Heating system of spray drying tower
By introducing a heat recovery heat exchanger into the heating system of the spray drying tower, the heat of steam condensate and part of the steam is recovered and used to preheat fresh air, solving the problem of low steam utilization and achieving improved fresh air temperature and energy savings.
Patent Information
- Application Number
- CN202423047386.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-10
- Publication Date
- 2025-10-31
- Estimated Expiration
- 2034-12-10
AI Technical Summary
In the existing heating system of spray drying towers, the steam utilization rate is low and the heat exchange is insufficient, resulting in the waste of condensate and some steam heat, and the energy utilization rate is not high.
A heat recovery heat exchanger is introduced into the heating system of the spray drying tower. Through heat exchange between the steam heat exchanger and the heat recovery heat exchanger, the heat of the steam condensate and part of the steam is recovered and used to preheat the fresh air, increase the fresh air temperature, and further heat the air to the required temperature in combination with an electric heater.
It increases the fresh air temperature by 10-20℃, saves 10-15% of steam energy consumption, improves steam utilization, and reduces energy waste.
Smart Images
Figure CN223490434U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the technical field of air handling equipment, and relates to a heating system for a spray drying tower. Background Technology
[0002] Spray drying is a technique that atomizes and sprays solutions, emulsions, or suspensions, allowing them to come into contact with hot air, thereby drying the droplets into powder. Due to its relatively low drying temperature and the resulting more uniform powder particle size, it is commonly used in the pharmaceutical and chemical production fields for drying heat-sensitive materials. Since liquid materials contain a large amount of water, evaporating this water inevitably consumes a significant amount of heat; therefore, the heating system of the spray drying tower is crucial.
[0003] To make more efficient use of energy, some spray drying towers have begun to use a hybrid heating system. This system consists of steam heating and electric heating. Steam is primarily used to heat the fresh air to 140-150℃, and then electric heating is used to raise the temperature to 180-200℃. The steam heating system typically heats the fresh air through a steam heat exchanger. The steam, after heat exchange, passes through a heat exchanger and a steam trap before being discharged to a hot water tank (condensate + some steam). Its drawbacks are: low steam utilization rate, insufficient heat exchange, and the discharged condensate + some steam still retaining significant heat, resulting in waste. Utility Model Content
[0004] This invention addresses the shortcomings of existing technologies by providing a heating system for a spray drying tower that can recover steam heat, improve energy utilization, and reduce waste.
[0005] To solve the above-mentioned technical problems, the objective of this utility model is achieved through the following technical solution:
[0006] A heating system for a spray drying tower includes a steam heating system and an electric heating system. The steam heating system includes a fresh air delivery channel, a steam delivery channel, a blower, a steam heat exchanger, and a heat recovery heat exchanger. The fresh air delivery channel is sequentially connected to the fresh air heat exchange chamber of the heat recovery heat exchanger, the blower, and the air heat exchange chamber of the steam heat exchanger. The steam delivery channel is sequentially connected to the steam heat exchange chamber of the steam heat exchanger and the recovery heat exchange chamber of the heat recovery heat exchanger. The fresh air heat exchange chamber of the heat recovery heat exchanger exchanges heat with the recovery heat exchange chamber to heat the flowing fresh air in the fresh air heat exchange chamber. The air heat exchange chamber of the steam heat exchanger exchanges heat with the steam heat exchange chamber to heat the flowing air in the air heat exchange chamber.
[0007] In the heating system of the spray drying tower described above, the heat recovery heat exchanger is a steam-type finned tube heat exchanger.
[0008] In the heating system of the spray drying tower described above, the heat recovery heat exchanger includes a shell, inside which heat exchange tubes and fins are arranged. A heat recovery heat exchange chamber is formed inside the heat exchange tubes, and a fresh air heat exchange chamber is formed outside the heat exchange tubes. One end of the shell is provided with a steam inlet and a steam outlet, and the other end is connected to the heat exchange tubes via an elbow. One side of the shell is provided with a fresh air inlet connected to the outside or a fresh air device, and the other side is provided with a fresh air outlet connected to the inlet end of a blower. Preferably, the heat exchange tubes are arranged in parallel, and the elbow is integrally formed with the heat exchange tubes, with a bending angle of 180°.
