A polyglycolic acid polymerization devolatilization system

Abstract

This invention relates to the field of polyglycolic acid (PGA) synthesis technology, and more particularly to a PGA polymerization devolatilization system, comprising a steam jet vacuum system, a mixing condenser, a liquid ring pump, and a utility system. The steam jet vacuum system is connected at its inlet to the PGA polymerization reaction system and at its outlet to the mixing condenser inlet, used to separate unreacted monomers and low-molecular-weight byproducts and other volatiles. The mixing condenser gas outlet is connected to the liquid ring pump inlet, where condensable components are liquefied through condensation, and non-condensable gases are discharged. The liquid ring pump extracts non-condensable gases to maintain the system vacuum. The utility system integrates power steam pipelines, condensing medium pipelines, and insulation medium pipelines, providing power, condensation, and insulation support for each component. Through multi-stage jet compression, spray condensation, and insulation synergistic operation, the system improves mass transfer efficiency and process control precision, effectively removes volatiles, and enhances the purity, biodegradability, and mechanical properties of the PGA product.

Description

Technical Field

[0001] This invention relates to the field of polyglycolic acid synthesis technology, and more particularly to a polyglycolic acid polymerization devolatilization system. Background Technology

[0002] In the synthesis of polyglycolic acid (PGA), a biodegradable polymer, monomers form polymer chains through polymerization reactions. However, unreacted monomers, solvents, or low-molecular-weight byproducts and other volatile components often remain in the reaction system, affecting the purity and performance of the polymer. Deviation technology, as a key step in the post-processing, uses methods such as depressurization, heating, or inert gas replacement to separate components based on their volatility differences, effectively reducing impurity content and thus improving the thermal stability and processing applicability of PGA to meet the requirements of biomedical or environmentally friendly applications.

[0003] Existing polyglycolic acid (PGA) polymerization devolatilization technologies suffer from the following technical challenges: Firstly, existing devolatilization systems have limited mass transfer efficiency when handling high-viscosity PGA melts, making it difficult to effectively remove small-molecule residues. Secondly, insufficient process control precision leads to significant fluctuations in key parameters such as temperature, pressure, and material residence time in the later stages of the polymerization reaction. For example, in the preparation of medical-grade PGA sutures or biodegradable packaging films, excessively high residual monomer content directly causes a decrease in product thermal stability, manifesting as easy thermal degradation during processing, a broadened molecular weight distribution, and ultimately affecting the material's mechanical strength and controllable degradation cycle. This fails to meet the stringent requirements for consistency and reliability in high-end biomedical materials or high-standard environmentally friendly materials. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a polyglycolic acid polymerization devolatilization system, which solves the technical problem that the low mass transfer efficiency and poor process control of existing devolatilization systems result in high residual monomer content in polyglycolic acid products, affecting product purity, biodegradability, and mechanical properties.

[0005] To solve the above-mentioned technical problems, the specific contents of the present invention are as follows: The present invention provides a polyglycolic acid polymerization devolatilization system, comprising: The inlet of the steam jet vacuum system is used to connect to the polyglycolic acid polymerization reaction system, and the outlet of the steam jet vacuum system is connected to the inlet of the mixing condenser. The steam jet vacuum system separates volatiles, including unreacted monomers and low-molecular-weight byproducts, from the polyglycolic acid polymerization reaction system and delivers the volatiles to the mixing condenser. The gas outlet of the mixing condenser is connected to the inlet of the liquid ring pump. The mixing condenser receives and condenses the volatiles, converting the condensable components into a liquid state, and allowing the non-condensable gases to be discharged from the gas outlet. The liquid ring pump draws non-condensable gas from the mixing condenser to establish and maintain a vacuum in the mixing condenser and the steam jet vacuum system; The utility system includes a power steam pipeline, a condensing medium pipeline, and an insulation medium pipeline; the power steam pipeline is connected to the steam jet vacuum system to provide power steam for the steam jet vacuum system; the condensing medium pipeline is connected to the mixing condenser to provide condensing medium for the mixing condenser; and the insulation medium pipeline is laid on the outer wall of the system pipeline to insulate the system pipeline.

[0006] Furthermore, in the polyglycolic acid polymerization devolatilization system of the present invention, the vapor jet vacuum system includes a multi-stage ejector, with the outlet of the previous stage ejector connected to the inlet of the next stage ejector, so that the gas is compressed and transported stage by stage.

[0007] Furthermore, in the polyglycolic acid polymerization devolatilization system of the present invention, the power steam pipeline is connected to each stage of the multi-stage ejector.

[0008] Furthermore, in the polyglycolic acid polymerization devolatilization system of the present invention, a spraying device is provided inside the mixing condenser, and the condensing medium pipeline is connected to the spraying device, which sprays the condensing medium into the mixing condenser.

[0009] Furthermore, in the polyglycolic acid polymerization devolatilization system of the present invention, the heat-insulating medium pipeline is wrapped or covered on the outer wall of the material pipeline from the outlet of the polyglycolic acid polymerization reaction system to the inlet of the mixing condenser.

[0010] Furthermore, in the polyglycolic acid polymerization devolatilization system of the present invention, the temperature of the heat medium flowing in the insulation medium pipeline is higher than the freezing point of the condensable component in the volatiles flowing in the material pipeline.

[0011] Furthermore, in the polyglycolic acid polymerization devolatilization system of the present invention, the suction pressure of the steam jet vacuum system is less than 1 kPa; the difference between the exhaust gas pressure at the outlet of the mixing condenser and the suction pressure of the steam jet vacuum system is a positive value.

[0012] Furthermore, in the polyglycolic acid polymerization devolatilization system of the present invention, the inlet of the liquid ring pump is directly connected to the gas outlet of the mixing condenser, and the outlet of the liquid ring pump is connected to the atmosphere or a subsequent exhaust gas treatment system.

[0013] Furthermore, in the polyglycolic acid polymerization devolatilization system of the present invention, the bottom of the mixing condenser is provided with a drain port, which is connected to a liquid component collection device or a recovery system.

[0014] Furthermore, in the polyglycolic acid polymerization devolatilization system of the present invention, the process of the polyglycolic acid polymerization reaction system delivering volatiles to the steam jet vacuum system is carried out simultaneously with the process of the liquid ring pump maintaining the system vacuum.

