A heat conducting oil recycling system

Abstract

The utility model belongs to the technical field of industrial heat conduction oil regeneration treatment, concretely relates to a heat conduction oil regeneration recycling system, and a heat conduction oil regeneration recycling system, including heating device, retort device, condensing device, first storage device, secondary storage device, vacuum device, heating device includes raw material heating furnace, and raw material heating furnace is connected with retort device through feed pipe line, still be provided with upper discharge gate, lower discharge gate on retort device, the import of condensing device is connected with upper discharge gate through gas phase pipe line, and the outlet of condensing device is connected with liquid phase pipe line, and first storage device is connected with liquid phase pipe line through first discharge pipeline, and secondary storage device is connected with liquid phase pipe line through secondary discharge pipeline, and vacuum device is connected with condensing device, and is provided with valve for controlling liquid phase pipe line and one of first discharge pipeline and secondary discharge pipeline intercommunication, the utility model has the advantages of simple structure, high separation efficiency, convenient operation.

Description

Technical Field

[0001] This utility model belongs to the field of industrial heat transfer oil regeneration and treatment technology, specifically relating to a heat transfer oil regeneration and recycling system. Background Technology

[0002] In high-temperature industries such as polyester, synthetic fiber, and petrochemicals, hydrogenated terphenyl is widely used as a high-temperature liquid heat transfer fluid due to its excellent thermal stability. However, during long-term high-temperature operation, the heat transfer oil undergoes thermal cracking and condensation reactions, producing low-boiling-point and high-boiling-point components. The formation of low-boiling-point components lowers the oil's flash point, increasing safety risks; while high-boiling-point components can cause equipment coking and reduced heat transfer efficiency.

[0003] Common methods for regenerating heat transfer oil include distillation and membrane separation. For example, prior art document CN222593532U discloses a batch distillation apparatus for recovering centrifugal mother liquor, which includes components such as a batch distillation reactor, a distillation column, a condenser, an intermediate tank, a heavy phase product tank, and a light phase product tank. This apparatus achieves precise separation through the distillation column, and while the separation effect is good, it suffers from problems such as complex equipment structure, high investment cost, large footprint, and difficult operation and maintenance. Especially for materials prone to coking, such as hydrogenated terphenyl, the inside of the distillation column is easily clogged, making cleaning difficult.

[0004] Therefore, there is an urgent need to develop a treatment system that is simple in structure, low in investment cost, easy to operate and maintain, and particularly suitable for the regeneration of hydrogenated terphenyl. Utility Model Content

[0005] To address the aforementioned problems, the purpose of this utility model is to provide a heat transfer oil regeneration and recycling system that is simple in structure, has high separation efficiency, and is easy to operate.

[0006] To achieve the above objectives, the technical solution of this utility model is as follows:

[0007] A heat transfer oil regeneration and recycling system includes a heating device, a distillation kettle, a condensation device, a primary storage device, a secondary storage device, and a vacuum device;

[0008] The heating device includes a raw material heating furnace, which is connected to the distillation vessel via a feed pipe;

[0009] The distillation vessel is also equipped with an upper discharge port and a lower discharge port;

[0010] The inlet of the condensing device is connected to the upper discharge port via a gas phase pipeline, and the outlet of the condensing device is connected to a liquid phase pipeline.

[0011] The primary storage device is connected to the liquid phase pipeline via a primary discharge pipe;

[0012] The secondary storage device is connected to the liquid phase pipeline via a secondary discharge pipeline;

[0013] The vacuum device is connected to the condensation device to establish and maintain a vacuum environment;

[0014] A valve is provided to control the connection between the liquid phase pipeline and one of the primary discharge pipeline and the secondary discharge pipeline.

[0015] As a further preferred embodiment of this invention, a recovery pipeline is provided between the raw material heating furnace and the distillation vessel, with the direction of the recovery pipeline being opposite to that of the feed pipeline.

[0016] As a further preferred embodiment of this utility model, the liquid phase pipeline is provided with a sight glass, or the primary discharge pipeline and the secondary discharge pipeline are respectively provided with sight glasses.

[0017] As a further preferred embodiment of the present invention, the vacuum device includes a three-stage condenser, a vacuum buffer tank, and a vacuum pump group connected in sequence; the inlet of the three-stage condenser is connected to the condensation device and the primary storage device respectively through a first pipe and a second pipe connected in parallel.

