Waste heat recovery device

Abstract

The utility model discloses a waste heat recovery device which comprises a cooling air duct and an air return duct, an air outlet of the cooling air duct is connected with an air inlet of the air return duct, a surface air cooler is arranged in the cooling air duct, the air return duct is arranged on the peripheral side of the surface air cooler in a surrounding mode, and an air-air heat exchange assembly is arranged in the air return duct in an embedded mode. The gas-gas heat exchange assembly comprises longitudinal gas channels and transverse gas channels which are arranged in an up-down staggered mode, a waste liquid storage tank is arranged below the cooling air channel, and the waste liquid storage tank is connected with the cooling air channel through a waste liquid collecting pipe; when waste heat is recycled, discharged gas firstly passes through the two-stage cooling system, after the temperature is reduced, gaseous NMP can be effectively liquefied into liquid to flow out and be collected together, then cooled and purified cold air absorbs heat again when flowing back to the coating machine again, and the heat is recycled. Meanwhile, the waste heat gas before flowing into the cooling system is primarily cooled; and potential safety hazards caused by excessive gathering of NMP in the coating machine are avoided.

Description

Technical Field

[0001] The utility model relates to the technical field related to waste heat recovery, and in particular to a waste heat recovery device. Background Art

[0002] During production, the coater needs to inhale gas from the surrounding area to heat and perform processing. Since the heat accumulated during coating will also be discharged from the exhaust gas, how to recycle the exhaust gas with heat into the coater for reuse to reduce the energy consumption required for heating is a problem to be solved.

[0003] There is a coating machine with a waste heat recovery and reuse mechanism, the patent number is CN202121782165.0, a coating machine with a waste heat recovery and reuse mechanism, the utility model includes a supporting assembly, a recovery assembly and a drying assembly, the recovery assembly is rotatably connected to the supporting assembly, the drying assembly is fixedly connected to the supporting assembly, the recovery assembly includes a recovery groove and a connecting ring, both ends of the top of the recovery groove are clamped with connecting rings, the drying assembly includes a drying chamber, an air intake part and an exhaust part, the exhaust part is fixedly connected to the outer wall of the drying chamber, and the air intake part is fixedly connected to the top of the drying chamber.

[0004] The above-mentioned coating machine has the function of recycling waste heat, but it ignores the NMP generated by the coating machine and diffuses it into the exhaust gas. When recycling, it does not pay attention to isolating the NMP, resulting in the continuous accumulation of NMP in the coating machine during recycling, which will cause safety hazards. Utility Model Content

[0005] The purpose of the utility model is to provide a waste heat recovery device to overcome the deficiencies in the prior art.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] A waste heat recovery device comprises a cooling air duct and a return air duct, the air outlet of the cooling air duct is connected with the air inlet of the return air duct, a surface cooler is arranged in the cooling air duct, the return air duct is arranged around the surface cooler, an air-to-air heat exchange component is embedded in the return air duct, the air-to-air heat exchange component comprises a longitudinal air duct and a transverse air duct, the longitudinal air duct and the transverse air duct are arranged alternately up and down, the longitudinal air duct is communicated with the air inlet of the cooling air duct, the transverse air duct is arranged in the return air duct for conduction inside the return air duct, a waste liquid storage tank is arranged below the cooling air duct, and the waste liquid storage tank is connected to the cooling air duct through a waste liquid collecting pipe.

[0008] To further explain, the surface cooler includes a cooling water surface cooler and a refrigerated water surface cooler; one side of the cooling water surface cooler is connected to a cooling water inlet pipe and a cooling water outlet pipe; one side of the refrigerated water surface cooler is connected to a refrigerated water inlet pipe and a refrigerated water outlet pipe.

[0009] To further explain, a waste liquid collecting pipe is fixedly arranged on the top of the waste liquid tank, and the waste liquid tank is connected to the inside of the cooling air duct through the waste liquid collecting pipe. The waste liquid tank is used to collect the waste liquid flowing down the cooling air duct.