[0015] Beneficial effects of this invention; The polyglycolic acid (PGA) polymerization devolatilization system provided by this invention establishes a high vacuum environment through a multi-stage jet vacuum system using a steam jet vacuum system to progressively compress gas, promoting the efficient separation of unreacted monomers and low-molecular-weight byproducts from the polymerization system. A spray device is installed inside the mixing condenser to accelerate the liquefaction and recovery of condensable components by uniformly dispersing the condensing medium. A liquid ring pump is directly connected to the gas outlet of the mixing condenser to continuously extract non-condensable gases to maintain the system's vacuum stability. The utility system integrates power steam pipelines, condensing medium pipelines, and insulation medium pipelines, providing power, condensation, and insulation support for the devolatilization process. All components work collaboratively based on fluid dynamics and thermodynamics principles, improving mass transfer efficiency and process control precision, reducing the residual monomer content in the PGA product, thereby optimizing polymer purity, biodegradability, and mechanical properties. Simultaneously, the system operates stably with reduced energy consumption, making it suitable for large-scale production of high-end applications such as medical-grade sutures and biodegradable packaging films. Attached Figure Description

[0016] To more clearly illustrate the technical solution of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on the drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the system architecture of a polyglycolic acid polymerization devolatilization system according to the present invention.

[0018] Figure 2 This is a schematic diagram of the actual application system structure of the polyglycolic acid polymerization devolatilization system of the present invention. Detailed Implementation

[0019] To make the technical solution of the present invention clearer, the present invention will be clearly and completely described below with reference to specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. The present invention provided by various embodiments will be described in detail below with reference to the accompanying drawings. To better understand the purpose of the present invention, the present invention will be described in further detail below.

[0020] Please see Figure 1 as well as Figure 2The present invention provides a polyglycolic acid polymerization devolatilization system, comprising: The inlet of the steam jet vacuum system is used to connect to the polyglycolic acid polymerization reaction system, and the outlet of the steam jet vacuum system is connected to the inlet of the mixing condenser. The steam jet vacuum system separates volatiles, including unreacted monomers and low-molecular-weight byproducts, from the polyglycolic acid polymerization reaction system and delivers the volatiles to the mixing condenser. The gas outlet of the mixing condenser is connected to the inlet of the liquid ring pump. The mixing condenser receives and condenses the volatiles, converting the condensable components into a liquid state, and allowing the non-condensable gases to be discharged from the gas outlet. The liquid ring pump draws non-condensable gas from the mixing condenser to establish and maintain a vacuum in the mixing condenser and the steam jet vacuum system; The utility system includes a power steam pipeline, a condensing medium pipeline, and an insulation medium pipeline; the power steam pipeline is connected to the steam jet vacuum system to provide power steam for the steam jet vacuum system; the condensing medium pipeline is connected to the mixing condenser to provide condensing medium for the mixing condenser; and the insulation medium pipeline is laid on the outer wall of the system pipeline to insulate the system pipeline.

[0021] The polyglycolic acid (PGA) polymerization devolatilization system achieves efficient devolatilization by integrating multiple functional modules. The steam jet vacuum system serves as the initial stage, with its inlet connected to the PGA polymerization reaction system. It utilizes vacuum suction to separate unreacted monomers and low-molecular-weight byproducts from the high-viscosity melt. The steam jet vacuum system typically employs a multi-stage ejector structure, with the outlet of the previous stage ejector connected in series with the inlet of the next stage ejector. By progressively compressing the vacuum level, the mass transfer efficiency is enhanced. This design is suitable for handling easily condensable components generated during PGA polymerization, preventing incomplete devolatilization due to pressure fluctuations. After being extracted, the volatiles are transported through the outlet to a mixing condenser, completing the initial stage of gas-liquid separation.

[0022] The mixing condenser receives volatiles from the vapor jet vacuum system and evenly disperses the condensing medium through an internal spray device, causing condensable components such as oligomers or methanol to rapidly condense into a liquid state. The gas outlet of the mixing condenser is directly connected to a liquid ring pump. Non-condensable gases, including nitrogen or oxygen, are discharged from the gas outlet after condensation, while the liquid components are introduced into the recovery system through the bottom drain port. This condensation method achieves efficient separation based on the difference in volatility between components, reducing the impact of residues on polymer purity. The liquid ring pump continuously extracts non-condensable gases, maintaining a stable vacuum environment in the mixing condenser and vapor jet vacuum system, preventing interruptions in the devolatilization process due to pressure rise and ensuring its continuity.

[0023] The utilities system supports the devolatilization system. Power steam pipelines supply power steam to the steam jet vacuum system, driving the multi-stage ejectors. Condensate pipelines supply condensate to the mixing condenser, enhancing heat exchange through spraying. Insulation media pipelines are wrapped around the outer walls of the system piping, ensuring the temperature of the flowing heat medium is higher than the freezing point of the condensable components in the volatiles, preventing condensation and blockage during transport. For example, in the production of medical-grade polyglycolic acid, the insulation design avoids scaling in pipelines due to low temperatures, improving system reliability. All components work collaboratively: the steam jet vacuum system establishes a high vacuum environment, the mixing condenser recovers condensate, and the liquid ring pump maintains vacuum balance, forming a closed-loop devolatilization process that effectively improves the thermal stability and mechanical properties of the polyglycolic acid product.

[0024] Specifically, the polyglycolic acid polymerization devolatilization system of the present invention includes a multi-stage ejector system, wherein the outlet of the previous stage ejector is connected to the inlet of the next stage ejector, so that the gas is compressed and transported stage by stage.

[0025] In the polyglycolic acid (PGA) polymerization devolatilization system, a multi-stage ejector design is employed in the vapor jet vacuum system to enhance vacuum efficiency. In this multi-stage ejector configuration, the outlet of the preceding ejector is directly connected to the inlet of the following ejector, forming a series structure. This connection facilitates continuous gas flow. After being drawn into the PGA polymerization reaction system, the gas first enters the first-stage ejector, where it is initially compressed under the drive of motive steam. Subsequently, it undergoes progressive compression through each subsequent ejector stage. This staged compression process gradually reduces the gas pressure, thereby establishing a high vacuum environment within the system, which is beneficial for the effective separation of volatiles.