[0018] As a further preferred embodiment of this invention, the vacuum pump assembly includes a low-level vacuum pump and a high-level vacuum pump connected in parallel.

[0019] As a further preferred embodiment of this invention, the low-level vacuum pump is a rotary vane vacuum pump or a water ring vacuum pump; the high-level vacuum pump is a Roots vacuum pump.

[0020] As a further preferred embodiment of the present invention, the heating device further includes a heat transfer oil pump disposed on the feed pipeline.

[0021] As a further preferred embodiment of the present invention, the heating device further includes an expansion tank connected to the feed pipe.

[0022] As a further preferred embodiment of the present invention, the condensation device includes a primary condenser and a secondary condenser connected in sequence.

[0023] As a further preferred embodiment of this utility model, the lower discharge port is connected to the collection tank via a recombining branch pipeline.

[0024] The beneficial effects of this utility model are:

[0025] The system provided by this utility model has a simplified system structure, omitting complex equipment such as distillation columns, which greatly reduces equipment investment costs and floor space, and is particularly suitable for the regeneration production needs of hydrogenated terphenyl.

[0026] The system provided by this utility model omits complex equipment such as distillation columns through a simplified system structure, thus avoiding the risk of tower equipment blockage caused by the cracking and coking of hydrogenated terphenyl at high temperatures.

[0027] The system provided by this utility model has a simplified system structure, allowing operators to intuitively and accurately determine the timing of fraction switching through a sight glass. The process is simple and easy to master.

[0028] The system provided by this invention combines external circulation heating with vacuum distillation, achieving gentle and uniform heating, effectively inhibiting secondary cracking of oil, ensuring long-term stable operation of the system, and good repeatability between regeneration batches. Attached Figure Description

[0029] Appendix Figure 1 This is a schematic diagram of the structure of this utility model.

[0030] Figure description: Feed pipeline 10, recovery pipeline 11, gas phase pipeline 12, liquid phase pipeline 13, primary discharge pipeline 14, secondary discharge pipeline 15, first pipeline 16, second pipeline 17, recombining pipeline 18;

[0031] Raw material heating furnace 110, heat transfer oil pump 120, expansion tank 130;

[0032] Distillation apparatus 200;

[0033] Primary condenser 310, secondary condenser 320;

[0034] Primary storage device 400;

[0035] 500 secondary storage devices;

[0036] Three-stage condenser 610, vacuum buffer tank 620, vacuum pump set 630. Detailed Implementation

[0037] In the description of this utility model, it should be understood that the terms "upper", "lower", "inner", "outer", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship that the utility model product is usually placed in during use, or the orientation or positional relationship that is commonly understood by those skilled in the art. They are only used to facilitate the description of this utility model and to simplify the description, and are not intended to indicate or imply that the device or component 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 utility model.

[0038] Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0039] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, terms such as "set" and "connection" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0040] As attached Figure 1 As shown, this embodiment provides a heat transfer oil regeneration and recycling system, including a heating device, a distillation kettle device 200, a condensation device, a primary storage device 400, a secondary storage device 500, and a vacuum device.

[0041] The heating device includes a raw material heating furnace 110, which can be a diesel heating furnace 110. Its set working temperature is determined by experiment based on the brand and deterioration of the heat transfer oil, but must not exceed the maximum allowable operating temperature of the oil. The temperature range is usually 250~280℃.

[0042] The feed line 10 is made of stainless steel, and the raw material heating furnace 110 is connected to the lower middle part of the distillation vessel 200 through the feed line 10, forming the main heating circuit. This embodiment also includes a recovery line 11 with the same specifications and materials as the feed line 10. The recovery line 11 is located in the upper middle part of the distillation vessel 200, arranged parallel to the feed line 10 but with opposite flow directions, together forming a complete circulating heating system. The advantages of this design are: First, in this design, the raw material heating furnace acts as an independent and specialized heat source, and its power setting, heating curve, and combustion efficiency can be optimized to the best state without being disturbed by the complex vapor-liquid balance conditions inside the distillation vessel. Heat is efficiently generated outside the system and then stably transported to the process materials through the circulation pipeline, making the heating process more stable, more efficient, and easier to automatically control. Second, the parallel dual-pipeline design constitutes a reliable circulation channel. On the one hand, the huge circulation flow ensures that even if a small amount of low-boiling substances vaporize instantaneously, they will be quickly carried away from the heating surface, effectively suppressing the risk of "vapor resistance" or even violent boiling within the pipeline. On the other hand, when process adjustments or emergency shutdowns are required, the independent circulation loop can continue to operate, enabling controlled cooling of the system and avoiding the dangers caused by heat accumulation.

