Drying and cooling all-in-one machine

Abstract

The utility model belongs to the field of powder material processing, and particularly relates to a drying and cooling all-in-one machine, which is characterized in that a fluidized drying section, a fluidized cooling section and a gravity cooling section are arranged in a shell body from top to bottom, so that materials in the fluidized drying section and the fluidized cooling section are in a fluidized state; by means of the arrangement, materials fed from the feeding port are rapidly spread in the horizontal direction, even particle distribution is formed in the cross section of the shell body, the materials downwards, evenly and integrally pass through the gravity cooling section, and uneven cooling caused by material segregation and different cooling speeds of all the materials is eliminated; the high heat and mass transfer rate brought by material fluidization is utilized, and the materials are efficiently dried in the drying section; and damp and hot gas can be effectively replaced in the fluidization cooling section, so that material scabbing is avoided. After the material subjected to fluidized drying, cooling and dry gas replacement enters the gravity cooling section, a refrigerant with lower temperature can be adopted for cooling, and meanwhile, the cooling efficiency and the cooling effect are improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of powder material processing, concretely relates to a drying and cooling all-in-one machine. BACKGROUND

[0002] Obtaining products by microbial fermentation is one of the main production methods in bio-chemical industry. Because of the complex composition of fermentation broth containing various organic and inorganic metabolites, various impurities are inevitably contained in the main and by-product obtained by the post-processing of the crude fermentation broth, which leads to the phenomenon of sticking and hardening of the product during storage and transportation, reduces the quality of the product, and increases the cost of transportation and fertilization. The crystalline product produced by fermentation often contains crystal water, has poor stability under pressure or heat, or has hygroscopic properties, so that the mutual fusion phenomenon occurs between the particles during long-term storage, which also easily leads to the same problem.

[0003] Generally, the powder and granular products of fermentation plants need to be dried to the qualified moisture by different forms of dryers first, and then cooled to near room temperature by fluidized bed, rotary cylinder and other cooling equipment before packaging. However, for the fluidized bed, rotary cylinder and other cooling equipment, since the air directly contacts the material, the moisture will also enter the material from the air while the material is being cooled; or due to incomplete cooling process of the material, heat and moisture will migrate between the inside and surface of the material particles after cooling is completed, and between the surface of the particles and the air in the surrounding gap, etc., ultimately leading to caking, hardening and other phenomena. In order to avoid product caking, the current tendency is to reduce the moisture content of the product to far below the equilibrium moisture under ambient conditions in the drying link, and based on the characteristics of the fermentation product being easy to absorb moisture, the ambient air, especially the ambient air in the hot and humid season, is used as the coolant. While cooling the material, the moisture in the air will also enter the material, causing the material to absorb moisture; there are certain gaps between the particles of bulk material, and the humid air filling the gaps will enter the closed environment of the packaging bag, and the moisture absorption process on the surface of the particles will also cause the particles to further stick together; and 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 continue to be released into the gap during the continuous heat dissipation process of the material to the environment, which will also continue to increase the humidity of the air, and further cause the particles to stick together. Therefore, for the equipment that directly contacts the material with air for cooling, the air needs to be deeply dehumidified to avoid the material absorbing moisture during the cooling process, and the air in the gap of the material particles is replaced with dry air; due to the efficiency problem of the cooling equipment, in order to cool the material to the ambient temperature (such as cooling the material to below 25-35℃ in summer), a lower inlet air temperature and a lower relative humidity at the inlet air temperature (such as: dry bulb temperature 20℃, relative humidity 20%) are required, but the air is humid in summer and autumn, and the energy consumption of the dehumidification and cooling link is relatively large, sometimes even accounting for more than 20~30% of the energy consumption of the drying process. And during the cooling process, the particles are in a state of intense motion, and the friction between the particles and the wall surface of the cooling equipment will cause the particles to be abraded, new dust generated by friction will enter the product, which will reduce the product quality and increase the degree of product caking.

[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 international sources. Compared with fluidized bed coolers, these devices have significant technological advantages in energy saving, emission reduction, and cooling depth. The main body of this cooling device is a vertically arranged container, divided into three sections from top to bottom: a feeding section, a cooling section, and a discharging section. The cooling section is equipped with a heat exchanger. Free-flowing solid particles enter the container through the inlet of the feeding section and move slowly downwards under gravity. As they flow through the cooling section, they pass through the external channels of the heat exchanger, where heat is carried away by the refrigerant, cooling the material to the required temperature. The material then enters the shell of the discharging section and is discharged from its outlet. Because the material is in a slow, continuous flow state during the cooling process, friction between particles and between particles and the wall is minimal, and particle wear is essentially eliminated. Furthermore, due to the indirect heat transfer method, the material is largely in contact with air, avoiding an increase in the product's moisture content during cooling.

[0005] However, when processing granular products from fermentation plants, whether they are crystalline products or granules produced by granulation and drying of multi-component blends, some common problems exist when using gravity flow coolers for cooling:

[0006] (1) After absorbing moisture, the material is prone to forming scale on the heat exchanger wall, especially the wall of the heat exchanger located above the gravity flow cooler. This will lead to a significant decrease in heat exchange efficiency and may even cause blockage of some material flow channels in severe cases. In addition, the material itself will also form clumps after absorbing moisture.

[0007] (2) In gravity flow coolers, it is generally desirable for the material to flow downwards at a uniform speed across the entire cross-section of the cooler, i.e., to move downwards in a so-called overall flow manner, thereby achieving the best cooling effect. However, the actual application is not always so ideal, especially for materials that are prone to moisture absorption, clumping, and scaling. The clumping and scaling of the material exacerbate the unevenness of the overall flow of the material, resulting in greater differences in the degree of cooling of the material in different areas of different cross-sections of the cooling equipment. This leads to some materials still having a higher temperature, and even if the average discharge temperature meets the requirements, these materials may still caking during long-term storage.

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

[0009] Chinese patent document CN110701927A (201910776877.2) discloses a material cooling system based on a powder flow cooler. The above-mentioned material cooling system can effectively avoid scabbing of the powder flow cooler wall surface and material caking during the cooling process. However, since the above-mentioned material cooling system needs to raise the temperature of the coolant in the powder flow cooler to narrow 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 high temperature, and the material cannot be cooled by a lower temperature coolant, resulting in a decrease in overall cooling efficiency. In addition, after the dry air introduced into the material cooling system absorbs the moisture in the material, it will collect upwards, and the material sent into the material cooling system contains a large amount of hot and humid gas, so the humidity of the upper material at the top of the material cooling system is large. In order to avoid scabbing, the entering temperature of the coolant in the upper powder flow cooler needs to be further increased, causing further decrease in overall cooling efficiency.

[0010] In addition, during the drying and cooling process of the powder material, the material is first dried by a drying device and then enters the cooling section for cooling treatment. The drying and cooling are completed in different devices, which not only brings high energy consumption, but also increases the investment cost due to the large floor area of the equipment.

[0011] Chinese patent document CN104132525A (201410397432.0) discloses a powder material drying and cooling integrated equipment. The equipment is a vertical structure, and has, from top to bottom, a feeding box, a drying box, a cooling box, and a discharging box. The equipment can realize drying and cooling of the powder material in the heat exchange plates, has a small floor area, and has a high heat exchange efficiency. However, the horizontal flow air for drying passes through the material layer in the horizontal direction. When the flow rate of the horizontal flow gas is high, the resistance of the airflow passing through the material layer increases sharply, the flowability of the material after being extruded becomes poor, and local blockage is more likely to occur. Since the drying box and the cooling box are connected to each other, the hot and humid gas between the materials will enter the cooling box together with the hot material. In order to avoid scabbing of the material on the heat exchange plates in the cooling box, the material 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 material and the cooling water. The above problems limit the equipment capacity and stable operation, or the height of the drying box or the cooling box must be increased to increase the equipment capacity or ensure normal operation of the equipment without scabbing, resulting in increase in equipment investment, material loading cost, or the need for a higher factory building. Practical new type content

[0012] The utility model discloses a main purpose is to provide a drying cooling integrated machine, the utility model discloses through setting fluidization drying section, fluidization cooling section and gravity cooling section from top to bottom in the casing body, through the first fluidization wind gas distribution subassembly to the casing body in and import gas ( and add the gas from the fluidization cooling section confluence) in the fluidization drying section, make the material above the first fluidization wind gas distribution subassembly present flow state, thereby make the material sent in from the feed inlet in horizontal direction spread open, and form even particle distribution on the cross section of casing body, eliminate material segregation phenomenon, make the material downward even whole removal through fluidization cooling section, utilize the high heat transfer mass transfer rate that material flow state brought, under the heating of drying heat exchanger subassembly and hot air to the material drying or depth drying, improved the drying efficiency to the material, through the second fluidization wind gas distribution subassembly to the casing body and import dry gas, make the material above the second gas distribution subassembly present flow state, avoid the material scab in the surface of cooling heat exchanger subassembly, utilize the high heat transfer mass transfer rate that material flow state brought and the sufficient mixing contact between particle and gas, can further remove the moisture of wet hot gas and material particle that material took in during drying process in the fluidization drying section, guarantee the material cooling more evenly, and the moisture of material everywhere is more uniform. The material that the particle size distribution is even, moisture is uniform in dry gas environment enters gravity cooling section, passes through gravity cooling section in the whole stream mode, is favorable to cooling heat exchanger subassembly adopts lower temperature coolant to cool the material, reduces the nonuniformity of cooling process, improves cooling efficiency and cooling effect.

[0013] The utility model discloses a drying cooling integrated machine, including casing body, drying heat exchanger subassembly, cooling heat exchanger subassembly, gas distribution subassembly, gas supply system and heat exchange medium supply system, which solves the technical problem of the utility model.

[0014] The drying heat exchanger subassembly and the cooling heat exchanger subassembly are plate heat exchangers or tube heat exchangers, and a first material channel is arranged between the heat exchange plates or the heat exchange tubes of the drying heat exchanger subassembly and the cooling heat exchanger subassembly.

[0015] The gas distribution subassembly is horizontally arranged in the casing body and includes air distribution units and second material channels arranged between the air distribution units.

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

[0017] The casing body is provided with a fluidization drying section, a fluidization cooling section, and a gravity cooling section from top to bottom.

[0018] The fluidization drying section is provided with a drying heat exchanger subassembly connected to the heat exchange medium supply system.

