Drying control system for oil-proof paper production

Abstract

The utility model discloses a drying control system for oil-proof paper production, which comprises a back coating metering rod used for uniformly scraping and attaching oil-proof paint on the back surface of a paper sheet; the back coating metering rod is provided with an infrared drying assembly for performing thermal radiation drying on an oil-proof coating coated on the back surface of the paper sheet along the axial direction; a back coating hot air box for carrying out high-pressure steam hot air drying on the oil-proof coating on the back surface of the paper sheet is also arranged in the middle section of the oil-proof paper production line; the back coating hot air box is connected with a back coating hot air system through a pipeline; a drying cylinder steam admission drying system for further improving the drying capacity of the back surface of the paper sheet through steam admission of an upper-row cylinder is also arranged at the seven-drying state adjusting cylinder at the tail section of the oil-proof paper production line; the back surface of the oil-proof paper is comprehensively dried in a combined mode of gas infrared drying, coating hot air drying and drying cylinder steam inlet drying, the drying capacity of the back surface of the paper sheet is enhanced, the situation that a coating is not completely dried and adheres to a drying cylinder to form dirty points is avoided, the problem of paper web warping is also avoided, and the production quality of the oil-proof paper is effectively improved.

Description

Technical field

[0001] The utility model relates to a drying technology for oil-proof paper, in particular to a drying and baking control system for the production of oil-proof paper. [Background Technology]

[0002] The condensation system in the paper machine's drying section is crucial in the papermaking process. Controlling the steam drying process is crucial for paper quality and energy efficiency. Greaseproof paper requires a high latex content in the backside coating to achieve the required oil-proof grade. Furthermore, during the greaseproof paper production process, the latex oil-proof coating is typically evenly applied to the backside of the paper using a metering rod. The coating is then dried through infrared back coating and hot air oven coating to achieve the desired oil-proof effect.

[0003] However, in the prior art, when producing greaseproof paper, the back coating two exhaust infrared of the dryer is generally fully opened, and the back coating hot air box temperature control valve is 100% fully opened. The back drying capacity of the paper machine's steam drying is still insufficient, and the back coating still does not dry thoroughly, causing the greaseproof paper to stick to the cylinder surface of the seven drying and conditioning cylinders used for warpage adjustment, resulting in black stains on the back of the paper. The produced greaseproof paper does not meet the production quality requirements due to the large number of dirty spots on the back. [Utility Model Content]

[0004] The utility model provides a drying and baking control system for the production of greaseproof paper, which comprehensively dries the back of the greaseproof paper through an infrared drying component, a back-coating hot air system and a drying cylinder steam inlet drying system, effectively preventing black dirty spots from appearing on the back of the paper and improving the production quality of the greaseproof paper.

[0005] The technical solution adopted by the utility model to solve its technical problems is:

[0006] A drying and drying control system for greaseproof paper production, which uses a combination of infrared drying, hot air drying for coating, and steam drying in a drying cylinder to comprehensively dry the back of the greaseproof paper. It includes a back coating metering rod, which is used to evenly scrape the greaseproof coating onto the back of the paper.

[0007] The back coating metering rod is provided with an infrared drying component located above and behind the back coating metering rod in the axial direction, which is used to dry the oil-proof coating coated on the back of the paper sheet with 100% full-open heat radiation infrared drying;

[0008] In the middle section of the oil-proof paper production line that has been preliminarily dried by the infrared drying assembly, a back coating hot air box is provided for drying the oil-proof coating on the back of the paper with high-pressure steam hot air. The back coating hot air box is connected to the back coating hot air system through a pipeline.

[0009] At the end of the oil-proof paper production line, the seventh drying and conditioning cylinder used to adjust the warping of the oil-proof paper is also equipped with a drying cylinder steam inlet drying system that further improves the drying capacity of the back of the paper by introducing steam from the upper cylinder.

[0010] Preferably, the back coating hot air system includes a high-pressure steam pipeline, a low-pressure steam pipeline, a first steam inlet automatic valve, a condensate tank, a blower, a back coating hot air box and an exhaust motor. The branch pipeline of the high-pressure steam pipeline is connected to the first steam inlet automatic valve, the condensate tank and the blower in sequence. The high-pressure hot steam in the high-pressure steam pipeline automatically separates the condensate therein after passing through the condensate tank to form high-temperature and high-pressure hot air. The blower sprays the hot air through the air nozzle in the back coating hot air box to the back of the paper sheet. The residual air after the hot air in the back coating hot air box contacts the back of the paper sheet passes through the pipeline and is discharged into the low-pressure steam pipeline by the exhaust motor.

