A method for recovering and utilizing CO2 back pressure gas in a filling machine

Abstract

This invention provides a method for recovering and utilizing CO2 back pressure gas from a filling machine, relating to the technical field of gas recovery. The method includes collecting CO2-containing gas generated during the filling process of the filling machine 1 into a cooling tank. The CO2-containing gas includes at least the gas extracted from the container to be filled by a liquid ring vacuum pump before filling, and the high-pressure back pressure gas discharged from the headspace of the container after filling. The cooling tank performs preliminary cooling on the collected CO2-containing gas to obtain a gas-liquid mixture. The cooling tank introduces the gas-liquid mixture into a gas-liquid separator through a pipeline. The cooling tank receives the gas and working fluid discharged by the liquid ring vacuum pump while simultaneously replenishing the working fluid. Through subsequent separation and purification processes, the waste gas is converted into qualified CO2 gas that can be reused in filling production, significantly reducing production costs and eliminating the safety risks caused by CO2 accumulation in a closed workshop.

Description

Technical Field

[0001] This invention relates to the technical field of gas recovery, and more specifically, to a method for recovering and utilizing CO2 back pressure gas from a filling machine. Background Technology

[0002] Isobaric filling is widely used in the production of carbonated liquid foods such as beer and beverages. Factories typically use CO2 as the back pressure gas. After the filling container is lifted and sealed, the filling valve opens the inlet channel, and CO2 gas from the filling cylinder is injected into the container. When the pressure inside the container equals the pressure inside the filling cylinder, the filling valve opens, and the material is injected into the container by gravity. For carbonated beverages, after filling and settling, because the pressure at the top of the container neck is much greater than atmospheric pressure, the filling valve needs to open the exhaust channel to release the back pressure gas at the top of the container neck to prevent foaming. For beer filling, because it is necessary to control the total oxygen content (TPO) after filling, a liquid ring vacuum pump is usually used to reduce the oxygen increase during filling. This is achieved by replacing the air inside the container with CO2 back pressure gas, thereby reducing the oxygen content. After vacuuming, the process is basically the same as for carbonated beverages: the valve opens after CO2 back pressure is applied, and after filling, the filling valve opens the exhaust channel to release the back pressure gas at the top of the container neck.

[0003] Whether it's carbonated beverage bottling or beer bottling, CO2 back pressure gas is released from the headspace after bottling. For high-capacity equipment, a large amount of this back pressure gas is released, resulting in resource waste. Secondly, for beer bottling, multiple vacuuming processes extract even more CO2 gas for direct emission, leading to even greater resource waste. Particularly for bottling equipment with a cleanroom, the released CO2 gas accumulates inside the cleanroom and cannot escape, causing CO2 levels to exceed safety standards and failing to meet production safety requirements. Summary of the Invention

[0004] The present invention aims to solve the problem of resource waste caused by the direct emission of CO2 back pressure gas during the existing isobaric filling process of gaseous liquid food, and the inability to achieve the recycling and reuse of CO2 resources.

[0005] To address the above problems, this invention provides a method for recovering and utilizing CO2 back pressure gas in a filling machine, comprising the following steps: S1: Collect the CO2-containing gas generated during the filling process of the filling machine into a cooling tank; wherein, the CO2-containing gas includes at least the gas extracted from the container to be filled by the liquid ring vacuum pump before filling, and the high-pressure back pressure gas discharged from the headspace of the container after filling. S2: The cooling tank performs preliminary cooling on the collected CO2-containing gas to obtain a gas-liquid mixture. The cooling tank introduces the gas-liquid mixture into the gas-liquid separator through a pipeline. The cooling tank is used to receive the gas and working fluid discharged from the liquid ring vacuum pump while replenishing the working fluid for it. S3: The gas-liquid separator separates the gas-liquid mixture to obtain a wet gas mainly composed of CO2; S4: The wet gas obtained from step S is pressurized by a blower and then transported to the CO2 treatment system for purification and upgrading to obtain CO2 gas that meets the filling requirements.