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

[0020] The heat exchange medium supply system is used for supplying hot medium and cold medium to the drying heat exchanger assemblies and the cooling heat exchanger assemblies respectively;

[0021] The gas distribution assemblies comprise first fluidized air gas distribution assemblies and second fluidized air gas distribution assemblies arranged in the fluidized drying section and the fluidized cooling section respectively, and the first fluidized air gas distribution assemblies and the second fluidized air gas distribution assemblies are connected with the air supply system respectively;

[0022] The first fluidized air gas distribution assemblies are used for supplying hot dry gas or hot gas without being dehumidified by the gas dehumidification device into the shell body, and the air volume of the first fluidized air gas distribution assemblies is combined with the air volume of the second fluidized air gas distribution assemblies, so that the material in the fluidized drying section is in a fluidized state, the material entering the fluidized drying section is rapidly spread in the horizontal direction, thereby eliminating the problems of the feed cone and the accompanying feed segregation, and ensuring that the material in the fluidized drying section is uniformly distributed into the fluidized cooling section; the material layer in the fluidized state has higher drying efficiency or lower final moisture content than the slowly moving material layer in the aerated state; when the 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 fluidized air gas distribution assemblies are used for supplying dry gas into the shell body, so that the material in the fluidized cooling section is in a fluidized state; similarly, based on the high heat transfer / mass transfer rate and the sufficient mixing and contact between the particles and the gas caused by the fluidization, the dry gas can be used to more effectively remove the wet hot gas in the gap between the material particles, so that the replaced material is in a uniform and consistent dry gas environment, and the dew point temperature is much lower than the temperature of the cold medium in the cooling heat exchanger assemblies, and therefore a lower temperature cold medium 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 capillaries on the surface of the particles to a certain extent, so that the moisture in the material is further carried out, thereby playing a role of further deep drying.

[0024] In the utility model, the gas supplied by the first fluidized air gas distribution assemblies is hot dry gas or hot gas without being dehumidified; 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 heat state, far away from the equilibrium moisture between the material and the gas, and therefore it is common to use the gas without being dehumidified to dry the material from the perspective of energy saving.

[0025] The dry gas introduced by the second fluidizing air distribution assembly includes dry cold gas, dry normal temperature gas or dry gas with a temperature lower than the temperature of the material leaving the fluidized cooling section; preferably dry cold gas, which has the effect of cooling the material while replacing the dry gas, further improving the cooling efficiency.

[0026] To achieve the above effects, when the first fluidizing air distribution assembly and the second fluidizing air distribution assembly work simultaneously, the flow rate of the second fluidizing air distribution assembly is not less than 1 times (i.e. fluidization number is 1) of the critical fluidization velocity calculated according to the average particle size of the material; the flow rate of the first fluidizing air distribution assembly and the second fluidizing air distribution assembly is not less than 1.5 times (i.e. fluidization number is 1.5) of the critical fluidization velocity calculated according to the average particle size of the material; the flow rate of the first fluidizing air distribution assembly and the second fluidizing air distribution assembly is not more than 15 times (i.e. fluidization number is 15) of the critical fluidization velocity calculated according to the average particle size of the material.

[0027] The fluidization velocity mentioned above refers to the operating air velocity when the material is in a fluidized state (i.e. the actual value of the air velocity during production operation), which is the average operating air velocity passing 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 fluidization velocity (when not reaching the fluidized state, it is the operating air velocity) to the critical fluidization velocity calculated according to the average particle size of the material.

[0028] When the second fluidizing air distribution assembly works, the fluidization velocity of the material in the fluidized cooling section is greater than the fluidization number 1, which makes the material in a fully and uniformly fluidized state, carries out the moisture vapor contained in the gas in the voids of the material, and avoids the situation that the material flow is blocked in local areas. When the second fluidizing air distribution assembly is ventilated, the gas rises and passes through the fluidized cooling section and then enters the fluidized drying section, and the flow rate of the combined ventilation of the first fluidizing air distribution assembly and the second fluidizing air distribution assembly is not less than the fluidization number 1.5, forming a more intense fluidization than the fluidized cooling section, thereby facilitating the rapid elimination of the feed cone, the uniformization of the particle size distribution of the material, and the provision of sufficient air volume to rapidly discharge the moisture generated during the drying process and avoid the moisture of the tail gas reaching the saturation state, causing problems such as scabbing and caking; the increase in air volume also corresponds to the increase in heat, which is conducive to improving the drying efficiency. The fluidization velocity of the material in the fluidized drying section should not exceed the fluidization number 15, because the upper limit of the fluidization velocity is the maximum air velocity for maintaining stable fluidization of the material layer without excessive entrainment, which can be considered by referring to the upper limit of the operating air velocity of a general fluidized bed.

[0029] From the purpose of putting the material in fluidized and flowing state to eliminate the feeding cone, it can be achieved in a certain range of operating air speed from low to high close to the critical fluidization speed (for example, for 70% lysine granulation product, the operating air speed can basically eliminate the feeding cone when the fluidization number is 0.7-1), however, such local and insufficient fluidization cannot meet the requirements of the patent. Because in the device related to the patent, when the operating air speed is determined according to the average particle size, for the material with 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 in the bubbling fluidization state, and the particles with large particle size are still in the static state, and the local fluidization area is randomly distributed in the entire cross section of the box; in the feeding cone area of the upper part of the material layer, due to the driving of the rising bubbles and the flowing particles, the feeding cone of the material pile under the action of its own gravity can be basically eliminated, and the purpose of making the bed layer tend to be basically horizontal is achieved; however, due to the air flow short circuit, local material flow blockage caused by the so-called "local fluidization" or "semi-fluidization", and the structure of uneven distribution of air distribution holes (only distributed at the gas distribution pipe, and the material flow channel between the gas distribution pipe), the humid air in the unfluidized area is more difficult to discharge; the existence of the material moisture absorption and caking characteristics makes the material in the unfluidized area more prone to moisture absorption, caking or scarring. Therefore, in the utility model, it is not desirable that the operating air speed is lower than the fluidization number 1.

[0030] Preferably, the fluidized cooling section and the gravity cooling section are provided with two or more layers of cooling heat exchanger assemblies from top to bottom, each layer of cooling heat exchanger assembly forms a cooling section, and the temperature of the refrigerant of each layer of cooling heat exchanger assembly decreases from top to bottom.

[0031] a.The powder and granular material after drying generally contains a small amount of moisture and has a certain hygroscopicity. In the equilibrium state, the material at a certain temperature corresponds to a certain critical relative humidity of the gas in the gap between the particles and the critical dew point temperature corresponding thereto. When the relative humidity value or the 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 be hygroscopic. In the gravity cooling section, the material layer can be regarded as a fixed bed moving slowly along the fixed flow channel in the aerated state. As the material moves downward, the material temperature gradually decreases, and the corresponding critical relative humidity value and critical dew point value gradually decrease. The material at the end (lower end) of the cooling section at different layers is cooled to a certain temperature, which requires that the coolant 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 humidity and dew point temperature of the gas environment around the particles are lower than the critical value, thereby avoiding material hygroscopicity. However, in the fluidized cooling section, due to the severe backmixing of the material in the upward and downward directions, the temperature difference of the material along the height direction of the bed is reduced to a value near the average temperature of the material (but higher than the equilibrium temperature corresponding to the end of the material in the non-fluidized state), and the same coolant temperature must be higher than this temperature value to avoid material hygroscopicity.

[0032] When dry air with different degrees of dehumidification is supplied to different layers of the cooling section, the material is prevented from being hygroscopic while preventing the gas near the heat exchange wall from being cooled to a temperature close to the wall temperature, and its relative humidity rapidly increases to a saturated state and condenses on the wall to avoid the occurrence of hygroscopicity, caking or scarring on the heat exchange wall or in the local material layer near the wall.

[0033] If a unified temperature coolant is supplied to each layer of the cooling heat exchanger assembly in parallel, the temperature difference between the material and the coolant in the upper to middle cooling section is too large, and based on the above reasons, the probability of hygroscopicity and scarring is large. When the coolant flows countercurrently from bottom to top in series, the temperature rise of the coolant through a single layer of the cooling heat exchanger assembly is still low due to the low heat transfer speed between the material layer and the wall and the large coolant flow, and the temperature difference between the material and the coolant is also large, so the probability of hygroscopicity and scarring is still large. In order to avoid this phenomenon, the fluidized cooling section and the gravity cooling section are divided into multiple cooling sections, i.e., multiple layers of the cooling heat exchanger assembly in the utility model. Each layer of the cooling heat exchanger assembly forms a cooling section, and different temperatures of the coolant are supplied. The material temperature is high at the inlet of the fluidized cooling section, and a higher temperature coolant is supplied to the cooling heat exchanger assembly. As the material temperature decreases, a lower coolant temperature is used, thereby limiting the temperature difference between the material and the coolant to a certain range and avoiding the occurrence of this phenomenon.

[0034] b.Different temperatures of the coolant are supplied to each layer of the cooling heat exchanger assembly. At a higher material temperature, a common coolant with a lower cost, such as circulating water provided by the plant public engineering, is used, and at a lower material temperature, a deep cold water coolant with a higher cost is used, thereby saving production cost.

[0035] The utility model discloses preferably, each layer dry heat exchanger subassembly and cooling heat exchanger subassembly all adopt independent heat exchange medium supply system, the heat exchange medium supply system can independently control and the heat exchange medium flow and / or pressure and / or temperature of the heat exchanger subassembly of its connection. Each layer heat exchanger subassembly sets up independent heat exchange medium supply system, and the flow, pressure, temperature of heat medium and refrigerant can be independently regulated, and the temperature and / or flow of heat medium and refrigerant can be flexibly regulated, guarantee the drying efficiency of dry heat exchanger subassembly and ensure that the refrigerant temperature is higher than the temperature that material absorbs moisture and coagulates, avoid the cooler that cooling heat exchanger subassembly surface scab.

[0036] The utility model discloses preferably, the gas distribution subassembly still includes the replacement wind gas distribution subassembly of setting up in gravity cooling section and with gas supply system is connected;

[0037] The replacement wind gas distribution subassembly is used for leading dry gas into the shell body, makes the material layer be in the aeration state and carries out replacement to the gas in the intergranular gap, carries away the moisture of evaporation (volatilization) in the gas and the particle, reduces the relative humidity and dew point temperature of the gas environment that the particle is at, to can adopt the refrigerant cooling material of lower temperature accordingly, the material in the aeration state can keep good fluidity, makes the material be in the state of whole downward movement in the corresponding cooling section, and the dry gas is preferably dry cold gas, and the effect of cooling material is played simultaneously, and the cooling efficiency is improved;

[0038] Gravity cooling section below each layer cooling heat exchanger subassembly sets up a layer replacement wind gas distribution subassembly.

[0039] In gravity cooling section, multiple layers of cooling heat exchanger subassembly are arranged from top to bottom, and a layer of replacement wind gas distribution subassembly is arranged below each layer of cooling heat exchanger subassembly, which has the following technical significance:

[0040] a. In normal production, the replacement wind gas distribution subassembly can be selected to be not opened, opened, multiple layers or all opened according to the material characteristics and operation requirements, for example, for some materials, a small amount of moisture still evaporates when the material temperature is higher in the upper region of gravity cooling section, and the moisture evaporation stops when the material temperature is lower in the middle and lower regions of gravity cooling section, at this time, the gas distribution subassembly in the upper region should be opened, and the gas distribution subassembly in the lower region does not need to be opened; for some materials, the temperature needs to be cooled to a very low temperature, and more dry gas needs to be supplemented to adapt to the lower temperature refrigerant, at this time, only the gas distribution subassembly in the lower region can be opened; for some materials with poor fluidity, the appropriate aeration state needs to be maintained to increase the fluidity during the entire cooling process, at this time, all the gas distribution subassemblies can be opened to lead in a small amount of dry gas; for materials with good fluidity and no steam separation during the entire process, even no air supply is also available.

