A printing and dyeing wastewater waste heat recovery unit
By treating dyeing and printing wastewater with a dual filtration system and a ceramic anti-corrosion coating, the corrosion problem of dyeing and printing wastewater on heat exchangers has been solved, extending the unit's lifespan and improving thermal energy utilization.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- ZIBO HANHUA THERMOELECTRIC EQUIP CO LTD
- Filing Date
- 2025-05-28
- Publication Date
- 2026-05-29
AI Technical Summary
Corrosive substances in dyeing and printing wastewater lead to short lifespan of heat exchangers and low thermal energy utilization, which are difficult to effectively solve with existing technologies.
The system employs a dual filtration system (pretreatment filtration and ultrasonic filtration) combined with a ceramic anti-corrosion coating to reduce the corrosiveness of wastewater. The filtration process is controlled by a conductivity sensor to improve filtration efficiency and extend the unit's lifespan.
It significantly reduces the corrosiveness of dyeing and printing wastewater, extends the service life of heat exchangers, and improves thermal energy utilization.
Smart Images
Figure CN224302867U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of wastewater waste heat recovery technology, and in particular to a waste heat recovery unit for dyeing and printing wastewater. Background Technology
[0002] The dyeing and printing industry is a traditional pillar industry, but it is also a high-energy-consuming, high-water-consuming, and high-polluting industry. The dyeing and printing process requires a large amount of hot water, generating a significant amount of high-temperature dyeing wastewater. Statistics show that a dyeing and printing plant generates 3-5 tons of wastewater for every 100 meters of fabric processed, and this wastewater carries a heat energy of 1.05 × 10⁻⁶ tons. 5 kJ / t, while the wastewater generated by the dyeing and printing process accounts for more than 70% of the wastewater in the textile industry, and the heat energy utilization rate is only about 35%, with a large amount of heat energy being wasted with the discharge of wastewater.
[0003] Dyeing and printing wastewater has a complex composition, containing dyes, sizing agents, auxiliaries, acids, alkalis, fiber impurities, inorganic salts, etc., which can cause corrosion and blockage of heat exchangers, affecting the lifespan and recovery efficiency of the unit. In response to this technical problem, this application proposes a waste heat recovery unit for dyeing and printing wastewater. Utility Model Content
[0004] The purpose of this utility model is to address the shortcomings of existing technologies by proposing a waste heat recovery unit for dyeing and printing wastewater, which aims to solve the problem of short service life of existing units.
[0005] To achieve the above objectives, the present invention provides the following technical solution:
[0006] A waste heat recovery unit for dyeing and printing wastewater includes a cold water tank. The cold water tank is connected to a second heat exchanger via a pipe, and an electromagnetic flow meter is installed on the pipe. The left front end of the second heat exchanger is connected to a first heat exchanger via a hot air pipe. The right rear end of the first heat exchanger is connected to the right front end of the second heat exchanger via a cold air pipe. A drain pipe is fixedly connected to the right side of the first heat exchanger. The right side of the second heat exchanger is connected to an energy storage tank via a pipe, and a pressure reducing valve is installed on the pipe. The left side of the first heat exchanger is connected to an ultrasonic filter via a pipe, and a water pump and a three-way valve are installed on the pipe. The left side of the ultrasonic filter is connected to a filter and the first heat exchanger via a pipe, and a three-way valve is installed on the pipe. A rotating component is installed inside the filter. The left side of the filter is connected to the wastewater tank via a pipe.
[0007] Furthermore, the rotating assembly includes a sliding frame, a rotating groove is provided on the rear side of the sliding frame, a filter screen frame is rotatably connected inside the rotating groove, a rotating baffle is fixedly connected to the front end of the inner wall of the sliding frame, a slot is provided on the rear side of the sliding frame, and a locking block is slidably connected inside the slot.
[0008] Furthermore, the filter has a filter port at the top, a drain port at the bottom, a water outlet at the bottom right side, and two cleaning ports at the front.
[0009] Furthermore, an energy storage outlet is provided on the rear side of the energy storage box, and an electromagnetic one-way valve is connected inside the energy storage outlet via a pipe.
[0010] Furthermore, support frames are fixedly connected to the left and right ends of the outer walls of heat exchanger one and heat exchanger two.
[0011] Furthermore, a wastewater outlet is provided at the bottom right side of the wastewater pool, and a cold water outlet is provided at the bottom right side of the cold water pool.
[0012] Furthermore, the sliding frame has a sliding groove inside, and a concave slider is slidably connected inside the sliding groove. A filter screen is installed inside the filter screen frame.
[0013] Furthermore, each of the pipes is equipped with a water pump, and the top front of the ultrasonic filter has a control slot, which contains a control panel.
[0014] This utility model has the following beneficial effects:
[0015] 1. In this utility model, when cleaning the filter, the locking block is removed and the filter screen frame is rotated to tilt it. The cleaning port and drain port are opened, and the filter screen and its inner wall are cleaned with a high-pressure water gun. The filtered material is discharged through the drain port. When replacing the filter screen, the filter screen frame is pulled out for replacement.
