, which can effectively eliminate the feed cone and feed segregation phenomena. In order to improve the heating capacity of hot air, without excessive entrainment, the operating wind speed calculated based on the ventilation volume of the first fluidizing air gas distribution component 4 can be increased to 0.8m / s, and the corresponding fluidization number can reach 3.8. The operating wind speed after being combined with the lower incoming wind can reach more than 1.1m / s, and the corresponding fluidization number can reach 5.2. Since the incoming material is screened material with fewer fine particles, the entrainment amount is not large at this fluidization speed, and it is conducive to further removing the fine powder in the product and improving the product quality.

[0185] 2. The cooling heat exchanger components 3 of the three-layer cooling section all use plate heat exchangers, and the refrigerant is water. The inlet distribution main pipe of the heat exchanger is at the bottom, and the outlet distribution main pipe is at the top, and it operates in countercurrent with the material flow. The material in the high-temperature cooling section is in a fluidized state, and is cooled by a combination of cooling water and fluidizing air (a small amount of displacement air is added when the displacement air is turned on). The cooling water inlet temperature of the cooling heat exchanger component 3 is controlled at 30-35°C, which reduces the heat transfer temperature difference between the material and the refrigerant while also avoiding excessive relative humidity of the air, which may cause the material to form scars on the wall of the cooling heat exchanger component 3 or the particles to absorb moisture or condense on the surface to form a crust; in the bed layer of the fluidized cooling section 200, when all the displacement air gas components are in the closed state, the air volume required for fluidization comes entirely from the second fluidizing air gas distribution component 5, and the fluidizing air velocity generated is 0.32-0.6m / s, and the fluidization number is 1.5-2.9 When the replacement wind gas component is turned on, the total air volume of fluidizing air and replacement air remains unchanged, that is, the fluidization number generated by the total air volume is still between 1.5 and 2.9. At this time, the fluidization wind speed calculated separately according to the ventilation volume of the second fluidizing wind gas component 5 is reduced to 0.21m / s, and the corresponding fluidization number is about 1, thereby ensuring that the materials under both working conditions are evenly and fully in a bubbling fluidized state, bringing out the water vapor contained in the air in the material gap, and avoiding local material flow blockage; when the fluidization number is between 1.5 and 2.9, the heat transfer efficiency between the fluidized material and the heat exchange wall is also high, and the scouring of the heat exchange wall by the material in the fluidization also prevents or reduces the wall scarring.

[0186] The cooling water inlet temperature of the cooling heat exchanger assembly 3 in the medium temperature cooling section is controlled at 22-25°C to obtain a relatively ideal cooling effect while avoiding scarring; at the same time, replacement air is introduced, and the operating wind speed is 0.05-0.1m / s, so that the material is in a fluidization number between 0.24 and 0.48, and the water vapor in the gap between the materials is taken out to maintain a dry air environment, while ensuring that the material is in an aerated state to improve the fluidity of the material. Because the fluidity of 70% lysine particles is good, and the moisture in the material has been fully replaced in the high temperature cooling section, the replacement air can also be not introduced in the dry season to save air volume.

[0187] The cooling water inlet temperature of the cooling heat exchanger assembly 3 of the low-temperature cooling section is controlled at 8-20°C, and a deep cooling effect of 25-30°C or below can be obtained. At this time, the material has been cooled to a temperature close to the discharge temperature, the heat transfer temperature difference between the material and the refrigerant is low, the material is in a fully dry and cold environment, and there is basically no moisture or condensation on the material. Generally, there is no need to ventilate the replacement air. The replacement air can also be turned on according to the material and weather conditions. If the replacement air is turned on, the operating wind speed is similar to or lower than that of the medium-temperature cooling section. However, when the two replacement air gas assemblies are turned on, the operating wind speed generated by the sum of the ventilation volume is not easy to exceed the fluidization number 0.5.