[0041] When the multi-layer gas distribution assembly is turned on, the displacement air volume of the cooling section above the position is the sum of the air volumes of all the turned-on gas distribution assemblies below the position, and the fluidization air volume of the material fluidization section is the sum of the air volumes of all the gas distribution assemblies below the position; and the actual operating air speed of the material layer where the material is located (the fluidization air speed in the fluidization section) is generated by all the air volumes of the cross section of the material layer.

[0042] b. In actual application, for materials with less obvious moisture absorption and scabbing characteristics, the gas distribution assemblies (including the second fluidization air gas distribution assembly and the displacement air gas distribution assembly) can be sequentially connected to different dryness degree gases from top to bottom, as long as the dew point temperature is lower than the inlet temperature of the coolant of the cooling section by a certain degree, so as to further save the energy consumption and equipment cost for gas dehumidification. The dryness degree of the dry gas should ensure that the wall surface of the cooling heat exchanger assembly where the coolant at the lowest temperature of the cooling section of the layer is located does not produce condensation, and at the same time, ensure that the material does not appear moisture absorption, caking or scabbing when cooled by the wall surface of the cooling heat exchanger assembly where the coolant at the lowest temperature is located.

[0043] In order to achieve the above effects, when the displacement air gas distribution assembly is partially or fully working, the operating air speed generated by the air volume or the sum of the air volumes of the displacement air gas distribution assembly is 0-0.5 times the critical fluidization speed calculated according to the average particle size of the material.

[0044] When the first fluidization air gas distribution assembly, the second fluidization air gas distribution assembly and the displacement air gas distribution assembly work simultaneously, the operating air speed generated by the air volume of the second fluidization air gas distribution assembly calculated alone is not less than 0.7 times the critical fluidization speed calculated according to the average particle size of the material; the fluidization air speed generated by the sum of the air volumes of the second fluidization air gas distribution assembly and the displacement air gas distribution assembly calculated alone is not less than 1.2 times the critical fluidization speed calculated according to the average particle size of the material; and the fluidization air speed generated by the sum of the air volumes of the first fluidization air gas distribution assembly, the second fluidization air gas distribution assembly and all the displacement air gas distribution assemblies is not higher than 15 times the critical fluidization speed calculated according to the average particle size of the material.

[0045] After the material passes through the upper fluidization cooling section, most of the humid gas has been displaced out of the material gap, and the material is in a relatively dry gas environment, so only a small amount of dry gas needs to be introduced through the displacement air gas distribution assembly to carry out the small amount of moisture volatilized from the material; when a plurality of dry gases with different dryness degrees are selected, the lower displacement air gas distribution assembly can select a gas that is drier than the dry gas introduced by the upper gas distribution assembly, so as to further reduce the dew point of the gas environment in the material gap, and correspondingly, a lower temperature coolant can be used. The dry gas introduced carries out the moisture vapor while also improving the flowability of the material.

[0046] The maximum operating air speed generated by the ventilation volume or the sum of the ventilation volumes in the gravity cooling section is as low as possible when meeting the operating requirements, and the fluidization number is preferably between 0 and 0.5, on the one hand, the resistance of the gas passing through the material layer is very low when the air speed is low, and the power consumption of the gas pressurization is small, on the other hand, when the operating air speed is close to the critical fluidization air speed, the so-called 'local fluidization' or'semi-fluidization' phenomenon occurs, causing gas short circuiting and other defects, which aggravates the gravity flow blockage in the unfluidized area, thereby reducing the cooling effect.

[0047] The utility model discloses preferably still include auxiliary bunker, the import of auxiliary bunker is linked with the discharge port, the export of auxiliary bunker is linked with the feed port.Set up auxiliary bunker for in the process of starting up quick filling shell body, make material reach the material level above heat exchanger subassembly, shorten the process of starting up.And can be used as the temporary storage container when the equipment breakdown overhauls, temporarily store the material after cooling.

[0048] Preferably, the auxiliary bunker is located above the shell body, which can use gravity to send the material into the shell body.

[0049] The utility model discloses preferably still include material level meter and adjustable flow discharge outlet,

[0050] The material level meter is arranged at the top of the shell body and is used for measuring the material level height in the shell body;

[0051] The discharge outlet is connected with the discharge port and is used for adjusting the discharging speed of the material to control the material level height in the shell body. The discharge outlet is used for controlling the uniform discharging of the material, adjusting the flow, and controlling the discharging flow of the discharge outlet through the material level electric signal of the material level meter to control the material level height in the shell body, ensuring a fluidized material layer to maintain stable fluidization, while burying all the heat exchanger assemblies with the material to ensure the heat exchange efficiency and achieve the effect of efficient drying and effectively removing the moisture in the material.

[0052] The utility model discloses preferably, the gas supply system includes gas dehumidification equipment, gas heating equipment and gas cooling equipment, the heat exchange medium supply system includes fluid pressure / flow control equipment or fluid heating equipment, fluid cooling equipment.

[0053] The gas dehumidification equipment is used for removing the moisture in the gas to obtain dry gas, and the gas cooling equipment is used for controlling the temperature of the dry gas entering the fluidization cooling section and the gravity cooling section.

[0054] The gas heating equipment is used for heating the dry gas entering the fluidization drying section or the gas not dehumidified by the gas dehumidification equipment.

[0055] The fluid pressure / flow control device is used for controlling the pressure or flow of the heat medium or the cold medium;

[0056] The fluid heating device is used for heating the liquid heat medium; in the fluidized drying section, the heat medium is not limited to the fluid without phase change heat transfer such as hot water or heat conducting oil, and also includes the fluid with phase change heat transfer such as common water vapor; for the steam, the pressure or flow entering the heat exchanger is controlled through the regulating valve, and for the hot water or heat conducting oil, the temperature and flow control are required;

[0057] The fluid cooling device is used for controlling the temperature of the cold medium to avoid material moisture absorption, caking or scabbing on the wall of the heat exchanger.

[0058] The air distribution unit preferably comprises a gas distribution pipe, and the gas distribution pipe is provided below with air distribution holes;

[0059] The air distribution holes are arranged in rows along the axial direction of the gas distribution pipe and are spaced from each other, and at least one row of air distribution holes is arranged below each gas distribution pipe; more than one row of air distribution holes is arranged in the lower half of each gas distribution pipe along the axial direction, for sending the gas in the pipe to the material channel inside the box body of the shell body; the arrangement mode of the gas distribution pipe and the hole opening mode on the pipe wall can ensure that the gas is uniformly diffused to the entire cross section of the shell body and passes through the material layer upward; the cross-sectional shape of the gas distribution pipe can be circular, oval, rhombic, oblong or other shapes, and the shape of the air distribution hole is not circular, but can be a strip-shaped gap or the like;

[0060] Preferably, the gas distribution pipe is a straight pipe;

[0061] Preferably, 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 extension direction of the gas distribution pipe in the horizontal direction is perpendicular to the extension direction of the heat exchange pipe or the heat exchange plate in the horizontal direction; the perpendicular arrangement of the extension direction of the gas distribution pipe in the horizontal direction and the extension direction of the heat exchange pipe or the heat exchange plate in the horizontal direction is beneficial to more uniform distribution of the gas in the heat exchange pipe or the heat exchange plate area, and avoids local airflow shortage to cause poor material fluidization or local blockage;

[0062] Preferably, the opening rate of the first fluidization air gas distribution assembly and the second fluidization air gas distribution assembly is greater than the opening rate of the replacement air gas distribution assembly;

[0063] Preferably, the open area ratio of the air distribution holes of the uppermost first fluidizing air gas distribution assembly is greater than the open area ratio of other positions. The distribution of the gas distribution pipes of the first fluidizing air gas distribution assembly can be adjusted, such as near the feed inlet, that is, the gas distribution pipes of the corresponding pipe distribution region of the tip region of the material cone can be distributed more densely, and the air distribution holes are opened more, so that the material of the corresponding tip region is loosened (or flows) more violently under the condition of insufficient fluidization, and under the action of gravity, the material slides down from the high point, thereby eliminating the material cone and making the material layer region substantially horizontal.

[0064] Preferably, the drying heat exchanger assembly or the cooling heat exchanger assembly comprises a plurality of heat exchange pipes arranged in the horizontal direction, and the heat exchange pipes are serpentine pipes extending upward and downward.

[0065] Preferably, the two adjacent serpentine heat exchange pipes are arranged in an upper and lower staggered manner. The two adjacent serpentine heat exchange pipes are arranged in an upper and lower staggered manner, which increases the number of material splitting and converging in the internal flow channel of the heat exchanger assembly, increases the disturbance of the material side, and can increase the heat transfer coefficient of the material side; at the same time, the increase of the flow of the material also helps to reduce the slight bonding phenomenon of the material.

[0066] Preferably, the drying heat exchanger assembly is a tubular heat exchanger. The material above the first fluidizing air gas distribution assembly is in a fluidized state, which can better overcome the phenomenon that the material is easily deposited on the upper part of the heat exchange pipe. The disturbance of the heat exchange pipe to the material in the fluidized state is greater than that of the plate heat exchanger, thereby having better heat transfer effect.

[0067] Working principle and beneficial effects of the utility model:

[0068] By blowing gas or dry gas into the shell of the shell body through the first and second fluidizing air gas distribution assemblies, the material above the fluidizing air gas distribution pipe is in a fluidized state, and the characteristics of the gas-solid fluidization phenomenon are used to process the material raw material as follows:

[0069] a. Utilize the high turbulence and high backmixing characteristics of fluidization to eliminate the segregation phenomenon of the feed cone and the feeding process, and make the material uniformly distributed in the cross section of the shell body.

[0070] Theoretically, it is always desirable that the material moves downward in the tank of the gravity cooling section in a bulk flow manner, so that the material on the whole cross section experiences the same time of cooling process, thereby obtaining uniform and consistent cooling depth. However, the actual powder or granular material always has a certain particle size distribution range, when the material is freely spilled from the feed inlet to the stationary heat exchanger assembly or the upper part of the material, a conical material accumulation area, i.e. the feed cone, is formed. After the formation of the feed cone, the subsequent particles will appear the phenomenon that the large particle size material is enriched in the periphery of the cone, and the small particle size and powder material is enriched in the central part, i.e. the particle segregation phenomenon. The weight of the feed cone and the impact force of the feed form uneven pressure on the material below, causing the material in the central region of the feed cone to move downward at a fast speed, and the material around the feed cone to move downward at a slow speed, affecting the uniformity of the bulk flow of the material, thereby causing the cooling depth of the material in different tank cross section regions to be different. Since the material moving downward in the gravity cooling section in a bulk flow manner has the same cooling time, when the segregation phenomenon occurs, the phenomenon of uneven particle size distribution of the material on the cross section of the shell body tank will appear, and the cooling speed of the coarse particles is slower than that of the fine particles. This uneven cooling speed will cause the temperature of the material around the feed cone to be higher than that of the material in the central region, thereby exacerbating the cooling temperature difference.