[0016] 2. In this utility model, the dual filtration of pretreatment filtration and ultrasonic filter significantly reduces the corrosiveness of wastewater. In addition, the ceramic anti-corrosion coating is sprayed inside the pipe, which further improves the service life of the unit. Attached Figure Description
[0017] Figure 1 This is a perspective view of a waste heat recovery unit for dyeing and printing wastewater proposed in this utility model;
[0018] Figure 2 This is a schematic diagram of the ultrasonic filter structure of a waste heat recovery unit for dyeing and printing wastewater proposed in this utility model.
[0019] Figure 3 This is a schematic diagram of the filter structure of a waste heat recovery unit for dyeing and printing wastewater proposed in this utility model;
[0020] Figure 4 This is a schematic diagram of the sliding frame structure of a waste heat recovery unit for dyeing and printing wastewater proposed in this utility model.
[0021] Legend:
[0022] 1. Cold water tank; 2. Electromagnetic flow meter; 3. Heat exchanger II; 4. Energy storage tank; 5. Electromagnetic check valve; 6. Pressure reducing valve; 7. Cold air pipe; 8. Hot air pipe; 9. Sewage pipe; 10. Support frame; 11. Heat exchanger I; 12. Water pump; 13. Ultrasonic filter; 14. Control panel; 15. Filter; 16. Wastewater tank; 17. Three-way valve I; 18. Three-way valve II; 19. Sliding frame; 20. Filter screen frame; 21. Rotary baffle; 22. Sliding groove; 23. Concave slider; 24. Cleaning port; 25. Filter port; 26. Drain outlet; 27. Locking block. Detailed Implementation
[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0024] Reference Figure 1-3 This utility model provides an embodiment of a waste heat recovery unit for dyeing and printing wastewater, comprising a cold water tank 1, a heat exchanger 2 connected to the cold water tank 1 via a pipe and equipped with an electromagnetic flow meter 2, a heat exchanger 11 connected to the left front end of the heat exchanger 2 via a hot air pipe 8, a cold air pipe 7 connected to the right rear end of the heat exchanger 11 and the right front end of the heat exchanger 2 3, a drain pipe 9 fixedly connected to the right side of the heat exchanger 11, and an energy storage tank 4 connected to the right side of the heat exchanger 2 via a pipe and equipped with a pressure reducing valve 6. An ultrasonic filter 13 is connected to the left side of heat exchanger 11 via a pipe, and a water pump 12 and a three-way valve 17 are installed on the pipe. A filter 15 and a three-way valve 18 are connected to the left side of ultrasonic filter 13 via a pipe. During filtration, the water passes through filter 15 and ultrasonic filter 13. A conductivity sensor is installed at the outlet of ultrasonic filter 13 for detection. If the detection fails, the control panel 14 will control three-way valves 17 and 18 to re-filter the wastewater. After filtration, the corrosiveness is greatly reduced, decreasing the probability of heat exchanger 11 corrosion and improving the unit's lifespan. A rotating component is installed inside filter 15, and a wastewater tank 16 is connected to the left side of filter 15 via a pipe.
[0025] Reference Figure 1 , Figure 3 and Figure 4The rotating assembly includes a sliding frame 19, with a rotating groove on the rear side of the sliding frame 19. A filter screen frame 20 is rotatably connected inside the rotating groove. A rotating baffle 21 is fixedly connected to the front end of the inner wall of the sliding frame 19. A slot is provided on the rear side of the sliding frame 19, and a locking block 27 is slidably connected inside the slot. A filter port 25 is provided at the top of the filter 15, a drain port 26 is provided on the bottom side of the filter 15, and a water outlet is provided at the bottom right side of the filter 15. Two cleaning ports 24 are provided on the front side of the filter 15. When cleaning the filter 15, the locking block 27 is removed and the filter screen frame 20 is rotated to tilt it. The cleaning ports 24 and the drain port 26 are opened, and a high-pressure water gun is used to clean the filter screen and the inner wall of the filter 15. The filtered material is discharged through the drain port 26. An energy storage outlet is provided on the rear side of the energy storage tank 4, and an electromagnetic one-way valve 5 is connected inside the energy storage outlet through a pipe. Support frames 10 are fixedly connected to the left and right ends of the outer walls of heat exchanger 11 and heat exchanger 3. Wastewater outlet is located at the bottom right side of wastewater tank 16, and cold water outlet is located at the bottom right side of cold water tank 1. A sliding groove 22 is provided inside the sliding frame 19, and a concave slider 23 is slidably connected inside the sliding groove 22. A filter screen is installed inside the filter screen frame 20. The filter screen frame 20 is pulled out for replacement. Water pumps 12 are installed on all pipes. A control groove is located at the top front of the ultrasonic filter 13, and a control panel 14 is installed inside the control groove.
