Drying device for citric acid and salt thereof

Abstract

The utility model belongs to the field of production equipment of citric acid and salt thereof, and particularly relates to a drying device of citric acid and salt thereof, which comprises a drying machine, an annular disc and a main shaft are arranged in the drying machine, and the main shaft is respectively connected with a motor and a compressed air system and is connected with a split shaft which is provided with a scraper blade and a nozzle. The nozzles are communicated with a compressed air system through cavities in the split shaft and the main shaft; annular discs are arranged in the drying machine, split shafts are arranged above the annular discs, the scraping plates make contact with the annular discs, and the split shafts are arranged below the annular disc on the bottommost layer. A material inlet, a tail gas outlet and a discharge hole are formed in the dryer; and in the vertical direction, the upper and lower adjacent annular discs are overlapped. According to the device, citric acid and salt thereof can be fully heated at high temperature layer by layer, hard friction between the scraping plate and the disc body is avoided, and paste materials, black materials and the like caused by over-high local heating of materials are avoided through fluidized air, so that high-quality production of ultralow-moisture citric acid and salt thereof is realized.

Description

Technical Field

[0001] The utility model belongs to the field of production equipment of citric acid and its salt, and specifically relates to a drying device for citric acid and its salt. Background Art

[0002] In the production process of citric acid and its salts, some products with very low moisture requirements and very high product quality requirements are often involved. Existing drying equipment may not be able to increase the temperature due to its own limitations, or may be prone to equipment wear and foreign matter introduction due to defects in the material transportation process, making it difficult to produce ultra-low moisture, high-quality citric acid and its salts without impurities. Utility Model Content

[0003] In order to solve the existing technical problems, the utility model provides a drying device for citric acid and its salts, by which ultra-low moisture products can be prepared, the crystal water in the crystals can be dried out, and anhydrous citric acid and anhydrous citric acid derivatives with ultra-low moisture can be produced; and the continuity and airtightness of the production process are ensured, foreign matter and foreign matter caused by the wear of the equipment itself are prevented from mixing into the materials, and the products are ensured to be high-purity, foreign matter-free fine citric acid and citrate products.

[0004] The technical solution of the utility model is as follows:

[0005] A drying device for citric acid and its salts comprises a dryer, wherein an annular disk and a main shaft are arranged in the dryer, one end of the main shaft passes through the top of the dryer to be connected to a motor, and the other end passes through the bottom of the dryer to be connected to a compressed air system, the main shaft arranged in the middle of the dryer is connected to a sub-shaft, a scraper and a nozzle are arranged on the sub-shaft, and the nozzle is connected to the compressed air system through a cavity in the sub-shaft and a cavity on the main shaft; an annular disk is arranged in the dryer, and a sub-shaft is arranged above the annular disk, the annular disk is divided into an annular heating disk and an annular cooling disk, the annular heating disk is arranged above the annular cooling disk, the scraper contacts the annular disk, and the sub-shaft is arranged below the annular disk at the bottom layer; a material inlet and an exhaust gas outlet are arranged at the top of the dryer, and a material discharge port is arranged at the bottom; in the vertical direction, adjacent annular disks are partially overlapped.

[0006] Preferably, the exhaust gas outlet is connected to a dust removal system.

[0007] Preferably, an automatic compressed air drain valve is provided on the pipeline connecting the compressed air system to the main shaft.

[0008] Preferably, a baffle plate is provided on the inner edge or the outer edge of the annular disk, and the baffle plates on the edges of adjacent annular disks are provided on different inner and outer edges, such as a baffle plate is provided on the outer edge of the first layer of annular disk, and a baffle plate is provided on the inner edge of the second layer of annular disk; the distance between the baffle plate provided on the inner edge and the main axis is smaller than the distance between the inner edge of the annular disk on which the baffle plate is provided on the outer edge and the main axis, and the distance between the baffle plate provided on the outer edge and the main axis is greater than the distance between the outer edge of the annular disk on which the baffle plate is provided on the inner edge and the main axis.