[0071] The utility model discloses a shell body top is provided with material fluidization section (i.e. fluidization drying section and fluidization cooling section), under the condition of fluidization, the material layer is in high turbulence, high backmixing state, and the material has the characteristics similar to fluid, and the feed cone is automatically eliminated, forms the upper surface of horizontal fluidization bed layer, thereby make the uniform and consistent material pressure on the whole cross section of shell body, be favorable to the material in the gravity cooling section tank from top to bottom realize bulk flow, increase the uniformity of material cooling time in the cross section of shell body, further, under the condition of fluidization, the particle size distribution of material is uniform in the horizontal direction, and the segregation phenomenon of material does not exist, thereby guarantee that the material enters subsequent cooling process with uniform particle size distribution, eliminates the uneven cooling condition brought by the different particle size distribution of feed.

[0072] b. utilize the high heat transfer / mass transfer rate of fluidization drying to strengthen the drying process and improve the drying capacity per unit cross section area.

[0073] When the material is in fluidization, the heat transfer process between the material and the heat exchanger, the heat / mass transfer process between the gas and the material are significantly enhanced, thereby obtaining higher drying efficiency or lower final moisture requirement; the fluidized drying section has a much higher unit area heat transfer capacity than the gravity cooling section, i.e. the heat and mass transfer rates are significantly improved compared to the slowly moving material layer in the aerated state, which is very advantageous for the drying section superimposed on the gravity cooler (in this patent, the gravity cooling section), because the heat required for removing moisture by thermal drying is much greater than the heat required for cooling the material, and the fermentation product has a high requirement for 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 maximizing the drying capacity in the limited cross section, thereby increasing the moisture content of the feed, expanding the application range of the material, or reducing the requirement for the final moisture content of the pre-dried raw material; when hot dry gas is used, the moisture content in the gas can be further reduced, the mass transfer driving force is increased, and the dry gas can carry more moisture, thereby reducing the moisture content of the material at the end of drying. Fermentation products often have the characteristics of caking and scarring during the drying process, and the violent turbulence and back mixing between the materials in fluidization have good dispersion and breaking effect on the wet material, and the strong scouring of the shell and the heat exchanger wall surface also reduces or avoids the tendency of the material to scab on the wall surface.

[0074] c. Utilizing the high gas-solid contact efficiency of fluidization, the wet hot gas in the particle gap of the fluidized cooling section is efficiently replaced by dry gas, and the material is pre-cooled and moisture homogenized at the same time.

[0075] Powdered or granular materials have a certain porosity, and after drying treatment, the particle gap of the material is usually filled with wet hot gas, and the moisture can be water vapor, methanol vapor, etc. The relative humidity of the moisture in the gas is very low at high temperature, but it becomes larger after cooling, and it is more easily absorbed by the particles, thereby increasing the moisture in the particles, i.e. 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 surface of the heat exchanger, especially when the temperature of the wall surface of the heat exchanger and its vicinity is very low, the humid gas is more likely to condense, directly causing the material to caking or the wall surface of the heat exchanger to scab, therefore, for materials that are prone to moisture absorption, the humid hot gas must be replaced with dry gas, and the fluidization gas can play this role.

[0076] Further, in the fluidized state, the contact efficiency between the particles and the fluidization 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; the heat transfer efficiency is also very high, thereby fully utilizing the heat energy of the low-temperature fluidization gas to reduce the temperature of the feed, eliminating the temperature and moisture differences between particles with different moisture contents and different particle sizes, and achieving better cooling and moisture homogenization effect.

[0077] d. By setting the cooling section (including fluidized cooling section) multi-layer cooling heat exchanger and setting the multi-layer gas distribution assembly, the material and coolant temperature difference in each layer of the cooling section is controlled, and dry air with different flow and dryness is passed in, so that the material flow is promoted, the moisture absorption, caking and scarring problems of the material in the deep cooling process are avoided, the cooling efficiency and cooling uniformity of the cooling section are improved, and the caking hidden danger in the product transportation or storage link is reduced or avoided. In addition, when the corresponding material layer is in a fluidized bed, the effect of eliminating the feed cone and material segregation of the gas distribution assembly is basically independent of the size and shape of the cross section of the bed, so a larger cross-sectional area can be used, a larger heat exchanger assembly or a multi-layer heat exchanger assembly with different combination modes can be put in, and the influence of non-integral flow and uneven particle size distribution on the cooling uniformity caused by the increase of the height of the feed cone can be avoided, so that a smaller height-diameter ratio (for a rectangular shell, it can be described as a height-width ratio or a height-length ratio, or as a height-cross-sectional area ratio) can be used to obtain a larger material processing capacity, or in the case of the same amount of feed or the same temperature difference of the material cooling, a lower equipment height is used, which corresponds to the reduction of the height of the plant or the secondary lifting height of the material, thereby increasing the investment or energy consumption. BRIEF DESCRIPTION OF DRAWINGS

[0078] Figure 1 It is a structure schematic view of the drying and cooling integrated machine of the embodiment 1 of the utility model;

[0079] Figure 2 It is a structure schematic view of the drying and cooling integrated machine of the embodiment 2 of the utility model;

[0080] Figure 3 It is a structure schematic view of the drying and cooling integrated machine of the embodiment 3 of the utility model;

[0081] Figure 4 It is a position relation schematic view of the gas distribution assembly and the heat exchanger assembly;

[0082] Figure 5 It is a structure schematic view of the gas distribution assembly in the longitudinal cross-sectional direction;

[0083] Figure 6 It is a structure schematic view of the gas distribution assembly in the transverse cross-sectional direction;

[0084] Figure 7 It is a structure schematic view of the air distribution hole of the embodiment of the utility model

[0085] Figure 8 It is a structure schematic view of the staggered arrangement of the upper and lower adjacent tubular heat exchangers;

[0086] Figure 9Structure schematic view of staggered arrangement of upper and lower adjacent plate heat exchangers;

[0087] Figure 10 Structure schematic view of tube heat exchanger;

[0088] Figure 11 Structure schematic view of plate heat exchanger;

[0089] Figure 12 Structure schematic view of gas exchange hole provided on heat exchange plate;

[0090] 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 pipe, 33 is a heat exchange plate, 4 is a first fluidization air gas distribution assembly, 5 is a second fluidization air gas distribution assembly, 6 is a replacement air gas distribution assembly;

[0091] 1000 is a first material channel, 2000 is a wind distribution unit, 3000 is a second material channel;

[0092] 101 is a feeding port, 102 is an exhaust port, 103 is a discharging port, 104 is a material layer upper surface, 105 is a feeding material flow, 106 is a discharging material flow, 107 is an expansion section;

[0093] 100 is a fluidization drying section, 200 is a fluidization cooling section, 300 is a gravity cooling section;

[0094] 7 is an auxiliary material bin, 8 is a material level meter, 9 is a discharger, 10 is an auxiliary discharging device, 11 is a gas distribution pipe, 111 is a wind distribution hole;

[0095] 400 is an inlet distribution main pipe, 500 is an outlet distribution main pipe, 600 is a first connecting pipe;

[0096] 700 is a gas distribution main pipe, 800 is a second connecting pipe. DETAILED DESCRIPTION

[0097] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings.

[0098] In the utility model, the definition of net cross section is as follows: on any horizontal cross section of the box body of the fluidization drying section, the fluidization cooling section and the gravity cooling section, the material channel cross section area after deducting the cross section area occupied by the heat exchanger assembly.

[0099] The definition of fluidization number is as follows: the ratio of the operating air speed to the critical fluidization speed calculated according to the average particle diameter of the material; wherein the operating air speed is the average air speed calculated according to the net cross section of the box body, and the operating air speed is generally indicated by the fluidization air speed in the material fluidization section.

[0100] The calculation method of critical fluidization velocity: according to the calculation formula given in the book "Fluidization Drying Process and Equipment" published by Science Press in 1996, Tong Jingshan, page 166.

[0101] Example 1

[0102] As Figure 1 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, a gas supply system and a heat exchange medium supply system (not shown in the figure).

[0103] The drying heat exchanger assembly 2 and the cooling heat exchanger assembly 3 are plate heat exchangers or tube heat exchangers, and the heat exchange tubes in the tube heat exchanger are arranged at intervals, and the heat exchange plates in the plate heat exchanger are arranged at intervals. Figure 4 and Figure 5 As shown, the heat exchange plates 33 of the drying heat exchanger assembly 2 and the cooling heat exchanger assembly 3 are provided with first material passages 1000 that penetrate up and down, that is, the gaps between the heat exchange tubes in the tube heat exchanger and the gaps between the heat exchange plates in the plate heat exchanger are the first material passages 1000.

[0104] As Figure 4 shown, the gas distribution assembly is horizontally arranged in the shell body 1 and includes air distribution units 2000 arranged at intervals along the cross section of the shell body 1 and second material passages 3000 located between the air distribution units 2000, the second material passages 3000 being channels that penetrate up and down.

[0105] As Figure 4 , Figure 5 and Figure 6 shown, the air distribution unit 2000 includes a gas distribution pipe 11, and a plurality of gas distribution pipes 11 are arranged at intervals on the same horizontal plane and uniformly arranged in parallel with each other. Figure 5 and Figure 6 As shown, the gas distribution pipe 11 is provided with air distribution holes 111 below. The gas distribution pipe 11 is a straight pipe, and the air distribution holes 111 are arranged in rows at intervals along the length direction of the gas distribution pipe 11. Figure 7 As shown in (a), a row of air distribution holes 111 is arranged below the gas distribution pipe 11. Figure 7 As shown in (b), three rows of air distribution holes 111 are arranged below the gas distribution pipe 11 to increase the flow.

[0106] As Figure 4 , Figure 5 and Figure 6As shown, the horizontal extension direction of the gas distribution pipe 11 is perpendicular to the horizontal extension direction of the heat exchanger pipe 32 in the drying heat exchanger assembly 2 or the cooling heat exchanger assembly 3 (e.g., Figure 4 (as shown in (a)), or the horizontal extension direction of the gas distribution pipe 11 is perpendicular to the horizontal extension direction of the heat exchange plate 33 in the drying heat exchanger assembly 2 or the cooling heat exchanger assembly 3 (as shown in (a)). Figure 4 (b) shows that the first material channel 1000 and the second material channel 3000 are perpendicularly connected to each other. The arrangement of the gas distribution pipe 11 and the opening on the pipe wall are used to ensure that the gas diffuses evenly across the entire cross-section of the shell body 1 and passes upward through the material layer; the shell body 1 is equipped with a gas distribution main pipe 700 on the outside of the shell, and a second connecting pipe 800 connecting the gas distribution pipe 11 to the main pipe.