[0026] The multi-stage ejector's progressive compression mechanism is based on the jet principle. Each ejector uses motive steam to generate a high-speed airflow, drawing in and compressing the gas from the previous stage. This design distributes the compression load, with the earlier stage handling relatively high-pressure gases and the later stage focusing on lower pressure ranges, reducing the burden on single-stage equipment. In polyglycolic acid production scenarios, such as the preparation of medical-grade biodegradable materials, unreacted monomers and low-molecular-weight byproducts in high-viscosity melts need to be stably removed. The multi-stage ejector avoids pressure surges through progressive compression, improving mass transfer efficiency.

[0027] After multi-stage compression, the gas is delivered from the outlet of the steam jet vacuum system to the mixing condenser, where the volatiles are condensed and recovered. The integration of the steam jet vacuum system and the mixing condenser ensures the continuity of the devolatilization process. The mixing condenser converts condensable components into liquid by spraying a condensing medium, while non-condensable gases are drawn by a liquid ring pump to maintain vacuum balance. The series structure of the multi-stage ejectors not only optimizes vacuum control but also reduces energy loss, resulting in high reliability of the polyglycolic acid polymerization devolatilization system during long-term operation.

[0028] Specifically, in the polyglycolic acid polymerization devolatilization system of the present invention, the power steam pipeline is connected to each stage of the multi-stage ejector.

[0029] In the polyglycolic acid polymerization devolatilization system, a steam jet vacuum system establishes a high vacuum environment by performing staged gas compression through multi-stage ejectors. The power steam line, a key component of the utility system, is responsible for supplying power steam to each stage of the multi-stage ejectors. This connection method allows each ejector to receive an independent steam supply, supporting the continuity of the gas compression process.

[0030] The power steam pipeline is designed with a branch network, extending multiple branch pipes from the main steam source. Each branch pipe connects directly to the steam inlet of the first-stage ejector. Control valves are installed at the connection points to regulate the steam flow and pressure parameters, adapting to the compression requirements of different stages in the multi-stage ejector. For example, in the polyglycolic acid polymerization process, the pre-ejector handles the initial low-vacuum gas and requires higher steam pressure to drive it; the post-ejector handles the partially compressed gas and requires fine-tuning of the steam to maintain a stable high vacuum.

[0031] The sequential operation of multi-stage ejectors relies on the uniform steam distribution in the power steam pipeline. Steam flows from the pipeline into each stage ejector, driving the gas compression action; the outlet gas of the previous stage ejector is delivered to the inlet of the next stage, while the steam supply remains synchronized, avoiding vacuum fluctuations caused by steam interruptions or uneven pressure. This logic improves the coordination of the devolatilization system and enhances mass transfer efficiency.

[0032] In practice, the design of the power steam pipeline connection takes into account the high-viscosity material characteristics of polyglycolic acid production. For example, when preparing biodegradable packaging films, monitoring steam parameters and adjusting valves in a timely manner can prevent the injector from becoming inefficient due to insufficient steam. This arrangement also reduces heat loss, ensuring the stability of the devolatilization process at high temperatures, thereby supporting the improvement of polymer purity.

[0033] Specifically, in the polyglycolic acid polymerization devolatilization system of the present invention, a spraying device is provided inside the mixing condenser, and the condensing medium pipeline is connected to the spraying device, which sprays the condensing medium into the mixing condenser.

[0034] The spray system inside the hybrid condenser employs an array of nozzles, with each nozzle evenly distributed on the upper part or sidewalls of the condenser cavity to achieve broad coverage of the condensing medium. The spray system is connected to the condensing medium pipeline via a porous distribution plate or annular pipe, allowing the condensing medium to be uniformly sprayed out in the form of fine droplets. This structural design is based on the principle of increasing the gas-liquid contact area. During the devolatilization process of polyglycolic acid polymerization, when volatiles containing unreacted monomers and low-molecular-weight byproducts enter the hybrid condenser, the spray system disperses the condensing medium, promoting sufficient interaction between the condensable components and the refrigerant, thereby accelerating the condensation conversion. For example, in the preparation of biodegradable packaging materials, the uniform distribution of the spray system helps avoid localized overheating or incomplete condensation, improving devolatilization efficiency.

[0035] The condensate piping is made of corrosion-resistant materials, such as stainless steel, and connects directly to the inlet of the spray unit via flanges. The condensate flowing through the piping, such as an aqueous solution of ethylene glycol or a specialized refrigerant, is maintained at a constant flow rate and pressure via a pumping system. Upon receiving the condensate, the spray unit uses a built-in pressurization mechanism to atomize it into micron-sized droplets, which are then sprayed into the high-temperature gas stream of the mixing condenser. This process is based on forced convection heat transfer; after the droplets are thoroughly mixed with the gas, they rapidly absorb heat, lowering the gas temperature and causing condensable components such as oligomers and methanol to condense into a liquid state. During system operation, operators control the medium flow rate by adjusting the piping valves to match changes in volatile load and maintain condensation stability.

[0036] In practical polyglycolic acid (PGA) production scenarios, the operational details of the spray system focus on preventing clogging and optimizing energy efficiency. For example, in the production of medical-grade sutures, high-viscosity oligomers in the volatiles tend to deposit on the condenser walls. The spray system continuously rinses the surface, reducing the risk of fouling. The selection of the condensing medium considers freezing point compatibility; for example, using a high-boiling-point refrigerant avoids freezing. The spray process works in conjunction with the steam jet vacuum system and the liquid ring pump to form a closed-loop control. Logically, the volatiles are first extracted by vacuum, then separated by spray condensation, and finally the vacuum is maintained by the liquid ring pump, ensuring a continuous devolatilization process. This design improves the purity and thermal stability of the PGA product and is suitable for large-scale continuous production.

[0037] Specifically, in the polyglycolic acid polymerization devolatilization system of the present invention, the heat-insulating medium pipeline is wrapped or covered on the outer wall of the material pipeline from the outlet of the polyglycolic acid polymerization reaction system to the inlet of the mixing condenser.

[0038] The insulating medium is wound or wrapped around the outer wall of the material pipeline from the outlet of the polyglycolic acid polymerization reaction system to the inlet of the mixing condenser. This design maintains the internal temperature of the material pipeline through an external heat source, preventing condensation of volatiles during transportation. In the polyglycolic acid polymerization devolatilization system, volatiles include unreacted monomers and low-molecular-weight byproducts. These components are prone to condensation at low temperatures, leading to pipeline blockage or decreased mass transfer efficiency. The insulating medium is wound or wrapped, for example, in a spiral wound manner, to ensure uniform distribution of the heat transfer medium along the surface of the material pipeline, forming a continuous insulation layer. The wound structure is based on the principle of heat conduction, reducing heat loss and keeping the volatiles in a gaseous state, facilitating subsequent condensation.

