Coating process exhaust air volume optimization structure

Abstract

The utility model discloses a kind of coating process exhaust air volume optimization structure, it is related to coating process technical field, including one layer coating machine and two layer coating machine, both include multiple ovens;One layer rear three section ovens exhaust is connected two layer front three section ovens fresh air opening through second return air pipe, two layer rear three section ovens exhaust is connected one layer front three section ovens fresh air opening through first return air pipe, each pipeline is equipped with control valve and exhaust fan.The structure realizes low VOCs exhaust gas cross reuse, reduces total exhaust volume, reduces rear end processing equipment cost and heating energy consumption, and is suitable for energy-saving and environmental protection optimization of double-layer coating machine.

Description

Technical Field

[0001] This utility model relates to the field of coating process technology, and in particular to a structure for optimizing the exhaust and return air volume in coating processes. Background Technology

[0002] In the existing exhaust and return air process of the double-layer coating machine, each section of the drying oven of the coating machine is equipped with an exhaust port, and the exhaust gas discharged from each exhaust port is directly sent to the back-end treatment equipment for treatment.

[0003] This traditional exhaust method has obvious drawbacks: Firstly, because the exhaust gas concentration is low before and after drying in the front and rear ovens, but the overall exhaust volume of the coating machine is large, the total amount of exhaust gas that the downstream processing equipment needs to handle increases. This not only increases the initial investment cost of the processing equipment, but also increases the operating energy consumption and maintenance costs of the equipment due to the increased processing volume. Secondly, the exhaust gas discharged from the oven usually has a certain temperature. After these high-temperature exhaust gases are directly discharged, the coating machine needs to continuously heat the newly introduced ambient temperature fresh air to maintain the drying temperature inside the oven, which results in a significant increase in the heating energy consumption of the coating machine itself, which is not conducive to the efficient use of energy. Utility Model Content

[0004] To address the technical problems existing in the background art, this utility model proposes an optimized structure for exhaust and return air volume in the coating process.

[0005] This utility model proposes an optimized structure for exhaust and return air volume in a coating process, comprising a first-layer coating machine and a second-layer coating machine. Both the first-layer and second-layer coating machines include multiple drying ovens arranged sequentially along their coating direction. The exhaust ports of the first three drying ovens located at the front end of the first-layer coating machine are connected to a first-layer exhaust pipe. The air inlets of the second three drying ovens located at the rear end of the second-layer coating machine are connected to a second-layer fresh air pipe. Each exhaust port of the second three drying ovens is connected to each air inlet of the first three drying ovens via a first return air pipe. The air inlets of the second three drying ovens located at the rear end of the first-layer coating machine are connected to a first-layer fresh air pipe. The exhaust ports of the second three drying ovens located at the front end of the second-layer coating machine are connected to a second-layer exhaust pipe. Each exhaust port of the first three drying ovens is connected to each air inlet of the second three drying ovens via a second return air pipe.

[0006] Furthermore, the first three sections of the oven on the first floor are designated as Section 1, Section 2, and Section 3, while the last three sections of the oven on the first floor are designated as Section N, Section N+1, and Section N+2.

[0007] Furthermore, the last three sections of the second-layer oven are set as sections M, M+1, and M+2, while the first three sections of the second-layer oven are set as sections 1, 2, and 3.

[0008] Furthermore, several control valves are installed in each section of the second-floor fresh air duct, the first-floor exhaust duct, the first return air duct, the first-floor fresh air duct, the second-floor exhaust duct, and the second return air duct.

[0009] Furthermore, the second-layer fresh air duct, the first-layer exhaust duct, the first return air duct, the first-layer fresh air duct, the second-layer exhaust duct, and the second return air duct are all made of corrosion-resistant metal.

[0010] Furthermore, exhaust fans are equipped at the exhaust ports of the first three sections of the first layer, the last three sections of the second layer, the last three sections of the first layer, and the first three sections of the second layer.