[0188] The effect is as follows:

[0189] (1) In actual application, during the hot and humid weather period in summer and autumn, the drying and cooling integrated machine of this embodiment can reduce the average moisture content of the material from 2.5-3.0% at the inlet to ~2% at the outlet, with an average moisture reduction of 0.5-1.0%, of which the particles larger than the average particle size have a moisture reduction of about 0.5-1.0%, and the particles smaller than the average particle size have a moisture reduction of about 0.2-0.5%, thus playing a role in moisture homogenization; while reducing the moisture content, the material temperature is cooled to ~25°C, which is lower than the average temperature of the hottest month in summer, and the temperature difference of the material after cooling is very small. The system can run continuously for more than 60 days without material agglomeration and scarring on the heat exchanger; the cooling effect is stable and continuous.

[0190] The above deep drying and deep cooling effects, together with strict control measures on moisture absorption during downstream transportation and packaging, basically eliminate the compaction phenomenon of 70% lysine granular packaging products during long-term storage in summer and autumn.

[0191] (2) Improved product quality. During fluidized drying and fluidized cooling (high-temperature cooling), a small amount of fine powder in the material can be further selected by air separation; during medium-temperature and low-temperature cooling, the material particles flow slowly and controllably, effectively preventing the wear and breakage of the product, and almost no fine powder is generated during the cooling process; during medium-temperature and low-temperature cooling, the material is cooled mainly by indirect heat transfer, and the material is in a dry cold air environment and basically does not come into contact with the ambient air, thus avoiding the increase of the water content of the product during the cooling process; the deep dehumidified dry cold air can even make the moisture distribution of the material more uniform and further reduce the moisture content.

[0192] (3) The drying and cooling process is less than 3000m 3 / h of tail gas emissions, compared with the fluidized bed deep drying / cooling process 25000m 3 / h of tail gas emissions, reduced by more than 85%, and significantly reduced emissions; the tail gas is merged into the large amount of tail gas discharged from the granulation bed for dust removal and deodorization, without the need for separate equipment.

[0193] (4) High energy efficiency. Due to the use of cooling water for indirect heat exchange, the dehumidification and cooling steps of air cooling are omitted. In summer, the consumption of ice water is reduced from 120m 3 / h reduced to 35m 3 / h, saving about 70%.

[0194] By utilizing the gravity flow of the material itself, a large amount of fluidizing air pressurization and negative pressure suction links as well as equipment operation links are eliminated. The installed power of the entire system is reduced from 125kw to 30kw, and power consumption is saved by about 75%.

[0195] (5) Fluidized bed drying / cooling machine and its auxiliary equipment such as bag filter, blower and exhaust fan occupy an area of ​​200m 2 The drying and cooling integrated machine eliminates the need for large equipment such as bag dust collectors and blowers, and has fewer ancillary equipment, occupying an area of ​​only 60m 2 Within 10 days, 70% can be saved, thus saving equipment and plant investment.

[0196] Example 2

[0197] like Figure 2 As shown, the difference from Example 1 is that an expansion section 107 is provided above the shell body 1. Specifically, the lower shell of the feed section is a shell with a rectangular cross section, the upper shell is a shell with an expanded rectangular cross section, and the shell between the upper and lower shells is a gradually expanding frustum-shaped shell. A first fluidizing air gas distribution assembly 4 is provided on both the upper and lower sides of the drying heat exchanger assembly 2.

