Large rectangular continuous spraying fluidized bed device

Abstract

The utility model discloses a large rectangular continuous spray fluidized bed device, and relates to the technical field of spray fluidized bed granulation equipment. Comprising a rectangular fluidized bed, the length of the fluidized bed is more than three times larger than the width of the fluidized bed, and an air distribution chamber, an air distribution screen plate, a fluidization chamber and a separation chamber are sequentially arranged in the fluidized bed from bottom to top. The side spray guns are mounted on one side or two sides of the fluidized bed; and a two-dimensional liquid-solid mixing replacement effect which is better than a single liquid-solid mixing replacement effect is formed through the cross atomization flow combination effect of the transverse spray flow of the side spray gun and the up-down spray flow of the top spray gun.

Description

Technical Field

[0001] The utility model relates to the technical field of spray fluidized bed granulation equipment, in particular to a large rectangular continuous spray fluidized bed granulation and drying device. Background Technique

[0002] In the prior art, for the fluidized bed device used for spray fluidized bed granulation and drying of seeds (mother nuclei, bottom materials) (abbreviated as fluidized bed granulation), the fluidized material layer, i.e., the fluidized material bed, can be adjusted or specifically designed according to different functions to selectively meet the production requirements of four types of particles: snowflake shape, golden sugar flat shape, quasi-spherical shape, and spherical shape. When the seeds are continuously fed into the fluidized bed or / and seeds are generated in the fluidized bed, and the granular materials are continuously discharged from the fluidized bed, a continuous spray fluidized bed is formed. The granulation principle is divided into agglomeration and coating. In the fluidized bed, agglomeration and coating coexist simultaneously, with different proportions. Because there are many Chinese meanings, sometimes coating is also called coating, cladding, etc. Sometimes, to meet the required amount of seeds, a part of the finished product can be returned as seeds (which can be broken or not). When the seeds are returned from outside the main body of the fluidized bed, there can be a dedicated feed port, or it can share and merge with other housing connection ports, such as the seed return port for cyclone collection and discharging, the seed return port for bag collection and powder return, the seed return port after screening, and the seed feeding port for feeding the bottom material at startup (such as manual feeding port, pneumatic feeding port, mechanical conveying feeding port), etc. The solid components of the seeds and the raw material liquid can be the same or different.

[0003] Such fluidized beds usually have several unit fluidization chambers and several separation chambers. The separation chambers are above the fluidization chambers. Mother liquor nozzles are provided inside or above the fluidized material layer. The air inlet chamber, fluidization chamber, and separation chamber may or may not correspond one by one. It can be a single-unit structure or a multi-unit structure. Between the fluidization chambers corresponding to the upper part of the air inlet chamber, there may or may not be a partition. When there is no partition, the corresponding area of the air inlet chamber can be called the corresponding unit fluidization chamber and separation chamber. The partition can completely block and only leave a material flow port, or it can not be blocked or even just be a small area in the fluidization chamber. When the fluidized bed is working, there is a fluidized material layer. The height (pressure difference) of the fluidized material layer changes under the comprehensive influence of the material inventory in the fluidized bed, fluidization air velocity, fluidization state, designed fluidization operation route, particle morphology, etc. The fluidized material layer can be only in the fluidization chamber, or it can expand or be thrown into the separation chamber. As long as the fluidized material does not run out of the fluidized bed housing in large quantities, it can work normally. The material inventory can be adjusted according to the specific process requirements. The fluidization chamber has various forms such as a straight section, an enlarged section, and a combination of a straight section and an enlarged section.

[0004] Large fluidized beds are usually rectangular in shape. If the local position of the air distribution plate of the fluidized bed is arc-shaped and the included angle on both sides may not be 90 degrees, such as being diamond-shaped, as long as one side length of the air distribution plate of the fluidized bed is greater than the other side length, it is considered to belong to a rectangular fluidized bed. A drying fluidized bed and a cooling fluidized bed can be integrally connected adjacent to the spray fluidized bed in sequence to form an integrated unit. The difference is that a spray gun is installed in the spray fluidized bed, while there is no spray gun in the drying and cooling fluidized beds. When the spray fluidized bed, the drying and cooling fluidized beds are continuous as a whole, the widths of their respective air inlet chambers, fluidization chambers, and separation chambers can also be unequal.

[0005] The particle swarm in the fluidized state belongs to the continuous phase or the dense phase, and the dispersed bubbles are the dispersed phase or the dilute phase. When there is an obvious upper interface in the fluidized bed layer, the coexistence of the dense and dilute phases is relatively uniform, and there are no obvious large bubbles, which is the dense-phase fluidized bed or dispersed fluidization; small bubbles merge during the rising process and break when rising, especially above the fluidized bed layer. Some particles will be thrown up, even very high. Due to the rising, merging, and breaking of bubbles, this throwing-up phenomenon is relatively obvious. At this time, there is no stable upper interface (that is, the upper interface cannot be measured and observed), and this fluidized state is called aggregative fluidization. Usually, both dispersed and aggregative fluidization exist simultaneously in the fluidized material layer, that is, the phenomena of bubble merging and breaking always occur, with different proportions. When the proportion is large, such as only a few or one large bubble, an adverse state of slugging may even occur. When the proportion is small, that is, when dispersed fluidization is dominant, it can be considered to have an upper interface similar to the stable boiling of a liquid. Although there are countless small bubbles, the throwing-up phenomenon is small and can be considered non-existent, and the average height of boiling can be taken as the upper interface. Due to the breaking of bubbles at the interface of dense-phase contact, there will be violent impacts between particles, resulting in large turbulence both inside and outside the bubbles, thus strengthening the heat and mass transfer between gas and solid and between particles. Therefore, it can be known that the heat and mass transfer at the bubble-breaking point is greater than that at the non-bubble-breaking point, and the heat and mass transfer of multiple small bubbles is better than that of a small number of large bubbles, which is more conducive to fluidization stability.

