Cleaning treatment device for recovered solvent

Abstract

The invention relates to the technical field of solvent treatment in the printing industry, and provides a recycled solvent cleaning treatment device which comprises a heat storage type thermal oxidizer used for combusting a solvent for harmless treatment. The air inlet duct is used for introducing high-temperature waste gas generated in the gravure process into the heat accumulating type thermal oxidizer; the volatilization box is arranged on the air inlet duct; the recovery solvent pipeline is communicated with the volatilization box, the tail end of the solvent pipeline is provided with an atomizing nozzle, and the recovery solvent is sprayed out of the special atomizing nozzle and enters the volatilization box. According to the technical scheme, the related problems of high investment cost, high safety risk, high implementation difficulty for a common printing factory and the like existing in a conventional mode that a recovered solvent is directly sprayed into the RTO combustion chamber at a high pressure in a liquid state for combustion treatment in the related technology are solved.

Description

Technical Field

[0001] The embodiments of the present disclosure relate to the technical field of solvent processing, and in particular, to a solvent recovery and cleaning disposal device. Background Art

[0002] During the gravure printing process, frequent order changes generate a large amount of waste solvent. Its main component is ethyl acetate used for cleaning, with a small amount of ethanol. Conventional treatment methods both domestically and internationally use simple distillation to distill the solvent. However, due to quality issues with the recovered solvent, the recovered solvent can generally only be reused for cleaning and cannot be used in production. In general, the amount of recovered solvent generated is far greater than the amount reused for cleaning, resulting in excess recovered solvent. Factories usually treat this as hazardous waste, but this presents the following problems: 1. Hazardous waste treatment will increase the company's hazardous waste treatment costs. Generally, the treatment cost per ton is around 5,000 yuan.

[0003] 2. As the amount of hazardous waste treated increases, the total amount of pollution produced by factories will increase. When the limit is reached, it will be included in the government's mandatory clean production supervision.

[0004] 3. Storing large amounts of recycled solvents will pose a great safety risk, and the consequences will be serious if a fire occurs.

[0005] In view of the above situation, the printing industry urgently needs to find a method to safely and environmentally friendly dispose of recycled solvents. The common practice in the market is to use a solvent injection system. There is currently a Chinese utility model patent with the application number: CN201320280233.2. It uses waste liquid as fuel and uses a high-pressure pump to atomize the solvent directly into a regenerative thermal oxidizer (RTO) at about 800 degrees for combustion to achieve harmless treatment of the recycled solvent. However, as the mainstream VOCs purification equipment in the printing industry, RTO has an excessively high internal combustion chamber temperature. Directly injecting flammable solvents into the combustion chamber requires large system investment, difficult operation and maintenance technology, high cost, high safety risks, and is prone to explosion. Moreover, the combustion and purification process inside the combustion chamber is uncontrollable, and there is a hidden danger of exceeding environmental standards. Therefore, even if many companies are equipped with RTOs with solvent injection systems, they will not activate them. Instead, they will need to spend extra money to treat the recycled solvents as hazardous waste. Summary of the Invention

[0006] To overcome the above-mentioned system defects, the embodiments of the present disclosure provide a recovered solvent cleaning and disposal device, which solves the technical problem that the existing RTO treatment device cannot directly process the recovered solvent.

[0007] According to one aspect, the present disclosure provides a recovery solvent cleaning and disposal device for cleaning a recovery solvent generated in a gravure printing process, comprising: A regenerative thermal oxidizer for burning the recovered solvent and purifying the exhaust gas generated by the combustion, wherein the regenerative thermal oxidizer has an air inlet duct for passing the high-temperature exhaust gas generated during the gravure printing process into the regenerative thermal oxidizer; a volatilization box, arranged on the main air intake pipe; The solvent pipeline is designed in accordance with the RTO configuration and has a pre-agreed maximum safe flow rate. The maximum solvent pipeline diameter is determined and the pipeline is connected to the volatilization box. The end of the solvent pipeline is provided with an atomizing nozzle. The low-viscosity (viscosity of approximately <2 mPa·s) recovery solvent is sprayed from the atomizing nozzle and enters the volatilization box. After the solvent is completely volatilized, it is in gaseous form and combined with the main fan to extract the high-temperature printing waste gas volatilized in the oven and enter the RTO in gaseous form.