[0011] Preferably, a first stop valve for controlling the hot air on the pipeline is further provided on the pipeline between the air outlet of the condensation water tank and the blower.

[0012] Preferably, the low-pressure steam pipeline is also connected to a second stop valve, a three-way valve, a vapor-liquid separation tank and a drain pump in sequence, and the high-pressure steam inlet of the condensate tank is also bypassed and connected to a branch of the three-way valve; when the steam humidity in the high-pressure steam pipeline or the low-pressure steam pipeline is too high, the steam and water are separated by the vapor-liquid separation tank and then directly discharged by the drain pump.

[0013] Preferably, the drying cylinder steam inlet drying system includes a high-pressure steam pipeline, a low-pressure steam pipeline, seven drying cylinders and a condensate tank for steam-water separation. A high-pressure steam inlet pipeline and a low-pressure steam inlet pipeline respectively connected to the high-pressure steam pipeline and the low-pressure steam pipeline are provided on the upper side of the seven drying cylinders. A second steam inlet valve and a third steam inlet valve for controlling the on-off of the pipeline and the amount of steam inlet are respectively installed on the high-pressure steam inlet pipeline and the low-pressure steam inlet pipeline. The steam inlet pressure of the seven drying cylinders is adjusted by the third steam inlet valve; the lower side of the seven drying cylinders is connected to a steam-water discharge pipeline, which discharges the steam-water mixture discharged from the seven drying cylinder group into the condensate tank.

[0014] Preferably, the lower part of the condensate tank is respectively connected with two main drainage pipelines and auxiliary drainage pipelines arranged in parallel. The main drainage pipeline is equipped with a main condensate pump which is automatically interlocked and opened when the liquid level in the condensate tank is higher than 50%, and which is automatically interlocked and stopped when the liquid level in the condensate tank is lower than 20%; the auxiliary drainage pipeline is equipped with an auxiliary condensate pump which is automatically interlocked and opened when the liquid level in the condensate tank is higher than 60%, and which is automatically interlocked and stopped when the liquid level in the condensate tank is lower than 50%; the main condensate pump and the auxiliary condensate pump send the discharged condensate to the boiler room or discharge it directly outside.

[0015] Preferably, a branch is connected to the top side of the condensate tank, which mixes the exhaust gas with high-pressure steam through a heat pump and then recycles it to the upper exhaust cylinder of the seventh drying machine for secondary utilization. The exhaust gas recovery pipeline is provided with a drain valve for controlling the on-off of the pipeline. When the machine is shut down, the drain valve is opened to discharge the exhaust gas directly into the atmosphere through the branch pipe of the exhaust gas recovery pipeline.

[0016] The beneficial effects of the utility model are:

[0017] Through the infrared drying components, back coating hot air system and drying cylinder steam drying system, during the production process of grease-proof paper, preliminary air infrared drying, secondary coating hot air drying and final drying cylinder steam drying are carried out, realizing a combined mode for comprehensive drying of the back of the grease-proof paper. This effectively prevents warping at the end of the grease-proof paper production line and black spots on the back of the paper, effectively improving the production quality and production efficiency of grease-proof paper.

Brief Description of the Drawings

[0018] Figure 1 It is a schematic diagram of the system principle of the utility model. [Specific implementation method]

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0020] A drying and drying control system for the production of greaseproof paper, which uses a combination of air-infrared drying, coating hot air drying, and drying cylinder steam drying to comprehensively dry the back of the greaseproof paper. It includes a back-coating metering rod (not shown) for evenly scraping the greaseproof coating onto the back of the paper sheet. An infrared drying assembly (not shown) is located above and behind the back-coating metering rod in the axial direction and is used to fully open the heat radiation infrared drying of the greaseproof coating applied to the back of the paper sheet. Figure 1 As shown, in the middle section of the oil-proof paper production line after the initial drying by the infrared drying component, a back coating hot air box 6 for drying the oil-proof coating on the back of the paper with high-pressure steam hot air is provided. The back coating hot air box 6 is connected to the back coating hot air system through a pipeline; Figure 1As shown, the back coating hot air system includes a high-pressure steam pipeline 1, a low-pressure steam pipeline 2, a first steam inlet automatic valve 3, a condensate tank 4, a blower 5, a back coating hot air box 6 and an exhaust motor 7. The branch pipeline of the high-pressure steam pipeline 1 is connected to the first steam inlet automatic valve 3, the condensate tank 4 and the blower 5 in sequence. A first stop valve 8 for controlling the hot air on the pipeline is also provided on the pipeline between the air outlet of the condensate tank 4 and the blower 5; the high-pressure hot steam in the high-pressure steam pipeline 1 automatically separates the condensed water therein after passing through the condensate tank 4 to form high-temperature and high-pressure hot air, and the blower 5 sprays the hot air through the nozzle in the back coating hot air box 6 to the back of the paper sheet. The residual air after the hot air in the back coating hot air box 6 contacts the back of the paper sheet passes through the pipeline and is discharged into the low-pressure steam pipeline 2 by the exhaust motor 7.