[0006] The spray fluidized bed is based on the fluidized bed. However, due to the existence of the spray gun and the spray flow, especially the air-atomizing spray gun, there is a gas-liquid flow (spray flow) that atomizes the raw material liquid with atomizing air, resulting in a difference in the state of the fluidized material layer from that of the fluidized bed. For example, when there is an internal heater and the height of the fluidized material layer is relatively high, this difference will be more obvious, leading to deviations in the fluidization state and principle between fluidized bed granulation and fluidized bed drying. Therefore, some principles in fluidized bed drying books can only be used for reference and cannot be directly applied to the spray fluidized bed. For example, for a fluidized material layer with the same particle size, in the spray fluidized bed, the operating fluidization velocity is usually greater than that in fluidized bed drying to be more conducive to the mutual adhesion resistance of the particles in the fluidized material layer and avoid the occurrence of dead beds or caking phenomena.

[0007] According to the atomization direction of the nozzle, the spray route can be divided into three basic direction routes. Bottom spraying means spraying from bottom to top, side spraying means spraying from one side of the housing to the other side, and top spraying means spraying from top to bottom. Side spraying can be divided into upper side spraying located above the material layer height position, middle side spraying located in the middle of the material layer height position, and lower side spraying located below the material layer height position according to different installation height positions. Usually, only one spray route is set for a fluidized bed, that is, there is only one (one-dimensional) direction of spray flow, and the liquid-solid mixing and displacement effect of the fluidized bed layer is single. It can also be known from the fluidization state that during aggregative fluidization, there are particle clusters being thrown up, and there are also particle clusters and bubble clusters inside the fluidized material layer. At this time, the sprayed spray flow (such as gas-liquid flow), if directly sprayed into the uneven particle cluster and bubble cluster area, is not conducive to the dispersion of particles, easily passes through the bubble cluster, resulting in easy adhesion between particles, especially small particles, slow particle replacement, resulting in non-dense finished particles and a decrease in bulk density, a decrease in the heat and mass transfer efficiency between the fluidizing gas and particles, and even the gas-liquid flow, after passing through the fluidized material layer, reaches the opposite wall in the spray flow direction, directly causing wall caking and dead bed.

[0008] After a large number of engineering summaries and tests by the applicant, during spray fluidized bed granulation, when the length of the fluidized bed is more than 3 times its width (the length and width of the fluidized bed generally refer to the net length and net width dimensions of the air distribution plate of the fluidized bed, used to describe the representative dimensions and meanings of the fluidized bed), it shows obvious rectangular characteristics. Along the length direction of the fluidized bed, the height of the fluidized material layer will suddenly exhibit large waves or even seesaw phenomena. However, in ordinary drying or cooling fluidized beds, such waves and seesaw phenomena are difficult to occur or do not occur at all. This also indicates that the spray fluidized bed is different from the fluidized bed drying. When the seesaw phenomenon is relatively severe, the fluidization will become slow or even dead bed at a relatively high position of the fluidized material layer, and at a relatively low position of the fluidized material layer, the fluidization will accelerate, even blow through (or fluidize too fast), resulting in a large amount of materials being thrown up or even being carried out of the fluidized bed shell by the process air, and subsequent blockages will occur in, for example, the cyclone separator, causing it to be unable to work. The height of the fluidized material layer described here, in addition to manual observation, common measurement and feedback schemes are as follows: For example, if the inlet air chamber is under positive pressure and the separation chamber is under negative pressure, when there are more than 2 inlet air chambers, during the operation of the spray fluidized bed, 1 wind pressure point is installed in each inlet air chamber. If the separation chamber is connected, 1 common wind pressure point is set in the separation chamber. The wind pressure in each inlet air chamber minus the wind pressure in the separation chamber is equal to the measured pressure difference of the material layer (corresponding to each inlet air chamber, including the wind pressure difference of the air distribution mesh plate). The measured pressure difference of the material layer shows inconsistency along the length direction of the fluidized bed. When the measured pressure difference of the material layer fluctuates up and down by more than a certain value, it can be judged that large waves or even seesaw phenomena have occurred in the fluidized material layer along the length direction of the fluidized bed. For example, when the bulk density of the material is 600 kg / m3, when the pressure difference of the material layer shows an up and down change with an error of 1000 - 1500 Pa, the greater the change, the more likely a sudden dead bed phenomenon will occur. Fluctuations of the front and back material layer pressure differences within the range of 300 - 600 Pa are all small waves. Although not ideal, they will not cause sudden dead bed problems. Small fluctuations of the material layer pressure difference within the range of less than 300 Pa belong to the ideal stable state and can work very stably.

[0009] When the seesaw phenomenon occurs, there are other disadvantages. Because the spray gun is usually fixed and difficult to adjust, the height of the fluidized material layer changes with the seesaw phenomenon, resulting in changes in the designed spray gun atomization position relative to the upper and lower heights of the fluidized material layer, which destroys the original design process and fluidization effect, affects the particle morphology and bulk density, and also affects the spray gun atomization state. As mentioned above, it also affects the heat and mass exchange effect between the spray flow and the fluidized particles. For example, if the spray gun is sprayed from the upper side, it is more sensitive to the height of the material layer. When the material layer height becomes lower, it will directly spray onto the opposite shell wall. When the material layer becomes higher, it will not spray from the upper side. If it is top sprayed above the fluidized material layer, as the material layer height changes, the distance between the spray gun mouth and the upper interface of the dense phase changes, which has a direct impact on the particle morphology, and the degree of the "spray drying" phenomenon of the top spray will also change. Therefore, when the height of the fluidized material layer changes with the seesaw phenomenon, the ratio of agglomeration and coating granulation in the example of upper side spraying or top spraying will change accordingly. In addition, the change in the height of the fluidized material layer is not conducive to the operation of the bottom spraying fluidized bed. The other spray routes will also have adverse effects. For example, if an internal heater is installed above the lower spray gun, the change in the material layer height will affect the heat exchange and fluidization state of the internal heater. I will not give examples one by one.