[0009] In the heating system of the spray drying tower described above, a steam trap is provided at the outlet end of the steam heat exchange chamber of the steam heat exchanger, and a mixture of steam and condensate is transported through the steam transport channel between the steam heat exchanger and the heat recovery heat exchanger.
[0010] In the heating system of the spray drying tower described above, the inlet end of the steam heat exchanger's steam heat exchange chamber is connected to a steam generator, and the outlet end of the heat recovery heat exchanger's heat recovery chamber is connected to a hot water tank; furthermore, the water in the hot water tank can be circulated back to the steam generator to save water resources.
[0011] In the heating system of the spray drying tower described above, the outlet end of the air heat exchange chamber of the steam heat exchanger is connected to an electric heating channel, an electric heater is installed on the electric heating channel, and the electric heating channel is connected to the air inlet of the spray drying tower; the electric heater adopts a type of heater commonly used in the art.
[0012] In the heating system of the spray drying tower described above, an air inlet and a feed inlet are respectively provided on both sides of the top of the spray drying tower. The feed inlet is connected to a storage device through a feed channel. The bottom of the spray drying tower is provided with a discharge outlet, which is connected to a discharge channel.
[0013] In the heating system of the spray drying tower described above, an exhaust port is provided above the discharge port. The exhaust port is connected in sequence to a primary separator, a secondary separator, and a tail gas emission device through an exhaust channel. The bottoms of the primary separator and the secondary separator are respectively connected to the discharge channel. The primary separator and the secondary separator adopt commonly used types of separators in the art, such as a cyclone separator and a bag filter in sequence.
[0014] Compared with the prior art, this utility model has the following advantages:
[0015] This invention provides a heating system for a spray drying tower. A heat recovery heat exchanger is installed in the fresh air section before the steam heat exchanger. The condensate and some steam discharged from the steam heat exchanger are introduced into the heat recovery heat exchanger to preheat the fresh air, increasing its temperature and improving steam utilization. The heating system for the spray drying tower provided by this invention can increase the fresh air temperature by 10-20℃ and save 10-15% of steam energy consumption. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the present invention;
[0017] Figure 2 This is a schematic diagram of the structure of the heat recovery heat exchanger of this utility model;
[0018] Reference numerals: 1. Fresh air conveying channel; 2. Steam conveying channel; 3. Blower; 4. Steam heat exchanger; 5. Heat recovery heat exchanger; 6. Shell; 7. Heat exchange tube; 8. Fin; 9. Steam inlet; 10. Steam outlet; 11. Elbow; 12. Electric heating channel; 13. Electric heater; 14. Spray drying tower; 15. Feeding channel; 16. Storage device; 17. Discharge channel; 18. Exhaust channel; 19. Primary separator; 20. Secondary separator; 21. Tail gas emission device. Detailed Implementation
[0019] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. See also: Figure 1-2 :
[0020] A heating system for a spray drying tower includes a steam heating system and an electric heating system. The steam heating system includes a fresh air delivery channel 1, a steam delivery channel 2, a blower 3, a steam heat exchanger 4, and a heat recovery heat exchanger 5. The fresh air delivery channel 1 is sequentially connected to the fresh air heat exchange chamber of the heat recovery heat exchanger 5, the blower 3, and the air heat exchange chamber of the steam heat exchanger 4. The steam delivery channel 2 is sequentially connected to the steam heat exchange chamber of the steam heat exchanger 4 and the heat recovery heat exchange chamber of the heat recovery heat exchanger 5. The fresh air heat exchange chamber of the heat exchanger 5 exchanges heat with the recovery heat exchange chamber to heat the flowing fresh air in the fresh air heat exchange chamber, and the air heat exchange chamber of the steam heat exchanger 4 exchanges heat with the steam heat exchange chamber to heat the flowing air in the air heat exchange chamber; the electric heating system includes: the outlet end of the air heat exchange chamber of the steam heat exchanger 4 is connected to the electric heating channel 12, the electric heating channel 12 is provided with an electric heater 13, and the electric heating channel 12 is connected to the air inlet of the spray drying tower 14; the electric heater 13 adopts a heater of a type commonly used in the art.