[0021] Among them, the low-pressure steam pipeline 2 is also connected to the second stop valve 9, the three-way valve 10, the vapor-liquid separation tank 11 and the drainage pump 12 in sequence, and the high-pressure steam inlet of the condensate tank 4 is also bypassed and connected to a branch of the three-way valve 10; during operation, when the steam humidity in the high-pressure steam pipeline 1 or the low-pressure steam pipeline 2 is too high, the steam and water are separated by the vapor-liquid separation tank 11 and then directly discharged by the drainage pump 12.

[0022] Continue as Figure 1 As shown, at the tail section of the oil-proof paper production line, the seventh drying and conditioning cylinder for adjusting the warping of the oil-proof paper is also provided with a drying cylinder steam inlet drying system for further improving the drying capacity of the back side of the paper sheet by introducing steam from the upper cylinder. The drying cylinder steam inlet drying system includes a high-pressure steam pipeline 1, a low-pressure steam pipeline 2, a seventh drying upper cylinder 13 and a condensate tank 14 for steam-water separation. A high-pressure steam inlet pipeline and a low-pressure steam inlet pipeline connected to the high-pressure steam pipeline 1 and the low-pressure steam pipeline 2 are provided on the upper side of the seventh drying upper cylinder 13 respectively. A second steam inlet valve 15 and a third steam inlet valve 16 for controlling the on-off of the pipeline and the amount of steam inlet are respectively installed on the high-pressure steam inlet pipeline and the low-pressure steam inlet pipeline, and the steam inlet pressure of the seventh drying upper cylinder 13 is adjusted by the third steam inlet valve 16; a steam-water discharge pipeline 17 is connected to the lower side of the seventh drying upper cylinder 13, and the steam-water discharge pipeline 17 discharges the steam-water mixture discharged from the seventh drying cylinder group into the condensate tank 14.

[0023] Continue as Figure 1As shown, the lower part of the condensate tank 14 is connected to two parallel main drainage pipes 18 and auxiliary drainage pipes 19. The main drainage pipe 18 is equipped with a main condensate pump 20 that automatically opens when the liquid level in the condensate tank 14 is higher than 50%, and automatically stops when the liquid level in the condensate tank 14 is lower than 20%. The auxiliary drainage pipe 19 is equipped with an auxiliary pump that automatically opens when the liquid level in the condensate tank 14 is higher than 60%, and automatically stops when the liquid level in the condensate tank 14 is lower than 50%. Condensate pump 21; the main condensate pump 20 and the auxiliary condensate pump 21 send the discharged condensate to the boiler room or directly discharge it outside; a branch is also connected on the top side of the condensate tank 14, and the exhaust gas is mixed with high-pressure steam through the heat pump 22 and then recycled to the seventh drying upper cylinder 13 for secondary utilization. The exhaust gas recovery pipeline 23 is provided with an emptying valve 24 for controlling the on-off of the pipeline. When the machine is shut down, the emptying valve 24 is opened to discharge the exhaust gas directly into the atmosphere through the branch pipe of the exhaust gas recovery pipeline 23.

[0024] In this embodiment, during the production process of greaseproof paper, preliminary infrared drying, secondary coating hot air drying and final drying by steam inlet are carried out in sequence through an infrared drying component, a back coating hot air system and a drying cylinder steam inlet drying system, thereby realizing a combined mode for comprehensive drying of the back side of the greaseproof paper, effectively preventing warping at the end of the greaseproof paper production line and black spots on the back side of the paper, and effectively improving the production quality and efficiency of the greaseproof paper.

[0025] The above-described embodiments are merely preferred embodiments of the present invention and are not intended to limit the scope of implementation of the present invention. Any equivalent changes based on the shape, structure, and principle of the present invention should be included in the scope of protection of the present invention.