[0010] The above shortcomings, in a large rectangular fluidized bed, because of the single spray route, will lead to unstable operation of the spray fluidized bed (large waves and seesaw phenomenon may occur suddenly), single liquid-solid mixing and replacement effect of the fluidized bed, reduced internal heat and mass exchange efficiency, uneven particle morphology (for example, when the agglomeration form increases, the bulk density will decrease), and even local fluidization slowdown, or even fluidized bed dead and unable to operate. After a lot of scientific research by the applicant, some solutions and measures have been adopted to realize a large rectangular continuous spray fluidized bed device, which can avoid or greatly reduce this seesaw phenomenon, turning large waves into small waves or a stable state, and achieving stable continuous operation. Utility Model Content

[0011] The utility model aims to provide a large rectangular continuous spray fluidized bed device, which can avoid the sudden appearance of large waves or seesaw phenomena in the fluidized material layer in the length direction of the fluidized bed, reduce the large waves that may be generated due to various exciting forces when the spray fluidized bed is working into small waves or a stable fluidized state, and avoid the problems of unstable operation of the spray fluidized bed, reduced internal heat and mass exchange efficiency, uneven particle shape, and even local fluidization slowdown, spraying onto the opposite wall, large blocks generated inside, fluidized dead bed, and even the inability to run.

[0012] The technical solution for achieving the above object is as follows: A large rectangular continuous spray fluidized bed device includes a rectangular fluidized bed, the length of the fluidized bed being more than 3 times the width of the fluidized bed. Inside the fluidized bed, a wind distribution chamber, a wind distribution screen plate, a fluidization chamber, and a separation chamber are successively arranged from bottom to top. It is characterized in that: Side spray guns and top spray guns for spraying into the fluidized bed are simultaneously installed on the fluidized bed. There are multiple side spray guns and multiple top spray guns. The side spray guns are installed on one side or both sides of the fluidized bed.

[0013] The distance between the centers of the spray nozzles of the side spray guns and the top spray guns in the height direction is 0.35 times to 2 times the height of the fluidized material layer, and the angle between the side spray guns and the horizontal line in the height direction is 0 - 30°.

[0014] The beneficial effects of the present utility model are as follows: After the process air of the spray fluidized bed passes through the fluidized bed layer, the water sprayed by the spray guns will enter the process air and present a gaseous state. Inside the large spray fluidized bed housing, side spray guns and top spray guns are respectively arranged. Through the combined action of the transverse spray flow of the side spray guns and the up-and-down spray flow of the top spray guns, a two-dimensional liquid-solid mixing and displacement effect is formed, which is better than the single liquid-solid mixing and displacement effect. Through the multiple intersections and common actions of the side spray and top spray atomization flows, a damping effect in the length direction is formed, comprehensively reducing or hindering the wavy excitation force along the length direction of the fluidized bed, thereby avoiding or greatly reducing the phenomenon of large waves or seesaw suddenly appearing in the fluidized material layer of the large rectangular fluidized bed granulator, ensuring that the height (pressure difference) of the fluidized bed material layer remains stable in the length direction, realizing high efficiency of heat and mass transfer between particles, fluidized gas, and gas-liquid flow when the spray flow contacts the fluidized material layer, the relative position between the spray guns and the fluidized material layer is relatively stable and more in line with the design conditions, the bubble coalescence in the spray flow influence area may be greatly reduced, the excitation force of the material layer swing caused by the upward throwing phenomenon of the material in the upper part is greatly reduced, and the proportion of dispersed fluidization is more. The particles, especially small particles, in the spray flow influence area are updated faster and the agglomeration is reduced, thereby realizing stable fluidization operation, a large total amount of heat and mass transfer per unit volume, avoiding uneven particle morphology, avoiding bed layer caking and even dead bed faults caused by serious seesaw phenomenon, and achieving the purpose of the utility model. Preferably, the number of unit fluidization chambers provided with cross atomization flow accounts for more than 50% of the total number of unit fluidization chambers for granulation.

[0015] The top spray guns can play the effects of suppressing dust, reducing the exhaust air temperature, and making small particles grow faster than large particles. Since the side spray guns are buried in the fluidized material layer and there is no spray drying, it is beneficial to the spreading and rolling of droplets, that is, beneficial to particle densification. Under the combined action of the multiple cross atomization flows of the top spray guns and the side spray guns, it is more beneficial to particle densification and fluidization stability. The distance between the top spray nozzle and the dense phase interface can be adjusted according to specific needs. When the pressure difference of the material layer is large, this distance may also be negative. It is optimized to make the cross spray flow cover the entire spray fluidization chamber to maximize the damping effect.

[0016] Furthermore, the distance between the side spray gun and the position with the shortest distance between the axes of the spray flows of an adjacent top spray gun is 100 - 500 mm, so that the spray flows of the side spray gun and an adjacent top spray gun form staggered cross-spray flows.

[0017] The setting of the distance between the side spray gun and the adjacent top spray gun, in addition to being more conducive to the realization of the utility model purpose, the horizontal spray flow of the side spray gun and the up-and-down spray flow of the top spray gun can enable the fluidized material layer to form a three-dimensional liquid-solid mixing and displacement effect and a spatial three-dimensional eddy effect (for example, circular or elliptical routes can be formed, and the route directions can be the same or different) in the fluidized bed, and can also make the particles in the atomization zone, especially small particles, displace faster, making it less likely for the fluidized material particles to stick to each other. The inner spray flow and the top spray flow in the fluidized material layer have less influence on each other, thus being more conducive to improving the heat and mass transfer efficiency in the spray zone, more conducive to destroying possible bubble coalescence, further increasing the damping effect and reducing the excitation force source of the interfering wave seesaw.

[0018] Furthermore, an internal heater is provided below the side spray gun, and the distance between the side spray gun and the uppermost heating surface of the internal heater is 100 - 600 mm; through the internal blocking effect of the internal heater, the fluidized material is more conducive to tending towards a dispersed fluidization state, with fewer large bubbles, being more conducive to improving fluidization stability, comprehensively improving the heat exchange efficiency, and reducing the required fluidization air volume.

[0019] Furthermore, the side spray guns and the top spray guns are arranged along the length direction of the fluidized bed, and the average number of side spray guns installed per 3 meters on one side is 1 - 7. Only with a sufficient number of cross-atomization flows can there be more damping effects and the effect of destroying bubble coalescence.

[0020] The fluidization chamber is provided with an enlarged section with the large end facing upwards, and the side spray gun is installed on the enlarged section. The fluidization wind speed in the enlarged section shows a linear decrease, and there are more small particles towards the upper part. The material has a tendency to move towards the inclined shell surfaces on both sides in the enlarged section. Combined, the three-dimensional liquid-solid mixing and displacement effect is better, and together with the above-mentioned three-dimensional operation route result, it forms a similar four-dimensional liquid-solid mixing and displacement effect.