[0011] The beneficial effects of this utility model are as follows: By sending the low-VOC exhaust gas from the three drying ovens after the first layer coating machine into the three drying ovens before the second layer coating machine as fresh air through the first return air duct group, and simultaneously sending the low-VOC exhaust gas from the three drying ovens after the second layer coating machine into the three drying ovens before the first layer coating machine as fresh air through the second return air duct group, the recycling of low-concentration waste gas is realized, effectively reducing the total exhaust volume of the coating machine. This not only reduces the investment and operating costs of the downstream waste gas treatment equipment, but also reduces the energy consumption for heating fresh air due to the waste heat carried by the recycled waste gas, significantly improving the energy-saving, environmental protection, and economic efficiency of the coating process. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structure of this utility model.

[0013] In the diagram: 1. First layer coating machine; 11. First layer first three-section drying oven; 12. First layer last three-section drying oven; 2. Second layer coating machine; 21. Second layer last three-section drying oven; 22. Second layer first three-section drying oven; 3. Second layer fresh air duct; 4. First layer exhaust pipe; 5. First return air duct; 6. First layer fresh air duct; 7. Second layer exhaust pipe; 8. Second return air duct. Detailed Implementation

[0014] Reference Figure 1 The present invention proposes an optimized structure for exhaust and return air volume in a coating process, which mainly includes a first-layer coating machine 1, a second-layer coating machine 2, connecting pipe assemblies, and auxiliary control components, as detailed below: The single-layer coating machine 1 has 16 drying ovens arranged sequentially along the coating direction, and they are divided into the following categories according to their positions: The first three drying ovens 11 are ovens 1#, 2#, and 3#, located at the front end of the coating machine 1. The exhaust ports of ovens 1#, 2#, and 3# are combined and connected to the exhaust pipe 4 on the first floor, which can uniformly transport the unrecovered waste gas to the back-end treatment equipment. The air inlets of ovens 1#, 2#, and 3# are respectively connected to the first return air pipe 5, which is used to receive the fresh air returned from the coating machine 2 on the second floor. The three drying ovens 12 at the back of the first layer are ovens 14#, 15#, and 16#, located at the rear end of the coating machine 1 on the first layer. Their air inlets are connected to the fresh air duct 6 on the first layer to introduce external supplementary fresh air. The exhaust ports of ovens 14#, 15#, and 16# are respectively connected to the second return air duct 8 to send low-concentration waste gas back to the coating machine 2 on the second layer. The two-layer coating machine 2 is structurally symmetrical to the one-layer coating machine 1, and has 16 drying ovens arranged sequentially along the coating direction, which are divided into the following categories according to their positions: The three drying ovens 21 on the second floor are ovens 14#, 15#, and 16#, located at the rear of the coating machine 2 on the second floor. The air inlets of ovens 14#, 15#, and 16# are combined and connected to the fresh air duct 3 on the second floor to introduce external supplementary fresh air. The exhaust ports of ovens 14#, 15#, and 16# are respectively connected to the first return air duct 5 to return low-concentration waste gas to the coating machine 1 on the first floor. The first three sections of the second-layer drying oven 22 are ovens #1, #2, and #3, located at the front end of the second-layer coating machine 2. The exhaust ports of ovens #1, #2, and #3 are combined and connected to the second-layer exhaust pipe 7. Unrecovered waste gas is transported to the downstream processing equipment through this pipe. The air inlets of ovens #1, #2, and #3 are respectively connected to the second return air pipe 8 to receive fresh air returned from the last three sections of the first-layer drying oven 12. Butterfly valves, model D371X-16, are installed in the middle sections of the second-floor fresh air duct 3, the first-floor exhaust duct 4, the first return air duct 5, the first-floor fresh air duct 6, the second-floor exhaust duct 7, and the second return air duct 8. The air volume of each duct can be controlled manually or electrically (with a PLC control system) to adapt to different production loads, such as the air volume requirements when the substrate thickness and coating speed change. Each of the three oven sections 11 on the first floor, the three oven sections 21 on the second floor, the three oven sections 12 on the first floor, and the three oven sections 22 on the second floor is equipped with an axial flow exhaust fan at its exhaust port to provide power for the transport of exhaust gas and ensure stable airflow in the return air duct.