[0008] For example, in a recovery solvent cleaning and disposal device provided in at least one embodiment of the present disclosure, the volatilization box includes: Box; A guide plate is arranged in the box body, and is used to guide the flow direction of the solvent droplets sprayed by the atomizing nozzle so that the recovered solvent can be completely volatilized in the volatilization box.

[0009] For example, in a solvent recovery cleaning and disposal device provided in at least one embodiment of the present disclosure, there are a plurality of guide plates, and the guide plates are arranged in an array, and the atomizing nozzles are facing the guide plates.

[0010] For example, in a solvent recovery and cleaning disposal device provided in at least one embodiment of the present disclosure, the solvent pipeline has a preheating section, which is located in the air intake duct. The preheating section is used to absorb the waste heat of the high-temperature exhaust gas in the air intake duct to heat the recovered solvent, facilitate solvent volatilization, and save energy.

[0011] For example, in a recovery solvent cleaning and disposal device provided in at least one embodiment of the present disclosure, the box body has an observation window and a cleaning port, and the recovery solvent cleaning and disposal device further includes: A feed pump is provided on the solvent pipeline, and is used to provide power for the flow of the recovered solvent; A regulating valve is provided on the solvent pipeline, and the regulating valve is used to regulate the flow of the recovered solvent in the solvent pipeline.

[0012] For example, in a solvent recovery cleaning and disposal device provided in at least one embodiment of the present disclosure, the housing further comprises: The guide member is used to change the flow direction of the high-temperature exhaust gas in the air intake duct so as to prolong the time that the high-temperature exhaust gas stays in the volatilization box.

[0013] For example, in a solvent recovery cleaning and disposal device provided in at least one embodiment of the present disclosure, the box is tilted and further includes: A plurality of first legs are provided on the box body; There are a plurality of second legs, which are arranged on the box body; the first legs and the second legs are used to support the box body.

[0014] For example, in a solvent recovery cleaning and disposal device provided in at least one embodiment of the present disclosure, the first leg is shorter than the second leg, the air inlet duct is located on a side of the box body close to the first leg, and further includes: A drainage pipeline is arranged on one side of the box body close to the first leg. The drainage pipeline is used to discharge the recovered solvent accumulated in the box body under abnormal circumstances, and to give an alarm in time to control the safety risk of sudden high-concentration exhaust gas.

[0015] For example, in a solvent recovery cleaning and disposal device provided in at least one embodiment of the present disclosure, a guide cone is provided at the diameter change point of the solvent pipeline.

[0016] The beneficial effects of the embodiments of the present disclosure are: The present disclosure relies on the company's existing RTO to clean the recovered solvent, but it is completely different from the existing conventional treatment method. The existing treatment method is to directly spray the recovered solvent liquid at high pressure into the RTO combustion chamber for combustion. The flame directly contacts the flammable solvent, which is prone to explosion. When this solution is in use, the volatilization box is set on the air intake duct to provide sufficient space for the volatilization of the recovered solvent. After the recovered solvent is sprayed into the volatilization box through the atomizing nozzle, it is volatilized by the heat of the high-temperature exhaust gas in the air intake duct, and all liquid recovered solvents are completely converted into gaseous state, which is convenient for subsequent full combustion in the regenerative thermal oxidizer. This volatilization feeding method avoids the risk of explosion that may be caused by spraying liquid solvent directly into the regenerative thermal oxidizer, and improves the safety of the treatment process. At the same time, this device can be linked to existing RTO internal safety control systems, such as the intake LEL explosion-proof control system, which can prevent explosions when high-concentration exhaust gas exceeding the standard enters the combustion chamber; the purge pipeline before startup, the direct connection to the fresh air valve during shutdown; the original system explosion vent; overheating alarms, etc. These alarms will be linked to the system to cut off the liquid supply. Therefore, the solvent is sprayed into the volatilization box for volatilization. The solvent evaporates into the system in a gaseous state. The principle is similar to the printing process, where the solvent evaporates in the hot air of the oven. It fully utilizes the high-speed airflow volatilization of the original exhaust gas and the safety devices of the existing RTO, thereby achieving safe, low-cost, efficient, and environmentally friendly purification of the recovered solvent, solving the problem of factory recycling solvent processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] To more clearly illustrate the technical solutions in the embodiments of the present disclosure, the following briefly introduces the drawings required for describing the embodiments of the present disclosure. Obviously, the drawings described below are merely some exemplary embodiments of the present disclosure. Those skilled in the art can, without inventive effort, derive other drawings based on the contents of the exemplary embodiments of the present disclosure and these drawings.