[0021] Furthermore, the fluidization chamber includes a straight section located at the lower part and an enlarged section located at the upper part with the large end facing upwards. The side spray gun is installed on the enlarged section and is inside the upper part of the fluidized material layer; it is more conducive to setting the internal heater on the straight section to play a better combined role. At this time, the side spray gun can also be set on the enlarged section, which is more conducive to achieving a similar four-dimensional liquid-solid mixing and displacement effect.

[0022] Furthermore, the internal heater can be set on the straight section or the enlarged section or simultaneously located on both the straight section and the enlarged section.

[0023] Furthermore, the fluidization chamber adopts an enlarged section with the large end facing upward and no straight section. Inside the enlarged section, since the fluidization wind speed decreases upward, the fluidized material has a tendency to move horizontally towards the shell of the enlarged section, adding an additional flow path. When combined, the three-dimensional liquid-solid mixing and displacement effect is better. Combining with the above three-dimensional flow path results in a similar four-dimensional liquid-solid mixing and displacement effect.

[0024] Furthermore, the top spray gun and the spray flows of the adjacent side spray guns on both sides respectively form a circular or elliptical path, and the top spray gun and the adjacent side spray guns on both sides are arranged in the tangential direction of the corresponding circular or elliptical path; this enhances the particle displacement effect in the spray area and makes it difficult for particles to adhere to each other.

[0025] Furthermore, side spray guns are respectively arranged on both sides of the fluidized bed, and the side spray guns on both sides are staggered in the length direction of the fluidized bed. In the length direction of the fluidized bed, the distance between two adjacent staggered side spray guns is 150 - 600 mm, and more preferably, the adjacent staggered distance is 200 - 400 mm.

[0026] The rubbing effect is formed between the atomization flows of the side spray guns staggered on both sides, which is more conducive to the three-dimensional liquid-solid mixing and displacement effect and the damping effect.

[0027] The present utility model can comprehensively adopt various solutions of the existing other technologies to achieve a better combined effect.

[0028] In summary, in a large rectangular continuous spray fluidized bed device, when the present utility model works, it can avoid or greatly reduce the seesaw problem, change from large waves to small waves or a stable state, and achieve stable continuous operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a front view combined schematic diagram of a main body of the present utility model;

[0030] Figure 2 It is a side view combined schematic diagram of a main body of the present utility model;

[0031] Figure 3 It is a top view combined schematic diagram / sectional view of a main body of the present utility model;

[0032] Figure 4 It is another top view combined schematic diagram / sectional view of a main body of the present utility model;

[0033] Figure 5 It is a side view of a configuration structure of a side spray gun and a top spray gun of the present utility model;

[0034] Figure 6 It is another side view of a configuration structure of a side spray gun and a top spray gun of the present utility model;

[0035] Figure 7Front view of the grille of the present utility model;

[0036] Figure 8 Top view of the grille of the present utility model;

[0037] Figure 9 Schematic cross-section of the grille bars;

[0038] As shown in the figure, where: 1 is the air distribution chamber, 2 is the air distribution grid plate, 3 is the internal heating fluidization chamber, 4 is the spray fluidization chamber, 5 is the separation chamber, 6 is the dust discharge port, 7 is the grille, 8 is the internal heat exchanger, 9 is the side spray gun, 10 is the fluidization chamber, 13 is the discharge port, 14 is the top spray gun, 15 is the return air lock, 16 is the cyclone separator, 20 is the straight section of the fluidization chamber, 21 is the enlarged section of the fluidization chamber, 26 is the air inlet of the granulation bed, 27 is the large rectangular fluidized bed, and 28 is the local eddy current;

[0039] 31 is the length of the fluidized bed, 32 is the width of the fluidized bed, 33 is the schematic of the fluidized material layer, and 39 is the rubbing effect formed between the atomization flows of the side spray guns arranged alternately on both sides;

[0040] 42 is a circular and / or elliptical path, 43 is the horizontal movement trend of the fluidized material towards the enlarged section housing, 44 is the cross atomization flow, and 45 is the schematic of 1 top spray gun corresponding to 4 side spray guns;

[0041] The angle between the side spray gun and the horizontal line;

[0042] The inclination angle of the spray direction of the top spray gun;

[0043] c is the distance between the spray nozzle centers of the side spray gun and the top spray gun in the height direction;

[0044] d is the distance between the grille and the uppermost heating surface of the internal heater;

[0045] e is the distance between the positions with the shortest distance between the spray axes of the side spray gun and the top spray gun projected on Figure 1 the projection

[0046] f is the distance between the grille and the side spray nozzle in the height direction;

[0047] g is the distance between the side spray nozzle and the uppermost heating surface of the internal heater;

[0048] h is the height of the fluidized material layer;

[0049] i is the inclination angle of the side spray gun in the top view;

[0050] j is the transverse length of the grille holes of the grille;

[0051] l is the longitudinal length of the grille holes of the grille;

[0052] k is the height of the grille bars;

[0053] m is the width of the grid bars;

[0054] n is the width of the cutting edge of the grid bars;

[0055] p is the adjacent staggered distance of the side spray guns in the top view;

[0056] q is the angle between the side wall of the expansion section and the vertical line. Detailed implementation mode Embodiment 1

[0057] As Figures 1 to 9 shown: A large rectangular spray fluidized bed, including a large rectangular fluidized bed 27, the fluidized bed 27 is provided with a dust discharge port 6, and a wind distribution chamber 1, a wind distribution grid plate 2, a fluidization chamber 10, and a separation chamber 5 are sequentially arranged from bottom to top in the fluidized bed. The fluidization chamber 10 includes a spray fluidization chamber 4 and an internal heating fluidization chamber 3 arranged up and down. The spray fluidized bed of the present invention can adopt Figure 2 the side air inlet mode in which the air inlet 26 shown is arranged on the lower side of the fluidized bed 27, or can also adopt the bottom air inlet mode from bottom to top. The wind distribution grid plate 2 can adopt the existing known technology, and the technology with low wind distribution resistance and no material leakage is preferred. The internal heating fluidization chamber 3 and the spray fluidization chamber 4 (the spray fluidization chamber and the internal heating fluidization chamber together constitute the fluidization chamber) can be one of a straight section, a conical section, and a structure of a straight section plus a conical section, and can be single or jointly form the fluidization chamber. The separation chamber 5 can be one of a straight section, a conical section, and a structure of a straight section plus a conical section.