[0006] The present invention provides a method for recovering and utilizing CO2 back pressure gas in a filling machine, which, compared with the prior art, has the following beneficial effects, but is not limited to: CO2 is collected through vacuum exhaust and headspace back pressure exhaust after filling. Subsequent separation and purification processes convert the waste gas into qualified CO2 that can be reused in filling production, significantly reducing production costs and eliminating the safety risks caused by CO2 accumulation in the closed workshop. Secondly, during vacuuming, the friction between the compressed gas and liquid generates heat, resulting in a higher temperature of the discharged working fluid. The back pressure gas discharged from the headspace after filling is usually at a lower temperature, close to the ambient temperature or the temperature of the filling liquid. The cooling tank, as a shared container, allows these two to mix directly. The high-temperature liquid and low-temperature gas come into contact, and heat is naturally transferred from the liquid to the gas, achieving a cooling effect. This allows for the cascade utilization of energy internally. The cooling tank also replenishes the working fluid to the liquid ring vacuum pump, ensuring the stability of the vacuuming effect.

[0007] Furthermore, in step S1, the outlet of the liquid ring vacuum pump is connected to the inlet of the cooling tank through a pipe, and the extracted gas and part of the working fluid are discharged into the cooling tank together.

[0008] Furthermore, the high-pressure back pressure gas discharged from the headspace of the container is guided to the cooling tank through a separate pipeline.

[0009] Furthermore, a pneumatic butterfly valve is installed on the pipeline for the gas extracted from the container to be filled by the liquid ring vacuum pump before filling, and a pneumatic butterfly valve is installed on the pipeline for the high-pressure back pressure gas discharged from the top of the container after filling.

[0010] Furthermore, the outlet end of the cooling tank is provided with a first discharge pipe and a second discharge pipe; The inlet end of the first discharge pipe is connected to the upper gas phase space of the cooling tank for discharging gas components, and the inlet end of the second discharge pipe is connected to the lower liquid phase space of the cooling tank for discharging liquid components. The first discharge pipe and the second discharge pipe merge into a main pipe, which is connected to the inlet end of the gas-liquid separator.

[0011] Furthermore, a control valve is provided on the main pipeline for regulating or cutting off the flow rate of the gas-liquid mixture flowing into the gas-liquid separator.

[0012] Furthermore, the internal liquid level of the cooling tank is monitored by a level gauge to ensure the amount of liquid required for the liquid ring vacuum pump to form a stable liquid ring.

[0013] Furthermore, the gas-liquid separator is a vertical gravity separator or a cyclone separator, with a liquid discharge valve at its bottom, and the internal liquid level of the gas-liquid separator is controlled by a level gauge.

[0014] Furthermore, in step S3, the CO2 treatment system includes at least a filtration unit and a drying unit for removing particulate matter and moisture from the gas.

[0015] Furthermore, a liquid discharge valve is provided at the bottom of the cooling tank. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall process of the present invention.

[0017] Explanation of reference numerals in the attached figures: 1. Filling machine; 2. Cooling tank; 3. Liquid ring vacuum pump; 4. Gas-liquid separator; 5. CO2 treatment system; 6. Pneumatic butterfly valve one; 7. Pneumatic butterfly valve two; 8. Pneumatic butterfly valve three; 9. Pneumatic butterfly valve four. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings showing multiple embodiments according to this application. It should be understood that the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments described in this application without creative effort will fall within the scope of protection of this application.

[0019] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing specific embodiments only and is not intended to limit this application; the terms "comprising," "including," "having," "containing," etc., in the description, claims, and accompanying drawings of this application are open-ended terms. Therefore, "comprising," "including," or "having" refers to, for example, a method or apparatus having one or more steps or elements, but is not limited to having only these one or more elements. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0020] In the description of this invention, it should be understood that the terms "upper", "lower", "left", "right", "front", "rear", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0021] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0022] It should be emphasized that when the term "comprising / including" is used in this specification, it is used to explicitly indicate the presence of the stated feature, integer, step, or component, but does not exclude the presence or addition of one or more other features, integers, steps, parts, or groups of features, integers, steps, or parts.