[0198] In this embodiment, two layers of first fluidizing air gas distribution components 4 can be used to dry the fed materials at the same time, thereby increasing the moisture content of the feed, expanding the applicable range of the materials, or reducing the requirements for the final moisture content of the raw material pre-drying, and further improving the quality of the product. The explanation is as follows:

[0199] By introducing a large amount of hot gas or hot dry gas into the first fluidized air gas distribution component 4 on the upper side, the fluidized air velocity corresponding to the flow of the introduced gas plus the total amount of gas from the lower part can even reach a fluidization number of 5 to 15, so that the material layer in the feed bin is in a violent fluidized state, forming a fluidized bed layer of a certain thickness, while eliminating the feed cone and segregation phenomenon, using the large amount of heat energy provided by the high-temperature hot air to pre-dry a large amount of water. Due to the large amount of water removed and the high inlet temperature, the inlet air can even use undehumidified gas; and when the material is in the high-humidity stage, the tendency of agglomeration and scarring is relatively large. The high turbulence and high back-mixing characteristics of the material in the fluidization have a good dispersion and block breaking effect on the wet material. After the moisture content of the material is reduced, its own agglomeration and scarring characteristics are also reduced accordingly, which is conducive to reducing the agglomeration and plate formation of the material when it enters the drying heat exchanger section. Compared with the first fluidized air gas distribution component on the lower side, the material layer above the first fluidized air gas distribution component on the upper side is lower, and the power consumption required for a large amount of air supply is also less, thereby reducing the energy consumption required for air supply.

[0200] In coordination therewith, a small amount of hot gas or hot dry gas is introduced into the first fluidizing air gas distribution assembly 4 on the lower side, but the materials in the heat exchanger area are still in a good fluidized state. The corresponding fluidization number is greater than 1. While the high heat and mass transfer rate in the fluidized state is utilized to efficiently dry the materials, undesirable phenomena such as material agglomeration or scarring on the heat exchanger wall are avoided.

[0201] In coordination with this, when the hot air is introduced into the second-layer first fluidized air gas distribution assembly 4 for material drying, the gas flow rate is very large, so the feed section is often set as a shell with an expanded section, that is, the lower shell of the feed section is a shell with a rectangular cross section, the upper shell is a shell with an expanded rectangular cross section, and the upper and lower shells are a gradually expanded cone-shaped shell. When the material is in the working state, it is usually located in the lower shell, and there is a cone-shaped shell with a certain height and a rectangular upper shell above the material layer as a gas-solid separation space. Since the wind speed of the exhaust gas gradually decreases during the rising process, more small particles entrained in the exhaust gas will settle back to the material layer in this space, so that only fine powder is taken away from the exhaust gas, so it can work at a higher fluidization speed without increasing the amount of particles entrained by the exhaust gas.

[0202] In this embodiment, the deep drying / cooling process of the 70% lysine fluidized bed granulation product exemplified in Example 1 is still taken as an example, and the operating parameters and implementation effects thereof are improved over those in Example 1 as follows:

[0203] 1. The ventilation volume of the first fluidized air gas distribution component 4 on the lower side of the drying heat exchanger component 2 plus the sum of all ventilation volumes from the lower shell, the fluidized wind speed generated in the material layer area where the drying heat exchanger component 2 is located is generally about 0.4m / s, and the corresponding fluidization number is about 1.9, which has made the material layer in a good fluidized state, so there is no need to further increase the air volume. At the same time, the fluidized wind speed generated by the ventilation volume of the first fluidized air gas distribution component 4 on the upper side of the drying heat exchanger component 2 is as high as 0.6~1.1m / s, and the corresponding fluidization number is 2.9~5.2. The fluidized wind speed corresponding to all the air volumes passing through the material layer above it is 1.0~1.5m / s, and the corresponding fluidization number is about 4.8~7.1, and the corresponding bed height is 500~700mm. In contrast, the bed height required for the ventilation of the first fluidized air gas distribution component 4 on the lower side is more than 2000mm, which can save more than 15kw of power consumption from the perspective of energy saving. Since it adopts an expanded section design, the cross-sectional area of ​​the expanded section is twice that of the lower straight section. Therefore, the wind speed of the expanded section does not increase, and the exhaust gas entrainment amount does not increase.