[0043] Furthermore, the heating device also includes a heat transfer oil pump 120 installed on the feed pipe 10, and an expansion tank 130 connected to the feed pipe 10. The heat transfer oil pump 120 can be an RY100-65-315 type hot oil pump; the expansion tank 130 is installed above the device 200 and is generally a pressure vessel, usually made of stainless steel. Its nominal solvent should be determined according to the total capacity of the heat transfer oil in the entire system and the expansion coefficient within the operating temperature range, usually 1.2 to 1.5 times the total system capacity. The top should also be equipped with conventional structures such as a nitrogen charging port, a breather valve, a pressure gauge, and an explosion-proof plate. The side is equipped with an inlet and outlet for high-temperature heat transfer oil. The outlet is connected to the feed pipe 10 through a balance pipe. Nitrogen gas can be charged into the container through the nitrogen charging port to maintain the pressure within a predetermined range, which is used to ensure the safe operation of the boiler heating device and to isolate air and prevent oxidation of the heat transfer oil.

[0044] The distillation vessel 200 can be designed as a vertical pressure vessel, and the material can be stainless steel. The distillation vessel 200 has an upper discharge port at the top, connected to the condenser via a gas phase pipeline 12; and a lower discharge port at the bottom, connected to the collection tank 210 via a heavy component pipeline 18. In this embodiment, with an external circulating heating device providing the heat source, the internal heating coil of the distillation vessel 200 does not need to be installed. This has the following advantages: First, the heating surface of the coil inside a traditional distillation vessel is the area with the highest temperature and the most severe coking. Coking on the coil surface significantly reduces heat transfer efficiency, leading to increased energy consumption, and is extremely difficult to clean, requiring shutdown for mechanical or chemical cleaning. This design completely eliminates this failure point, ensuring long-term stable operation of the equipment. Second, by circulating the heat transfer oil to be regenerated between the external heating furnace and the distillation vessel at a high flow rate, the temperature of the material inside the entire vessel is highly uniform, avoiding localized overheating. Localized overheating is the main cause of further cracking of the heat transfer oil, generating more heavy components and coking. This design maximizes the protection of the oil through gentle and uniform heating, improving regeneration yield and quality. Third, by removing the complex internal coils, the distillation vessel becomes a simple, empty container, significantly reducing manufacturing costs. Simultaneously, this eliminates the significant safety hazard of heating medium mixing with process materials due to coil leaks. In terms of maintenance, inspection and cleaning of the vessel become more direct and convenient, shortening maintenance cycles and reducing maintenance costs. Fourth, under vacuum conditions, the boiling point of the system decreases. This design utilizes external circulating heating to provide the necessary heat, promoting efficient evaporation of low-boiling-point substances. Furthermore, due to uniform heating, violent boiling within the vessel is avoided, ensuring a smooth distillation process and achieving clear fractionation.

[0045] It is worth noting that this system only includes the distillation kettle unit, excluding the rectification column unit. The purpose and advantages are as follows: First, the regeneration of hydrogenated terphenyl is not aimed at obtaining a high-purity single component; the core objective is to effectively separate the cracked components (light and heavy components) with significantly different boiling points from the intact bulk oil. Therefore, the precision fractionation provided by the rectification column is unnecessary. Conversely, the complex structure of the rectification column is easily clogged by high-boiling-point polymers and coking products generated from the cracking of hydrogenated terphenyl, making cleaning extremely difficult. Second, omitting the rectification column not only reduces initial equipment investment costs but also simplifies the piping layout and reduces the footprint. In terms of operation and maintenance, it avoids the complex operations of periodic cleaning, packing replacement, and fine adjustment of the reflux ratio of the rectification column, significantly reducing maintenance costs and workload. Third, operators do not need to focus on the complex vapor-liquid balance and temperature gradient within the rectification column; the entire regeneration process can be completed simply by controlling the heating temperature, system pressure, and observing the properties of the condensate (e.g., through a sight glass). This reduces the technical requirements for operators, increases process stability, and is suitable for intermittent, batch-based regeneration operations at the factory site.