[0023] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0024] See Figure 1 An embodiment of the present invention provides a method for recovering and utilizing CO2 back pressure gas in a filling machine, comprising: 1. A method for recovering and utilizing CO2 back pressure gas in a filling machine, characterized by comprising the following steps: S1: Collect the CO2-containing gas generated during the filling process of the filling machine 1 into the cooling tank 2; wherein, the CO2-containing gas includes at least the gas extracted from the container to be filled by the liquid ring vacuum pump 3 before filling, and the high-pressure back pressure gas discharged from the headspace of the container after filling. S2: Cooling tank 2 performs preliminary cooling on the collected CO2-containing gas to obtain a gas-liquid mixture. Cooling tank 2 introduces the gas-liquid mixture into gas-liquid separator 4 through a pipeline. Cooling tank 2 is used to receive the gas and working fluid discharged from liquid ring vacuum pump 3 and replenish it with working fluid at the same time. S3: Gas-liquid separator 4 separates the gas-liquid mixture to obtain a wet gas mainly composed of CO2; S4: The wet gas obtained in step S3 is pressurized by a blower and then transported to the CO2 treatment system 5 for purification and refining to obtain CO2 gas that meets the filling requirements.

[0025] In this embodiment, through the above steps, a complete closed-loop process from waste gas collection, preliminary treatment, deep separation, purification and reuse is constructed. The two originally dispersed CO2 waste gases are systematically recovered, and the cooling tank 2 is used as a hub to integrate the key functions of preliminary cooling of the gas, pressure buffering, and providing working fluid circulation replenishment for the liquid ring vacuum pump 3. This reduces production costs and eliminates the safety risks caused by CO2 accumulation in the closed workshop. Furthermore, the cooling tank, as a shared container, allows the two to mix directly. The high-temperature liquid and the low-temperature gas come into contact, and heat is naturally transferred from the liquid to the gas, achieving a cooling effect. This allows energy to be utilized in a cascade manner internally. The cooling tank also replenishes the working fluid to the liquid ring vacuum pump, ensuring the stability of the vacuuming effect.

[0026] Optionally, in step S1, the outlet of the liquid ring vacuum pump 3 is connected to the inlet of the cooling tank 2 through a pipe, and the extracted gas and part of the working fluid are discharged into the cooling tank 2 together.

[0027] In this embodiment, the exhaust gas from the liquid ring vacuum pump 3 is directly introduced into the cooling tank 2, which is the basis for realizing the circulation of the working fluid and internal energy exchange. This design allows the high-temperature working fluid to be collected and cooled in the cooling tank 2. At the same time, the compression heat energy it carries directly contacts and exchanges heat with the low-temperature CO2 gas from the back pressure exhaust gas in the cooling tank 2. This not only completes the cooling and regeneration of the working fluid, but also achieves the initial cooling of the recovered gas, which greatly improves the overall energy utilization efficiency of the system and reduces the operating energy consumption.

[0028] Optionally, the high-pressure back pressure gas discharged from the headspace of the container is guided to the cooling tank 2 through a separate pipeline.

[0029] In this embodiment, a recovery channel is set up for the headspace back pressure gas that is independent of the exhaust pipeline of the liquid ring vacuum pump 3. This ensures that the two gases do not interfere with each other before entering the cooling tank 2, and maintains the pressure and flow characteristics of their respective pipelines. After the high-pressure back pressure gas enters the cooling tank 2, its pressure is released and buffered, and its low-temperature characteristics become an important cold source in the cooling tank.

[0030] Optionally, a pneumatic butterfly valve 7 is provided on the pipeline through which the gas extracted from the container to be filled by the liquid ring vacuum pump 3 before filling, and a pneumatic butterfly valve 8 is provided on the pipeline through which the high-pressure back pressure gas discharged from the top of the container after filling.

