Spray drying device for strengthening interphase heat transfer

Abstract

The utility model relates to the field of spray drying devices, in particular to a spray drying device for strengthening interphase heat transfer, which comprises a spray drying tower body, an upper section tower body, a middle section tower body, a lower section tower body, a flue gas distribution plate A, a flue gas distribution plate B and a spray gun, an upper section tower body with a conical structure is welded at the upper end of the middle section tower body; a lower section tower body with a conical structure is welded at the lower end of the middle section tower body; the middle-section tower body adopts a cylindrical structure; the utility model provides an innovative flue gas distribution plate trepanning form and a spray gun arrangement form, and the trepanning form of the flue gas distribution plate is adjusted, so that the trepanning circle center position of the large hole in the flue gas distribution plate is overlapped with the axis of the spray gun; high-temperature flue gas is concentrated near the nozzles after passing through the distribution plate and can completely cover liquid drops sprayed by the nozzles, so that the heat exchange efficiency between the high-temperature flue gas and cold slurry is greatly improved under the condition of ensuring reasonable pressure drop in the tower, and meanwhile, large-area adhesion of the slurry in a wet particle state is avoided.

Description

TECHNICAL FIELD

[0001] The utility model relates to a spray drying device field especially relates to a spray drying device of interphase heat transfer enhancement. BACKGROUND

[0002] In industrial production, fluid catalytic cracking process is an important means of crude oil secondary processing, wherein microspherical catalyst is the core of catalytic cracking technology, and spray drying technology is the main technology for drying and granulation of catalytic cracking catalyst.

[0003] The main device of spray drying technology is spray drying tower, which usually involves three stages of atomization of raw material liquid, contact mixing of mist droplets and high-temperature drying medium and separation of dry product and waste gas, wherein the stage most affecting product quality is the contact mixing of mist droplets and drying medium, that is, the drying behavior of mist droplets, research shows that the drying behavior of mist droplets will be affected by operating parameters, for example, when the nozzle is arranged in cross form or centripetal concentrated form, the distance between adjacent droplets is shortened, and the possibility of mutual contact between droplets is increased, which may cause droplets to stick together, which not only causes the particle size of catalyst product to abnormally increase, but also may damage its ideal spherical structure, thereby adversely affecting the subsequent catalytic cracking reaction and reducing the reaction efficiency and the activity of the catalyst; poor contact and uneven mixing of mist droplets and high-temperature flue gas will lead to slow drying rate and low drying efficiency, while increasing the probability of collision between wet particles and dry particles, causing agglomeration between particles and affecting the particle size distribution of catalyst product, therefore, the opening form of the flue gas distribution plate in the spray drying tower and the arrangement form of the spray gun are modified, considering the difficulty of structural modification and the cost of modification, the drying efficiency is improved and the product quality is improved, which has great engineering technical value and social and economic significance for the catalyst granulation industry.

[0004] Therefore, in view of the key problems of low drying efficiency and particle size distribution that cannot meet the requirements of specific process faced by the spray drying tower in current industrial production, a spray drying device for enhancing interphase heat transfer can be designed. Utility model content

[0005] In order to overcome the key problems of low drying efficiency and particle size distribution that cannot meet the requirements of specific process faced by the spray drying tower in current industrial production.

[0006] The utility model discloses a technical scheme for a spray drying device for strengthening inter-phase heat transfer, comprising a spray drying tower body, an upper section tower body, a middle section tower body, a lower section tower body, an air inlet, an air outlet, a flue gas distribution plate A, a flue gas distribution plate B and a spray gun.

[0007] Preferably, the flue gas distribution plate A and the flue gas distribution plate B are arranged in the upper section tower body of the spray drying tower body, for rectifying the tangential high-temperature flue gas into vertical downward flow, thereby avoiding heat loss caused by the concentration of flue gas near the wall surface. The number of large holes on the flue gas distribution plate A and the flue gas distribution plate B is the same as that of the spray gun, and the opening position of the large holes is determined by the spray gun, i.e., the center of the opening coincides with the axis of the spray gun, and the opening area of the large holes is slightly larger than the maximum area of the circle formed by the spray droplets sprayed by the spray gun, so that the high-temperature flue gas is concentrated in the area near the nozzle after passing through the flue gas distribution plate, to ensure that the cold slurry can rapidly exchange heat with the high-temperature flue gas after being sprayed out. The spray gun is arranged vertically downward, to eliminate the adverse effect of the cross arrangement of the spray heads on the product particle size.