[0009] Preferably, an inner scraper is arranged above the annular disk with a baffle plate at the outer edge, an outer scraper is arranged above the annular disk with a baffle plate at the inner edge, and the first layer of scrapers above the bottom of the dryer is an outer scraper.

[0010] Preferably, a material baffle is provided on the outer edge of the annular disk arranged at the bottom layer in the dryer.

[0011] Preferably, a cavity is provided in the annular disk, the cavity in the annular heating disk is connected to a hot water source through a fixed pipe A1, and the cavity in the annular cooling disk is connected to a cold water source through a fixed pipe B1. Further preferably, the cavity in the annular heating disk is connected to a hot water collection device through a fixed pipe A2, and the cavity in the annular cooling disk is connected to a cold water collection device through a fixed pipe B2. More preferably, the fixed pipe A1 and the fixed pipe A2 are respectively provided on both sides of the annular heating disk, and the fixed pipe B1 and the fixed pipe B2 are respectively provided on both sides of the annular cooling disk.

[0012] Preferably, the main shaft and the bottom of the dryer are mechanically sealed, and a fan is provided on the discharge port.

[0013] Preferably, the air compression system comprises a compressed air source, a dehumidification device, a heating device, a pressure reducing device and a valve which are connected in sequence.

[0014] In the utility model, the semi-finished citric acid and its salt with high moisture content are input into the annular heating plate of the highest layer of the dryer through the material inlet through the continuous production and feeding of the previous process, and are scraped by the scraper to form a uniform material layer, and are transported to the annular plates of the lower layers circle by circle; by adjusting the temperature of hot water and compressed air, it is ensured that the product can be dried within a specific moisture content range, and in the drying process, compressed air is sprayed through the nozzle to make the material separate from the annular plate, so as to prevent the annular plate from being locally heated for a long time to form yellow material, black material or paste, and the flowing air takes away the dried moisture, enters the dust removal system through the tail gas outlet, and is discharged after being treated, thereby enhancing the drying effect; after the dried material passes through the annular heating plates layer by layer, it reaches the corresponding moisture content range, and the medium introduced into the annular cooling plate of the lower layer is cold water, and the high-temperature material is cooled to obtain a normal temperature product, so that it finally enters the next process through the discharge port and the pipe fan.

[0015] The utility model provides a drying device for citric acid and its salts, through which anhydrous citric acid and anhydrous citrate with ultra-low moisture content are produced; the continuity and airtightness of the production process are ensured, foreign matter and foreign matter caused by the wear of the equipment itself are prevented from mixing into the material, and the product is ensured to be a high-purity, foreign-matter-free fine citric acid and citrate product. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the structure of the utility model;

[0017] Figure 2 This is a schematic diagram of the inner scraper of the utility model;

[0018] Figure 3 This is a practical diagram of the outward-direction scraper of the utility model;

[0019] In the figure, 1 is a dryer, 2 is a main shaft, 3 is a branch shaft, 4 is a cold water collecting device, 5 is a discharge port, 6 is a compressed air automatic drain valve, 7 is a pressure reducing device, 8 is a heating device, 9 is a dehumidification device, 10 is a compressed air source, 11 is a cold water source, 12 is a hot water source, 13 is a baffle plate, 14 is an annular disk, 15 is an exhaust gas outlet, 16 is a dust removal system, 17 is a motor, 18 is a material inlet, 19 is a nozzle, 20 is a scraper, 21 is a hot water collecting device, and 22 is a fan off. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0021] As shown in the figure, a drying device for citric acid and its salts includes a dryer 1, in which an annular disk 14 and a main shaft 2 are arranged, one end of the main shaft 2 passes through the top of the dryer 1 to connect to the motor 17, and the other end passes through the bottom of the dryer 1 to connect to the compressed air system, and the main shaft 2 arranged in the middle of the dryer 1 is connected to the sub-shaft 3, and the sub-shaft 3 is provided with a scraper 20 and a nozzle 19, and the nozzle 19 is connected to the compressed air system through the cavity in the sub-shaft 3 and the cavity on the main shaft 2; an annular disk 14 is arranged in the dryer 1 4, a sub-axis 3 is arranged above the annular disk 14, the annular disk 14 is divided into an annular heating disk 14-1 and an annular cooling disk 14-2, the annular heating disk 14-1 is arranged above the annular cooling disk 14-2, the scraper 20 is in contact with the annular disk 14, and the sub-axis 3 is arranged below the bottom annular disk 14; a material inlet 18 and an exhaust gas outlet 15 are arranged on the top of the dryer 1, the exhaust gas outlet 15 is connected to the dust removal system 16, and a discharge port 5 is arranged at the bottom; in the vertical direction, adjacent annular disks 14 are partially overlapped.

