Closed self-circulating cooling device for cooling of vinyl chloride compressor oil
By adopting a closed self-circulating cooling device in the vinyl chloride production system, a self-circulating system is formed by using plate heat exchangers and oil coolers, and 7℃ demineralized water is used as the cooling medium. This solves the problems of high labor intensity in temperature control and leakage in oil cooling equipment, and achieves stable operation and extended service life of the equipment.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- 新疆圣雄氯碱有限公司
- Filing Date
- 2025-07-31
- Publication Date
- 2026-07-07
AI Technical Summary
The compressor oil cooling system in the vinyl chloride production system suffers from problems such as high labor intensity in temperature control operations and frequent leaks in the oil cooling equipment, which affect the normal operation of the production unit.
A closed-loop self-circulating cooling device is adopted, which uses a plate heat exchanger and an oil cooler to form a closed-loop self-circulating system. 7℃ demineralized water is used as the cooling medium to avoid corrosion of the oil cooler by 7℃ process water, thereby improving the service life and temperature control efficiency of the oil cooling equipment.
It reduces the labor intensity of temperature control, decreases the leakage frequency of oil cooling equipment, and improves the service life of equipment and the stability of compressor oil cooling.
Smart Images
Figure CN224470073U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of compressor oil cooling technology, and is a closed self-circulating cooling device for cooling vinyl chloride compressor oil. Background Technology
[0002] The main reactants and products of the vinyl chloride production unit in a chemical plant are gaseous media. The pipelines between various equipment are mainly equipped with screw compressors as power transmission equipment. Screw compressors are a type of gas compression equipment widely used in industrial fields.
[0003] Screw compressors, with their advantages of high efficiency, reliability, flexibility, and environmental friendliness, have become one of the mainstream models in the industrial compression field. Their disadvantage is their strict requirements for lubricating oil quality and operating oil temperature. Screw compressors require oil cooling equipment (shell-and-tube heat exchangers) to control the oil temperature. In the summer in Northwest China, a chemical plant uses 7°C water (process water discharged from other units at 7°C) to cool the compressor oil, and uses internal circulating water for cooling in winter, ultimately controlling the compressor oil temperature at 70°C. Due to changes in ambient temperature and compressor operating load, on-site personnel need to adjust the temperature frequently based on changes in compressor discharge temperature, averaging once per hour, resulting in high labor intensity for on-site operators.
[0004] The circulating water and the 7℃ water are of poor quality, containing a high amount of corrosive media. Prolonged use of the oil-cooled equipment can lead to corrosion and thinning of the tube walls, causing leaks. Leaking cooling water can also mix with the oil phase, triggering a compressor-induced equipment shutdown and threatening normal production. Currently, the oil-cooled equipment experiences two leaks per year. After shutdown and inspection, it was found that both leaks were caused by corrosion and thinning of the heat exchange tube walls. The maintenance costs for the heat exchange tubes in the oil-cooled equipment are also high.
[0005] In summary, the compressor oil cooling method in vinyl chloride production systems suffers from high labor intensity in temperature control operations and frequent oil cooling equipment leaks, which have become urgent technical challenges for enterprises to solve. Summary of the Invention
[0006] This invention provides a closed-loop self-circulating cooling device for cooling the oil of vinyl chloride compressors, which overcomes the shortcomings of the prior art and can effectively solve the problems of high labor intensity in temperature control and high leakage accident rate of oil cooling equipment in existing vinyl chloride production systems.
[0007] The technical solution of this utility model is achieved through the following measures: a closed-loop self-circulating cooling device for cooling vinyl chloride compressor oil, comprising a closed-loop circulating water tank, a plate heat exchanger, and an oil cooler. A demineralized water pipeline is fixedly connected to the first inlet at the top of the closed-loop circulating water tank. A first circulation pipeline is fixedly connected between the first outlet at the bottom of the closed-loop circulating water tank and the left inlet of the plate heat exchanger. A 7°C water supply pipeline is fixedly connected to the right inlet of the plate heat exchanger. A 7°C water return pipeline is fixedly connected to the left outlet of the plate heat exchanger. A second circulation pipeline is fixedly connected between the right outlet of the plate heat exchanger and the bottom inlet of the oil cooler. A compressor oil input pipeline is fixedly connected to the left inlet of the oil cooler. A third circulation pipeline is fixedly connected between the top outlet of the oil cooler and the second inlet at the top of the closed-loop circulating water tank. A compressor oil output pipeline is fixedly connected to the right outlet of the oil cooler.
[0008] The following are further optimizations and / or improvements to the above-mentioned utility model technical solution:
[0009] The second outlet at the bottom of the aforementioned closed circulating water tank is fixedly connected to a sampling pipeline.
[0010] The top outlet of the aforementioned closed circulating water tank is fixedly connected to an emptying pipeline.
[0011] The aforementioned closed circulating water tank is fixedly equipped with a level gauge and a first temperature gauge.
[0012] A second temperature gauge is fixedly installed on the aforementioned second circulation pipeline.
[0013] A circulating water transfer pump is fixedly installed on the aforementioned first circulation pipeline.
[0014] A filter is fixedly installed on the aforementioned 7℃ water supply pipeline.
[0015] A first control valve is fixedly installed on the aforementioned demineralized water pipeline.