[0204] 2. Since the air volume of the drying section is increased, the material layer is in a violent fluidized state, and there is no heat exchanger on the first fluidized air gas distribution component 4 on the upper side, there is no need to worry about the problem of scarring, and the feed moisture is increased from 2.5~3% to about 4%. The fluidized bed granulator (granulation bed) used in the 70% lysine granulation production can generally be divided into a granulation drying section and a deep drying section. The deep drying section is used to reduce the moisture content of the granules after granulation and drying from about 5% to 2.5~3% and then discharge the granulation bed. In Example 2, due to the increase in the feed moisture content of the fluidized drying section 100, the final moisture requirement of the discharge of the deep drying section of the granulation bed can be significantly reduced, thereby reducing the tail gas temperature of the granulation bed, while avoiding excessive drying of particles outside the qualified particle size in the granulation bed (the yield of the granulation bed discharge is generally 40%~70%), saving energy consumption.

[0205] Example 3

[0206] like Figure 3 As shown, the difference from Example 1 is that this embodiment can be expanded as follows: multiple layers of drying heat exchanger components 2 can be arranged in series in an up-and-down manner in the fluidized drying section 100, and each layer of drying heat exchanger components 2 includes multiple heat exchangers 31 arranged in parallel.

[0207] When steam heat source is used, heat is supplied in parallel, that is, steam is independently connected from the heat source main pipe to the heat source inlet main pipe of each heat exchanger, and condensed water generated during the heat exchange process is independently connected to the condensed water main pipe. When hot water, heat transfer oil and other heat sources are used, heat can be supplied in series, that is, the heat source enters from the heat source inlet distribution main pipe at the bottom, enters the multi-layer drying heat exchanger assembly 2 in series in sequence, and finally is discharged from the heat source outlet distribution main pipe at the top to increase the total temperature difference between the heat source inlet and outlet and reduce the heat source flow rate; it can also be supplied in parallel like the steam heat source to increase the temperature difference between the heat source and the material and further reduce the final moisture content of the material.

[0208] When multiple layers of drying heat exchanger components 2 and cooling heat exchanger components 3 are provided, the tube heat exchanger and the plate heat exchanger can be used in different drying sections or cooling sections. Preferably, the heat exchange tubes or heat exchange plates of all layers extend in the same direction in the horizontal direction, and the heat exchange tube groups or heat exchange plate groups of the upper and lower adjacent heat exchanger components are arranged alternately in the vertical direction. Figure 8 The staggered arrangement of the heat exchange tubes shown in FIG. Fig. 9 The staggered arrangement of the heat exchange plates shown in the figure can also be used when the tube heat exchanger and the plate heat exchanger are adjacent to each other. Figure 5 As shown in the staggered arrangement, the material flowing downward in the first material channel 1000 formed between adjacent heat exchange tubes or adjacent heat exchange plates of the previous heat exchanger assembly can be distributed to two adjacent first material channels 1000 when entering the next heat exchanger assembly, thereby increasing the lateral movement of the material, breaking the slight adhesion between the materials, increasing the mixing of materials at different temperatures, and improving the temperature uniformity of the materials.