[0058] The length 31 of the fluidized bed is more than 3 times the width 32 of the fluidized bed. The length and width of the fluidized bed 27 are respectively the net length dimension and the net width dimension of the wind distribution grid plate 2.

[0059] Side spray guns 9 are arranged in the fluidized material layer 33. As Figure 1 shown on the right side, the side spray guns can be arranged at different height positions at the same time, and the axes can be not in the same vertical plane. The muzzles of the side spray guns 9 extend into the fluidized material layer 33. A top spray gun 14 for spraying into the fluidized bed 27 is also installed on the fluidized bed 27. The atomized flows 37 of the side spray guns 9 and the top spray gun 14 form a cross atomized flow 44 in the fluidized bed 27. The cross atomized flow 44 of multiple two-dimensional spray routes produces a damping effect on the exciting force of the seesaw. A sufficient number of cross atomized flows 44 can have more damping effects and the effect of destroying bubble coalescence.

[0060] The muzzle of the top spray gun 14 can be in the upper space of the spray fluidization chamber 4 or extend into the spray fluidization chamber 4. When the muzzle of the top spray gun is within 300 mm above and below the theoretical height interface of the spray fluidization chamber 4, that is, in the bubble rupture area, which is conducive to heat and mass transfer. The theoretical height interface is obtained through the following calculation of the height of the fluidized material layer.

[0061] The distance c between the centers of the nozzles of the side spray gun 9 and the top spray gun 14 in the height direction is 0.35 to 2 times the height of the fluidized material layer, preferably 0.4 to 1.5 times.

[0062] The calculation formula for the height h of the fluidized material layer (unit: mm) is: h = (measured pressure difference of the material layer * 0.9) * 2 / (bulk density * 10). The unit of the measured pressure difference of the material layer is Pa, and the bulk density is tons per cubic meter. For example, when the bulk density is 0.6 tons per cubic meter, a material layer pressure difference of 6000 Pa represents a fluidized material layer height h = 1800 mm.

[0063] The methods for measuring the bulk density are as follows: Volume method: By measuring the volume and mass of the piled-up material, the bulk density is calculated. This method requires the use of specialized measuring instruments such as a bulk density meter. Weighing method: By measuring the mass and volume of the piled-up material, the bulk density is calculated. This method requires the use of instruments such as a balance and a graduated cylinder.

[0064] The measured pressure difference of the material layer includes the pressure difference of the air distribution plate. The pressure difference of the air distribution plate usually takes 10% of the measured pressure difference of the material layer. Therefore, the pressure difference of the material layer height (material layer pressure difference) is approximately equal to the measured pressure difference of the material layer * 0.9.

[0065] The side spray gun 9 is installed on one or both sides of the fluidized bed 27. The average number of side spray guns 27 installed per 3 meters on one side is 1 - 7, preferably 2 - 6 per 3 meters. The angle a between the side spray gun 9 and the horizontal line is less than 30°, preferably 0° - 15°.

[0066] The atomization flow setting method of the top spray gun 14 is relatively diverse. The top spray gun 14 sprays downward. Specifically, it can be installed on the top of the separation chamber 5 or on the side of the fluidized bed 27. The top spray gun 14 sprays downward. The spray direction can be vertically downward, or inclined towards the center in the width direction of the fluidized bed 27 (in this case, the nozzle is located on one side in the width direction of the fluidized bed 27), or inclined towards one side in the length direction of the fluidized bed 27, or inclined towards one side in both the width direction and the length direction of the fluidized bed 27 at the same time. When the spray direction of the top spray gun 14 is inclined towards one side in the width direction and the length direction of the fluidized bed 27, the inclination angle b is not greater than 30°.

[0067] When the top spray gun 14 is installed on the top of the fluidized bed 27, it can be installed in one row or multiple rows. The number of top spray guns 14 installed per 3 meters in the length direction of the fluidized bed 27 in each row is 1 - 7.

[0068] The side spray gun 9 and the top spray gun 14 have different combination methods. For example, 1 side spray gun 9 can correspond to 1 - 7 top spray guns 14 in terms of quantity, and 1 top spray gun 14 corresponds to 1 - 7 side spray guns 9 in terms of quantity, which is used to adjust the comprehensive use effect and the functional ratio of the side spray gun 9 and the top spray gun 14.

[0069] The side spray gun 9 and the top spray gun 14 will form various combined spray flow routes, such as Figure 2 As shown, for example, 1 side spray gun 9 corresponds to 1 top spray gun 14. In the side view section, the spray flow of the side spray gun 9 and the spray flow of the top spray gun 14 can form a circular or elliptical route 42. The atomized flows of the side spray gun 9 and the top spray gun 14 are tangent upward to the circular or elliptical route. The rotation directions of the two circles or ellipses can be the same or opposite in adjacent side view sections. Further, by controlling the spray directions of the top spray gun 14 and the side spray gun 9, the rotation directions of the circular or elliptical trajectories formed by adjacent cross spray flows can be made opposite, and the overall effect and three-dimensional mixing effect are better. The combination of specific spray direction control means is common knowledge to those skilled in the art and will not be elaborated here.

[0070] For example Figure 5 As shown, 2 side spray guns correspond to 2 top spray guns, forming the effect of multiple cross spray flows in the side view section. Figure 6 As shown, 2 side spray guns 9 correspond to 3 top spray guns 14, and the cross spray flows are more evenly distributed in the fluidized bed 27. Specific examples will not be given one by one here.