[0107] like Figure 1 As shown, the shell body 1 is a vertical shell, which usually has a rectangular cross-section. The top of the shell body 1 is provided with a feed inlet 101 and a vent 102, and the bottom of the shell body 1 is provided with a discharge outlet 103.

[0108] 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 discharge section from top to bottom. The upper half of the fluidized drying section is also the feeding section. The feeding section is typically a shell with a rectangular cross-section that is consistent from top to bottom. The top of the feeding section shell is provided with one or more feed ports 101 for adding the powdery or granular material to be processed, such as... Figure 1 As shown, a feed flow 105 is formed; the top of the feed section shell is provided with one or more exhaust ports 102 for venting gas; the internal space of the feed section shell is used to accommodate material, which typically fills part of the shell during operation, and under fluidization, has a distinct upper surface 104 of the material layer, with a certain height of space above the material, where small particles entrained in the exhaust gas re-sink to the material layer under gravity; the bottom of the feed section shell is open, usually equal to the cross-section of the feed section shell, for connecting to 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 remaining space above the upper surface of the material layer in the fluidized drying section 100. A level gauge is installed on the feed section shell to measure the material level and transmit it electrically to the control system.

[0109] In this embodiment, as 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.

[0110] The fluidized drying section 100 is equipped with a drying heat exchanger assembly 2 connected to the heat exchange medium supply system.

[0111] The fluidized cooling section 200 and the gravity cooling section 300 are equipped with cooling heat exchanger assemblies 3 connected to the heat exchange medium supply system.

[0112] The heat exchange medium supply system is used to supply heat medium and cold medium to the drying heat exchanger assembly 2 and the cooling heat exchanger assembly 3, respectively.

[0113] In this embodiment, the drying heat exchanger assembly 2 is preferably a tubular heat exchanger because heat exchange tubes have better pressure and temperature resistance than heat exchange plates, and can better adapt to high-temperature and high-pressure heat sources such as superheated steam. Furthermore, the material above the first fluidizing air distribution assembly is in a good fluidized state, which better overcomes the phenomenon of material deposition at the top of the heat exchange tubes. The heat exchange tubes cause greater disturbance to the material in the fluidized state compared to plate heat exchangers, thus resulting in better heat transfer. In the gravity cooling section 300, a plate heat exchanger is preferred. When the material is in a downward, slowly moving, aerated overall flow state, the flow channels between the heat exchange plates 33 are more conducive to material and gas flow, avoiding local flow blockage. In the fluidized cooling section, either type of heat exchanger can be used. When a tubular heat exchanger is used, a higher fluidization velocity should be employed to reduce the possibility of local flow blockage. Figure 10 As shown, the tubular heat exchanger includes multiple heat exchange tubes 32 arranged at intervals. The heat exchange tubes are serpentine tubes extending vertically, and two adjacent serpentine heat exchange tubes are arranged in a staggered manner.

[0114] The external space of the drying heat exchanger assembly 2 and the cooling heat exchanger assembly 3 is a material channel, while the internal space is a heat exchange medium channel. The two are separated by the wall of the drying heat exchanger assembly 2, and the heat is transferred through the wall.

[0115] like Figure 11 As shown, the plate heat exchanger is equipped with rows of dot-welded areas and staggered linear welds. The dot-welded areas form pillow-shaped expansion zones that serve as channels for the heat exchange medium. The area around each local welded area bulges out, forming a roughly bowl-shaped depression. The staggered linear welds create a serpentine path for the heat exchange medium. The depressions in adjacent rows (or columns) are typically staggered to increase the disturbance to the internal fluid flow and the flow of external granular materials. The overall serpentine flow pattern avoids internal fluid short-circuiting, increases the flow path length, and improves the flow velocity. These measures significantly improve the flow and heat transfer characteristics of the fluid and materials.

[0116] like Figure 12As shown, when the drying heat exchanger assembly 2 and the cooling heat exchanger assembly 3 are plate heat exchangers, in order to improve the flow of the gas inside the drying heat exchanger assembly 2 and the cooling heat exchanger assembly 3, a gas exchange hole can be provided on the heat exchange plate 33 of the plate heat exchanger. The diameter of the gas exchange hole is generally 10-20 mm, for the gas to pass through, increasing the gas flow between different heat exchange plates, to stabilize the gas flow state.

[0117] As shown in Figure 10 , Figure 11 , the housing body 1 is provided with an inlet distribution header 400 and an outlet distribution header 500 of the heat exchange medium on the outside of the housing, 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 header together. 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 header 400, and after indirect heat exchange with the material in the heat exchanger assembly, it is collected into the outlet distribution header 500. The heat exchange medium can enter the heat exchanger assembly from the lower distribution header and be discharged from the upper distribution header, i.e. the inlet distribution header 400 is arranged below the outlet distribution header 500, so as to form a countercurrent heat exchange opposite to the flow direction of the material, to obtain a higher heat exchange temperature difference and faster heating or cooling of the material. 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 lower, so that the heating process or the cooling process of the material is carried out gently.

[0118] When the drying heat exchanger assembly 2 uses a steam heat source, the inlet distribution header 400 of the heat source is located at the upper part of the drying heat exchanger assembly 2, and the outlet distribution header 500 is located at the lower part of the drying heat exchanger assembly 2; when hot water or heat conducting oil heat source is used, the arrangement is reversed, and at this time, the heat source and the material form a countercurrent heat exchange process.

[0119] As shown in Figure 1 , the gas distribution assembly includes a first fluidized air gas distribution assembly 4 and a second fluidized air gas distribution assembly 5 arranged in the fluidized drying section 100 and the fluidized cooling section 200 respectively, and the first fluidized air gas distribution assembly 4 and the second fluidized air gas distribution assembly 5 are connected with the gas supply system respectively. Figure 1 As shown in , the first fluidized air gas distribution assembly 4 is arranged below the drying heat exchanger assembly 2. The fluidized cooling section 200 is provided with a layer of cooling heat exchanger assembly 3, and the second fluidized air gas distribution assembly 5 is arranged below the cooling heat exchanger assembly 3.

[0120] As shown in Figure 6 , the first fluidized air gas distribution assembly 4 and the second fluidized air gas distribution assembly 5 include a plurality of gas distribution pipes 11 arranged in the housing body 1.

[0121] The cross-sectional shape of the gas distribution pipe 11 can be circular, oval, rhombic or other shapes, and the shape of the openings can also be other than circular, such as a strip-shaped gap, and the number of rows of openings and the arrangement are not specified.

[0122] The first fluidization air distribution assembly 4 is used to introduce hot dry gas or hot gas without initial equipment dehumidification into the housing body 1, and the air flow is combined with the air flow of the second fluidization air distribution assembly 5, so that the material in the fluidized drying section 100 is in a fluidized state. The high turbulence and high backmixing characteristics of the material in the fluidized state eliminate the feed cone and the feed segregation phenomenon, so that the material entering the fluidized drying section 100 spreads horizontally and the particle size of the material is uniformly distributed into the fluidized cooling section 200. The high heat transfer / mass transfer rate in the fluidized state can achieve higher drying efficiency or lower final moisture requirement. 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, and more moisture can be carried, thereby reducing the moisture content of the material at the end of drying. The high turbulence and high backmixing characteristics of the material in the fluidized state have good dispersion and deagglomeration effects on the wet material, and the strong scouring of the housing and the heat exchanger wall also reduces or avoids the tendency of the material to form a scab on the wall surface.

[0123] The second fluidization air distribution assembly 5 is used to introduce dry gas into the housing body 1, so that the material in the fluidized cooling section 200 is in a fluidized state. The high gas-solid contact efficiency of the fluidized state enables the dry gas to efficiently displace the wet hot gas in the particle gap of the material in the fluidized cooling section, while pre-cooling and homogenizing the moisture of the material, and ensuring that the material in the fluidized cooling section 200 is uniformly distributed in particle size and that the moisture in the gap between the materials is fully displaced and discharged into the gravity cooling section 300. Preferably, dry cold gas is introduced through the second fluidization air distribution assembly 5 to further cool the material using the heat energy of the low-temperature gas.

[0124] To achieve the above-mentioned purposes, in the present embodiment, the gas supply system includes a gas dehumidification device, a gas heating device and a gas cooling device, and the heat transfer medium supply system includes a fluid pressure / flow control device or a fluid heating device and a fluid cooling device.

[0125] The gas dehumidification device is used to remove moisture from the gas to obtain dry gas, and the gas cooling device is used to control the temperature of the dry gas entering the fluidized cooling section 200 and the gravity cooling section 300.

[0126] The gas heating device is used to heat the dry gas entering the fluidized drying section 100 or the gas without dehumidification by the gas dehumidification device.

[0127] The fluid pressure / flow control device is used to control the pressure or flow of the heat medium or the cooling medium.

[0128] The fluid heating device is used for heating the liquid heat medium.

[0129] The fluid cooling device is used for controlling the temperature of the cooling medium to avoid material moisture absorption, caking or scabbing on the wall of the heat exchanger.

[0130] In the embodiment, the cross-sectional areas of the upper and lower shells of the fluidized drying section 100 and the fluidized cooling section 200 are uniform, the fluidized air speeds of the first fluidized air gas distribution assembly 4 and the second fluidized air gas distribution assembly 5 are average air speeds calculated by using the horizontal net cross-sectional areas of the fluidized drying section 100 and the fluidized cooling section 200, when the first fluidized air gas distribution assembly 4 and the second fluidized air gas distribution assembly 5 work simultaneously, the fluidized air speed generated by the ventilation volume of the second fluidized air gas distribution assembly 5 is not less than 1 times the critical fluidized speed calculated according to the average particle size of the material, the fluidized air speed generated by the sum of the ventilation volumes of the first fluidized air gas distribution assembly 4 and the second fluidized air gas distribution assembly 5 is not less than 1.5 times the critical fluidized speed calculated according to the average particle size of the material, and the fluidized air speed generated by the sum of the ventilation volumes of the first fluidized air gas distribution assembly 4 and the second fluidized air gas distribution assembly 5 is not more than 15 times the critical fluidized speed calculated according to the average particle size of the material.

[0131] The fluidized cooling section 200 and the gravity cooling section 300 are provided with two or more layers of cooling heat exchanger assemblies 3 from top to bottom, each layer of cooling heat exchanger assemblies 3 forms a cooling section, and the temperatures of the cooling medium of each layer of cooling heat exchanger assemblies 3 decrease from top to bottom, as shown in Figure 1 In the embodiment, three layers of cooling sections are provided.

[0132] Each layer of drying heat exchanger assemblies 2 and cooling heat exchanger assemblies 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 connected heat exchanger assembly.

[0133] As shown in Figure 1 The gas distribution assembly further includes a displacement air gas distribution assembly 6 provided in the gravity cooling section 300 and connected with the gas supply system, and the structure form and arrangement of the gas distribution pipe 11 of the displacement air gas distribution assembly 6 are the same as those of the first fluidized air gas distribution assembly 4 and the second fluidized air gas distribution assembly 5.

[0134] The displacement air gas distribution assembly 6 is used for introducing dry gas into the shell body 1.