Claims

1. A drying and cooling integrated machine, characterized in that: It comprises a shell body (1), a drying heat exchanger assembly (2), a cooling heat exchanger assembly (3), a gas distribution assembly, a gas supply system and a heat exchange medium supply system; The drying heat exchanger assembly (2) and the cooling heat exchanger assembly (3) are plate heat exchangers or tube heat exchangers, and a first material channel (1000) penetrating vertically is provided between the heat exchange plates or between the heat exchange tubes of the drying heat exchanger assembly (2) and the cooling heat exchanger assembly (3); The gas distribution assembly comprises an air distribution channel (2000) distributed along the cross section of the shell body (1); second material channels (3000) are arranged on the outside of the air distribution channel (2000) and are distributed along the cross section of the shell body (1) at intervals from each other; and air distribution holes (4000) are arranged on the side wall of the air distribution channel (2000) and are communicated with the inner cavity of the shell body (1); The shell body (1) is a vertical shell, the top of the shell body (1) is provided with a feed inlet (101) and an exhaust port (102), and the bottom of the shell body (1) is provided with a discharge port (103); The shell body (1) is provided with a fluidized drying section (100), a fluidized cooling section (200) and a gravity cooling section (300) from top to bottom; The fluidized drying section (100) is provided with a drying heat exchanger assembly (2) connected to a heat exchange medium supply system; The fluidized cooling section (200) and the gravity cooling section (300) are provided with a cooling heat exchanger assembly (3) connected to a heat exchange medium supply system; The heat exchange medium supply system is used to provide heat medium and cold medium to the drying heat exchanger component (2) and the cooling heat exchanger component (3) respectively; The gas distribution assembly comprises a first fluidizing air gas distribution assembly (4) and a second fluidizing air gas distribution assembly (5) respectively arranged in the fluidizing drying section (100) and the fluidizing cooling section (200), wherein the first fluidizing air gas distribution assembly (4) and the second fluidizing air gas distribution assembly (5) are respectively connected to a gas supply system; The first fluidizing air gas distribution component (4) is used to introduce hot dry gas or hot gas that has not been dehumidified by a gas dehumidification device into the shell body (1), and its ventilation volume simultaneously merges with the ventilation volume of the second fluidizing air gas distribution component (5), so that the material in the fluidized drying section (100) is in a fluidized state; The second fluidizing air gas distribution assembly (5) is used to introduce dry gas into the shell body (1) so that the material in the fluidizing cooling section (200) is in a fluidized state.

2. The drying and cooling integrated machine according to claim 1, characterized in that: When the first fluidizing air gas distribution component (4) and the second fluidizing air gas distribution component (5) are working simultaneously, the fluidizing air velocity generated by the ventilation volume of the second fluidizing air gas distribution component (5) is not less than 1 times the critical fluidizing velocity calculated according to the average particle size of the material; the fluidizing air velocity generated by the sum of the ventilation volumes of the first fluidizing air gas distribution component (4) and the second fluidizing air gas distribution component (5) is not less than 1.5 times the critical fluidizing velocity calculated according to the average particle size of the material; The fluidizing wind speed generated by the sum of the ventilation volumes of the first fluidizing wind gas distribution assembly (4) and the second fluidizing wind gas distribution assembly (5) is not higher than 15 times the critical fluidizing speed calculated based on the average particle size of the material.

3. The drying and cooling integrated machine according to claim 1, characterized in that: The fluidized cooling section (200) and the gravity cooling section (300) are provided with more than two layers of cooling heat exchanger components (3) from top to bottom, each layer of cooling heat exchanger components (3) forms a cooling section, and the temperature of the refrigerant in each layer of cooling heat exchanger components (3) decreases sequentially from top to bottom.

4. The drying and cooling integrated machine according to claim 1 or 3, characterized in that: Each layer of drying heat exchanger components (2) and cooling heat exchanger components (3) adopts an independent heat exchange medium supply system, and the heat exchange medium supply system can independently control the flow rate and / or pressure and / or temperature of the heat exchange medium in the heat exchanger components connected thereto.

5. The drying and cooling integrated machine according to claim 3, characterized in that: The gas distribution assembly further comprises a replacement air gas distribution assembly (6) disposed in the gravity cooling section (300) and connected to the gas supply system; The replacement air gas distribution assembly (6) is used to introduce dry gas into the shell body (1); A layer of replacement air gas distribution component (6) is provided below each layer of cooling heat exchanger components (3) in the gravity cooling section (300).