[0022] Preferably, there is soft contact between the scraper 20 and the annular disk 14 , and a soft material such as silica gel is provided at the bottom of the scraper 20 .

[0023] In another embodiment, a compressed air automatic drain valve 6 is provided on the pipeline of the compressed air system connected to the main shaft 2, and liquid impurities that may exist or have not been completely removed in the compressed air during operation are discharged through the compressed air automatic drain valve 6. The air compression system includes a compressed air source 10, a dehumidifier 9, a heating device 8, a pressure reducing device 7 and a valve connected in sequence. The compressed air passes through the dehumidifier 9 and the heating device 8, and can provide compressed air with a temperature equivalent to that inside the dryer 1. The compressed air pressure is reduced to a pressure that can just blow the material on the annular disk 14 off the disk surface through the pressure reducing device 7, thereby preventing the material from being attached to the annular disk 14 for a long time and melting due to heat to form paste or black material, and preventing it from being mixed into the product, which affects the purity and leads to quality degradation.

[0024] In another embodiment, a baffle plate 13 is provided on the inner edge or outer edge of the annular disk 14, and the baffle plates 13 on the edges of adjacent annular disks 14 are provided on different inner and outer edges, such as a baffle plate 13 is provided on the outer edge of the first layer of annular disks 14 from top to bottom, and a baffle plate 13 is provided on the inner edge of the second layer of annular disks 14; the distance between the baffle plate 13 provided on the inner edge and the main shaft 2 is smaller than the distance between the inner edge of the annular disk 14 on which the baffle plate 13 is provided on the outer edge and the main shaft 2, and the distance between the baffle plate 13 provided on the outer edge and the main shaft 2 is greater than the distance between the outer edge of the annular disk 14 on which the baffle plate 13 is provided on the inner edge and the main shaft 2, and there is a gap between the baffle plate 13 and the side wall of the dryer 1 and the main shaft 2; an inner direction scraper 20 (such as Figure 2 As shown), an outer scraper 20 is arranged above the annular disk 14 with a baffle plate 13 arranged on the inner edge (as shown Figure 3 As shown in the figure, the first scraper 20 above the bottom of the dryer 1 is an outer scraper 20; the annular disk 14 arranged at the bottom of the dryer 1 is provided with a baffle plate 13 at the outer edge, and the baffle plate 13 can prevent the material from falling onto the annular disk 14 and falling directly to the bottom of the dryer 1; the inner scraper 20 makes the material finally fall from the outer edge of the annular disk 14.