[0008] Specific research method: under simulated conditions, the physical model is drawn by using Solidworks software according to the size of each component of the spray drying tower body, the flue gas distribution plate A, the flue gas distribution plate B and the spray gun, and then the mesh is divided by using ICEM software, and the mesh of the spray gun and the flue gas distribution plate A and the flue gas distribution plate B with small size is encrypted to ensure the accuracy of numerical simulation. The material physical parameters are set by literature research, and the operating parameters that can meet the industrial requirements are selected. The drying rate and particle size distribution under the theoretical conditions are obtained by numerical simulation.

[0009] Preferably, the diameter of the air inlet is 1300 mm, the diameter of the air outlet is 1800 mm, and the air inlet and the air outlet are arranged at an angle of 90°.

[0010] Preferably, the spray gun is vertically arranged, the number of spray guns is 8, the spray guns are arranged on a circle with a distance of 3500 mm from the center, the spray guns are arranged at equal intervals in a ring shape, the diameter of the spray gun is 150 mm, the spray gun adopts a pressure type nozzle, and the spray gun extends into the tower by a distance of 300 mm.

[0011] Preferably, the thickness of the flue gas distribution plate A and the flue gas distribution plate B is 200mm; the distance between the flue gas distribution plate A and the flue gas distribution plate B is 1000mm.

[0012] Preferably, the flue gas distribution plate A and the flue gas distribution plate B are provided with large holes on the outer surface; the number of the large holes of the flue gas distribution plate A and the flue gas distribution plate B is the same as the number of the spray guns; the position of the large holes of the flue gas distribution plate A and the flue gas distribution plate B coincides with the position of the center of the spray guns.

[0013] Preferably, the diameter of the flue gas distribution plate A is 9345mm; the diameter of the large hole of the flue gas distribution plate A is 1500mm; the diameter of the flue gas distribution plate B is 10500mm; the diameter of the large hole of the flue gas distribution plate B is 1688mm; the flue gas distribution plate A and the flue gas distribution plate B are provided with small holes with a diameter of 120mm at positions other than the 16 positions coinciding with the spray guns.

[0014] The flue gas distribution plate provided by the utility model has the advantages that:

[0015] The utility model discloses an innovative flue gas distribution plate hole opening form and spray gun arrangement form, which aims at improving the drying efficiency and the quality of catalyst particles simultaneously, thereby effectively solving the problems of low drying efficiency and the particle size distribution failing to meet the requirements of specific processes in the current industrial production.

[0016] By adjusting the hole opening form of the flue gas distribution plate, the hole opening center position of the large hole of the flue gas distribution plate coincides with the axis of the spray gun, the hole opening area is slightly larger than the maximum area of the circle formed by the liquid drops sprayed by the spray gun, small holes are uniformly arranged at the remaining positions, the high-temperature flue gas is concentrated near the nozzle after passing through the distribution plate and can completely cover the liquid drops sprayed by the nozzle, the heat exchange efficiency between the high-temperature flue gas and the cold slurry is greatly improved under the condition of ensuring the reasonable pressure drop in the tower, the vertical arrangement of the spray gun reduces the cross influence between the spray guns, avoids the large-area adhesion of the slurry in the wet particle state, influences the product particle size, and the utility model has the advantages of simple structure and easy realization on the operation level. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 The utility model discloses a spray drying device's spray drying tower three-dimensional structure schematic diagram is shown.

[0018] Figure 2 The utility model discloses a spray drying device's spray gun vertical arrangement form and flue gas distribution plate hole opening form schematic diagram is shown.

[0019] Figure 3 The utility model discloses a spray drying device's flue gas distribution plate A's hole opening form and spray gun arrangement form's plan view is shown.

[0020] Figure 4 The figure shows the top view of the opening form of the flue gas distribution plate B and the spray gun arrangement form of the spray drying device of the utility model;

[0021] Figure 5 The figure shows the single droplet particle size change schematic diagram when the spray drying device of the utility model is drying;

[0022] Figure 6 The figure shows the droplet particle size distribution curve after drying of the spray drying device of the utility model.