[0021] Comparison Appendix Figure 1The heating process of the heating system in this embodiment is as follows: Driven by the blower 3, fresh air is transported along the fresh air conveying channel 1. The fresh air enters the heating system through the fresh air heat exchange chamber of the heat recovery heat exchanger 5. After exchanging heat with the steam (condensate) in the heat recovery heat exchange chamber, the fresh air in the heat exchange chamber is heated up. The air heated to 10-20°C enters the air heat exchange chamber of the steam heat exchanger 4. The air in the air heat exchange chamber exchanges heat with the steam in the steam heat exchange chamber, and is heated to 140-150°C. Then it enters the electric heating system, where the electric heater 13 further heats the air to 180°C. -200℃ and delivered to the air inlet of spray drying tower 14; the steam for heating is delivered along steam delivery channel 2 and enters the heating system through the steam heat exchange chamber of steam heat exchanger 4. The steam in the steam heat exchange chamber exchanges heat with the air in the air heat exchange chamber. The cooled steam (condensate) is discharged from the steam heat exchanger 4 through the outlet end of the steam heat exchange chamber and continues to be delivered along steam delivery channel 2 to the heat recovery heat exchanger 5. The steam (condensate) in the heat recovery heat exchanger 5 exchanges heat with the fresh air in the fresh air heat exchanger 5. After the heat is used up, it is discharged from the heat recovery heat exchanger 5.
[0022] Comparison Appendix Figure 2 In this embodiment, the heat recovery heat exchanger 5 is a steam-type finned 8-tube heat exchanger. Specifically, the heat recovery heat exchanger 5 includes a shell 6, in which heat exchange tubes 7 and fins 8 are disposed. A heat recovery heat exchange chamber is formed inside the heat exchange tubes 7, and a fresh air heat exchange chamber is formed outside the heat exchange tubes 7. One end of the shell 6 is provided with a steam inlet 9 and a steam outlet 10, and the other end is connected to the heat exchange tubes 7 through an elbow 11. One side of the shell 6 is provided with a fresh air inlet connected to the outside or a fresh air device, and the other side is provided with a fresh air outlet connected to the inlet end of the blower 3. Preferably, the heat exchange tubes 7 are arranged in parallel, and the elbow 11 is integrally formed with the heat exchange tubes 7, with a bending angle of 180°.
[0023] Furthermore, a steam trap is provided at the outlet end of the steam heat exchange chamber of the steam heat exchanger 4, and a mixture of steam and condensate is transported through the steam transport channel 2 between the steam heat exchanger 4 and the heat recovery heat exchanger 5.
[0024] Furthermore, the inlet end of the steam heat exchanger 4 is connected to a steam generator, and the outlet end of the heat recovery heat exchanger 5 is connected to a hot water tank; furthermore, the water in the hot water tank can be circulated to the steam generator to save water resources.
[0025] The spray drying tower 14 of this embodiment further includes: an air inlet and a feed inlet respectively provided on both sides of the top of the spray drying tower 14; the feed inlet is connected to the storage device 16 through the feed channel 15; and the bottom of the spray drying tower 14 is provided with a discharge outlet connected to the discharge channel 17. The material in the storage device 16 enters the tower through the feed channel 15 and the feed inlet, and hot air enters the tower through the electric heating channel 12 and the air inlet. After the hot air comes into contact with the material, it dries it into powder and is discharged from the discharge outlet at the bottom of the tower. The gas enters the exhaust port, and the material enters the discharge channel 17.