[0039] In practical implementation, flexible metal pipes or specialized insulation tapes can be used for the insulation medium pipeline, with the winding spacing dynamically adjusted according to the heat medium flow rate and the condensation point of the volatiles. In polyglycolic acid production scenarios, such as the preparation of medical-grade sutures, where the material pipeline transports high-viscosity melt derivatives over long distances, spiral winding provides stable heat exchange and avoids localized overcooling. The covering method involves wrapping the material pipeline with multiple layers of insulation material, with an outer protective cover to enhance insulation and prevent mechanical damage. The vapor-phase heat medium flows within the insulation medium pipeline, and its temperature is always higher than the condensable components in the volatiles, such as the condensation temperature of oligomers or methanol. Real-time monitoring using temperature sensors enables precise temperature control.

[0040] The insulation system logically serves the continuity of the devolatilization process. Material pipelines connect the steam jet vacuum system and the mixing condenser. The insulation design ensures that volatiles extracted from the reaction system do not condense due to temperature loss and directly enter the mixing condenser for gas-liquid separation. In actual operation, the insulation media pipelines must have access ports for maintenance to facilitate regular cleaning of scale buildup, adapting to the long-term operational needs of large-scale polyglycolic acid production. This arrangement improves system reliability, reduces downtime due to blockages, and optimizes energy efficiency.

[0041] Temperature management in insulation media pipelines combines thermodynamic and fluid mechanics principles. The heat medium circulation system maintains a constant flow rate through pumping, ensuring uniform temperature on the outer wall of the material pipeline. For example, in the production of biodegradable packaging materials, insulation media pipelines work in conjunction with power steam pipelines to prevent volatiles from cooling rapidly in a vacuum environment. The winding or covering structure also considers the matching of thermal expansion coefficients, selecting compatible materials to avoid thermal stress cracking and extend equipment life.

[0042] Specifically, in the polyglycolic acid polymerization devolatilization system of the present invention, the temperature of the heat medium flowing in the insulation medium pipeline is higher than the freezing point of the condensable component in the volatiles flowing in the material pipeline.

[0043] Insulating media are wound or wrapped around the outer wall of the material pipeline between the outlet of the polyglycolic acid polymerization reaction system and the inlet of the mixing condenser, maintaining the internal temperature stability of the material pipeline through an external heat source. During the polyglycolic acid polymerization devolatilization process, volatiles include unreacted monomers and low-molecular-weight byproducts. These components are prone to condensation due to temperature drops during transport, leading to pipeline blockage or reduced mass transfer efficiency. The design of the insulating media pipeline is based on the principle of heat conduction, employing spiral winding or multi-layer wrapping to ensure uniform distribution of the heat medium along the surface of the material pipeline, forming a continuous insulation layer. For example, in the production of medical-grade polyglycolic acid sutures, long-distance material pipelines transport high-viscosity melt derivatives; the insulation structure prevents localized overcooling, ensuring that the volatiles enter the subsequent condensation unit in a gaseous state.

[0044] Temperature control of the heat transfer medium is a crucial aspect of the insulation system. The temperature of the heat transfer medium flowing through the insulation medium pipeline must always be higher than the freezing point of the condensable components in the volatiles flowing through the material pipeline. The technical solution involves the configuration of the heat transfer medium circulation system, including the heat transfer medium source, pumping unit, and temperature control device. A vapor-phase medium, such as a specialized heat transfer oil, is selected as the heat transfer medium, whose boiling point matches the freezing point of the volatiles, and a constant flow rate is maintained by a circulation pump. Temperature sensors monitor the temperature of the outer wall of the material pipeline in real time, feeding back to the control valve to dynamically adjust the heat transfer medium input and avoid overheating or underheating. In the scenario of biodegradable packaging film preparation, heat transfer medium temperature management, combined with the characteristics of the volatile components, requires the heat transfer medium to have a wide temperature range adaptability due to the difference in freezing points between oligomers and methanol, preventing condensation and accumulation caused by temperature fluctuations.

[0045] The integration logic of the insulation medium pipeline and the material pipeline is based on thermodynamic equilibrium, with the insulation operation serving the continuity of the devolatilization process. The setting of the heat medium temperature above its freezing point ensures that the volatiles extracted from the reaction system do not undergo phase change due to environmental heat loss and are directly transported to the mixing condenser for gas-liquid separation. The flow state of the volatiles within the material pipeline depends on the external insulation, and the heat exchange efficiency of the insulation medium pipeline affects the overall devolatilization rate. In actual operation, the installation of inspection ports facilitates regular cleaning of scale buildup, adapting to the long-term operational needs of large-scale polyglycolic acid production. This arrangement improves system reliability, reduces downtime, and optimizes energy utilization.

[0046] The implementation details of the insulation system include material compatibility and structural optimization. High-temperature resistant flexible metal tubing is used for the insulation medium pipeline, and the winding spacing is dynamically calculated based on the heat capacity of the heat medium and the thermal conductivity of the volatiles. The heat medium circulation system works in conjunction with the power steam pipeline; for example, in a high-temperature vacuum environment, the insulation design prevents rapid cooling of the volatiles, maintaining the intake efficiency of the steam jet vacuum system. The insulation step precedes the condensation stage, providing stable intake conditions for the mixing condenser and enhancing the devolatilization effect. In the polyglycolic acid polymerization devolatilization system, temperature management of the insulation medium pipeline is fundamental to mass transfer optimization, supporting improvements in product purity and thermal stability.

[0047] Specifically, in the polyglycolic acid polymerization devolatilization system of the present invention, the suction pressure of the steam jet vacuum system is less than 1 kPa; the difference between the exhaust gas pressure at the outlet of the mixing condenser and the suction pressure of the steam jet vacuum system is positive.

[0048] In polyglycolic acid (PGA) polymerization devolatilization systems, the suction pressure of the vapor jet vacuum system is set below a specific threshold. This parameter is chosen based on the promoting effect of a high vacuum environment on the separation efficiency of volatiles. Lowering the suction pressure helps enhance the ability to extract unreacted monomers and low-molecular-weight byproducts from the PGA polymerization reaction system, reducing the impact of residues on polymer purity. For example, in the production of medical-grade PGA sutures, a high vacuum setting can effectively remove easily condensable components from high-viscosity melts, avoiding incomplete devolatilization due to excessive pressure.