[0071] Such as Figure 1 As shown, the distance between the side spray gun 9 and the position with the shortest distance between the axes of the spray flow 37 of an adjacent top spray gun 14 is 100 - 500 mm. Figure 1 The marked e is the projection of this distance on Figure 1 This forms an alternating cross spray flow 44 between the side spray gun 9 and the spray flows 37 of the two adjacent top spray guns 14, with a three-dimensional liquid-solid mixing and displacement effect and a spatial three-dimensional eddy current effect (such as a circular or elliptical route that can have the same or different route directions). It can also make the particles in the atomization zone, especially small particles, be displaced faster, making it less likely for the fluidized material particles to stick to each other. The mutual influence between the inner spray flow 37 and the top spray flow 37 in the fluidized material layer 33 becomes smaller, which is more conducive to improving the heat and mass transfer efficiency in the spray area, more conducive to destroying possible bubble coalescence, further increasing the damping effect, and reducing the source of the exciting force of the interfering wave seesaw. Since there are many combinations of the side spray gun 9 and the top spray gun 14, various combined routes of adjacent and alternating spray flows will be formed. Besides the basic purpose, other functional routes can be generated. For example, see Figure 3On the left side, the combination 45 is 1 top spray gun corresponding to 4 side spray guns, and is located at the center of the 4 side spray guns, forming 4 adjacent staggered cross atomization flows; by analogy, 1 side spray gun can correspond to 1-7 top spray guns, and 1 top spray gun corresponds to 1-7 side spray guns in various spatial stereoscopic situations, and the specific situations are not given one by one. When the distance between the axis of the spray flow of the side spray gun and an adjacent top spray gun at the shortest position is 0-100mm, it is directly opposite (when the distance is 0) or approximately directly opposite (when the distance is greater than 0 and less than 100), and the basic purpose of the utility model can also be achieved.

[0072] The utility model is characterized in that after the process air of the spray fluidized bed passes through the fluidized bed layer 33, the moisture sprayed by the spray gun will enter the process air and present a gas state. In the large-scale spray fluidized bed shell 27, side spray guns 9 and top spray guns 14 are respectively arranged. Through the combined effect of the cross-atomized flow of the lateral spray flow 37 of the side spray gun 3 and the upper and lower spray flows 37 of the top spray gun 14, a two-dimensional liquid-solid mixing and replacement effect is formed, which is better than a single liquid-solid mixing and replacement effect. Through the multiple cross-existence and joint action of the side spray and top spray flows, a damping effect is formed in the length direction of the fluidized bed 27, which comprehensively reduces or hinders the wave motion along the length direction of the fluidized bed. Shaped exciting force, thereby avoiding or greatly reducing the sudden appearance of large waves or seesaw phenomenon in the fluidized material layer 33 of the large rectangular fluidized bed granulator, ensuring that the height (pressure difference) of the fluidized bed material layer 33 remains stable in the length 31 direction, and realizing that when the spray flow 37 contacts the fluidized material layer 33, the heat and mass exchange between the particles and the fluidizing gas and the gas-liquid flow remains highly efficient, and the position of the spray gun and the fluidized material layer 33 is relatively stable and more in line with the design conditions, thereby achieving stable fluidization operation, a large total amount of heat and mass exchange per unit volume, avoiding uneven particle morphology, avoiding bed agglomeration and even dead bed failure caused by serious seesaw phenomenon, and achieving the purpose of the utility model. It is preferred that the number of unit fluidized chambers for setting cross-atomization flow should account for more than 50% of the total number of unit fluidized chambers for granulation, and the cross-atomization flow 44 can also merge the bubbles above the fluidized material layer, greatly reduce the phenomenon of material throwing up, and the proportion of dispersed fluidization is higher, which is another factor that can keep the bed stable.

[0073] The top spray gun 14 can suppress dust, reduce the exhaust temperature, and make small particles grow faster than large particles. Because the side spray gun 9 is buried in the fluidized material layer 33, there is no spray drying, which is beneficial to the spreading and calendering of droplets, that is, it is beneficial to particle compaction. Under the joint action of multiple cross-atomized flows 44 formed by the top spray gun 14 and the side spray gun 9, it is more conducive to particle compaction and fluidization stability. The distance between the muzzle of the top spray gun 14 and the dense phase interface can be adjusted according to specific needs. When the pressure difference of the material layer is large, this distance may also be negative. The most optimized is that the spray flow 37 of the side spray gun 9 and the top spray gun 14 is spread all over the fluidizing chamber 10, so that the cross-atomized flow 44 is spread all over the spray fluidizing chamber 4, and the damping effect is maximized.

[0074] As shown Figure 1 in 2 Figures 5, etc., further, an internal heater 8 is provided below the side spray gun 9. The height distance g between the axis of the side spray gun 9 and the uppermost heating surface of the internal heater 8 is between 100 and 600 mm. Through the internal blocking effect of the internal heater 8, the fluidized material is more conducive to tending towards a dispersed fluidization state, the phenomenon of large bubbles is further reduced, which is more conducive to improving fluidization stability, combining to improve the heat exchange efficiency, and reducing the required fluidization air volume.

[0075] As shown Figure 2 in 5 Figures 7, 8, 9, etc., a grille 7 is provided below the side spray gun 9. As shown Figure 8 in Figure 10, the width m of the grille bars of the grille 7 is between 5% and 16% of the height k, and the material can be made of stainless steel, carbon steel, wear-resistant materials, polymer materials, etc. The characteristics can be changed accordingly with the material characteristics. The distance f between the grille 7 and the muzzle of the side spray gun 9 in the height direction is 100 - 600 mm, which keeps the surface of the particles with a certain plasticity, is conducive to exerting the functions of cutting, rolling, and spreading. When there are both an internal heater and a grille at the same time, the preferred distance d between the grille 7 and the uppermost heating tube of the internal heater is 20 - 200 mm to avoid the thermal influence of the internal heater on the material on the grille.

[0076] The grille holes are usually rectangular. In addition to being conducive to destroying bubbles and promoting dispersed fluidization, the grille bars of the grille 7 stand in the fluidized material layer, and the fluidized material passes through and collides with the grille 7 up and down, which plays the cutting role of a blade. At the same time, the material near the grille 7 is not completely dry, and the surface of the particles has a certain plasticity. At this time, there is a further rolling and spreading effect on the surface of the particles, which is conducive to improving the particle density and dispersing the loose massive materials. The grille 7 can also prevent large pieces from above from falling into the internal heater 8 and causing adverse failures.

[0077] As shown Figure 1 in 8 Figures 11, etc., the grille 7 can also be arranged to incline downward towards the discharge port end 13 with an included angle, which is conducive to promoting the movement of large particles and large pieces towards the discharge port end 13. The transverse length of the grille holes of the grille 7 is j or the longitudinal length of the grille holes is l ( Figure 8 viewing angle). When the heater components (such as but not limited to heating tubes) of the internal heater 8 are arranged along the length direction of the fluidized bed 27, the distance between adjacent two heater components is less than the transverse length j of the grille holes. When the heater components (such as but not limited to heating tubes) of the internal heater 8 are arranged along the width direction of the fluidized bed 27, the distance between adjacent two heater components is less than the longitudinal length l of the grille holes.