[0026] Working principle: Wastewater discharged into wastewater pool 16 is transported to filter 15 through pipes and pump 12. The pipes are coated with a ceramic anti-corrosion coating. The wastewater undergoes pretreatment filtration through filter 15, removing suspended solids. A coagulant is added to coagulate colloidal particles into larger flocs, which are then filtered through sedimentation and a filter screen. When cleaning filter 15, the retaining block 27 is removed and the filter screen frame 20 is rotated to tilt it. The cleaning port 24 and drain port 26 are opened, and a high-pressure water gun is used to clean the filter screen and the inner wall of filter 15. Filtered material is discharged through drain port 26. When replacing the filter screen, the filter screen frame 20 is pulled out for replacement. After pretreatment by filter 15, the wastewater is then transported to ultrasonic filtration. Inside the filter 13, water flows through the filter screen to remove fine impurities. As various pollutants in the filter medium accumulate inside the filter screen, the filter channel becomes clogged, and the pressure difference between the inlet and outlet gradually increases. When the pressure difference reaches the preset value, the system automatically starts the stroke motor and the backwash high-pressure pump to clean the filter screen. A conductivity sensor is installed at the outlet. Dyeing and printing wastewater usually contains a large amount of electrolytes, such as dyes, auxiliaries, and some salts. These substances will make the dyeing and printing wastewater have a high conductivity. Based on the conductivity characteristics of electrolyte solutions, the conductivity is reflected by measuring the conductivity of the solution. If the conductivity is too high, the three-way valve 17 and the three-way valve 28 will be controlled by the control panel 14 to filter the wastewater again.
[0027] After filtration, the corrosivity is greatly reduced, which reduces the probability of heat exchanger 11 corrosion caused by corrosion and improves the service life of the unit. After heat exchange between heat exchanger 11 and heat exchanger 23, heat is transferred from the hot fluid to the cold fluid to achieve heating. Wastewater is discharged from the drain pipe 9. When cold water passes through the measuring tube of electromagnetic flowmeter 2, an induced potential proportional to the flow rate is generated on the electrode. The flow rate of the fluid is calculated by measuring this potential and enters heat exchanger 23 in an appropriate ratio. After heating, it enters the printing and dyeing equipment through the pipeline. When the amount of heated water exceeds the required amount, the pressure reducing valve 6 will open and enter the energy storage tank 4 for storage. When needed, it is delivered to the printing and dyeing equipment through the electromagnetic check valve 5 and water pump on the back side.
[0028] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.
Claims
1. A waste heat recovery unit for dyeing and printing wastewater, characterized in that, The system includes a cold water tank (1), which is connected to a second heat exchanger (3) via a pipe and is equipped with an electromagnetic flow meter (2). The left front end of the second heat exchanger (3) is connected to a first heat exchanger (11) via a hot air pipe (8). The right rear end of the first heat exchanger (11) is connected to the right front end of the second heat exchanger (3) via a cold air pipe (7). A drain pipe (9) is fixedly connected to the right side of the first heat exchanger (11). A storage tank is connected to the right side of the second heat exchanger (3) via a pipe. The energy box (4) is equipped with a pressure reducing valve (6) on the pipeline. The left side of the heat exchanger (11) is connected to an ultrasonic filter (13) through a pipeline, and a water pump (12) and a three-way valve (17) are installed on the pipeline. The left side of the ultrasonic filter (13) is connected to a filter (15) and the heat exchanger (11) through a pipeline, and a three-way valve (18) is installed on the pipeline. The filter (15) is equipped with a rotating component inside. The left side of the filter (15) is connected to a wastewater tank (16) through a pipeline.
2. The waste heat recovery unit for dyeing and printing wastewater according to claim 1, characterized in that: The rotating assembly includes a sliding frame (19), a rotating groove is provided on the rear side of the sliding frame (19), a filter screen frame (20) is rotatably connected inside the rotating groove, a rotating baffle (21) is fixedly connected to the front end of the inner wall of the sliding frame (19), a slot is provided on the rear side of the sliding frame (19), and a locking block (27) is slidably connected inside the slot.
3. The waste heat recovery unit for dyeing and printing wastewater according to claim 1, characterized in that: The filter (15) has a filter port (25) at the top, a drain port (26) at the bottom, a water outlet at the bottom right side, and two cleaning ports (24) at the front.
4. The waste heat recovery unit for dyeing and printing wastewater according to claim 1, characterized in that: The energy storage box (4) has an energy storage outlet on its rear side, and the inside of the energy storage outlet is connected to an electromagnetic one-way valve (5) through a pipe.
5. The waste heat recovery unit for dyeing and printing wastewater according to claim 1, characterized in that: The left and right ends of the outer walls of heat exchanger one (11) and heat exchanger two (3) are fixedly connected to support frames (10).
6. The waste heat recovery unit for dyeing and printing wastewater according to claim 1, characterized in that: Wastewater outlet is provided at the bottom right side of the wastewater pool (16), and cold water outlet is provided at the bottom right side of the cold water pool (1).
7. The waste heat recovery unit for dyeing and printing wastewater according to claim 2, characterized in that: The sliding frame (19) has a sliding groove (22) inside, and a concave slider (23) is slidably connected inside the sliding groove (22). The filter screen frame (20) is provided with a filter screen inside.
8. The waste heat recovery unit for dyeing and printing wastewater according to claim 1, characterized in that: Each of the pipes is equipped with a water pump (12), and the front top of the ultrasonic filter (13) is provided with a control slot, and a control panel (14) is provided in the control slot.