[0049] The steam jet vacuum system achieves staged gas compression through a series of multi-stage ejectors, thereby establishing and maintaining a low intake pressure. In the multi-stage ejector system, the outlet of the previous stage ejector is directly connected to the inlet of the next stage ejector. The gas is progressively compressed under the drive of motive steam, dispersing the load on individual stages. This design logic serves the stability of the vacuum level, preventing pressure fluctuations from affecting the mass transfer process. The mixing condenser receives volatiles from the steam jet vacuum system, and its internal spray device uniformly disperses the condensate medium, accelerating the liquefaction of condensable components.

[0050] The pressure difference between the exhaust gas at the outlet of the mixing condenser and the intake pressure of the steam jet vacuum system remains positive. This pressure gradient ensures that the gas flow direction is unidirectional, from the vacuum system to the condenser, avoiding operational interruptions caused by backflow. Based on fluid dynamics principles, this positive pressure differential allows non-condensable gases to smoothly enter the liquid ring pump for subsequent processing. In practical operations, such as in the preparation of biodegradable packaging films, the pressure difference is monitored in real-time via sensors, dynamically adjusting the operating parameters of the steam jet vacuum system and the mixing condenser to maintain system balance.

[0051] The integrated insulation system features insulation medium piping wrapped around the outer wall of the material piping, ensuring the heat medium temperature is higher than the condensation point of the volatiles and preventing condensation blockage during transport. The synergistic operation of the steam jet vacuum system and the mixing condenser is based on thermodynamics and mass transfer optimization. The multi-stage jetting reduces energy loss through progressive compression, while spray condensation enhances heat exchange efficiency. The overall logic chain of the polyglycolic acid polymerization devolatilization system begins with vacuum extraction, proceeds through condensation and separation, and finally maintains a closed-loop vacuum using a liquid ring pump, improving the product's thermal stability and mechanical properties.

[0052] Specifically, in the polyglycolic acid polymerization devolatilization system of the present invention, the inlet of the liquid ring pump is directly connected to the gas outlet of the mixing condenser, and the outlet of the liquid ring pump is connected to the atmosphere or a subsequent exhaust gas treatment system.

[0053] The liquid ring pump inlet is directly connected to the gas outlet of the mixing condenser. This arrangement, based on fluid dynamics principles, aims to minimize airflow resistance and pressure loss. In the polyglycolic acid polymerization devolatilization system, non-condensable gases, after being discharged from the mixing condenser, are directly introduced into the liquid ring pump through a short-distance pipe or flange interface, avoiding the use of complex bends or intermediate equipment, thereby maintaining the continuity of gas flow. For example, in the production process of medical-grade polyglycolic acid sutures, direct connection supports rapid gas transfer, prevents vacuum fluctuations caused by pipeline detours, and improves devolatilization efficiency.

[0054] The outlet of the liquid ring pump is connected to the atmosphere or a subsequent exhaust gas treatment system, the choice depending on environmental compliance and process optimization requirements. When the exhaust gas components are mainly inert gases and pose no pollution risk, it can be directly discharged into the atmosphere; if the exhaust gas contains non-condensable low-molecular-weight byproducts, it is connected to a recovery unit for purification or resource recovery. In the scenario of biodegradable packaging film preparation, the outlet connection design considers the recycling of waste gas, recovering components such as methanol through a subsequent treatment system, reducing production costs and meeting environmental standards.

[0055] The direct connection between the liquid ring pump and the mixing condenser logically serves the stability of the vacuum maintenance mechanism. After the mixing condenser liquefies the condensable components, the non-condensable gases are continuously drawn in by the liquid ring pump, forming a pressure gradient that supports the balance of the devolatilization system. The operation of the liquid ring pump works in conjunction with the vapor jet vacuum system. For example, in high-temperature, high-vacuum environments, the pumping action of the liquid ring pump compensates for the gas volume changes during the condensation process, preventing backflow or blockage. In practice, corrosion-resistant materials are used to fabricate the connecting pipes, and regular sealing tests are conducted to reduce the risk of leakage and enhance system durability.

[0056] The application details of the polyglycolic acid (PGA) polymerization devolatilization system are reflected in the integrated design of the liquid ring pump connection. The liquid ring pump inlet directly receives the gas discharged from the mixing condenser, and the outlet is flexibly configured according to the characteristics of the exhaust gas. This arrangement adapts to the needs of large-scale continuous production. On medical material production lines, the coordinated operation of the liquid ring pump and the exhaust gas treatment system is based on real-time monitoring data, dynamically adjusting the extraction rate to match changes in volatile load. The optimized connection scheme reduces energy loss and improves the purity and thermal stability of the PGA product.

[0057] Specifically, in the polyglycolic acid polymerization devolatilization system of the present invention, the bottom of the mixing condenser is provided with a drain port, which is connected to a liquid component collection device or a recovery system.

[0058] The drain port at the bottom of the mixing condenser uses a flange connection for easy and sealed connection with external piping systems, avoiding the risk of leakage. Located at the lowest point of the mixing condenser shell, the drain port utilizes gravity to promote the natural accumulation and complete discharge of condensed liquid components. During the polyglycolic acid polymerization devolatilization process, volatiles are drawn into the mixing condenser via a steam jet vacuum system. An internal spray device disperses the condensing medium into droplets, accelerating the liquefaction of condensable components such as oligomers and methanol. The liquid material accumulates at the bottom of the condenser and is guided to subsequent processing units through the drain port. This arrangement is based on fluid dynamics principles, supports continuous operation, and reduces the decrease in mass transfer efficiency caused by residual liquid accumulation.

[0059] The drain outlet connects to a liquid component collection device or recovery system, with the connecting pipes made of corrosion-resistant stainless steel to withstand the acidic or high-temperature environment in polyglycolic acid (PGA) production. The collection device is typically a buffer tank, providing temporary storage capacity to balance fluctuating flow rates of the liquid components. The recovery system may integrate distillation or separation modules to extract valuable components such as unreacted monomers, enabling resource reuse. In the production of medical-grade PGA sutures, the tight connection between the drain outlet and the collection device prevents oligomers from clogging the pipeline, maintaining system stability. Cleaning interfaces are pre-installed in the pipeline for regular removal of scale, accommodating the maintenance needs of large-scale production.