[0025] In another embodiment, a cavity is provided in the annular disk 14, the cavity in the annular heating disk 14-1 is connected to the hot water source 12 via a fixed pipe A1, and the cavity in the annular cooling disk 14-2 is connected to the cold water source 11 via a fixed pipe B1; the cavity in the annular heating disk 14-1 is connected to the hot water collecting device 21 via a fixed pipe A2, and the cavity in the annular cooling disk 14-2 is connected to the cold water collecting device 4 via a fixed pipe B2. More preferably, the fixed pipe A1 and the fixed pipe A2 are respectively arranged on both sides of the annular heating plate 14-1, and the fixed pipe B1 and the fixed pipe B2 are respectively arranged on both sides of the annular cooling plate 14-2. The fixed pipes A1 and A2 respectively pass through the side wall of the dryer 1 to connect with the hot water source and the hot water collecting device 21, and the fixed pipes A1 and A2 are fixedly connected to the side wall of the dryer 1, which not only play the role of allowing hot water to flow into and out of the annular heating plate 14-1, but also play the purpose of fixing the annular heating plate 14-1; the fixed pipes B1 and B2 respectively pass through the side wall of the dryer 1 to connect with the cold water source L and the cold water source collecting device, and the fixed pipes B1 and B2 are fixedly connected to the side wall of the dryer 1, which not only play the role of allowing hot water to flow into and out of the annular heating plate 14-1, but also play the purpose of fixing the annular heating plate 14-1.

[0026] In another embodiment, the main shaft 2 and the bottom of the dryer 1 are mechanically sealed, the discharge port 5 is connected to the fan 22, four supporting legs are evenly arranged at the bottom of the dryer 1, and the outer edge of the annular disk 14 is connected to the inner wall of the dryer 1 through a steel pipe.

[0027] In another embodiment, the scraper 20 is movably connected to the sub-shaft 3, a clip is provided on the scraper 20, a groove is provided on the sub-shaft 3, the scraper 20 is clip-connected to the sub-shaft 3, and the height of the scraper 20 can be adjusted to prevent the surface of the annular disk 14 from being uneven. The scraper 20 can also be fixedly connected to the sub-shaft 3 by welding, bonding or integral molding.

[0028] In the utility model, the semi-finished citric acid and its salt with high moisture content are input into the annular heating plate 14-1 at the highest layer of the dryer 1 through continuous production and feeding in the previous process, and the main shaft 2 is driven by the motor 17, and the main shaft 2 drives the sub-shaft 3, so that the scraper 20 scrapes to form a uniform material layer, and conveys it to the annular plate 14 at the lower layer in a circle; by adjusting the temperature of hot water and compressed air, it is ensured that the product can be dried within a specific moisture content range. In the drying process, the compressed air is ejected through the nozzle 19 to make the material separate from the annular plate 14, so as to prevent the annular plate 14 from being localized. The dried material is heated for a long time to form yellow material, black material or paste, and the flowing air takes away the dried moisture, enters the dust removal system 16 through the exhaust outlet 15, and is discharged after treatment, which enhances the drying effect; the dried material reaches the corresponding moisture content range after passing through the annular heating plate 14-1 layer by layer, and the medium passed into the annular cooling plate 14-2 of the lower layer is cold water, which cools the high-temperature material to obtain a normal temperature product, which finally falls into the bottom of the dryer 1, and uses the outward scraper 20 to make the product finally pass through the discharge port 5 and enter the next process through the fan 22.

[0029] At present, conventional equipment cannot produce the ultra-low moisture products required by citric acid and its salts. The heating equipment conveyed by conventional scrapers 20 is very easy to wear and introduce impurities such as iron filings into the product group, affecting the product quality. The utility model can fully heat citric acid and its salts layer by layer at high temperature through the optimization of the equipment, so as to obtain ultra-low moisture products, and avoid the hard friction between the scraper 20 and the disc body. At the same time, the material is blown up by compressed air to prevent the local overheating of the material to produce paste, black material, etc., so as to achieve high-quality production of ultra-low moisture citric acid and its salts.

[0030] The utility model provides a drying device for citric acid and its salts, through which free water in the product and crystal water in the crystals can be dried out to produce anhydrous citric acid and anhydrous citrate with ultra-low moisture content; and the continuity and airtightness of the production process are ensured to avoid foreign matter and foreign matter caused by the wear of the equipment itself from mixing into the material, thereby ensuring that the product is a high-purity, foreign-matter-free fine citric acid and citrate product.