[0046] The condensation unit comprises a primary condenser 310 and a secondary condenser 320 connected in sequence. The primary condenser 310 can be a fixed tube sheet heat exchanger, with circulating water as the cooling medium; the secondary condenser 320 can be a graphite condenser, with chilled water as the cooling medium. The two are connected by stainless steel piping. The purpose of this design is twofold: First, to distribute the condensation load to two independent units. The primary condenser serves as the main condensation unit, with a robust structure and high processing capacity, while the secondary condenser serves as the fine condensation unit. In particular, the selection of a graphite condenser with excellent corrosion resistance effectively handles acidic or corrosive components that may be present in low-boiling-point substances, ensuring the reliability and stability of the system during long-term operation. Second, after two stages of deep condensation, the gas entering the subsequent tertiary condenser and vacuum pump unit is relatively "dry" non-condensable gas, free of large amounts of condensable oil and gas. This significantly reduces the processing load on the vacuum system, prevents oil and gas from condensing, emulsifying, or coking within the vacuum pump, thereby protecting the expensive vacuum equipment and maintaining the long-term stability of the entire system's vacuum level—a crucial prerequisite for the smooth operation of the regeneration process. Third, by precisely controlling the temperature of the two-stage condenser, physical "fraction cutting" can be achieved. This clear physical separation allows operators to more clearly determine fraction switching points (such as switching from light components to the bulk) through sight glasses in subsequent pipelines, effectively reducing cross-contamination between different fractions. This ensures both the quality of recycled oil and the yield of high-value products.

[0047] The primary storage unit 400 can be a stainless steel tank, connected to the liquid phase pipeline 13 via the primary discharge pipe 14, primarily used to receive light component liquids. The secondary storage unit 500 can also be a stainless steel tank, connected to the liquid phase pipeline 13 via the secondary discharge pipe 15. There can be one or multiple tanks connected in parallel, used to collect the regenerated heat transfer oil product. The connection point between the liquid phase pipeline 13 and the primary discharge pipe 14 is also the connection point between the liquid phase pipeline 13 and the secondary discharge pipe 15; therefore, a valve (three-way valve) can be installed at this connection point. If the connection points are different, valves (such as pneumatic shut-off valves) can be installed on both the primary discharge pipe 14 and the secondary discharge pipe 15. Of course, the valves can be directly connected to a central control system (such as a DCS or PLC) to ultimately achieve automatic switching control of the distillate flow direction. A sight glass is installed on the liquid phase pipeline 13; this sight glass can be a pressure-resistant and high-temperature-resistant borosilicate glass observation window, providing operators with a direct observation channel for judging the distillate composition and the timing of switching. Of course, sight glasses can also be installed upstream of the primary discharge pipe 14 and the secondary discharge pipe 15, respectively. Furthermore, cameras can be installed at the sight glasses to utilize algorithms to identify changes in color and transparency, laying the foundation for unmanned operation. The purpose of this design is to construct a fraction management system integrating accurate judgment, reliable switching, and flexible collection: First, the sight glasses allow direct observation of the continuous changes in the condensate's color (from colorless to light yellow / amber), transparency (from clear to possibly turbid), and flowability (observing the liquid flow state), enabling the most direct determination of the fraction's essential composition. This physical property-based judgment method is more accurate and reliable than relying solely on indirect parameters such as temperature or time, especially when handling complex mixtures like hydrogenated terphenyl, effectively ensuring the high-purity separation of light components from qualified products. Second, the valve design ensures that only one flow path (leading to the primary or secondary storage tank) is unobstructed at any given time. This eliminates the possibility of cross-contamination between different fractions during the collection process, thus strictly ensuring the quality of the regenerated heat transfer oil product and making the collected light components purer, which is convenient for subsequent disposal or utilization.