[0060] The operation of the drain port is coordinated with the condensation efficiency of the mixing condenser. The steam jet vacuum system maintains a high vacuum environment to extract volatiles, while the mixing condenser liquefies condensable components through heat exchange. After the liquid material is discharged through the drain port, the non-condensable gases enter the liquid ring pump to maintain vacuum balance. This process design ensures the continuity of the devolatilization process. The discharge action of the drain port is linked to the liquid level monitoring inside the condenser to prevent liquid from entering the gas outlet and affecting the performance of the liquid ring pump. In the production of biodegradable polyglycolic acid packaging materials, the reliable operation of the drain port reduces quality fluctuations caused by interruptions and improves product purity.

[0061] In practical applications, the configuration of the drain outlet takes into account both operational convenience and safety. For example, sight glasses or sensors are used to monitor the liquid level, and manual or automatic valves control the discharge rhythm. The insulation system maintains the temperature around the drain outlet through the heat transfer medium pipeline, preventing the liquid components from condensing and solidifying during transport. Integration of the utility system supports energy efficiency optimization of the devolatilization process. By refining the technical solutions for the drain outlet, those skilled in the art can understand the causal relationships between the steps, thereby achieving efficient devolatilization in practice.

[0062] Specifically, in the polyglycolic acid polymerization devolatilization system of the present invention, the process of the polyglycolic acid polymerization reaction system delivering volatiles to the steam jet vacuum system is carried out simultaneously with the process of the liquid ring pump maintaining the system vacuum.

[0063] In the polyglycolic acid (PGA) polymerization devolatilization system, the process of the PGA polymerization reaction system supplying volatiles to the vapor jet vacuum system occurs simultaneously with the process of the liquid ring pump maintaining the system vacuum. This synchronous operation is based on the requirements of continuous production, improving devolatilization efficiency by coordinating volatile separation and vacuum environment stability in real time. During system operation, volatiles generated by the polymerization reaction system, including unreacted monomers and low-molecular-weight byproducts, are continuously extracted and introduced into the vapor jet vacuum system; at the same time, the liquid ring pump operates continuously, extracting non-condensable gases discharged from the mixing condenser to maintain a stable low-pressure state within the system. The parallel execution of the two processes reduces pressure fluctuations and supports efficient mass transfer of high-viscosity PGA melt.

[0064] The steam jet vacuum system uses multi-stage ejectors to progressively compress gas, achieving the separation and transport of volatiles. In the multi-stage ejector system, the outlet of the previous ejector is directly connected to the inlet of the next ejector. The gas is progressively compressed under the drive of steam, creating a high-vacuum environment. During operation, the volatiles are extracted from the polymerization reaction system and enter the mixing condenser through the material pipeline. The insulation medium is wrapped around the outer wall of the material pipeline, and the temperature of the flowing heat medium is higher than the freezing point of the volatiles, preventing condensation blockage. For example, in the production of medical-grade polyglycolic acid sutures, this design avoids pipeline fouling caused by low temperatures, ensuring the smooth transport of volatiles in gaseous form.

[0065] The inlet of the liquid ring pump is directly connected to the gas outlet of the mixing condenser, drawing in non-condensable gases to maintain vacuum balance. During operation, the non-condensable gases are continuously discharged, with the outlet connected to the atmosphere or a tail gas treatment system for environmental compatibility. An internal spray system within the mixing condenser disperses the condensing medium into droplets, accelerating the liquefaction of condensable components; the bottom drain port connects to a liquid component collection device to promote condensate recovery. In practical applications, such as the preparation of biodegradable packaging films, the pumping rate of the liquid ring pump is dynamically matched to the volatile load to prevent vacuum fluctuations from affecting the continuity of devolatilization.

[0066] The synergistic logic of the two processes is based on system integration design. The steam jet vacuum system establishes a high vacuum to promote volatile separation, while the liquid ring pump compensates for pressure changes through gas extraction. In the polyglycolic acid polymerization devolatilization system, the synchronization of volatile transport and vacuum maintenance optimizes energy utilization and reduces downtime risks. Operational details include regular monitoring of pipeline sealing and heat transfer medium circulation to adapt to long-cycle operation in large-scale production. This arrangement improves the thermal stability and mechanical properties of polyglycolic acid products, meeting the requirements of high-end biomedical materials.

[0067] The specific implementation of the polyglycolic acid (PGA) polymerization devolatilization system involves the coordinated operation of a steam jet vacuum system, a mixing condenser, a liquid ring pump, and a utility system. The gases generated during the PGA polymerization reaction include oligomers, methanol, nitrogen, and oxygen, which are introduced into the steam jet vacuum system. The steam jet vacuum system operates under the drive of MG steam provided by a power steam system, which has specific molecular weight, temperature, pressure, and density parameters. The steam jet vacuum system includes multi-stage ejectors that operate sequentially, progressively increasing the vacuum level by compressing the gas stage by stage, creating a lower intake pressure and a higher intake temperature environment within the system. Under this vacuum environment, volatiles in the gas are more easily separated from the polymerization system. The intake temperature of the steam jet vacuum system is set to a higher value, and the intake pressure is set to a lower value to meet the high vacuum requirements of PGA polymerization devolatilization. In the multi-stage ejectors, the outlet of the previous stage ejector is directly connected to the inlet of the next stage ejector. The gas is progressively compressed under the drive of power steam. This series structure disperses the load of single-stage equipment, avoids pressure fluctuations, and improves mass transfer efficiency. For example, in the production of medical-grade polyglycolic acid sutures, a high vacuum environment effectively removes easily condensable components from high-viscosity melts, preventing incomplete volatilization.

[0068] The gas discharged from the steam jet vacuum system enters the mixing condenser. The mixing condenser employs a spray condensation method, where the MG liquid provided by the spray condensation system comes into full contact with the gas in a spray form. The MG liquid has specific temperature, pressure, and density parameters. The mixing condenser is equipped with a spray device that uses an array of nozzles to uniformly disperse the condensing medium, increasing the gas-liquid contact area and promoting the condensation and liquefaction of condensable components such as oligomers and methanol. The spray condensation process is based on a forced convection heat transfer mechanism; after the droplets mix with the high-temperature gas, they rapidly absorb heat, lowering the gas temperature and causing the condensable components to transform into a liquid state. After condensation, the condensable components in the gas are separated, while the non-condensable gas forms the tail gas. The tail gas temperature is set to a moderate value, and the pressure is set to a relatively high value to reduce the load on the subsequent liquid ring pump. In the context of biodegradable packaging film preparation, the uniform distribution of the spray device avoids incomplete local condensation and improves devolatilization efficiency.