[0078] Furthermore, to achieve a better cutting effect, the grid bars of the grid 7 are provided with cutting edges facing upward, downward, or both upward and downward. Preferably, chamfers are provided at the corners of the grid bars in the cross-section to form cutting edges, and the width n of the cutting edges is less than 5 mm.

[0079] In summary, in a large rectangular continuous spray fluidized bed device, when the present invention works, it can avoid or greatly reduce the sudden seesaw phenomenon of the fluidized material layer 33, changing from large waves to small waves or a stable state, and achieve stable continuous operation.

[0080] In summary, after adopting the above various solutions, it is possible to avoid the sudden large wave or seesaw phenomenon of the fluidized material layer 33, reduce the large waves that may be generated due to various excitation forces during the operation of the spray fluidized bed to small waves or a stable fluidized state, avoid unstable operation of the spray fluidized bed, decline in internal heat and mass transfer efficiency, uneven particle morphology, and even problems such as local slowdown of fluidization, spraying onto the opposite wall, formation of large chunks inside, and fluidization dead bed until the operation cannot continue, and avoid the defects of the background technology. Embodiment 2

[0081] As Figure 3 shown, the side spray guns 9 are arranged on both sides of the fluidized bed 27, and the side spray guns 9 on both sides of the fluidized bed 27 are symmetrically arranged, or staggered in the length direction of the fluidized bed, or partially symmetrically arranged and partially staggered in the length direction of the fluidized bed. As Figure 3 The side spray gun 9 on the left side is symmetrically arranged to form a collision effect of the spray flow 37, which is not only beneficial to liquid-solid mixing and replacement, can avoid the spray flow spraying onto the opposite wall, but also increases the spray volume of a single spray gun.

[0082] As Figure 3 The side spray gun 9 on the right side is staggered, and a rubbing effect 39 is formed between the atomization flows of the side spray guns staggered on both sides, which is more beneficial to the three-dimensional liquid-solid mixing and replacement effect and the damping effect. As Figure 4 shown, preferably, in the length direction 31 of the fluidized bed, the distance p between two adjacent staggered side spray guns is 150 - 600 mm, and more preferably, the adjacent staggered distance p is 200 - 400 mm. When not staggered, the basic functions of the present invention can also be achieved. When staggered, it can be equidistant or non-equidistant. As Figure 4 On the left side, when the side spray gun is inclined, the adjacent staggered distance p can also be formed. Embodiment 3

[0083] As Figure 4 shown, there are multiple side spray guns 9 inclined towards one end of the fluidized bed 27, and the inclination angle i is not greater than 30°. Preferably, it is not greater than 20°, so that the spray of the side spray gun 9 can form a planar and inclined local eddy current 28. Multiple local eddy currents can form eddy current deceleration, that is, an eddy current damping effect, which is more beneficial to avoiding the seesaw phenomenon.

[0084] The side spray gun 9 is inclined towards the discharge port end 13 of the fluidized bed 27. At this time, a driving force towards the discharge port end 13 is formed through the spray flow. The driving force and the cross two-dimensional atomized flow act together to form a three-dimensional liquid-solid mixing and displacement effect inside the fluidized material layer. In addition to further enhancing the effect, the large particles inside the fluidized material layer can also be pushed towards the discharge port end 13 through the oblique atomized flow, which is more conducive to continuous and stable operation. When setting, the inclination angles of the side spray guns can be the same, and the distances between them can be equal or unequal. When the inclination angles are the same, a resonance effect can be formed, which can strengthen the heat and mass transfer and damping effect of the planar inclined eddy current.

[0085] Such as Figure 4 As shown in the schematic diagram of the left side spray gun 9, as a further illustration of this embodiment, in this embodiment, some or all of the side spray guns 9 can also be inclined towards the reverse end of the discharge port end 13 of the fluidized bed 27, because when the planar inclined local eddy current 28 is the same in all directions, there will be a certain one-way resistance effect. Similarly, at this time, the side spray guns 9 can be symmetric or asymmetric, the side spray guns 9 can be arranged at equal distances or unequal distances, and they can also be arranged staggeredly to form the above-mentioned staggered effect.

[0086] In summary, there are three inclination combinations of the side spray gun 9 in this embodiment: all inclined towards the discharge port end; all inclined towards the reverse end of the discharge port; some inclined towards the discharge port end and some inclined towards the reverse end of the discharge port, so as to avoid the situation that the height of the material layer at one end of the bed body is always higher than that at the other end due to the one-way effect. Embodiment 4

[0087] Such as Figure 2 、 5 As shown, the fluidization chamber 10 is provided with a straight section 20 and an enlarged section 21 with the large end facing upwards. It is more conducive to setting the internal heater 8 on the straight section 20 to play a better combined role. The side spray gun 9 is installed on the enlarged section 21. The fluidization wind speed inside the enlarged section 21 shows a linear decrease. The more upwards, the more small particles there are. The material has a tendency 43 to move horizontally towards the side inclined side walls in the enlarged section 21, which is more conducive to achieving a similar four-dimensional liquid-solid mixing and displacement effect. Preferably, q is the angle between the side wall of the enlarged section and the vertical line, and q is preferably 10 - 60°. The fluidization wind speed inside the enlarged section shows a linear decrease. The more upwards, the more small particles there are. The material has a tendency to move towards the side inclined shell in the enlarged section. Combined, the three-dimensional liquid-solid mixing and displacement effect is better. Combined with the above three-dimensional operation route results, a similar four-dimensional liquid-solid mixing and displacement effect is formed.

[0088] Furthermore, the internal heater 8 can be set on the straight section 20 or the enlarged section 21 or located inside both the straight section 20 and the enlarged section 21 at the same time.