[0023] The figure shows the top view of the opening form of the flue gas distribution plate B and the spray gun arrangement form of the spray drying device of the utility model; DETAILED DESCRIPTION

[0024] The utility model is further explained below in combination with the drawings and examples.

[0025] Please refer to Figures 1-6 The utility model provides a kind of example: a kind of spray drying device of interfacial heat transfer enhancement, including spray drying tower body 1, upper section tower body 2, intermediate section tower body 3, lower section tower body 4, gas inlet 5, gas outlet 6, flue gas distribution plate A 7, flue gas distribution plate B 8, spray gun 9;Spray drying tower body 1 includes upper section tower body 2, intermediate section tower body 3 and lower section tower body 4;The upper end of intermediate section tower body 3 is welded with the upper section tower body 2 of conical structure;The lower end of intermediate section tower body 3 is welded with the lower section tower body 4 of conical structure;Intermediate section tower body 3 adopts cylindrical structure;Upper section tower body 2 lateral wall outer side is fixedly connected with cylindrical gas inlet 5;Lower section tower body 4 outlet lower end is fixedly connected with the gas outlet 6 of 90 ° elbow pipe;The inner side of upper section tower body 2 is respectively equipped with flue gas distribution plate A 7 and flue gas distribution plate B 8;Flue gas distribution plate A 7 is located at the upper end of flue gas distribution plate B 8;Flue gas distribution plate A 7 and flue gas distribution plate B 8 opening rate are same and installation position is lower than gas inlet 5;Spray gun 9 is installed in the inner side of upper section tower body 2;Spray gun 9 penetrates flue gas distribution plate A 7 and flue gas distribution plate B 8;Gas inlet 5 diameter is 1300mm;Gas outlet 6 diameter is 1800mm;Gas inlet 5 and gas outlet 6 are 90 ° included angle.

[0026] Please refer to Figure 2 In the embodiment, spray gun 9 is vertically arranged;Spray gun 9 quantity is 8;Spray gun 9 is arranged at the circumference of distance center 3500mm;Spray gun 9 is annular equidistant distribution;Spray gun 9 diameter is 150mm;Spray gun 9 adopts pressure type nozzle;Spray gun 9 is extended into tower distance and is 300mm.

[0027] Please refer to Figure 3 、 4In the embodiment, the thickness of the flue gas distribution plate A7 and the flue gas distribution plate B8 is 200 mm; the spacing between the flue gas distribution plate A7 and the flue gas distribution plate B8 is 1000 mm; the outer surface of the flue gas distribution plate A7 and the flue gas distribution plate B8 is provided with a large hole 10; the number of the large hole 10 of the flue gas distribution plate A7 and the flue gas distribution plate B8 is the same as the number of the spray gun 9; the position of the large hole 10 of the flue gas distribution plate A7 and the flue gas distribution plate B8 coincides with the center position of the spray gun 9; the diameter of the flue gas distribution plate A7 is 9345 mm; the diameter of the large hole 10 of the flue gas distribution plate A7 is 1500 mm; the diameter of the flue gas distribution plate B8 is 10500 mm; the diameter of the large hole 10 of the flue gas distribution plate B8 is 1688 mm; the flue gas distribution plate A7 and the flue gas distribution plate B8 are uniformly distributed with small holes 11 with a diameter of 120 mm at positions other than the 16 positions coinciding with the spray gun 9.

[0028] In the working process, the flue gas distribution plate A7 and the flue gas distribution plate B8 are arranged in the conical region of the upper section 2 of the spray drying tower body 1 to rectify the tangential high-temperature flue gas into vertical downward flow, thereby avoiding the concentration of flue gas near the wall surface to cause heat loss; the number of the large holes 10 on the flue gas distribution plate A7 and the flue gas distribution plate B8 is the same as the number of the spray gun 9, and the opening position of the large hole 10 is determined by the spray gun 9, that is, the center of the opening coincides with the axis of the spray gun 9, and the opening area of the large hole 10 is slightly larger than the maximum area of the circle formed by the droplets sprayed by the spray gun 9, so that the high-temperature flue gas will be concentrated in the area near the nozzle after passing through the flue gas distribution plate, to ensure that the cold slurry can rapidly exchange heat with the high-temperature flue gas after being sprayed; the spray gun 9 is arranged vertically downward to eliminate the adverse effects of the cross arrangement of the spray heads on the product particle size;

[0029] Specific research method: under simulated conditions, the physical model is drawn by using Solidworks software according to the size of each component of the spray drying tower body 1 and the flue gas distribution plate A7, the flue gas distribution plate B8 and the spray gun 9, then the mesh is divided by using ICEM software, and the mesh of the spray gun 9 and the flue gas distribution plate A7 and the flue gas distribution plate B8 with smaller size is encrypted to ensure the accuracy of numerical simulation; appropriate material physical parameters are set through literature research, and operating parameters that can meet the industrial demand are selected; the drying rate and particle size distribution under theoretical conditions are obtained through numerical simulation.