[0048] The vacuum device includes a three-stage condenser 610, a vacuum buffer tank 620, and a vacuum pump unit 630 connected in sequence.

[0049] The tertiary condenser 610 can be a plate heat exchanger, and the cooling medium can be an aqueous ethylene glycol solution. The inlet of the tertiary condenser 610 is connected to the condensing unit and the primary storage unit 400 via a first pipe 16 and a second pipe 17 connected in parallel. The first pipe 16 is led out from the top of the liquid phase pipe 13 at the outlet of the secondary condenser 320 (or completely independently of the liquid phase pipe 13), and it is necessary to ensure that the exit point is higher than the liquid phase pipe 13 to ensure that the first pipe 16 only extracts the gas phase component. The second pipe 17 is led out from the top of the primary storage unit 400. Before the primary discharge pipe 14 is closed, the primary storage unit 400 is connected to the system pressure, and non-condensable gases will also accumulate at its top. Therefore, the parallel dual-pipe design ensures that the vacuum pump can effectively remove the non-condensable gases in that branch regardless of which storage tank the condensate flows to.

[0050] The 620 vacuum buffer tank can be made of stainless steel and can be equipped with a multi-stage baffle demister inside to capture entrained droplets. A drain port can be provided at the bottom of the tank to discharge droplets.

[0051] Vacuum pump unit 630 includes a low-stage vacuum pump and a high-stage vacuum pump connected in parallel. The low-stage vacuum pump can be a rotary vane vacuum pump (such as the 2X-70A type) or a water ring vacuum pump (such as the 2BE1-303 type); the high-stage vacuum pump can be a Roots vacuum pump (such as the ZJP-600 type). The vacuum system can be equipped with an automatic control program, which starts the low-stage vacuum pump first and automatically starts the high-stage vacuum pump when the system pressure drops to 8 kPa. A pressure interlock protection is set, which automatically alarms when the system pressure abnormally rises to 20 kPa and automatically shuts down when it rises to 30 kPa. In actual operation, this vacuum system can reduce the system pressure from atmospheric pressure to 1.5 kPa within 25 minutes and maintain a pressure fluctuation range of ±0.2 kPa throughout the distillation process.

[0052] The workflow of this recycling system is as follows:

[0053] 1. System Preparation and Feeding: a. Ensure all valves are in the correct open / closed position. b. Start the heat transfer oil pump 120 to pump the hydrogenated terphenyl heat transfer oil to be regenerated from the external storage tank into the distillation vessel 200 through the feed pipeline 10. Stop feeding when the liquid level in the vessel reaches 80% of the nominal volume.

[0054] 2. Start the circulating heating: a. Keep the heat transfer oil pump 120 running. At this time, it drives the heat transfer oil in the kettle to flow out from the recovery pipe 11 and enter the raw material heater 110. Start the raw material heater 110 and heat the circulating oil according to the preset temperature rise program. b. The heated high-temperature oil is transported back to the distillation kettle through the feed pipe 10. This circulation design, in conjunction with the natural convection of the hot fluid (heat rise and cool fall), achieves uniform and efficient heating of the materials in the kettle.

[0055] 3. Establish and stabilize the system vacuum: a. When the temperature of the distillation vessel rises to approximately 150°C, start the low-level vacuum pump to begin evacuating the system. b. Observe the system pressure. When the pressure drops to the allowable start-up pressure of the high-level vacuum pump, start the high-level vacuum pump. The two pumps work together to quickly and stabilize the system operating pressure within the target range.

[0056] 4. Reduced pressure distillation and precise fraction cutting:

[0057] a. Light Component (Low-Boiling Compounds) Extraction: Under set low pressure and high temperature, the low-boiling compounds in the heat transfer oil undergo vigorous vaporization. The vapor enters the primary condenser 310 and the secondary condenser 320 sequentially through the outlet on the distillation vessel and the vapor phase pipeline 12, where it is condensed into a liquid state. The operator closely observes this through the sight glass on the liquid phase pipeline 13. Initially, the condensate is typically colorless or pale yellow and clear. At this time, ensure that the control valve directs the condensate to the primary storage unit 400. Meanwhile, the vacuum system continuously extracts non-condensable gases through parallel pipelines to maintain stable system pressure.