[0031] In this embodiment, by setting pneumatic butterfly valve 7 and pneumatic butterfly valve 8, and interlocking their operation with the process cycle of the filling machine 1, the timing of the recovery of the two gas lines can be precisely controlled. Furthermore, both gas lines are branched off, and both branched-off pipes connect to a cleaning pipe. A pneumatic butterfly valve 9 is installed on the cleaning pipe to facilitate cleaning of the two gas lines. Before filling, a pneumatic butterfly valve 6 is installed between the branched-off pipe from which the gas extracted from the container to be filled by the liquid ring vacuum pump 3 and pneumatic butterfly valve 9. During vacuuming, pneumatic butterfly valve 6 is closed, and pneumatic butterfly valve 7 is open. When extracting high-pressure back-pressure gas, only pneumatic butterfly valve 8 is opened; when cleaning is required, pneumatic butterfly valve 9 is opened for cleaning.

[0032] Optionally, the outlet end of the cooling tank 2 is provided with a first discharge pipe and a second discharge pipe; The inlet end of the first discharge pipe is connected to the upper gas phase space of the cooling tank 2 for discharging gas components; the inlet end of the second discharge pipe is connected to the lower liquid phase space of the cooling tank 2 for discharging liquid components. The first discharge pipe and the second discharge pipe merge into a main pipe, which is connected to the inlet end of the gas-liquid separator 4.

[0033] In this embodiment, the first discharge pipe mainly discharges CO2-based gas, and the second discharge pipe mainly discharges settled working liquid. The two are remixed at the confluence to form a relatively uniform gas-liquid mixture. This is because the internal pressure of the liquid ring vacuum pump 3 is very high when compressing gas, which causes a large amount of CO2 gas to dissolve into the working liquid. The design of the branch confluence pipe is to avoid excessive liquid entrainment when pumping the gas phase or gas intake when pumping the liquid phase due to liquid level fluctuations in the cooling tank 2 during operation. This provides a more stable feed with a more stable flow rate and composition to the downstream gas-liquid separator 4, thereby improving the efficiency and effect of subsequent separation processes.

[0034] Optionally, a control valve is provided on the main pipeline for adjusting or cutting off the flow rate of the gas-liquid mixture flowing into the gas-liquid separator 4.

[0035] In this embodiment, the operator or the automatic control system can dynamically adjust the delivery rate of the gas-liquid mixture based on the processing capacity of the gas-liquid separator 4, the liquid level, or the load of the downstream purification unit.

[0036] Optionally, the internal liquid level of the cooling tank 2 is monitored by a level gauge to ensure that the amount of liquid required for the liquid ring vacuum pump 8 to form a stable liquid ring is maintained.

[0037] In this embodiment, the level gauge can accurately ensure that there is always a sufficient amount of working fluid in the cooling tank 2, so as to ensure that the liquid ring vacuum pump 3 will not be damaged by cavitation due to lack of fluid and maintain a stable vacuuming capacity.

[0038] Optionally, the gas-liquid separator 4 is a vertical gravity separator or a cyclone separator, with a liquid discharge valve at its bottom, and the internal liquid level of the gas-liquid separator 4 is controlled by a level gauge.

[0039] In this embodiment, both vertical gravity separators and cyclone separators can efficiently and thoroughly separate the liquid working fluid from the CO2 gas in the gas-liquid mixture, obtaining a wet gas with significantly reduced water content. Level gauge control ensures the stability of the liquid level within the gas-liquid separator 4.

[0040] Optionally, in step S3, the CO2 treatment system 5 includes at least a filtration unit and a drying unit for removing particulate matter and moisture from the gas.

[0041] In this embodiment, the filtration unit, such as a precision filter, is used to capture trace solid particles that may remain in the gas, protecting the cleanliness of downstream equipment and products; the drying unit, such as an adsorption dryer, is used to deeply remove water vapor from the gas.

[0042] Optionally, the cooling tank 2 is provided with a liquid discharge valve at the bottom.