[0010] It is further explained that a pressurized filler, a pressurized guide plate and a return air guide plate are installed inside the return air duct. The pressurized guide plate is located at the corner near the return air duct inlet, the return air guide plate is located at the corner near the return air duct outlet, and the pressurized guide plate is arranged between the pressurized guide plate and the return air guide plate to increase the pressure of the internal circulating gas and increase the flow rate.

[0011] To further explain, the host frame includes a cooling air duct and a return air duct which are fixedly arranged in the host frame.

[0012] To further explain, a waste liquid extraction port is provided on one side of the waste liquid tank near the bottom for discharging the waste liquid stored in the waste liquid tank.

[0013] To further explain, temperature sensors are fixedly installed at the air inlet of the return air duct, the air outlet of the return air duct and the air inlet of the cooling air duct.

[0014] To further explain, a return air port for connecting to the coating machine is provided at the end of the return air duct, and an exhaust gas diversion port is also provided at the top of the return air port.

[0015] Compared with the prior art, the beneficial effects of the utility model are as follows:

[0016] When the utility model recovers waste heat, the discharged gas is first passed through a secondary cooling system. After the temperature is lowered, the gaseous NMP can be effectively liquefied into liquid and flowed out and collected together. Then, the cooled and purified cold air (which is colder than the waste gas just discharged) will absorb heat again when it flows back to the coating machine, and at the same time, the waste heat gas before flowing into the cooling system will be initially cooled, so as to avoid excessive accumulation of NMP inside the coating machine to cause safety hazards. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the structure of the utility model with three-dimensional ignoring the sealing plate;

[0018] Figure 2 This is a schematic diagram of the internal structure of the surface cooler of the utility model;

[0019] Figure 3 This is a schematic diagram of the structure of the utility model ignoring the return air duct sheet metal and sealing plate;

[0020] Figure 4 This is a side view of the utility model ignoring the return air duct sheet metal and sealing plate.

[0021] Notes on the attached drawings:

[0022] 1. Temperature sensor; 2. Pressurization guide plate; 3. Surface cooler; 4. Pressurization filler; 5. Air-to-air heat exchange assembly; 6. Chilled water inlet pipe; 7. Chilled water outlet pipe; 8. Cooling water inlet pipe; 9. Cooling water outlet pipe; 10. Return air port; 11. Host frame; 12. Waste liquid extraction port; 13. Waste liquid storage tank; 14. Exhaust gas diversion port; 15. Return air guide plate; 16. Waste liquid collection pipe; 301. Cooling water surface cooler; 302. Chilled water surface cooler; 17. Cooling air duct; 18. Return air duct. DETAILED DESCRIPTION

[0023] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the utility model. However, the utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the utility model, so the utility model is not limited by the specific embodiments disclosed below.

[0024] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. When the number of an element is referred to as "plurality", it may be any number of two or more. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the technical field of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific implementations and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0026] The present invention is described in detail below in conjunction with the embodiments shown in the accompanying drawings:

[0027] like Figure 1-4As shown, in this embodiment, a waste heat recovery device is provided, including a cooling air duct 17 and a return air duct 18. The cooling air duct 17 cools the hot air sent in, and then flows back into the coating machine through the return air duct 18. The air outlet of the cooling air duct 17 is connected to the air inlet of the return air duct 18, and the gas cooled in the cooling air duct 17 flows into and out of the return air duct 18.