[0135] As shown in Figure 1 Each layer of cooling heat exchanger assemblies 3 in the gravity cooling section 300 is provided with a layer of displacement air gas distribution assembly 6 below.

[0136] In the embodiment, the cross-sectional area of the gravity cooling section 300 is uniform, the operating air speed of the displacement air distribution assembly 6 is the average air speed calculated according to the horizontal net cross-sectional area of the gravity cooling section 300, and the operating air speed generated by the ventilation volume or the sum of the ventilation volumes of the displacement air distribution assembly 6 is 0-0.5 times the critical fluidization speed calculated according to the average particle size of the material.

[0137] When the first fluidization air distribution assembly 4, the second fluidization air distribution assembly 5, and the displacement air distribution assembly 6 work simultaneously, the operating air speed generated by the ventilation volume of the second fluidization air distribution assembly 5 calculated independently is not less than 0.7 times the critical fluidization speed calculated according to the average particle size of the material, the fluidization air speed generated by the sum of the ventilation volumes of the second fluidization air distribution assembly 5 and the displacement air distribution assembly 6 calculated independently is not less than 1.2 times the critical fluidization speed calculated according to the average particle size of the material, and the fluidization air speed generated by the sum of the ventilation volumes of the first fluidization air distribution assembly 4, the second fluidization air distribution assembly 5, and all displacement air distribution assemblies 6 is not higher than 15 times the critical fluidization speed calculated according to the average particle size of the material.

[0138] As shown in Figure 1 The drying and cooling all-in-one machine further comprises an auxiliary bin 7, the inlet of the auxiliary bin 7 is connected with the discharge port 103, and the outlet of the auxiliary bin 7 is connected with the feeding port 101.

[0139] As shown in Figure 1 The drying and cooling all-in-one machine further comprises a material level meter 8 and an adjustable flow discharge device 9.

[0140] The material level meter 8 is arranged at the top of the shell body 1 and is used to measure the material level height of the material in the shell body 1.

[0141] The discharge device 9 is connected with the discharge port 103 and is used to adjust the discharge speed of the material and control the size of the discharge flow 106 so as to control the material level height of the material in the shell body 1. In the embodiment, the pneumatic conveying equipment is used for feeding, that is, the outlet of the discharge device 9 is connected with the pneumatic conveying equipment, the air inlet of the pneumatic conveying equipment uses the same parameters as the displacement air inlet of the gravity cooling section, and the pneumatic conveying equipment is provided with a return bypass for feeding the auxiliary bin 7.

[0142] The discharger 9 can be any one of rotary lock gas discharge valve, vibration discharger, belt discharger, single shaft or multi-shaft screw discharger and the like. The discharger 9 has a driving device and a discharging speed controller which controls the discharging speed of the discharger 9 by receiving the electric signal of the level meter 8 installed on the top of the shell body 1, so as to ensure that the upper surface of the material layer is higher than the upper surface of the first fluidized air distribution assembly 4 of the fluidized drying section 100 by a certain height, thereby forming a fluidized material layer with a certain height on the upper portion, ensuring the uniformity of the material and realizing the drying or deep drying of the sent material to be dried.

[0143] The discharging section is an upper large and lower small discharging cone for receiving the powder or granular material from the gravity cooling section 300. The upper portion of the cone has the same cross section as the gravity cooling section 300 and is connected together. The cone gradually reduces from top to bottom and transitions to the same cross section as the discharging port 103 and is connected together.

[0144] As shown in Figure 1 The wall surface of the discharging section can be provided with one or more auxiliary discharging devices 10 such as vibration, knocking and the like. The auxiliary discharging devices 10 can be mechanical vibration or knocking to assist the flow of the material in the cone. Or one or more auxiliary discharging devices for compressed gas impact are installed to release compressed air to loosen the material. The auxiliary discharging device 10 prevents the local hardening or "arch bridge" of the material and ensures the smooth discharge of the material in the form of overall flow.

[0145] The drying and cooling all-in-one machine further includes supports, lifting lugs, flanges, manholes, handholes, sight glasses, instrument mounting seats (holes) and the like for supporting, fixing, lifting, connecting, repairing, observing, detecting and the like. These are required in conventional engineering or equipment design and will not be described here.

[0146] The discharging speed of the material is controlled by the discharger 9 to ensure that the upper surface of the material layer is higher than the uppermost drying heat exchanger assembly 2 by a certain height, thereby ensuring that the heat exchanger assembly is completely buried in the material.

[0147] The upper surface 104 of the fluidized material layer is located above the drying heat exchanger assembly 2 (for example: 0-200mm), which ensures that the heat exchanger is in full filling state with the material and exchanges heat with the material, and reduces the energy consumption required to overcome the resistance of the material layer.

[0148] The method for drying and cooling the material by the drying and cooling all-in-one machine of the embodiment includes the following steps:

[0149] S1, the dry and cooled material is used to bury the dry heat exchanger assembly 2 and the cooling heat exchanger assembly 3 in the shell body 1, and the preset height above the dry heat exchanger assembly 2 is reached.

[0150] S2, the first fluidization air distribution assembly 4 is used to pass hot dry gas or hot gas without dehumidification into the shell body 1, and the second fluidization air distribution assembly 5 is used to pass dry gas or dry cold gas into the shell body 1, so that the material above the first fluidization air distribution assembly 4 and the second fluidization air distribution assembly 5 is in a fluidized state, and the material is uniformly distributed in the cross section of the shell body 1 and enters the gravity cooling section 300 in this uniformly distributed state.

[0151] S3, the dry heat exchanger assembly 2 of the fluidized drying section 100 is used to heat and dry the material, and the hot dry gas is used to heat and dry the material under fluidization, the humid gas between the material particles is fully replaced, and the moisture in the material and the humid gas is taken out of the shell body 1.

[0152] Alternatively, the hot gas without dehumidification is used to heat and dry the material under fluidization, and the moisture in the material is taken out of the shell body 1.

[0153] 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.

[0154] At the same time, the dry gas is passed into the fluidized cooling section 200 by the second fluidization air distribution assembly 5, so that the material is fluidized, the humid gas between the material particles is fully replaced by the dry gas, and the moisture in the humid gas and the material is taken out of the shell body 1.

[0155] 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, caking or scarring on the heat exchanger wall.

[0156] In step S1, the method for burying the dry heat exchanger assembly 2 and the cooling heat exchanger assembly 3 in the shell body 1 by using the material is as follows:

[0157] S11, the first fluidization air distribution assembly 4 and the second fluidization air distribution assembly 5 are arranged at the upper end inside the shell body 1, and before drying and cooling the material, the dry and cooled material is quickly added to the preset height in the shell body 1 by means of continuous transfer of the auxiliary material bin 7, manual feeding or other drying and cooling systems.

[0158] S12, when the material level rises to the second fluidization air distribution assembly 5 of the fluidized cooling section 200, the second fluidization air distribution assembly 5 is started to pass in the gas so that the material above the gas distribution assembly is in a fluidized state.

[0159] S13, when the material level rises to the first fluidization air distribution assembly 4, the corresponding first fluidization air distribution assembly 4 is started to pass in the gas until the material layer reaches the normal production level, and during the whole process, the material above the second fluidization air distribution assembly 5 is in a fluidized state.

[0160] The above operation is sequentially performed upwards until the material level reaches the preset height, and finally the fluidized drying section 100, the fluidized cooling section 200 and the gravity cooling section 300 are arranged upwards.

[0161] According to the needs, the gas passed in by the second fluidization air distribution assembly 5 can be dry gas or dry and cold gas, and the gas passed in by the first fluidization air distribution assembly 4 can be dry gas or hot gas without dehumidification.

[0162] S14, then, 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.

[0163] The drying and cooling method further comprises the step S5:

[0164] On the basis of the first fluidization air distribution assembly 4 and the second fluidization air distribution assembly 5 arranged in the fluidized drying section 100 and the fluidized cooling section 200 respectively, a plurality of displacement air distribution assemblies 6 are arranged in the gravity cooling section 300 from top to bottom.

[0165] Meanwhile, a small amount of dry gas or dry and cold gas is passed into the gravity cooling section 300 by the displacement air distribution assembly 6, a small amount of moisture in the gas between the material particles is taken out of the shell body 1, and the material is kept in a dry and cold gas environment.

[0166] When the powder and particle products are processed, especially when the products produced by the fermentation plant are easy to absorb moisture and form lumps, the utility model has the following beneficial effects:

[0167] 1. The strong dispersion and crushing effect of the fluidization turbulence and back mixing on the wet material, and the strong scouring effect on the shell and heat exchanger wall, effectively solve the problems of moisture absorption, lumping, and scarring on the surface of the heat exchange plate (or tube) during the drying or cooling process, especially the first layer and the second layer of the heat exchanger assembly in contact with the material, thereby ensuring long-term stable operation of the equipment without blockage, scarring, and constant heat exchange efficiency, and no lumps in the material itself during the cooling process.

[0168] 2. The high heat / mass transfer rate of fluidization drying strengthens the drying process, improves the drying / cooling capacity per unit cross-sectional area, thereby improves the unit area production capacity, or improves the feed moisture, and expands the application range of the material.

[0169] 3. The high turbulence and high backmixing characteristics of fluidization eliminate the segregation phenomenon of the feed cone and the feeding process, and the material is uniformly distributed in the cross section of the shell body. The entire gravity cooling process is uniform, the cooling temperature is further reduced, and a product with lower temperature, more uniform temperature and moisture, and no moisture absorption can be obtained, thereby effectively solving the product hardening phenomenon during the product storage and transportation period.

[0170] 4. The functions of drying or deep drying, moisture uniformity and deep cooling of the material are completed in the same equipment, which expands the performance of the equipment.

[0171] 5. The height-diameter ratio of the equipment is reduced, and the drying or deep drying function can still be realized under a lower height-diameter ratio, while ensuring uniform and consistent deep cooling effect, or a larger cross section can be used under the same height and ensure the drying / cooling effect, thereby improving the production capacity of the equipment. The reduction of the equipment height also reduces the equipment and plant investment.

[0172] In this embodiment, the implementation effect of the drying and cooling 70% lysine fluidized bed granulation product is given. The feed is hot material with qualified particle size discharged from the granulation fluidized bed system and screened, and the drying and cooling all-in-one machine of the present application is used instead of the original fluidized bed drying / cooling machine to perform deep drying and deep cooling operation on the material, thereby obtaining the final product with qualified particle size, moisture and temperature. The incoming material flow is 6.5 t / h, the particle size range of the incoming material is 0.6-1.7 mm, the average particle size is 1.1 mm, the initial moisture is 2.5-3%, the temperature is 75-85℃, the required product moisture is ~2%, and the temperature is 25-30℃. The critical fluidization speed calculated according to the average particle size of the particles is ~0.21 m / s (changes with air temperature and pressure parameters). The drying / cooling structure, process parameters and effects are as follows:

[0173] 1. The entire box can be divided into four sections according to the different environments of the materials, which are fluidized drying section, fluidized cooling section, gravity cooling section and discharge section. The fluidized drying section is the deep drying section of the material, and the fluidized cooling section is the high temperature cooling section of the material, which is internally 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 divided into two layers, which are medium temperature cooling section and low temperature cooling section, which are internally provided with a layer of cooling heat exchanger assembly 3, a layer of displacement wind gas distribution assembly 6, a layer of cooling heat exchanger assembly 3 and a layer of displacement wind gas distribution assembly 6 from top to bottom; the discharge section is a inverted conical discharge hopper, and the discharge port 103 at the lower part is connected with the discharger 9. The rest is omitted.