[0018] Figure 1 This is a process flow chart of a solvent recovery and cleaning device according to an embodiment of the present disclosure; Figure 2 A top view of a solvent recovery cleaning and disposal device according to an embodiment of the present disclosure; Figure 3 It is a structural schematic diagram of the volatilization box in the present disclosure; Figure 4 A schematic structural diagram of the volatilization box in the present disclosure from another perspective; Figure 5 is a cross-sectional schematic diagram of the volatilization box in the present disclosure; Figure 6 Schematic diagram of the internal structure of the volatilization box in the present disclosure; Figure 7 Schematic diagram of the structure of the solvent pipeline and atomizing nozzle in the present disclosure.

[0019] In the figure: 1. Regenerative thermal oxidizer, 2. Air inlet duct, 3. Volatilization box, 4. Solvent pipeline, 5. Atomizing nozzle, 6. Box body, 7. Guide plate, 8. Preheating section, 9. Observation window, 10. Cleaning port, 11. Feed pump, 12. Control valve, 13. Guide member, 14. First leg, 15. Second leg, 16. Drain pipeline. DETAILED DESCRIPTION

[0020] The present disclosure will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present disclosure, rather than to limit the present disclosure.

[0021] To simplify the drawings, only the parts relevant to the disclosure are schematically shown in each figure; they do not represent the actual structure of the product. Furthermore, to simplify the drawings and facilitate understanding, in some figures, only one of the components with the same structure or function is schematically shown or labeled. In this document, "one" not only means "only one" but also "more than one," and "several" includes "two" and "more than two."

[0022] It should be noted that, unless otherwise specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they can refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; and internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in this disclosure based on the specific circumstances.

[0023] In the present disclosure, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature includes the first feature being directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0024] In the description of this embodiment, the terms "up", "down", "left", "right", etc., and the orientation or position relationship are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the present disclosure.

[0025] In addition, in the description of the present application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0026] like Figures 1 to 7 The figure shows a recovered solvent cleaning and disposal device in one embodiment of the present disclosure. With the strengthening of national regulations on VOCs pollutants, the disposal of the large amount of recovered solvents generated by the gravure printing industry has become a key issue. Currently, gravure printing manufacturers are generally equipped with exhaust gas treatment devices (RTOs). Existing conventional solvent treatment methods typically involve directly spraying the solvent into the high-temperature RTO combustion chamber for combustion, which poses an explosion risk and is unsafe and uncontrollable.

[0027] The heat storage thermal oxidizer 1 is the core equipment for processing and recovering solvents. It uses high temperature to burn the solvent, decomposing organic pollutants into harmless substances such as carbon dioxide and water, thereby achieving harmless treatment of the exhaust gas generated by combustion. A heat storage ceramic body is usually provided inside. During the solvent combustion process, the heat storage ceramic body absorbs and stores heat. When new solvent enters, it is preheated using the heat of the stored exhaust gas, thereby improving combustion efficiency and reducing energy consumption. The composition of this device system mainly consists of a solvent storage device, a solvent pump, a connecting pipe, a solenoid valve and an injection head. The heat storage thermal oxidizer 1 itself has a safe maximum solvent load when the system is designed to ensure thorough solvent treatment.