[0028] The cooling air duct 17 is provided with a surface cooler 3, and the return air duct 18 is arranged around the surface cooler 3. The return air duct 18 is embedded with an air-to-air heat exchange component 5, and the air-to-air heat exchange component 5 includes a longitudinal air duct and a transverse air duct. The optional longitudinal air duct is used to connect the air supply port of the coating machine, and the hot air released will flow into the cooling air duct 17 along the longitudinal air duct for cooling and heat dissipation; the longitudinal air duct and the transverse air duct are arranged in an up-and-down staggered manner, and the longitudinal air duct is connected to the air inlet of the cooling air duct 17, and the transverse air duct is arranged in the return air duct 18. It is used for conduction inside the return air duct 18, and the cold air (which has a lower temperature than the hot air just entering the cooling air duct 17) that has passed through the cooling air duct 17 will flow into the return air duct 18, and the cold air in the return air duct 18 will be heated by the above-mentioned air-to-air heat exchange component 5 to reach the temperature required by the coating machine for reflux and reuse. The air-to-air heat exchange component 5 will make two gases with different temperatures interweave and alternate the temperatures, the hot air will undergo a preliminary cooling, and the cold air will reabsorb the heat for heat reuse.

[0029] A waste liquid storage tank 13 is provided below the cooling air duct 17, and the waste liquid storage tank 13 is connected to the cooling air duct 17 through a waste liquid collecting pipe 16. When the hot air passes through the surface cooler 3, NMP and part of the gas will dissipate heat and liquefy into water droplets and drip to the bottom of the cooling air duct 17. After gathering to a certain extent, they will converge into the waste liquid storage tank 13 below. In this embodiment, the purpose of the surface cooler 3 is to separate the NMP in the gas from the gas by cooling it. This step can reduce the concentration of NMP in the reflux gas; when the temperature is reduced, the NMP in the exhaust gas will be separated from the air.

[0030] In this embodiment, the surface cooler 3 includes a cooling water surface cooler 301 and a refrigerated water surface cooler 302; one side of the cooling water surface cooler 301 is connected to a cooling water inlet pipe 8 and a cooling water outlet pipe 9; one side of the refrigerated water surface cooler 302 is connected to a refrigerated water inlet pipe 6 and a refrigerated water outlet pipe 7. The cooling water surface cooler 301 is used to load cooling water, and the temperature of the cooling water is 18-30 degrees Celsius. The refrigerated water surface cooler 302 is used to load refrigerated water, and the temperature of the refrigerated water is 7-12 degrees Celsius. The cooling water surface cooler 301 is installed near the air inlet of the cooling air duct 17, and the refrigerated water surface cooler 302 is installed near the air inlet of the cooling air duct 17. After the hot air enters the cooling air duct 17, it first passes through the cooling water surface cooler 301 and then flows through the refrigerated water surface cooler 302; the hot air is cooled in a transitional order to improve the cooling efficiency.

[0031] In this embodiment, a waste liquid collecting pipe 16 is fixedly provided on the top of the waste liquid tank, and the waste liquid tank is connected to the interior of the cooling air duct 17 through the waste liquid collecting pipe 16. The waste liquid tank is used to collect the waste liquid flowing down the cooling air duct 17, and NMP is separated from the gas in a liquid state and flows into the waste liquid tank.

[0032] In this embodiment, a pressurized filler 4, a pressurized guide plate 2 and a return air guide plate 15 are installed inside the return air duct 18. The pressurized guide plate 2 is located at a corner near the air inlet of the return air duct 18, and the return air guide plate 15 is located at a corner near the air outlet of the return air duct 18. The pressurized guide plate 2 is arranged between the pressurized guide plate 2 and the return air guide plate 15 to increase the pressure of the internal circulating gas and improve the flow rate. The pressurized filler 4 is composed of a plurality of ventilation plates, and the ventilation plates are provided with a plurality of ventilation holes.

[0033] To further explain, the main frame 11 , the cooling air duct 17 and the return air duct 18 are all fixedly disposed in the main frame 11 .

[0034] To further describe, a waste liquid extraction port 12 is provided near the bottom of the waste liquid tank to discharge the waste liquid stored in the waste liquid tank. When the stored waste liquid is full, the stored waste liquid can be extracted through the extraction port.

[0035] To further explain, the air inlet of the return air duct 18, the air outlet of the return air duct 18 and the air inlet of the cooling air duct 17 are respectively fixedly provided with temperature sensors 1, which can accurately detect the temperature of the gas and make timely adjustments.