[0043] In this embodiment, the liquid discharge valve at the bottom of the cooling tank 2 is used to completely empty the tank when the system is shut down for maintenance.

[0044] While the present invention has been disclosed above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and all such changes and modifications will fall within the scope of protection of the present invention.

Claims

1. A method for recovering and utilizing CO2 back pressure gas in a filling machine, characterized in that, Includes the following steps: S1: Collect the CO2-containing gas generated during the filling process of the filling machine 1 into the cooling tank (2); wherein the CO2-containing gas includes at least the gas extracted from the container to be filled by the liquid ring vacuum pump (3) before filling, and the high-pressure back pressure gas discharged from the top of the container after filling. S2: Cooling tank (2) performs preliminary cooling on the collected CO2-containing gas to obtain a gas-liquid mixture. Cooling tank (2) introduces the gas-liquid mixture into gas-liquid separator (4) through a pipeline. Cooling tank (2) is used to receive the gas and working fluid discharged from liquid ring vacuum pump (3) and replenish it with working fluid at the same time. S3: Gas-liquid separator (4) separates the gas-liquid mixture to obtain a wet gas mainly composed of CO2; S4: The wet gas obtained in step S3 is pressurized by a blower and then transported to the CO2 treatment system (5) for purification and refining to obtain CO2 gas that meets the filling requirements.

2. The method for recovering and utilizing CO2 back pressure gas in a filling machine according to claim 1, characterized in that, In step S1, the outlet of the liquid ring vacuum pump (3) is connected to the inlet of the cooling tank (2) through a pipe, and the extracted gas and part of the working fluid are discharged into the cooling tank (2).

3. The method for recovering and utilizing CO2 back pressure gas in a filling machine according to claim 2, characterized in that, The high-pressure back pressure gas discharged from the top of the container is guided to the cooling tank (2) through an independent pipeline.

4. The method for recovering and utilizing CO2 back pressure gas in a filling machine according to claim 3, characterized in that, Before filling, the pipeline for the gas extracted from the container to be filled by the liquid ring vacuum pump (3) is equipped with a pneumatic butterfly valve 2 (7), and the pipeline for the high-pressure back pressure gas discharged from the top of the container after filling is equipped with a pneumatic butterfly valve 3 (8).

5. The method for recovering and utilizing CO2 back pressure gas in a filling machine according to claim 1, characterized in that, The outlet end of the cooling tank (2) is provided with a first discharge pipe and a second discharge pipe; The inlet end of the first discharge pipe is connected to the upper gas phase space of the cooling tank (2) for discharging gas components, and the inlet end of the second discharge pipe is connected to the lower liquid phase space of the cooling tank (2) for discharging liquid components; the first discharge pipe and the second discharge pipe merge into a main pipe, which is connected to the inlet end of the gas-liquid separator (4).

6. A method for recovering and utilizing CO2 back pressure gas in a filling machine according to claim 5, characterized in that, The main pipeline is equipped with a control valve for regulating or cutting off the flow rate of the gas-liquid mixture flowing into the gas-liquid separator (4).

7. The method for recovering and utilizing CO2 back pressure gas in a filling machine according to claim 1, characterized in that, The internal liquid level of the cooling tank (2) is monitored by a level gauge to ensure that the amount of liquid required for the liquid ring vacuum pump (3) to form a stable liquid ring is maintained.

8. A method for recovering and utilizing CO2 back pressure gas in a filling machine according to claim 1, characterized in that, The gas-liquid separator (4) is a vertical gravity separator or a cyclone separator, and a liquid discharge valve is provided at its bottom. The internal liquid level of the gas-liquid separator (4) is controlled by a level gauge.

9. A method for recovering and utilizing CO2 back pressure gas in a filling machine according to claim 1, characterized in that, In step S3, the CO2 treatment system (5) includes at least a filtration unit and a drying unit for removing particulate matter and moisture from the gas.

10. A method for recovering and utilizing CO2 back pressure gas in a filling machine according to claim 1, characterized in that, The cooling tank (2) is equipped with a liquid discharge valve at the bottom.

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