[0028] This solution still relies on RTO to process the recovered solvent, but it is different from the existing conventional treatment method. The existing treatment method directly injects the recovered solvent into the RTO combustion chamber at high pressure for combustion. The flame directly contacts the flammable solvent, which is prone to explosion. When this solution is in use, the volatilization box 3 is set on the air inlet duct 2 to provide space for the volatilization of the recovered solvent. After the recovered solvent is sprayed into the volatilization box 3 through the atomizing nozzle 5, it is volatilized by using the high-speed and large-volume airflow and the heat of the high-temperature exhaust gas in the air inlet duct 2. The liquid recovered solvent is completely converted into gaseous state before entering the RTO system, which is convenient for subsequent full combustion in the regenerative thermal oxidizer 1. This method of feeding the solvent after volatilization avoids the risk of explosion that may be caused by spraying the liquid solvent directly into the regenerative thermal oxidizer 1, and improves the safety of the treatment process. In addition, the existing RTO system explosion-proof control device can prevent explosions when high-concentration exhaust gas enters the combustion chamber. Therefore, the solvent is sprayed into the volatilization box for volatilization, making full use of the high-speed flow of exhaust gas and the existing RTO safety device to achieve the processing of recovered solvents.

[0029] Solvent pipeline 4 transports recovered solvent to volatilization tank 3. A diaphragm pump (0.3-1 MPa) draws the solvent from a solvent drum in the cleaning room (the solvent must be kept away from the RTO site). After filtration, the solvent is transported through a stainless steel pipeline of defined diameter, equipped with electric valves, two-way shut-off valves, and manual valves. The solvent pipeline contains a 100-mesh Y-type filter with a filtration accuracy of 50u. A backflush function is designed to ensure the smooth flow of solvent pipeline 4. Before each startup, the pipeline is switched to the air line for backflush to ensure the smooth flow of solvent line 4. The atomizing nozzle 5 at the end sprays the recovered solvent into tiny droplets, increasing the solvent's surface area and allowing it to quickly contact and volatilize with the high-temperature exhaust gas in volatilization tank 3. The efficient atomization process allows the recovered solvent to evaporate quickly and mix with the high-temperature exhaust gas, creating optimal conditions for subsequent combustion. The solvent pipeline system is controlled and linked to the RTO, enabling liquid supply only during continuous production and automatically shutting off the supply in the event of an alarm.

[0030] Atomizing nozzle 5 features a dual-path design with an air-assisted atomizing nozzle constructed from 316L stainless steel, with a nozzle aperture ≤1mm. It also includes a quick-release anti-clogging mechanism and a purge feature. The liquid path of the nozzle transports the recovered solvent, while compressed air (0.4-0.8 MPa) is introduced into the air path through an annular chamber within the nozzle, thoroughly mixing the solvent and air. The compressed air forms a high-velocity airflow at the nozzle outlet, shearing the liquid into micron-sized droplets. This significantly improves solvent evaporation efficiency and enhances the nozzle's anti-clogging capabilities. However, in specific cases where the recovered solvent volume is smaller, a more economical mechanical atomizing nozzle can be used.

[0031] Before starting the system, check that the connections between the regenerative thermal oxidizer 1, volatilization box 3, solvent pipeline 4, and atomizing nozzle 5 are tight and leak-free. A solvent pipeline leak detection device may also be installed. Ensure that the flow control valve 12 and temperature sensor on the air intake duct 2 are functioning properly and accurately monitoring and controlling relevant parameters. Also, check that the supply of recovered solvent in the solvent pipeline 4 is unimpeded and that the atomizing nozzle 5 is not clogged. Gravure printing is ongoing, so high-temperature exhaust gas from the air intake duct 2 continuously flows into the regenerative thermal oxidizer 1. The recovered solvent is transported through the solvent pipeline 4 to the atomizing nozzle 5 and sprayed into the volatilization box 3. The high-temperature exhaust gas in the volatilization box 3 rapidly volatilizes the atomized recovered solvent, converting it into a gaseous state. This gaseous recovered solvent mixes with the high-temperature exhaust gas from the printing press and enters the regenerative thermal oxidizer 1. Within the regenerative thermal oxidizer 1, the solvent in the mixed gas is burned at high temperatures. The resulting exhaust gas undergoes high-temperature purification treatment within the combustion chamber, ensuring harmless discharge.