[0036] To further explain, a return air port 10 for connecting to the coater is provided at the end of the return air duct 18, and an exhaust gas diversion port 14 is also provided at the top of the return air port 10. Most of the gas will flow back to the coater from the return air port 10 (about 90%) and part of the gas will flow out from the exhaust gas diversion port 14 (about 10%).

[0037] The air-to-air heat exchange assembly 5 specifically includes a frame and a heat exchange baffle fixedly connected to the frame. The heat exchange baffles are arranged at equal intervals in the frame. The heat exchange baffles divide the interior of the frame into multiple ventilation layers. Multiple baffles are fixedly arranged at equal intervals on the side of the frame. Each ventilation layer is symmetrically provided with baffles in front and back or left and right. If the baffles are symmetrically arranged in front and back of the ventilation layer, a transverse airway will be formed with the heat exchange baffle; if the baffles are symmetrically arranged in the left and right of the ventilation layer, a longitudinal airway will be formed with the heat exchange baffle.

[0038] Because the longitudinal airway and the transverse airway are arranged alternately, the baffles arranged front and back and left and right are arranged alternately up and down (plum blossom and bamboo arrangement); specifically, the baffles arranged symmetrically front and back and the baffles arranged symmetrically left and right are arranged alternately in the vertical direction.

[0039] The technical features of the above-mentioned embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification. For ordinary technicians in this field, they can make several modifications and improvements without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A waste heat recovery device, characterized in that: It includes a cooling air duct and a return air duct. The air outlet of the cooling air duct is connected with the air inlet of the return air duct. A surface cooler is arranged in the cooling air duct. The return air duct is arranged around the surface cooler. An air-to-air heat exchange component is embedded in the return air duct. The air-to-air heat exchange component includes a longitudinal air duct and a transverse air duct. The longitudinal air duct and the transverse air duct are arranged alternately up and down. The longitudinal air duct is connected with the air inlet of the cooling air duct. The transverse air duct is arranged in the return air duct for conduction inside the return air duct. A waste liquid storage tank is arranged below the cooling air duct, and the waste liquid storage tank is connected to the cooling air duct through a waste liquid collecting pipe.

2. The waste heat recovery device according to claim 1, characterized in that: The meter cooler includes a cooling water meter cooler and a freezing water meter cooler; one side of the cooling water meter cooler is connected to a cooling water inlet pipe and a cooling water outlet pipe; one side of the freezing water meter cooler is connected to a freezing water inlet pipe and a freezing water outlet pipe.

3. The waste heat recovery device according to claim 1, characterized in that: A waste liquid collecting pipe is fixedly arranged on the top of the waste liquid tank, and the waste liquid tank is connected with the inside of the cooling air duct through the waste liquid collecting pipe. The waste liquid tank is used to collect the waste liquid flowing down the cooling air duct.

4. The waste heat recovery device according to claim 1, characterized in that: The return air duct is equipped with a pressurized filler, a pressurized guide plate and a return air guide plate. The pressurized guide plate is located at the corner near the return air duct inlet, the return air guide plate is located at the corner near the return air duct outlet, and the pressurized guide plate is arranged between the pressurized guide plate and the return air guide plate to increase the pressure of the internal circulating gas and increase the flow rate.

5. The waste heat recovery device according to claim 1, characterized in that: It includes a mainframe frame, and the cooling air duct and the return air duct are fixedly arranged in the mainframe frame.

6. The waste heat recovery device according to claim 3, characterized in that: A waste liquid extraction port is provided on one side of the waste liquid tank near the bottom for discharging the waste liquid stored in the waste liquid tank.

7. The waste heat recovery device according to claim 1, characterized in that: Temperature sensors are fixedly arranged at the air inlet of the return air duct, the air outlet of the return air duct and the air inlet of the cooling air duct.

8. The waste heat recovery device according to claim 1, characterized in that: A return air port for connecting to the coating machine is arranged at the end of the return air duct, and an exhaust gas diversion port is also arranged at the top of the return air port.

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