[0089] In addition, the fluidization chamber 10 can directly adopt the enlarged section 21 without arranging a straight section. Inside the enlarged section 21, since the fluidization wind speed decreases upward, the fluidized material has a movement tendency 43 towards the horizontal of the enlarged section housing, adding an additional operation route. When combined, the three-dimensional liquid-solid mixing and displacement effect is better. Combining with the above three-dimensional operation route results in a similar four-dimensional liquid-solid mixing and displacement effect.

[0090] The terms in the above implementation and layout schemes of the present utility model are all prior arts. This embodiment only describes in detail the inventive content of the present utility model. As is well known to those skilled in the art, for a fluidization device or system, it also needs to be configured or selected with a blower, an air heater, an air inlet pipeline, an air damper, a support platform, a connecting pipe from the main machine to the cyclone separator, a bag filter, a connecting pipe from the cyclone to the bag filter, an induced draft fan, a connecting pipe from the bag filter to the induced draft fan, a water dust collector, a connecting pipe from the induced draft fan to the water dust collector, a control system, instruments. Optionally, there are also commonly used existing configurations such as semi-finished product conveying, a screening machine, a crusher, seed conveying or pneumatic conveying, screw conveying, a rotary air lock valve or an airtight valve, an acceleration pipe, finished product conveying, a finished product bin, and packaging machinery. The cooling device can optionally adopt fluidized bed cooling, drum cooling, a hollow paddle drying and cooling machine, a solid cooler (such as plate type or tubular type, etc.), or a combination of multiple cooling methods. For example, the solid cooler has a plate heat exchanger for powdery and granular solid materials with the patent number ZL201110393598.1. Only in this way can a complete system device be formed, which belongs to conventional technology and will not be elaborated here.

[0091] Appendix Figures 1 to 7 The working process shown is only partial and not all working forms, so no further explanations will be given here.

[0092] Based on the principle of the structure disclosed by the present utility model, those skilled in the art can easily obtain that combining bottom spraying and side spraying, combining top spraying and bottom spraying, and combining top spraying, bottom spraying and side spraying will all have some similar effects, which will not be elaborated here one by one. However, the actual experimental results show that the above combinations are far less effective than the combination of top spraying and side spraying of the present utility model.

[0093] Such as Figure 2 、 5As shown in Figure 6, theoretically, the interface of the material layer can be in the fluidization chamber, at the boundary between the fluidization chamber and the separation chamber, or in the separation chamber. When there is no internal heater 8, theoretically, the interface of the material layer can be lowered to the middle and lower part of the fluidization chamber. The side spray gun can be the upper side spray, middle side spray, or lower side spray described in the background art. The effect of the upper and middle side spray is better than that of the middle and lower side spray because the phenomenon of bubble coalescence, rising, and bursting is more obvious in the upper part of the fluidized material layer. Therefore, when using the upper side spray, the bubble coalescence in the spray flow influence area may be greatly reduced, the exciting force caused by the swinging of the material thrown up in the upper part is greatly decreased, the proportion of particulate fluidization is higher, the renewal of particles, especially small particles, in the spray flow influence area is accelerated, the orderly renewal is accelerated, the agglomeration is reduced, and the heat and mass transfer efficiency is better. At the same time, by adopting technical means to stabilize the swing of the material layer pressure difference from the middle or / and upper part of the material layer, similar to the lever principle, due to the longer force arm, the effect is better than that of the side spray in the middle and lower parts.

Claims

1. A large rectangular continuous spray fluidized bed device, comprising a rectangular fluidized bed, wherein the length of the fluidized bed is more than 3 times greater than the width of the fluidized bed, and a wind distribution chamber, a wind distribution screen plate, a fluidization chamber, and a separation chamber are successively arranged from bottom to top in the fluidized bed, and it is characterized in that: Both side spray guns and top spray guns for spraying into the fluidized bed are installed on the fluidized bed. There are multiple side spray guns and multiple top spray guns. The side spray guns are installed on one side or both sides of the fluidized bed. The distance between the centers of the spray nozzles of the side spray guns and the top spray guns in the height direction is 0.35 to 2 times the height of the fluidized material layer. The angle between the side spray gun and the horizontal line in the height direction is between 0 and 30°. The distance between the shortest position of the axis of the spray flow of the side spray gun and the spray flow of an adjacent top spray gun is 100 - 500 mm, so that the spray flows of the side spray gun and an adjacent top spray gun form an interleaved cross-spray flow.

2. A large rectangular continuous spray fluidized bed device according to claim 1, characterized in that: An internal heater is arranged below the side spray gun. The distance between the side spray gun and the uppermost heating surface of the internal heater is 100 - 600 mm.

3. A large rectangular continuous spray fluidized bed device according to claim 1, characterized in that: The side spray guns and the top spray guns are arranged in a row along the length direction of the fluidized bed. The average number of side spray guns installed per 3 meters on one side is 1 - 7.

4. A large rectangular continuous spray fluidized bed device according to claim 1, characterized in that: The fluidized chamber is provided with an enlarged section with the large end facing upward, and the side spray gun is installed on the enlarged section.

5. A large rectangular continuous spray fluidized bed device according to claim 1, characterized in that: The fluidized chamber includes a straight section at the lower part and an enlarged section at the upper part with the large end facing upward. The side spray gun is installed on the enlarged section and is inside the upper part of the fluidized material layer.

6. A large rectangular continuous spray fluidized bed device according to claim 5, characterized in that: The internal heater is arranged in the straight section or the enlarged section or both in the straight section and the enlarged section at the same time.

7. A large rectangular continuous spray fluidized bed device according to claim 1, characterized in that: The spray flows of the top spray gun and the adjacent side spray guns on both sides respectively form circular or elliptical paths. The top spray gun and the adjacent side spray guns on both sides are arranged in the tangential direction of the corresponding circular or elliptical paths.

8. A large rectangular continuous spray fluidized bed device according to claim 1, characterized in that: Side spray guns are respectively arranged on both sides of the fluidized bed. The side spray guns on both sides are staggered in the length direction of the fluidized bed. In the length direction of the fluidized bed, the distance between two adjacent staggered side spray guns is 150 - 600 mm.

9. A large rectangular continuous spray fluidized bed device according to any one of claims 1-8, characterized in that: A grille is arranged below the side spray gun.

10. A large rectangular continuous spray fluidized bed device according to claim 9, characterized in that: The grid bars of the grille are provided with edges facing upward or downward or both upward and downward at the same time.

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