[0032] By volatilizing the recovered solvent in volatilization box 3 before feeding it into regenerative thermal oxidizer 1 for combustion, the explosion risk that could arise from directly injecting a flammable solvent in liquid form into a high-temperature combustion chamber is effectively avoided, ensuring safe handling of the recovered solvent. Simultaneously, the exhaust gas generated by combustion is harmlessly treated, reducing pollutant emissions and meeting environmental protection requirements. Furthermore, the waste heat from the high-temperature exhaust gas generated during the gravure printing process is utilized to volatilize the recovered solvent and preheat regenerative thermal oxidizer 1, reducing additional energy consumption, improving energy efficiency, and lowering processing costs.

[0033] An observation window 9 is provided on the volatilization box 3, providing the operator with a direct way to observe the internal conditions of the volatilization box 3. Through the observation window 9, the operator can observe in real time the atomization state and volatilization of the recovered solvent, as well as any abnormalities such as nozzle blockage or internal liquid accumulation, allowing timely action to ensure stable operation of the device. This enhanced visibility of device operation helps the operator promptly identify and address problems, avoiding poor treatment results or equipment failures caused by the inability to observe internal conditions, thereby enhancing the reliability and stability of the device. (Since the solvent injection system sprays into the combustion chamber, observation and adjustment within the high-temperature combustion chamber are extremely difficult and risky.) As the device operates, impurities and scale may accumulate inside the volatilization box 3, affecting the solvent volatilization effect and device performance. The provision of a cleaning port 10 facilitates regular maintenance of the volatilization box 3, removing these impurities and scale, keeping the interior of the volatilization box 3 clean, and ensuring continued stable operation of the device. A feed pump 11 is provided on the solvent pipeline 4 to provide power for the flow of the recovered solvent through the pipeline. Since the transportation of the recovered solvent needs to overcome certain resistances, such as the friction resistance of the pipeline and the pressure loss of the nozzle, the feed pump 11 can ensure that the recovered solvent is transported to the atomizing nozzle 5 at a stable flow rate and pressure, ensuring normal spraying and volatilization of the solvent.

[0034] The housing 6 forms the main structure of the volatilization chamber 3, providing space for the recovered solvent to evaporate. It features a tight seal to prevent leakage after solvent evaporation. It also must be able to withstand certain pressures and temperatures, ensuring its structural stability and preventing deformation or damage when high-temperature gravure printing exhaust gases pass through it. A deflector 7 is installed within the housing 6. Its primary purpose is to redirect the flow of solvent droplets sprayed by the atomizing nozzle 5, increasing their movement path and residence time within the volatilization chamber 3. This allows for more efficient heat exchange between the droplets and the high-temperature exhaust gases, ultimately achieving complete volatilization.

[0035] The atomizing nozzle 5 is directed toward the guide plate 7 to ensure that the sprayed solvent droplets directly impact the guide plate 7, thereby redirecting the droplets' motion and initiating the subsequent complex motion path and atomization process. This direct impact allows the droplets to disperse rapidly on the guide plate 7, increasing the contact area between the droplets and the high-temperature exhaust gas and accelerating volatilization. The guide plate 7 is a Teflon stainless steel grid plate that supports or distributes the liquid, ensuring full contact between the solvent and the air. This increased contact area allows for even distribution of the liquid within the pipe and promotes gas-liquid mixing.

[0036] In an actual operation case of this device, after stable production, based on natural gas consumption, such as 30L of natural gas per hour, the above is simply converted into the system requiring 30kg of recovered solvent. Therefore, based on the above product exhaust gas concentration, the manual selection can be made to set the flow rate of the electric valve to one of four levels: 10, 20, 30, or 40kg / hr. If an abnormality during production causes the basic high-temperature exhaust gas concentration to increase, combined with the concentration of the atomized volatile solvent in the volatile box, the RTO will overheat and alarm. At this time, the RTO alarm will alarm, and the system will cut off the solvent injection to ensure safety. This system and the existing RTO, as well as the safety alarms of the LEL and FID devices, are all linked and controlled. At the same time, the system can also choose to calculate the exhaust gas concentration based on the order ink volume and air volume system, or according to the LEL detection concentration lower limit requirements, combined with the system's self-heating required concentration, the system will automatically provide the basic safe flow rate of the electric valve to ensure system safety.