[0069] Exhaust gas exits from the mixing condenser and enters the liquid ring pump. The liquid ring pump draws in the exhaust gas, maintaining the vacuum level of the mixing condenser and the system. The inlet of the liquid ring pump is directly connected to the gas outlet of the mixing condenser using a short-distance pipe or flange interface to minimize airflow resistance and pressure loss. The outlet of the liquid ring pump is connected to the atmosphere or a subsequent exhaust gas treatment system, depending on the environmental compliance of the exhaust gas components. During operation, non-condensable gases are continuously drawn in, creating a pressure gradient that supports unidirectional gas flow from the mixing condenser to the liquid ring pump, preventing operational interruptions caused by backflow. The liquid ring pump works in conjunction with the vapor jet vacuum system to compensate for gas volume changes during the condensation process and maintain system vacuum balance. For example, in the production of medical-grade polyglycolic acid, the pumping rate of the liquid ring pump is dynamically matched to the volatile load to ensure continuous stability of the devolatilization process.

[0070] During the devolatilization process, the insulation system uses a vapor-phase heat transfer medium to maintain the temperature of the relevant equipment. This medium has specific temperature ranges and pressure parameters. The insulation system maintains a high temperature inside the equipment and keeps the outer cylinder temperature within a suitable range, minimizing heat loss. The insulation medium is wound or wrapped around the outer wall of the system piping, using spiral winding or multi-layer wrapping to ensure uniform distribution of the heat transfer medium along the material piping surface, forming a continuous insulation layer. The temperature of the heat transfer medium flowing within the insulation medium piping is higher than the freezing point of the condensable components in the volatiles, preventing condensation and blockage during material transport. Based on the principle of heat conduction, the insulation system uses temperature sensors for real-time monitoring and precise temperature control. In the production of biodegradable polyglycolic acid (PGA) materials, the insulation design avoids pipeline fouling caused by low temperatures, supporting long-term system operation. The utility system includes a power steam system, a spray condensation system, and an insulation system. Each component provides power, condensation, and insulation support. The power steam system drives multi-stage ejectors, the spray condensation system enhances heat exchange, and the insulation system optimizes energy utilization. The steps are logically coherent. The steam jet vacuum system establishes a high vacuum to promote the separation of volatiles, the mixing condenser realizes condensation and recovery, and the liquid ring pump maintains the vacuum closed loop. This solves the problems of low efficiency and easy clogging of existing devolatilization systems and improves the purity and thermal stability of polyglycolic acid products.

[0071] The polyglycolic acid (PGA) polymerization devolatilization system integrates a vapor jet vacuum system, a mixing condenser, a liquid ring pump, and utilities to create a highly efficient devolatilization process that directly addresses the technical pain points of low mass transfer efficiency and poor process control. The vapor jet vacuum system employs a multi-stage ejector series design, with the outlet of the previous ejector directly connected to the inlet of the next, achieving progressive gas compression and gradually establishing a high vacuum environment. This progressive compression mechanism distributes the load on individual equipment stages, avoids sudden pressure changes, and improves the mass transfer efficiency for separating unreacted monomers and low-molecular-weight byproducts from high-viscosity PGA melt. In medical-grade suture production scenarios, the multi-stage ejectors, through stable vacuum control, prevent residual monomer accumulation due to pressure fluctuations during devolatilization, thereby optimizing product purity.

[0072] The mixing condenser is equipped with a spray device that supplies condensing medium through a condensing medium pipeline. The condensing medium, in the form of atomized droplets, fully contacts the volatiles, accelerating the condensation and liquefaction of condensable components such as oligomers and methanol based on the principle of forced convection heat transfer. The spraying operation increases the gas-liquid contact area, ensuring efficient conversion of condensable components into a liquid state, which is then introduced into the recovery system through the bottom drain port, while non-condensable gases are discharged through the gas outlet. The liquid ring pump inlet is directly connected to the gas outlet of the mixing condenser, continuously extracting non-condensable gases to maintain system vacuum balance. This direct link minimizes airflow resistance, supports continuous devolatilization, and reduces the risk of process interruption. For example, in the preparation of biodegradable packaging films, the coordinated control of spray condensation and the liquid ring pump matches changes in volatile load, improving devolatilization stability.

[0073] The utility system supports the devolatilization process. Power steam pipelines deliver power steam to the multi-stage ejectors, driving the compression action. Condensate pipelines supply condensate to the spray unit, optimizing heat exchange efficiency. Insulation medium pipelines are wound around the outer wall of the material pipeline from the polyglycolic acid polymerization reaction system outlet to the mixing condenser inlet. The temperature of the flowing heat medium is higher than the freezing point of the volatiles, preventing condensation blockage during transport. The insulation design uses spiral winding or multi-layer wrapping to form a continuous insulation layer, avoiding low-temperature-induced pipeline fouling in medical material production and enhancing system reliability. All components are logically interconnected. The steam jet vacuum system establishes a high vacuum to promote separation, the mixing condenser achieves condensation recovery, and the liquid ring pump maintains a vacuum closed loop. Parameter co-optimization addresses the existing system's imprecise control and insufficient mass transfer issues, ultimately improving the biodegradability and mechanical properties of the polyglycolic acid product.