6. The drying and cooling integrated machine according to claim 5, characterized in that: When the replacement air distribution component (6) is partially or fully operational, the ventilation volume or the sum of the ventilation volumes of the replacement air distribution component (6) generates an operating air velocity that is 0 to 0.5 times the critical fluidization velocity calculated based on the average particle size of the material; When the first fluidizing air gas distribution component (4), the second fluidizing air gas distribution component (5) and the replacement air gas distribution component (6) are working simultaneously, the operating air speed generated when the ventilation volume of the second fluidizing air gas distribution component (5) is calculated alone is not less than 0.7 times the critical fluidizing speed calculated according to the average particle size of the material; the fluidizing air speed generated by the sum of the ventilation volumes of the second fluidizing air gas distribution component (5) and the replacement air gas distribution component (6) is not less than 1.2 times the critical fluidizing speed calculated according to the average particle size of the material; the fluidizing air speed generated by the sum of the ventilation volumes of the first fluidizing air gas distribution component (4), the second fluidizing air gas distribution component (5) and all the replacement air gas distribution components (6) is not higher than 15 times the critical fluidizing speed calculated according to the average particle size of the material.

7. The drying and cooling integrated machine according to claim 1, characterized in that: It also comprises an auxiliary material bin (7), the inlet of the auxiliary material bin (7) being connected to the discharge port (103), and the outlet of the auxiliary material bin (7) being connected to the feed port (101).

8. The drying and cooling integrated machine according to claim 1, characterized in that: It also includes a material level meter (8) and a discharger (9) with adjustable flow rate; The material level meter (8) is arranged on the top of the shell body (1) and is used to measure the material level height of the material in the shell body (1); The discharger (9) is connected to the discharge port (103) and is used to adjust the discharge speed of the material so as to control the material level height in the shell body (1).

9. The drying and cooling integrated machine according to claim 5, characterized in that: The gas supply system includes a gas dehumidification device, a gas heating device and a gas cooling device, and the heat exchange medium supply system includes a fluid pressure / flow control device or a fluid heating device and a fluid cooling device; The gas dehumidification equipment is used to remove moisture from the gas to obtain dry gas, and the gas cooling equipment is used to control the temperature of the dry gas entering the fluidized cooling section (200) and the gravity cooling section (300); The gas heating device is used to heat the dry gas entering the fluidized drying section (100) or the gas that has not been dehumidified by the gas dehumidification device; The fluid pressure / flow control device is used to control the pressure or flow of the heating medium or the cooling medium; The fluid heating device is used to heat the liquid heat medium; The fluid cooling device is used to control the temperature of the refrigerant to prevent the material from absorbing moisture, agglomerating or forming scars on the wall of the heat exchanger.

10. The drying and cooling integrated machine according to claim 1, characterized in that: The drying heat exchanger assembly (2) or the cooling heat exchanger assembly (3) comprises a plurality of heat exchange tubes arranged at intervals in a horizontal direction, wherein the heat exchange tubes are serpentine tubes extending up and down; Two adjacent serpentine heat exchange tubes are arranged in an up-and-down staggered manner.

11. The drying and cooling integrated machine according to claim 1, characterized in that: The drying heat exchanger assembly (2) is a tubular heat exchanger.

12. The drying and cooling integrated machine according to claim 1, characterized in that: The first fluidizing air gas distribution assembly (4), the second fluidizing air gas distribution assembly (5) and the replacement air gas distribution assembly (6) each comprise a plurality of gas distribution pipes (10) arranged horizontally and spaced apart from each other, and air distribution holes (4000) are arranged below the gas distribution pipes (10); The air distribution holes (4000) are arranged in rows at intervals along the axial direction of the gas distribution pipe (10), and at least one row of air distribution holes (4000) is arranged below each gas distribution pipe (10); The gas distribution pipe (10) is a straight pipe, and the gas distribution pipe (10) and the heat exchange pipes in the drying heat exchanger assembly (2) or the cooling heat exchanger assembly (3) are perpendicular to each other, or the gas distribution pipe (10) and the heat exchange plates in the drying heat exchanger assembly (2) or the cooling heat exchanger assembly (3) are perpendicular to each other.