[0037] During the system design, this device has agreed upon and verified the maximum safe solvent volume based on the RTO configuration. The system safety at the maximum solvent volume is ensured by locking in the maximum limited diameter of the recovery solvent pipeline, solvent pressure, nozzle flow, etc. In an implementation case of this device, based on an RTO with an air volume of 50,000m3 / hr, the solvent flow rate in the vaporizer pipe is less than 40kg / hr, which is the rated maximum safe solvent volume of the system. After the RTO is turned on, if it is a printing line production, the RTO main fan frequency is generally 21HZ, and the exhaust air volume is about 25,000m3 / hr. At the same time, the RTO main fan is set to a minimum operating frequency of 12HZ and a minimum air volume of 15,000m3 / hr. According to this minimum air volume, calculations and actual verifications can completely volatilize 40kg / hr of solvent, and the original RTO design maximum exhaust gas inlet concentration (maximum inking volume product) is superimposed, which is still far below the LEL lower limit. Due to the different printing machine products, the concentration of existing printing exhaust is uncertain, but based on the limited and solidified order types of each printing factory, the superimposed exhaust gas concentration can be verified both theoretically and on-site. Theoretical verification is based on the total concentration of solvent in the exhaust gas of our maximum inking volume product + the maximum solvent volatility is lower than the safe lower limit of LEL. On-site verification is that the above production maximum concentration production exhaust gas, plus the above maximum volatility exhaust gas, after superimposed entering the RTO, the LEL system does not alarm and the RTO does not overheat alarm. In the RTO cigarette packaging gravure printing industry, only a very small fraction of waste gas can self-heat. This means that the waste gas from the highest inking volume is well below the LEL (Low Explosive Limit) limit, a widely accepted industry consensus. (Based on 50 kg / hr of ethyl acetate and an air volume of 20,000 m³ / hr, the LEL is calculated to be 3.18, well below the lower explosion limit and demonstrating reliable safety.) RTO still has enough volatile solvent to consume in the volatilization tank.

[0038] In the solvent recovery cleaning and disposal device, the arrangement of the observation window 9 and the cleaning port 10 on the box body 6, as well as the configuration of the feed pump 11 and the regulating valve 12 on the solvent pipeline 4, improve the operability and maintenance convenience of the device and the ability to control the flow of recovered solvent.

[0039] The guide member 13 is composed of a plurality of blades with adjustable angles. When the high-temperature exhaust gas enters the housing 6 from the air intake duct 2 through the guide member 13, the flow direction of the exhaust gas can be changed by adjusting the angle of the blades. The exhaust gas no longer passes directly through the volatilization box 3, but flows in a tortuous path within the housing 6, thereby increasing the distance traveled by the exhaust gas within the volatilization box 3 and thereby extending its residence time, creating more favorable conditions for sufficient heat exchange between the exhaust gas and the recovered solvent. The guide member 13 works in conjunction with the guide plate 7 and the atomizing nozzle 5 within the volatilization box 3 to jointly optimize the volatilization process of the recovered solvent. The high-temperature exhaust gas, whose flow direction has been changed and whose residence time has been extended by the guide member 13, fully contacts the recovered solvent droplets sprayed by the atomizing nozzle 5. Under the further guidance of the guide plate 7, the heat exchange process becomes more complete and efficient. For example, in some recovery solvent cleaning processes, the high-temperature exhaust gas adjusted by the guide member 13 enters the volatilization box 3 in a tortuous path, and encounters the droplets sprayed by the atomizing nozzle 5 multiple times at different heights and positions. Under the action of the guide plate 7, the droplets evaporate rapidly after sufficient heat exchange with the exhaust gas, thereby improving the volatilization efficiency and treatment quality of the recovery solvent.