[0174] 2. All the fluidized wind or displacement wind provided by the gas distribution assembly is dry wind after the environmental air is dehumidified by the gas dehumidification equipment, and the dew point temperature is 0~5℃; part of the gas is heated to become 100~150℃ hot dry wind after passing through the gas heating equipment, and is sent into the fluidized drying section 100 through the first fluidized wind gas distribution assembly 4; the rest of the gas is cooled to become 20~25℃ cold dry wind after passing through the gas cooling equipment, and then is sent into the fluidized cooling section 200 (high temperature cooling section) through the second fluidized wind gas distribution assembly 5, or is sent into the gravity cooling section 300 (medium temperature cooling section and low temperature cooling section) through the displacement wind gas distribution assembly 6 at the same time.

[0175] 3. The deep drying section adopts steam and hot air combined heating. The drying heat exchanger assembly 2 adopts tubular heat exchanger, and the serpentine heat exchange pipe 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 the heat exchange coefficient can reach 100~150w / m 2The main heat required for drying is provided by the heat exchanger, the inlet distribution header is on the top and the outlet distribution header is on the bottom, and the heat exchanger operates in parallel with the material flow. The hot dry air at 70-75℃ after heat exchange with the material from the fluidized cooling section 200 and the gravity cooling section 300 is combined with the hot dry air at 100-150℃ introduced through the first fluidized air distribution assembly 4, and then used to fluidize the material layer, provide part of the heat, and carry away the steam generated during the drying process. The corresponding operating air speed of the air volume of the first fluidized air distribution assembly 4 calculated alone is generally not less than 0.1 m / s, and the corresponding fluidization number is not less than 0.5. The corresponding operating air speed of the sum of the air volume of all dry air coming from the lower part is generally not less than 0.4 m / s, and the corresponding fluidization number is not less than 2, so that the material layer is in good fluidization, and the feed cone and feed segregation phenomenon can be well eliminated. In order to improve the heating capacity of the hot air, without generating excessive entrainment, the operating air speed calculated alone according to the air volume of the first fluidized air distribution assembly 4 can be increased to 0.8 m / s, and the corresponding fluidization number can reach 3.8. The operating air speed after the air from the lower part is combined can reach more than 1.1 m / s, and the corresponding fluidization number can reach 5.2. Since the incoming material is screened material with less fine particles, the entrainment amount is not large at this fluidization speed, and it is also beneficial to further carry out the fine powder in the product and improve the product quality.

[0176] 2. The cooling heat exchanger assembly 3 of the three-layer cooling section adopts a plate heat exchanger, the coolant is water, the inlet distribution header is on the bottom, the outlet distribution header is on the top, and the heat exchanger 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 fluidized air (plus a small amount of displacement air when the displacement air is turned on). The cooling water inlet temperature of the cooling heat exchanger assembly 3 is controlled at 30-35℃, which reduces the heat transfer temperature difference between the material and the coolant, and also avoids excessive air relative humidity, which can cause material to form scabs on the cooling heat exchanger assembly 3 wall or particles to absorb moisture or form hardening due to surface condensation. In the bed layer of the fluidized cooling section 200, when all the displacement air assemblies are in the closed state, the required fluidization air volume is entirely from the second fluidized air distribution assembly 5, and the generated fluidization air speed is 0.32-0.6 m / s, and the fluidization number is between 1.5 and 2.9. When the displacement air assembly is turned on, the total air volume of the fluidized air and the displacement air remains unchanged, i.e. the fluidization number generated by the total air volume is still between 1.5 and 2.9. At this time, the lower limit of the fluidization air speed calculated according to the air volume of the second fluidized air distribution assembly 5 is reduced to 0.21 m / s, and the corresponding fluidization number is about 1, so that the material is uniformly and fully operated in a bubbling fluidization state under two working conditions, the water vapor contained in the air in the material gap is carried out, and the local material flow blockage is avoided. 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 material in the fluidization to the heat exchange wall also prevents or reduces the wall scabbing.

[0177] The cooling water of the cooling heat exchanger assembly 3 of the medium-temperature cooling section is controlled at 22-25°C, so that a more ideal cooling effect is obtained while avoiding scabbing; at the same time, replacement air is introduced, and the operating air speed is 0.05-0.1 m / s, so that the material is in a fluidization number of 0.24-0.48, the water vapor in the material gap is taken out to maintain a dry air environment, and at the same time, the material is in an aerated state to improve the flowability of the material. Because the flowability of 70% lysine particles is good, and the moisture in the material has been fully replaced in the high-temperature cooling section, replacement air can also be not introduced in dry seasons to save air volume.

[0178] The cooling water of the cooling heat exchanger assembly 3 of the low-temperature cooling section is controlled at 8-20°C, so that a deep cooling effect of 25-30°C or below can be obtained. At this time, the material has been cooled to near the discharge temperature, the heat transfer temperature difference between the material and the coolant is low, the material is in a fully dry and cold environment, and there is basically no material moisture or condensation. Replacement air is generally not needed. Replacement air can also be opened according to the material and weather conditions, etc. If replacement air is introduced, a similar or lower operating air speed to that of the medium-temperature cooling section is used, but the operating air speed generated by the sum of the air volumes of the two replacement air assemblies should not exceed 0.5.

[0179] The effects are as follows:

[0180] (1) In actual application, in the hot and humid weather period in summer and autumn, the drying / cooling all-in-one machine of the embodiment can reduce the average moisture 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%. The moisture reduction of particles larger than the average particle size is about 0.5-1.0%, and the moisture reduction of particles smaller than the average particle size is about 0.2-0.5%, so the material is also homogenized. While reducing the moisture, the material temperature is cooled to ~25°C, which is lower than the average temperature in the hottest month of summer, and the temperature difference of the cooled material is very small. The system can be continuously operated for more than 60 days without material caking and scabbing on the heat exchanger; the cooling effect is stable and continuous.

[0181] The above deep drying and deep cooling effects, combined with strict control measures for moisture absorption in the downstream conveying and packaging process, basically eliminate the caking phenomenon of 70% lysine granular packaging products during long-term storage in summer and autumn.

[0182] (2) Product quality improvement. In the fluidized drying and fluidized cooling (high temperature cooling) process, the small amount of fine powder in the material can be further air- selected out; In the medium and low temperature cooling process, the material particles flow slowly and controllably, effectively preventing the product from being abraded and broken, and almost no fine powder is generated during cooling; In the medium and low temperature cooling process, the material is cooled mainly by indirect heat transfer, and the material is basically not in contact with the environment air, avoiding the increase of the water content of the product during the cooling process; The dry air with deep dehumidification can even make the water distribution of the material more uniform and further reduce the water content.

[0183] (3) The exhaust emission during the drying process and the cooling process is less than 3000m 3 / h, compared with the exhaust emission of 25000m 3 / h of the fluidized bed deep drying / cooling process, which is reduced by more than 85%, and the emission is significantly reduced; The exhaust gas is collected into the granulation bed to discharge a large amount of exhaust gas for dust and odor removal treatment, without additional setting.

[0184] (4) High energy utilization efficiency. Since indirect heat transfer with cooling water is used, the dehumidification and cooling link of air cooling is saved, and the ice water consumption in summer is reduced from 120m 3 / h to 35m 3 / h, saving about 70%.

[0185] Using the gravity flow of the material itself, a large number of pressurized and negative pressure suction links of the fluidized air and equipment operation links are saved, and the installed power of the whole system is reduced from 125kw to 30kw, saving about 75% of power consumption.

[0186] (5) The fluidized bed drying / cooling machine and its attached bag dust collector, drum induced fan and other auxiliary equipment occupy an area of 200m 2 above, and the drying and cooling all-in-one machine saves large equipment such as bag dust collector and drum induced fan and has less auxiliary equipment, and the area is only 60m 2 , saving 70%, thus saving equipment and plant investment.

[0187] Example 2

[0188] As Figure 2 shown, different from example 1, an enlarged section 107 is arranged above the shell body 1, specifically, the lower shell of the feeding section is a shell with a rectangular cross section, the upper shell is an enlarged shell with a rectangular cross section, and the shell between the upper and lower shells is a conical shell that gradually expands. A layer of first fluidized air distribution assembly 4 is arranged on both sides of the drying heat exchanger assembly 2.

[0189] In the present embodiment, two layers of first fluidizing wind gas distribution assembly 4 can be utilized to dry the incoming material, thereby increasing the moisture content of the feed, expanding the scope of the material, or reducing the final moisture content requirement of the pre-drying of the raw material, and further improving the quality of the product. The following is an illustration:

[0190] By passing a large amount of hot gas or hot dry gas into the upward first fluidizing wind gas distribution assembly 4, the flow rate of the gas plus the total amount of gas from the lower part corresponds to the fluidizing wind speed, which can even reach between 5 and 15, so that the material layer in the feed bin is in a state of intense fluidization, forming a certain thickness of fluidized bed. While eliminating the feed cone and segregation phenomenon, a large amount of water is pre-dried by using the large amount of hot air provided by the high-temperature hot air. Due to the large amount of water removed and the high inlet air temperature, the inlet air can even use gas without dehumidification. In addition, when the material is in a high-moisture stage, the tendency of caking and scarring is greater. The high turbulence and high backmixing characteristics of the material in the fluidization have a good dispersion and breaking effect on the wet material. After the moisture of the material is reduced, the caking and scarring characteristics of the material also decrease accordingly, which is beneficial to reduce the caking and scarring phenomenon of the material entering the drying heat exchanger section. Compared with the lower first fluidizing wind gas distribution assembly, the material layer above the upper first fluidizing wind gas distribution assembly is lower, and the power consumption required by a large amount of air supply is also less, thereby reducing the energy consumption required by the air supply.

[0191] In cooperation therewith, a smaller amount of hot gas or hot dry gas is passed into the downward first fluidizing wind gas distribution assembly 4, but the material in the heat exchanger zone is still in a good fluidization state, and the corresponding fluidization number is greater than 1. While utilizing the high heat transfer and mass transfer rate in the fluidization state to dry the material efficiently, the phenomenon of material caking or scarring on the heat exchanger wall is avoided.