[0058] b. As distillation proceeds, the content of low-boiling-point substances gradually decreases. When the color of the condensate steadily changes from light yellow to amber (the characteristic color of intact hydrogenated terphenyl) as observed through the sight glass, it is determined that the light components have been largely distilled off, and the main heat transfer oil begins to distill. Immediately switch the control valve to change the flow direction of the condensate from the primary storage unit 400 to the secondary storage unit 500, and begin collecting the regenerated heat transfer oil product.

[0059] c. Continuous monitoring; when the distillation rate decreases significantly or reaches the predetermined process requirements, the distillation process is considered complete.

[0060] 5. System Shutdown: Stop heating and maintain circulation and vacuum for cooling. Once the temperature drops below the safe operating temperature (80℃), slowly introduce nitrogen or dry compressed air into the system (or introduce nitrogen during the high-temperature stage and dry compressed air during the low-temperature stage) to break the vacuum and restore atmospheric pressure. Then open the valve on the heavy component pipeline 18 and discharge the remaining high-boiling-point heavy components (including some coking matter and solid impurities) into the collection tank 210 through the bottom outlet of the distillation vessel. Shut down circulation and enter standby mode.

[0061] The specific embodiments described herein are merely illustrative examples illustrating the spirit of this utility model. Those skilled in the art to which this utility model pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of this utility model or exceeding the scope defined by the appended claims.

Claims

1. A heat transfer oil regeneration and recycling system, characterized in that: It includes a heating device, a distillation kettle (200), a condensation device, a primary storage device (400), a secondary storage device (500), and a vacuum device; The heating device includes a raw material heating furnace (110), which is connected to the distillation vessel device (200) via a feed pipe (10); The distillation vessel (200) is also provided with an upper discharge port and a lower discharge port; The inlet of the condenser is connected to the upper outlet via a gas phase pipeline (12), and the outlet of the condenser is connected to a liquid phase pipeline (13). The primary storage device (400) is connected to the liquid phase pipeline (13) through the primary discharge pipeline (14); The secondary storage device (500) is connected to the liquid phase pipeline (13) through the secondary discharge pipeline (15); The vacuum device is connected to the condensation device to establish and maintain a vacuum environment; A valve is provided to control the connection between the liquid phase pipeline (13) and one of the primary discharge pipeline (14) and the secondary discharge pipeline (15).

2. The heat transfer oil regeneration and recycling system according to claim 1, characterized in that: A recovery pipeline (11) is also provided between the raw material heating furnace (110) and the distillation vessel (200), which is opposite to the conveying direction of the feed pipeline (10).

3. The heat transfer oil regeneration and recycling system according to claim 1, characterized in that: The liquid phase pipeline (13) is equipped with a sight glass, or the primary discharge pipeline (14) and the secondary discharge pipeline (15) are respectively equipped with sight glasses.

4. The heat transfer oil regeneration and recycling system according to claim 1, characterized in that: The vacuum device includes a three-stage condenser (610), a vacuum buffer tank (620), and a vacuum pump group (630) connected in sequence; the inlet of the three-stage condenser (610) is connected to the condensation device and the primary storage device (400) through a first pipe (16) and a second pipe (17) connected in parallel.

5. The heat transfer oil regeneration and recycling system according to claim 4, characterized in that: The vacuum pump assembly (630) includes a low-level vacuum pump and a high-level vacuum pump connected in parallel.

6. The heat transfer oil regeneration and recycling system according to claim 5, characterized in that: The low-level vacuum pump is a rotary vane vacuum pump or a water ring vacuum pump; the high-level vacuum pump is a Roots vacuum pump.

7. The heat transfer oil regeneration and recycling system according to claim 1, characterized in that: The heating device also includes a heat transfer oil pump (120) installed on the feed pipeline (10).

8. The heat transfer oil regeneration and recycling system according to claim 1, characterized in that: The heating device also includes an expansion tank (130) connected to the feed pipe (10).

9. The heat transfer oil regeneration and recycling system according to claim 1, characterized in that: The condensation device includes a primary condenser (310) and a secondary condenser (320) connected in sequence.

10. A heat transfer oil regeneration and recycling system according to claim 1, characterized in that: The lower discharge port is connected to the collection tank (210) via a recombining branch pipeline (18).

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