[0074] Embodiment 1 of the present invention: In the production process of medical-grade polyglycolic acid sutures, the polyglycolic acid polymerization reaction system generates volatiles including unreacted monomers, low-molecular-weight byproducts such as oligomers, and methanol. If these components are not effectively removed, it will lead to a decrease in the thermal stability of the suture and a broadening of its molecular weight distribution. In this embodiment of the invention, the inlet of the steam jet vacuum system is connected to the polymerization reaction system, employing a multi-stage ejector structure. The outlet of the previous stage ejector is directly connected to the inlet of the next stage ejector, forming a series configuration. The power steam pipeline branches from the utility system, providing MG steam to each stage ejector with parameters including a temperature of 118°C, a pressure of 35 kPa, and a density of 0.97 kg / m³. The driving gas is compressed stage by stage, bringing the inhalation pressure below 0.05 kPa(A) and maintaining the inhalation temperature at 90°C. This multi-stage design disperses the compression load, avoids pressure fluctuations, and improves mass transfer efficiency. After the volatiles are extracted, they are transported to the mixing condenser via material pipelines. Insulation medium is wound around the outer wall of the material pipelines using a spiral winding method. The circulating heat medium is a vapor-phase medium, with the temperature set between 120℃ and 130℃, higher than the freezing point of condensable components in the volatiles, such as methanol, to prevent condensation blockage. The mixing condenser is equipped with a spray device that sprays MG liquid into the chamber through an array of nozzles. The MG liquid parameters are: temperature 25℃, pressure greater than 100kPa, and density 1167kg / m³, promoting the liquefaction of condensable components. The exhaust gas exits from the gas outlet at a pressure of 9kPa(A) and a temperature of 45℃, with a positive pressure difference from the intake pressure to ensure unidirectional gas flow. The inlet of the liquid ring pump is directly connected to the gas outlet of the mixing condenser to extract non-condensable gases such as nitrogen and oxygen to maintain system vacuum. The outlet is connected to the exhaust gas treatment system for purification. The drain port at the bottom of the mixing condenser is connected to a liquid component collection device to recover the condensate for resource recovery. The process of delivering volatiles to the vapor jet vacuum system and maintaining vacuum through a liquid ring pump is synchronized, forming a continuous devolatilization process. In medical applications, high vacuum and thermal insulation design reduce residual monomers, improving the mechanical strength and controllable degradation cycle of sutures.

[0075] Embodiment 2 of the present invention: In the production of biodegradable packaging films, the polymerization process of polyglycolic acid requires handling high-viscosity melts, and existing devolatilization systems are prone to clogging and inefficiency. This embodiment addresses this scenario by employing a steam jet vacuum system with multi-stage ejectors. MG steam is evenly distributed to each stage of the ejector via a power steam pipeline, with the suction pressure controlled at 0.05 kPa(A) and the suction temperature at 90°C, ensuring efficient separation of volatiles from the polymerization system. The material pipeline extends from the reaction system outlet to the mixing condenser inlet. The insulation medium pipeline uses a multi-layered coating, maintaining the heat medium temperature above 120°C, higher than the freezing point of oligomers and other components, thus preventing phase change accumulation during transport. The mixing condenser disperses the condensing medium into micron-sized droplets through a spray device, increasing the gas-liquid contact area. The exhaust gas parameters are a pressure of 9 kPa(A) and a temperature of 45°C. A liquid ring pump is directly connected to extract the gas, maintaining system vacuum balance. The drain outlet-guided recovery system extracts unreacted monomers; the power steam and condensate pipelines of the utility system work together, and the insulation system maintains the inner cylinder temperature at 200℃ and the outer cylinder temperature at 350℃, reducing heat loss. Through parameter optimization and equipment integration, the risk of thermal degradation in the production of biodegradable films has been solved, and the mechanical properties and environmental consistency of the films have been improved.

Claims

1. A polyglycolic acid polymerization devolatilization system, characterized in that, include: The inlet of the steam jet vacuum system is used to connect to the polyglycolic acid polymerization reaction system, and the outlet of the steam jet vacuum system is connected to the inlet of the mixing condenser. The steam jet vacuum system separates volatiles, including unreacted monomers and low-molecular-weight byproducts, from the polyglycolic acid polymerization reaction system and delivers the volatiles to the mixing condenser. The gas outlet of the mixing condenser is connected to the inlet of the liquid ring pump. The mixing condenser receives and condenses the volatiles, converting the condensable components into a liquid state, and allowing the non-condensable gases to be discharged from the gas outlet. The liquid ring pump draws non-condensable gas from the mixing condenser to establish and maintain a vacuum in the mixing condenser and the steam jet vacuum system; The utility system includes a power steam pipeline, a condensing medium pipeline, and an insulation medium pipeline; the power steam pipeline is connected to the steam jet vacuum system to provide power steam for the steam jet vacuum system; the condensing medium pipeline is connected to the mixing condenser to provide condensing medium for the mixing condenser; and the insulation medium pipeline is laid on the outer wall of the system pipeline to insulate the system pipeline.

2. The polyglycolic acid polymerization devolatilization system according to claim 1, characterized in that, The steam jet vacuum system includes a multi-stage ejector, with the outlet of the previous stage ejector connected to the inlet of the next stage ejector, so that the gas is compressed and transported in stages.

3. The polyglycolic acid polymerization devolatilization system according to claim 2, characterized in that, The power steam line is connected to each stage of the multi-stage injector.

4. The polyglycolic acid polymerization devolatilization system according to claim 1, characterized in that, The mixing condenser is equipped with a spray device, and the condensing medium pipeline is connected to the spray device, which sprays the condensing medium into the mixing condenser.

5. The polyglycolic acid polymerization devolatilization system according to claim 4, characterized in that, The insulation medium is wound or wrapped around the outer wall of the material pipeline between the outlet of the polyglycolic acid polymerization reaction system and the inlet of the mixing condenser.

6. The polyglycolic acid polymerization devolatilization system according to claim 5, characterized in that, The temperature of the heat medium flowing in the insulation medium pipeline is higher than the freezing point of the condensable components in the volatiles flowing in the material pipeline.

7. The polyglycolic acid polymerization devolatilization system according to claim 1, characterized in that, The suction pressure of the steam jet vacuum system is less than 1 kPa; the difference between the exhaust gas pressure at the outlet of the mixing condenser and the suction pressure of the steam jet vacuum system is positive.

8. The polyglycolic acid polymerization devolatilization system according to claim 1, characterized in that, The inlet of the liquid ring pump is directly connected to the gas outlet of the mixing condenser, and the outlet of the liquid ring pump is connected to the atmosphere or a subsequent exhaust gas treatment system.

9. The polyglycolic acid polymerization devolatilization system according to any one of claims 1-8, characterized in that, The bottom of the mixing condenser is provided with a drain port, which is connected to a liquid component collection device or a recovery system.

10. The polyglycolic acid polymerization devolatilization system according to claim 9, characterized in that, The process of the polyglycolic acid polymerization reaction system delivering volatiles to the steam jet vacuum system occurs simultaneously with the process of the liquid ring pump maintaining the system vacuum.

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