Claims

1. A spray drying apparatus for intensifying interphase heat transfer, comprising a spray drying tower body (1); characterized in that: It also includes the upper section of the tower body (2), the middle section of the tower body (3), the lower section of the tower body (4), the gas inlet (5), the gas outlet (6), the flue gas distribution plate A (7), the flue gas distribution plate B (8), the spray gun (9); the spray drying tower body (1) includes the upper section of the tower body (2), the middle section of the tower body (3) and the lower section of the tower body (4); the upper section of the tower body (2) is welded with the conical structure on the upper end of the middle section of the tower body (3); the lower section of the tower body (4) is welded with the conical structure on the lower end of the middle section of the tower body (3); the middle section of the tower body (3) adopts the cylindrical structure; the gas inlet (5) is fixedly connected with the cylindrical structure on the outer side of the sidewall of the upper section of the tower body (2); the gas outlet (6) is fixedly connected with the 90° elbow pipe on the lower end of the outlet of the lower section of the tower body (4); the flue gas distribution plate A (7) and the flue gas distribution plate B (8) are respectively installed on the inner side of the upper section of the tower body (2); the flue gas distribution plate A (7) is located on the upper end of the flue gas distribution plate B (8); the flue gas distribution plate A (7) and the flue gas distribution plate B (8) have the same opening rate and the installation position is lower than the gas inlet (5); the spray gun (9) is installed on the inner side of the upper section of the tower body (2); the spray gun (9) penetrates the flue gas distribution plate A (7) and the flue gas distribution plate B (8).

2. The intensified interphase heat transfer spray drying apparatus of claim 1, wherein: The diameter of the gas inlet (5) is 1300mm; the diameter of the gas outlet (6) is 1800mm; the gas inlet (5) and the gas outlet (6) form a 90° angle.

3. The intensified interphase heat transfer spray drying apparatus of claim 1, wherein: The spray gun (9) is vertically arranged; the number of the spray gun (9) is 8; the spray gun (9) is arranged on the circumference with a distance of 3500mm from the center; the spray gun (9) is annularly and equidistantly distributed; the diameter of the spray gun (9) is 150mm; the spray gun (9) adopts the pressure type nozzle; the spray gun (9) extends into the tower by 300mm.

4. The intensified interphase heat transfer spray drying apparatus of claim 1, wherein: The thickness of the flue gas distribution plate A (7) and the flue gas distribution plate B (8) is 200mm; the distance between the flue gas distribution plate A (7) and the flue gas distribution plate B (8) is 1000mm.

5. The intensified interphase heat transfer spray drying apparatus of claim 1, wherein: The outer surface of the flue gas distribution plate A (7) and the flue gas distribution plate B (8) is provided with a large hole (10); the number of the large hole (10) of the flue gas distribution plate A (7) and the flue gas distribution plate B (8) is the same as that of the spray gun (9); the position of the large hole (10) of the flue gas distribution plate A (7) and the flue gas distribution plate B (8) coincides with the center position of the spray gun (9).

6. The intensified interphase heat transfer spray drying apparatus of claim 1, wherein: The diameter of the flue gas distribution plate A (7) is 9345mm; the diameter of the large hole (10) of the flue gas distribution plate A (7) is 1500mm; the diameter of the flue gas distribution plate B (8) is 10500mm; the diameter of the large hole (10) of the flue gas distribution plate B (8) is 1688mm.

7. The intensified interphase heat transfer spray drying apparatus of claim 1, wherein: The flue gas distribution plate A (7) and the flue gas distribution plate B (8) are uniformly provided with small holes (11) with a diameter of 120mm at positions other than the 16 large holes (10) coinciding with the positions of the spray gun (9).

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