[0026] In the heating system of the spray drying tower 14 described above, an exhaust port is provided above the discharge port. The exhaust port is connected in sequence to a primary separator 19, a secondary separator 20, and a tail gas emission device 21 through an exhaust channel 18. The bottoms of the primary separator 19 and the secondary separator 20 are respectively connected to the discharge channel 17. The primary separator 19 and the secondary separator 20 adopt commonly used types of separators in the art, such as a cyclone separator and a bag filter in sequence. The primary separator 19 and the secondary separator 20 sequentially separate the material powder in the tail gas and transport it to the discharge channel 17. The collected material powder is simultaneously collected in a collection device, and the separated tail gas enters the tail gas emission device 21 for treatment and is then discharged.
[0027] The above embodiments are merely preferred embodiments of the present utility model and are not intended to limit the scope of protection of the present utility model. Therefore, all equivalent changes made to the structure, shape, and principle of the present utility model should be covered within the scope of protection of the present utility model.
Claims
1. A heating system for a spray drying tower, the heating system comprising a steam heating system and an electric heating system, characterized in that, The steam heating system includes a fresh air delivery channel (1), a steam delivery channel (2), a blower (3), a steam heat exchanger (4), and a heat recovery heat exchanger (5). The fresh air delivery channel (1) is connected in sequence to the fresh air heat exchange chamber of the heat recovery heat exchanger (5), the blower (3), and the air heat exchange chamber of the steam heat exchanger (4). The steam delivery channel (2) is connected in sequence to the steam heat exchange chamber of the steam heat exchanger (4) and the heat recovery heat exchange chamber of the heat recovery heat exchanger (5). The fresh air heat exchange chamber of the heat recovery heat exchanger (5) and the heat recovery heat exchange chamber form a heat exchange to heat the flowing fresh air in the fresh air heat exchange chamber. The air heat exchange chamber of the steam heat exchanger (4) and the steam heat exchange chamber form a heat exchange to heat the flowing air in the air heat exchange chamber.
2. The heating system for a spray drying tower according to claim 1, characterized in that, The heat recovery heat exchanger (5) is a steam-type finned tube heat exchanger.
3. The heating system for a spray drying tower according to claim 2, characterized in that, The heat recovery heat exchanger (5) includes a shell (6), in which heat exchange tubes (7) and fins (8) are provided. A heat recovery heat exchange chamber is formed inside the heat exchange tubes (7), and a fresh air heat exchange chamber is formed outside the heat exchange tubes (7). One end of the shell (6) is provided with a steam inlet (9) and a steam outlet (10), and the other end is connected to the heat exchange tubes (7) through an elbow (11). One side of the shell (6) is provided with a fresh air inlet connected to the outside or a fresh air device, and the other side is provided with a fresh air outlet connected to the inlet end of the blower (3).
4. The heating system for a spray drying tower according to claim 2, characterized in that, A steam trap is provided at the outlet end of the steam heat exchange chamber of the steam heat exchanger (4), and the steam transport channel (2) between the steam heat exchanger (4) and the heat recovery heat exchanger (5) transports a mixture of steam and condensate.
5. The heating system for a spray drying tower according to claim 3, characterized in that, The inlet end of the steam heat exchanger (4) is connected to a steam generator, and the outlet end of the heat recovery heat exchanger (5) is connected to a hot water tank.
6. The heating system for a spray drying tower according to claim 1, characterized in that, The outlet end of the air heat exchange chamber of the steam heat exchanger (4) is connected to the electric heating channel (12), and an electric heater (13) is provided on the electric heating channel (12). The electric heating channel (12) is connected to the air inlet of the spray drying tower (14).
7. The heating system for a spray drying tower according to claim 6, characterized in that, The spray drying tower (14) has an air inlet and a feed inlet on its top two sides respectively. The feed inlet is connected to the storage device (16) through the feed channel (15). The spray drying tower (14) has a discharge outlet at its bottom, which is connected to the discharge channel (17).
8. The heating system for a spray drying tower according to claim 7, characterized in that, An exhaust port is provided above the discharge port. The exhaust port is connected in sequence to the primary separator (19), the secondary separator (20) and the exhaust gas emission device (21) through the exhaust channel (18). The bottoms of the primary separator (19) and the secondary separator (20) are respectively connected to the discharge channel (17).