13. A drying and cooling method, using the drying and cooling integrated machine according to any one of claims 1 to 12, characterized in that: The following steps are involved: S1. Using dried and cooled materials, the drying heat exchanger assembly (2) and the cooling heat exchanger assembly (3) in the shell body (1) are completely buried to a preset height above the drying heat exchanger assembly (2); S2, using the first fluidizing air gas distribution component (4) to introduce hot dry gas or hot gas that has not been dehumidified into the shell body (1), and using the second fluidizing air gas distribution component (5) to introduce dry gas or dry cold gas into the shell body (1), so that the material above the first fluidizing air gas distribution component (4) and the second fluidizing air gas distribution component (5) is in a fluidized state, ensuring that the material is evenly distributed in the cross section of the shell body (1), and enters the gravity cooling section (300) in this evenly distributed state; S3, using the drying heat exchanger assembly (2) of the fluidized drying section (100) to heat and dry the material, and at the same time using hot dry gas to heat and dry the material under fluidization, fully replacing the moist gas between the material particles, and bringing the moisture precipitated in the material and in the moist gas out of the shell body (1); Alternatively, the material is heated and dried using hot gas that has not been dehumidified under fluidization, so that moisture precipitated from the material is taken out of the shell body (1); S4. At the same time, the material is cooled using the cooling heat exchanger components (3) of the fluidized cooling section (200) and the gravity cooling section (300); At the same time, dry gas is introduced into the fluidized cooling section (200) by using the second fluidizing air gas distribution assembly (5) to fluidize the material, fully replace the moist gas between the material particles with the dry gas, and bring the moisture in the moist gas and the moisture precipitated in the material out of the shell body (1); The refrigerant inlet temperature of each cooling heat exchanger assembly (3) is controlled to be higher than the temperature at which the material on the material side of the corresponding cooling heat exchanger assembly (3) absorbs moisture, agglomerates, or forms scars on the heat exchanger wall.

14. The drying and cooling method according to claim 13, characterized in that: In step S1, the method of using materials to completely bury the drying heat exchanger assembly (2) and the cooling heat exchanger assembly (3) in the shell body (1) is: S11, a first fluidizing air gas distribution assembly (4) and a second fluidizing air gas distribution assembly (5) are arranged at the upper end of the shell body (1), and before drying and cooling the material, the dried and cooled material is quickly added into the shell body (1) to a preset height; S12, while the material is being added, when the material level reaches the second fluidizing air gas distribution component (5) of the fluidized cooling section (200), the second fluidizing air gas distribution component (5) is started and gas is introduced so that the material above the gas distribution component enters a fluidized state; S13, when the material level reaches the first fluidizing air gas distribution component (4), the corresponding first fluidizing air gas distribution component (4) is opened at the same time, and gas is introduced until the material layer reaches the material level of normal production. During the whole process, the material above the second fluidizing air gas distribution component (5) is in a fluidized state; until the material level reaches a preset height, and finally a fluidized drying section (100), a fluidized cooling section (200) and a gravity cooling section (300) are formed in an upper and lower arrangement; According to the requirements, the gas introduced into the second fluidizing air gas distribution component (5) may be dry gas or dry cold gas; the gas introduced into the first fluidizing air gas distribution component (4) may be hot dry gas or hot gas that has not been dehumidified; S14. Next, the material to be dried and cooled is continuously fed into the shell body (1) from the feed inlet (101) at the top of the shell body (1).

15. The drying and cooling method according to claim 13, characterized in that: The step S5 is also included: On the basis of respectively arranging a first fluidizing air gas distribution assembly (4) and a second fluidizing air gas distribution assembly (5) in the fluidized drying section (100) and the fluidized cooling section (200), a plurality of layers of replacement air gas distribution assemblies (6) are sequentially arranged from top to bottom inside the gravity cooling section (300); At the same time, a small amount of dry gas or dry cold gas is introduced into the gravity cooling section (300) by using the replacement wind gas distribution component (6) to bring a small amount of moisture in the gas between the material particles out of the shell body (1), so that the material remains in an environment of dry cold gas.

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