[0015] Work process: The low-VOC exhaust gas discharged from ovens #14, #15, and #16 of the last three ovens on the first floor 12 is transported to ovens #1, #2, and #3 of the first three ovens on the second floor 22 as fresh air by the exhaust fan and the second return air duct 8. If the return air volume is insufficient, external fresh air can be introduced through the first-floor fresh air duct 6 to supplement it. Excess exhaust gas is sent to the back-end treatment equipment through the second-floor exhaust duct 7. The low-VOC exhaust gas discharged from ovens #14, #15, and #16 of the last three sections of the second-layer drying oven 21 is transported as fresh air to ovens #1, #2, and #3 of the first three sections of the first-layer drying oven 11 via the first return air duct 5 under the action of its own exhaust fan. If the return air volume is insufficient, external fresh air can be introduced through the second-layer fresh air duct 3 to supplement it, and excess exhaust gas is sent to the downstream treatment equipment through the first-layer exhaust pipe 4. In addition, based on the real-time monitoring of exhaust gas concentration (a VOCs sensor can be installed in the return air duct) and oven temperature, the opening of the control valves of each pipe is adjusted to control the proportion of return air (usually 60%-80% of the total fresh air volume), ensuring that the reused exhaust gas meets the concentration requirements and maintains a stable temperature inside the oven (such as 60-80℃).

[0016] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A structure for optimizing exhaust and return air volume in a coating process, characterized in that, The system includes a first-layer coating machine (1) and a second-layer coating machine (2). Both the first-layer coating machine (1) and the second-layer coating machine (2) include multiple oven sections arranged sequentially along their coating direction. The first three oven sections (11) located at the front end of the first-layer coating machine (1) have their exhaust ports connected to the first-layer exhaust pipe (4). The second three oven sections (21) located at the rear end of the second-layer coating machine (2) have their air inlets connected to the second-layer fresh air pipe (3). Each exhaust port of the second three oven sections (21) is connected to the first three oven sections. Each air inlet of the oven (11) is connected to the first return air pipe (5); the air inlets of the three rear sections of the first-layer oven (12) located at the rear end of the first-layer coating machine (1) are connected to the first-layer fresh air pipe (6); the exhaust ports of the three front sections of the second-layer oven (22) located at the front end of the second-layer coating machine (2) are connected to the second-layer exhaust pipe (7); each exhaust port of the three rear sections of the first-layer oven (12) is connected to each air inlet of the three front sections of the second-layer oven (22) through the second return air pipe (8).

2. The structure for optimizing exhaust and return air volume in the coating process according to claim 1, characterized in that, The first three oven sections (11) of the first layer are set as Section 1, Section 2 and Section 3, and the last three oven sections (12) of the first layer are set as Section N, Section N+1 and Section N+2.

3. The structure for optimizing exhaust and return air volume in the coating process according to claim 1, characterized in that, The last three sections of the second-layer oven (21) are set as section M, section M+1 and section M+2, and the first three sections of the second-layer oven (22) are set as section 1, section 2 and section 3.

4. The structure for optimizing exhaust and return air volume in the coating process according to claim 1, characterized in that, Several control valves are installed in the sections of the second-floor fresh air duct (3), the first-floor exhaust duct (4), the first return air duct (5), the first-floor fresh air duct (6), the second-floor exhaust duct (7), and the second return air duct (8).

5. The structure for optimizing exhaust and return air volume in the coating process according to claim 1, characterized in that, The second-layer fresh air duct (3), the first-layer exhaust duct (4), the first return air duct (5), the first-layer fresh air duct (6), the second-layer exhaust duct (7), and the second return air duct (8) are all made of corrosion-resistant metal.

6. The structure for optimizing exhaust and return air volume in the coating process according to claim 1, characterized in that, The exhaust ports of the first three oven sections (11), the second three oven sections (21), the first three oven sections (12), and the second three oven sections (22) are all equipped with exhaust fans.

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