[0040] The case 6 is tilted mainly to utilize the effect of gravity, so that the remaining unvolatile recovered solvent and possible impurities after volatilization under abnormal circumstances can naturally flow to the lower end of the case 6, which is convenient for centralized collection and discharge, and timely alarm is triggered to avoid accumulation in the case 6 and potential safety hazards. The drainage pipe 16 is set on the side of the case 6 close to the first leg 14, which is consistent with the tilt direction of the case 6. As the volatilization process of the recovered solvent in the case 6 proceeds, the unvolatile residual solvent will flow along the tilted case 6 toward the side of the first leg 14 due to gravity, and will be automatically discharged into the safety device through the drainage pipe 16, ensuring that no solvent will accumulate in the case 6 and maintaining the safe operation of the device. The guide cone is set at the diameter change of the solvent pipeline 4, mainly to optimize the flow state of the recovered solvent in the pipeline. When the recovered solvent flows from the part with larger diameter to the part with smaller diameter, the guide cone can guide the solvent to transition smoothly, avoiding problems such as fluid turbulence, pressure loss and local excessive or slow flow rate caused by sudden changes in pipe diameter, ensuring that the solvent is evenly and stably transported to subsequent processing links.

[0041] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure and are not limiting. Although the present disclosure has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present disclosure may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present disclosure, and all of these should be included in the scope of the claims of the present disclosure.

Claims

1. A recovery solvent cleaning and disposal device for cleaning the recovery solvent generated in the gravure printing process, characterized in that: include: A regenerative thermal oxidizer (1) is used for burning recovered solvent and performing harmless treatment on waste gas generated by the combustion, wherein the regenerative thermal oxidizer (1) is provided with an air inlet duct (2), and the air inlet duct (2) is used for passing high-temperature waste gas generated during the gravure printing process into the regenerative thermal oxidizer (1); A volatilization box (3) is arranged on the air inlet duct (2); The solvent pipeline (4) is connected to the volatilization box (3). The end of the solvent pipeline (4) is provided with a plurality of atomizing nozzles (5). The recovered solvent is sprayed out from the atomizing nozzles (5) and enters the volatilization box (3).

2. A solvent recovery cleaning and disposal device according to claim 1, characterized in that: The volatilization box (3) comprises: Box (6); A guide plate (7) is provided in the box body (6), and the guide plate (7) is used to guide the flow direction of the solvent droplets sprayed by the atomizing nozzle (5) so that the recovered solvent can be completely volatilized in the volatilization box (3).

3. A solvent recovery cleaning and disposal device according to claim 2, characterized in that: There are a plurality of guide plates (7), which are arranged in an array, and the atomizing nozzle (5) faces the guide plates (7).

4. A solvent recovery cleaning and disposal device according to claim 1, characterized in that: The solvent pipeline (4) has a preheating section (8), and the preheating section (8) is located in the air inlet duct (2). The preheating section (8) is used to absorb the heat of the high-temperature exhaust gas in the air inlet duct (2) to increase the temperature of the recovered solvent.

5. A solvent recovery cleaning and disposal device according to claim 2, characterized in that: The box body (6) is provided with an observation window (9) and a cleaning port (10), and the solvent recovery cleaning and disposal device further comprises: A feed pump (11) is provided on the solvent pipeline (4), and the feed pump (11) is used to provide power for the flow of the recovered solvent; A regulating valve (12) is provided on the solvent pipeline (4), and the regulating valve (12) is used to regulate the flow rate of the recovered solvent in the solvent pipeline (4).

6. A solvent recovery cleaning and disposal device according to claim 2, characterized in that: The box (6) also includes: The guide member (13) is connected to the box (6) through the guide member (13), and the guide member (13) is used to change the flow direction of the high-temperature exhaust gas in the air intake duct (2) so as to prolong the time that the high-temperature exhaust gas stays in the volatilization box (3).

7. A solvent recovery cleaning and disposal device according to claim 2, characterized in that: The box (6) is tilted and further comprises: A plurality of first legs (14) are provided on the box (6); There are a plurality of second legs (15) provided on the box body (6); the first legs (14) and the second legs (15) are used to support the box body (6).

8. A solvent recovery cleaning and disposal device according to claim 7, characterized in that: The first leg (14) is shorter than the second leg (15), the air inlet duct (2) is located on a side of the box body (6) close to the first leg (14), and further comprises: A liquid discharge pipeline (16) is provided on a side of the box body (6) close to the first leg (14), and the liquid discharge pipeline (16) is used to discharge the liquid recovery solvent accumulated in the box body (6) in an abnormal situation and to generate an alarm.

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