Claims

1. A drying control system for oil-proof paper production, which uses a combination of air infrared drying, coating hot air drying and drying cylinder steam drying to comprehensively dry the back of the oil-proof paper, characterized in that: It includes a back coating metering rod, which is used to scrape the oil-proof coating evenly onto the back of the paper sheet; The back coating metering rod is provided with an infrared drying component located above and behind the back coating metering rod in the axial direction, which is used for 100% full-open heat radiation infrared drying of the oil-proof coating coated on the back of the paper sheet; A back coating hot air box is also provided in the middle section of the oil-proof paper production line after the preliminary drying by the infrared drying assembly to dry the oil-proof coating on the back of the paper with high-pressure steam hot air. The back coating hot air box is connected to the back coating hot air system through a pipeline. At the tail end of the oil-proof paper production line, the seven drying and conditioning cylinders for adjusting the warping of the oil-proof paper are also equipped with a drying cylinder steam inlet drying system that further improves the drying capacity of the back side of the paper sheets by inletting steam from the upper cylinder.

2. A drying control system for oil-proof paper production according to claim 1, characterized in that: The back coating hot air system includes a high-pressure steam pipeline, a low-pressure steam pipeline, a first steam inlet automatic valve, a condensate tank, a blower, a back coating hot air box and an exhaust motor. The branch pipeline of the high-pressure steam pipeline is connected to the first steam inlet automatic valve, the condensate tank and the blower in sequence. The high-pressure hot steam in the high-pressure steam pipeline automatically separates the condensate therein after passing through the condensate tank to form high-temperature and high-pressure hot air. The blower sprays the hot air through the air nozzle in the back coating hot air box to the back of the paper sheet. The residual air after the hot air in the back coating hot air box contacts the back of the paper sheet passes through the pipeline and is discharged into the low-pressure steam pipeline by the exhaust motor.

3. A drying control system for oil-proof paper production according to claim 2, characterized in that: A first stop valve for controlling the hot air on the pipeline is also provided on the pipeline between the air outlet of the condensing water tank and the blower fan.

4. A drying control system for oil-proof paper production according to claim 2, characterized in that: The low-pressure steam pipeline is also connected to a second stop valve, a three-way valve, a vapor-liquid separation tank and a drainage pump in sequence, and the high-pressure steam inlet of the condensate tank is also bypassed and connected to a branch of the three-way valve; when the steam humidity in the high-pressure steam pipeline or the low-pressure steam pipeline is too high, the steam and water are separated by the vapor-liquid separation tank and then directly discharged by the drainage pump.

5. The drying control system for oil-proof paper production according to claim 1, characterized in that: The drying cylinder steam inlet drying system includes a high-pressure steam pipeline, a low-pressure steam pipeline, seven drying cylinders and a condensate tank for steam-water separation. A high-pressure steam inlet pipeline and a low-pressure steam inlet pipeline respectively connected to the high-pressure steam pipeline and the low-pressure steam pipeline are arranged on the upper side of the seven drying cylinders. A second steam inlet valve and a third steam inlet valve for controlling the on-off of the pipeline and the amount of steam inlet are respectively installed on the high-pressure steam inlet pipeline and the low-pressure steam inlet pipeline. The steam inlet pressure of the seven drying cylinders is adjusted by the third steam inlet valve. The lower side of the seven drying cylinders is connected to a steam-water discharge pipeline, which discharges the steam-water mixture discharged from the seven drying cylinder groups into the condensate tank.

6. A drying control system for oil-proof paper production according to claim 5, characterized in that: The lower part of the condensate tank is respectively connected with two main drainage pipelines and auxiliary drainage pipelines arranged in parallel. The main drainage pipeline is equipped with a main condensate pump which is automatically opened when the liquid level in the condensate tank is higher than 50%, and is automatically stopped when the liquid level in the condensate tank is lower than 20%; the auxiliary drainage pipeline is equipped with an auxiliary condensate pump which is automatically opened when the liquid level in the condensate tank is higher than 60%, and is automatically stopped when the liquid level in the condensate tank is lower than 50%; the main condensate pump and the auxiliary condensate pump send the discharged condensate to the boiler room or discharge it directly outside.

7. A drying control system for oil-proof paper production according to claim 6, characterized in that: The top side of the condensate tank is also branched with an exhaust gas recovery pipeline that mixes the exhaust gas with high-pressure steam through a heat pump and then recovers it to the upper exhaust cylinder of the seventh drying machine for secondary utilization. The exhaust gas recovery pipeline is provided with a drain valve that controls the on-off of the pipeline. When the machine is shut down, the drain valve is opened to discharge the exhaust gas directly into the atmosphere through the branch pipe of the exhaust gas recovery pipeline.

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