[0192] In cooperation therewith, when the two-layer first fluidizing wind gas distribution assembly 4 is used to pass in hot air for material drying operation, the flow rate of the gas passed in is very large, so the feed section is often set as a shell with an enlarged section, that is, the lower shell of the feed section is a shell with a rectangular cross section, the upper shell is an enlarged rectangular cross section, and the shell between the upper and lower shells is a tapered shell. The material is usually located in the lower shell in the working state, and the upper part of the material layer has a certain height of the tapered shell and the rectangular upper shell as a gas-solid separation space. Since the wind speed gradually decreases during the upward process of the tail gas, more small particles entrained in the tail gas re-settle in the space, so that only fine powder is taken away from the tail gas. Therefore, it can work at a higher fluidization speed without increasing the amount of particles entrained by the tail gas.

[0193] In the present 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 are improved as follows:

[0194] 1. The total amount of air flow from the first fluidization air gas distribution assembly 4 at the lower side of the drying heat exchanger assembly 2 plus all the air flow from the lower housing is enough to produce a fluidization air speed of about 0.4 m / s, which corresponds to a fluidization number of about 1.9, in the material layer area where the drying heat exchanger assembly 2 is located, so that the material layer is in good fluidization, and there is no need to further increase the air flow. At the same time, the air flow from the first fluidization air gas distribution assembly 4 at the upper side of the drying heat exchanger assembly 2 itself produces a fluidization air speed of up to 0.6-1.1 m / s, which corresponds to a fluidization number of 2.9-5.2, and the total air flow through the material layer above produces a fluidization air speed of 1.0-1.5 m / s, which corresponds to a fluidization number of about 4.8-7.1, and the corresponding bed height is 500-700 mm. In contrast, the bed height through which the air flow from the first fluidization air gas distribution assembly 4 at the lower side needs to pass is more than 2000 mm, and just from the perspective of energy saving, more than 15 kw of power consumption can be saved. Because of the use of the enlarged section design, the cross-sectional area of the enlarged section is twice that of the lower straight section, so the air speed of the enlarged section is not increased, and the tail gas entrainment is not increased.

[0195] 2. Due to the increase in the air flow of the drying section inlet, the material layer is in a state of intense fluidization, and there is no heat exchanger above the first fluidization air gas distribution assembly 4, so there is no need to worry about the problem of scabbing, and the moisture content of the feed material is increased from 2.5-3% to about 4%. The fluidized bed granulator (granulation bed) used for 70% lysine prilling generally includes a prilling and drying section and a deep drying section, and the moisture content of the prilled and dried particles is reduced from about 5% to 2.5-3% before being discharged from the granulation bed. In Example 2, due to the increase in the moisture content of the feed material of the fluidized drying section 100, the final moisture content requirement of the discharge material of the deep drying section of the granulation bed can be significantly reduced, thereby reducing the tail gas temperature of the granulation bed, and avoiding excessive drying of particles outside the qualified particle size (the yield of the granulation bed is generally 40-70%) in the granulation bed, thereby saving energy consumption.

[0196] Example 3

[0197] As shown in Figure 3 , the difference between this example and Example 1 is that this example can be extended as follows: multiple layers of drying heat exchanger assemblies 2 can be arranged in series in the fluidized drying section 100, with each layer of drying heat exchanger assembly 2 including multiple heat exchangers 31 arranged in parallel.

[0198] When steam heat source is used, parallel mode is used for heat supply, i.e. steam is independently connected to the heat source inlet manifold of each heat exchanger from the heat source main pipe, and the condensed water produced in the heat exchange process is independently connected to the condensed water main pipe. When hot water, heat conducting oil and other heat sources are used, series mode can be used for heat supply, i.e. the heat source is connected from the bottom heat source inlet distribution main pipe, sequentially connected into the multi-layer drying heat exchanger assembly 2, and finally discharged from the top heat source outlet distribution main pipe, so as to increase the total temperature difference of the heat source inlet and outlet, and reduce the heat source flow; or the heat source can be supplied in parallel mode as the steam heat source, so as to increase the temperature difference between the heat source and the material, and further reduce the final moisture of the material.

[0199] When the multi-layer drying heat exchanger assembly 2 and the cooling heat exchanger assembly 3 are provided, the tubular heat exchanger and the plate heat exchanger can be used in different drying sections or cooling sections, preferably, the extension directions of the heat exchange pipes or the heat exchange plates of all layers are the same in the horizontal direction, and the heat exchange pipe groups or the heat exchange plate groups of the upper and lower adjacent heat exchanger assemblies are arranged in staggered manner in the vertical direction, specifically, the staggered arrangement of the heat exchange pipes is as shown in Figure 8 , the staggered arrangement of the heat exchange plates is as shown in Figure 9 , and the staggered arrangement of the tubular heat exchanger and the plate heat exchanger when they are adjacent in the vertical direction is usually as shown in Figure 5 . The arrangement can make the material flowing downward in the first material channel 1000 formed between the adjacent heat exchange pipes or the adjacent heat exchange plates of the previous heat exchanger assembly be distributed into two adjacent first material channels 1000 when entering the next heat exchanger assembly, so as to increase the lateral movement of the material, break the slight adhesion phenomenon between the materials, increase the mixing of the materials between different temperatures, and improve the uniformity of the material temperature.

Claims

1. A drying and cooling all-in-one machine, characterized in that: The shell body (1), the drying heat exchanger assembly (2), the cooling heat exchanger assembly (3), the gas distribution assembly, the gas supply system and the 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 the first material passage (1000) is arranged between the heat exchange plates or the heat exchange tubes of the drying heat exchanger assembly (2) and the cooling heat exchanger assembly (3); The gas distribution assembly is horizontally arranged in the shell body (1) and comprises the air distribution units (2000) and the second material passages (3000) arranged between the air distribution units (2000); The shell body (1) is a vertical shell, and the top of the shell body (1) is provided with the feeding port (101) and the exhaust port (102), and the bottom of the shell body (1) is provided with the discharging port (103); The shell body (1) is provided with the fluidized drying section (100), the fluidized cooling section (200) and the gravity cooling section (300) from top to bottom; The fluidized drying section (100) is provided with the drying heat exchanger assembly (2) connected with the heat exchange medium supply system; The fluidized cooling section (200) and the gravity cooling section (300) are provided with the cooling heat exchanger assembly (3) connected with the heat exchange medium supply system; The heat exchange medium supply system is used for supplying the heat medium and the cold medium to the drying heat exchanger assembly (2) and the cooling heat exchanger assembly (3) respectively; The gas distribution assembly comprises the first fluidized air gas distribution assembly (4) and the second fluidized air gas distribution assembly (5) arranged in the fluidized drying section (100) and the fluidized cooling section (200) respectively, and the first fluidized air gas distribution assembly (4) and the second fluidized air gas distribution assembly (5) are connected with the gas supply system respectively; The first fluidized air gas distribution assembly (4) is used for supplying the hot dry gas or the hot gas not dehumidified by the gas dehumidification device into the shell body (1), and the ventilation amount of the first fluidized air gas distribution assembly (4) is combined with the ventilation amount of the second fluidized air gas distribution assembly (5), so that the material in the fluidized drying section (100) is in a fluidized state; The second fluidized air gas distribution assembly (5) is used for supplying the dry gas into the shell body (1), so that the material in the fluidized cooling section (200) is in a fluidized state.

2. The integrated drying and cooling machine of claim 1, wherein: The fluidized cooling section (200) and the gravity cooling section (300) are provided with two or more layers of cooling heat exchanger assemblies (3) from top to bottom, each layer of cooling heat exchanger assembly (3) forms a cooling section, and the temperature of the cold medium of each layer of cooling heat exchanger assembly (3) decreases from top to bottom.

3. The drying and cooling all-in-one machine according to claim 1 or 2, characterized in that: 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, pressure and / or temperature of the heat exchange medium in the heat exchanger assembly connected therewith.

4. The integrated drying and cooling machine of claim 2, wherein: The gas distribution assembly further comprises the replacement air gas distribution assembly (6) arranged in the gravity cooling section (300) and connected with the gas supply system; The replacement air gas distribution assembly (6) is used for supplying the dry gas into the shell body (1). A layer of replacement air distribution assembly (6) is arranged below each layer of cooling heat exchanger assembly (3) in the gravity cooling section (300).

5. The integrated drying and cooling machine of claim 1, wherein: The auxiliary bin (7) is connected with the inlet (101) and the outlet (103).

6. The integrated drying and cooling machine of claim 1, wherein: The bin level meter (8) and the adjustable discharge device (9) are further included. The bin level meter (8) is arranged on the top of the shell body (1) and used for measuring the material level in the shell body (1). The discharge device (9) is connected with the outlet (103) and used for adjusting the discharge speed of the material to control the material level in the shell body (1).

7. The integrated drying and cooling machine of claim 4, wherein: 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 device is used for removing the moisture in the gas to obtain dry gas, and the gas cooling device is used for controlling the temperature of the dry gas entering the fluidization cooling section (200) and the gravity cooling section (300). The gas heating device is used for heating the dry gas entering the fluidization drying section (100) or the gas not dehumidified by the gas dehumidification device. The fluid pressure / flow control device is used for controlling the pressure or flow of the heat medium or the cooling medium. The fluid heating device is used for heating the liquid heat medium. The fluid cooling device is used for controlling the temperature of the cooling medium to avoid the moisture absorption, caking or scabbing of the material on the wall of the heat exchanger.

8. The integrated drying and cooling machine of claim 1, wherein: The air distribution unit (2000) includes a gas distribution pipe (11), and the air distribution pipe (11) is provided with air distribution holes (111) below. The air distribution holes (111) are arranged in rows along the axial direction of the air distribution pipe (11) and are spaced apart from each other, and at least one row of air distribution holes (111) is arranged below each air distribution pipe (11).

9. The integrated drying and cooling machine of claim 8, wherein: The air distribution pipe (11) is a straight pipe.

10. The integrated drying and cooling machine of claim 8, wherein: The air distribution pipe (11) is perpendicular to the heat exchange pipe in the drying heat exchanger assembly (2) or the cooling heat exchanger assembly (3), or the air distribution pipe (11) is perpendicular to the heat exchange plate in the drying heat exchanger assembly (2) or the cooling heat exchanger assembly (3).

11. The integrated drying and cooling machine of claim 8, wherein: The opening ratio of the first fluidization air distribution assembly (4) and the second fluidization air distribution assembly (5) is greater than that of the replacement air distribution assembly (6).

12. The integrated drying and cooling machine of claim 8, wherein: The opening ratio of the air distribution hole (111) below the feed inlet (101) of the uppermost layer of the first fluidization air distribution assembly (4) is greater than that of the air distribution hole (111) not below the feed inlet (101) of the uppermost layer of the first fluidization air distribution assembly (4).

13. The integrated drying and cooling machine of claim 1, wherein: The drying heat exchanger assembly (2) or the cooling heat exchanger assembly (3) includes a plurality of heat exchange pipes arranged in the horizontal direction, and the heat exchange pipes are serpentine pipes extending upward and downward.

14. The integrated drying and cooling machine of claim 13, wherein: Two adjacent serpentine heat exchange pipes are arranged in a staggered manner upward and downward.

15. The integrated drying and cooling machine of claim 1, wherein: The drying heat exchanger assembly (2) is a tubular heat exchanger.

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