Claims

1. A drying device for citric acid and its salts, comprising a drying machine (1), characterized in that: The dryer (1) is provided with an annular disk (14) and a main shaft (2); one end of the main shaft (2) passes through the top of the dryer (1) to be connected to a motor (17); the other end passes through the bottom of the dryer (1) to be connected to a compressed air system; the main shaft (2) arranged in the middle of the dryer (1) is connected to a sub-shaft (3); a scraper (20) and a nozzle (19) are arranged on the sub-shaft (3); the nozzle (19) is connected to the compressed air system through a cavity in the sub-shaft (3) and a cavity on the main shaft (2); A sub-axis (3) is arranged on the top, and the annular disk (14) is divided into an annular heating disk (14-1) and an annular cooling disk (14-2). The annular heating disk (14-1) is arranged above the annular cooling disk (14-2). The scraper (20) is in contact with the annular disk (14). The sub-axis (3) is arranged below the bottom annular disk (14). The top of the dryer (1) is provided with a material inlet (18) and an exhaust gas outlet (15), and the bottom is provided with a discharge port (5). In the vertical direction, adjacent annular disks (14) partially overlap.

2. A drying device for citric acid and its salts according to claim 1, characterized in that: A compressed air automatic drain valve (6) is provided on the pipeline of the compressed air system connected to the main shaft (2).

3. A drying device for citric acid and its salts according to claim 1, characterized in that: A material baffle plate (13) is arranged on the inner edge or the outer edge of the annular disk (14); the material baffle plates (13) on the edges of adjacent annular disks (14) are arranged on different inner and outer edges; the distance between the material baffle plate (13) arranged on the inner edge and the main shaft (2) is smaller than the distance between the inner edge of the annular disk (14) having the material baffle plate (13) arranged on the outer edge and the main shaft (2); and the distance between the material baffle plate (13) arranged on the outer edge and the main shaft (2) is larger than the distance between the outer edge of the annular disk (14) having the material baffle plate (13) arranged on the inner edge and the main shaft (2).

4. A drying device for citric acid and its salts according to claim 3, characterized in that: An inner scraper (20) is arranged above the annular disk (14) with a material baffle plate (13) arranged on the outer edge, and an outer scraper (20) is arranged above the annular disk (14) with a material baffle plate (13) arranged on the inner edge. The first layer of scrapers (20) above the bottom of the dryer (1) is an outer scraper (20).

5. A drying device for citric acid and its salts according to claim 4, characterized in that: A material blocking plate (13) is provided on the outer edge of the annular disk (14) arranged at the bottom layer in the drying machine (1).

6. The drying device for citric acid and its salts according to claim 1, characterized in that: A cavity is provided in the annular disk (14); the cavity in the annular heating disk (14-1) is connected to a hot water source (12) via a fixed pipe A1, and the cavity in the annular cooling disk (14-2) is connected to a cold water source (11) via a fixed pipe B1.

7. A drying device for citric acid and its salts according to claim 6, characterized in that: The cavity in the annular heating plate (14-1) is connected to the hot water collecting device (21) via a fixed pipe A2, and the cavity in the annular cooling plate (14-2) is connected to the cold water collecting device (4) via a fixed pipe B2.

8. The drying device for citric acid and its salts according to claim 7, characterized in that: The fixed pipe A1 and the fixed pipe A2 are respectively arranged on both sides of the annular heating plate (14-1), and the fixed pipe B1 and the fixed pipe B2 are respectively arranged on both sides of the annular cooling plate (14-2).

9. The drying device for citric acid and its salts according to claim 1, characterized in that: The main shaft (2) and the bottom of the dryer (1) are mechanically sealed, and a fan (22) is provided on the discharge port (5).

10. The drying device for citric acid and its salts according to claim 1, characterized in that: The air compression system comprises a compressed air source (10), a dehumidification device (9), a heating device (8), a pressure reducing device (7) and a valve which are connected in sequence.

Images