[0016] A second control valve is fixedly installed on the 7℃ water supply pipeline between the inlet of the aforementioned 7℃ water supply pipeline and the inlet of the filter.
[0017] The aforementioned device also includes a controller, a circulating water transfer pump, a first control valve, a level gauge, a first thermometer, a second thermometer, and a second control valve, all of which are electrically connected to the controller.
[0018] This utility model has a reasonable and compact structure and is easy to use. It first uses 7°C process water to cool the demineralized water in a plate heat exchanger, and then uses low-temperature demineralized water as the cooling medium for the oil cooler. Finally, the demineralized water is returned to the closed circulating water tank, forming a closed self-circulating system for cooling the compressor oil in the vinyl chloride production system. This avoids corrosion of the oil cooler by the 7°C process water, improves the service life of the oil cooler, and also improves the temperature control efficiency for cooling the compressor oil. Attached Figure Description
[0019] Appendix Figure 1 This is a schematic diagram of the process flow of this utility model.
[0020] Appendix Figure 1 The codes in the diagram are as follows: 1 is a closed circulating water tank, 2 is a plate heat exchanger, 3 is an oil cooler, 4 is a demineralized water pipeline, 5 is the first circulation pipeline, 6 is a 7℃ water supply pipeline, 7 is a 7℃ water return pipeline, 8 is the second circulation pipeline, 9 is the compressor oil input pipeline, 10 is the third circulation pipeline, 11 is the compressor oil output pipeline, 12 is the sampling pipeline, 13 is the venting pipeline, 14 is the level gauge, 15 is the first thermometer, 16 is the second thermometer, 17 is the circulating water transfer pump, 18 is the filter, 19 is the first control valve, and 20 is the second control valve. Detailed Implementation
[0021] This utility model is not limited to the following embodiments, and the specific implementation method can be determined according to the technical solution of this utility model and the actual situation.
[0022] Unless otherwise specified, all equipment and devices used in this invention are existing, publicly known, and commonly used equipment and devices in the field.
[0023] In this utility model, for ease of description, the description of the relative positions of the components is based on the appendix to the specification. Figure 1 The layout is described using a diagrammatic method, such as the positional relationships of front, back, top, bottom, left, and right, which are based on the instructions attached. Figure 1 The orientation of the layout is determined by the direction of the map.
[0024] The present invention will be further described below with reference to the embodiments and accompanying drawings:
[0025] Example 1: As shown in the attached document Figure 1 As shown, the closed-loop self-circulating cooling device for cooling vinyl chloride compressor oil includes a closed-loop circulating water tank 1, a plate heat exchanger 2, and an oil cooler 3. A demineralized water pipeline 4 is fixedly connected to the first inlet at the top of the closed-loop circulating water tank 1. A first circulation pipeline 5 is fixedly connected between the first outlet at the bottom of the closed-loop circulating water tank 1 and the left inlet of the plate heat exchanger 2. A 7°C water supply pipeline 6 is fixedly connected to the right inlet of the plate heat exchanger 2. A 7°C water return pipeline 7 is fixedly connected to the left outlet of the plate heat exchanger 2. A second circulation pipeline 8 is fixedly connected between the right outlet of the plate heat exchanger 2 and the bottom inlet of the oil cooler 3. A compressor oil input pipeline 9 is fixedly connected to the left inlet of the oil cooler 3. A third circulation pipeline 10 is fixedly connected between the top outlet of the oil cooler 3 and the second inlet at the top of the closed-loop circulating water tank 1. A compressor oil output pipeline 11 is fixedly connected to the right outlet of the oil cooler 3.
[0026] As needed, the medium stored in the closed circulating water tank 1 is demineralized water. It first enters the plate heat exchanger 2 for cooling, and then enters the oil cooler 3 to cool the compressor oil in the vinyl chloride production system. The demineralized water discharged from the oil cooler 3 returns to the closed circulating water tank 1, forming a closed self-circulating demineralized water oil cooling system, which improves the service life of the oil cooler 3.
[0027] Inside the plate heat exchanger 2, process water at 7°C cools the demineralized water. The cooled demineralized water then enters the oil cooler 3, while the 7°C process water discharged from the plate heat exchanger 2 enters the downstream process system.
[0028] Oil cooler 3 is a shell-and-tube type oil-cooled heat exchanger used to cool the compressor oil in the vinyl chloride production system. Oil cooler 3 includes a tube side and a shell side. Low-temperature demineralized water enters the shell side, and vinyl chloride compressor oil enters the tube side. Low-temperature demineralized water in the shell side cools the vinyl chloride compressor oil in the tube side. The cooled vinyl chloride compressor oil enters the vinyl chloride compressor oil system. The demineralized water discharged from oil cooler 3 is returned to the closed circulating water tank 1.
[0029] This utility model may include one or more oil coolers 3. The low-temperature demineralized water output from the second circulation pipeline 8 can provide a cooling medium for each oil cooler 3. Each oil cooler 3 is connected in parallel. The left end inlet of each oil cooler 3 is fixedly connected to a compressor oil input pipeline 9, and the right end outlet of each oil cooler 3 is fixedly connected to a compressor oil output pipeline 11. Each compressor oil output pipeline 11 enters a different compressor oil system.
[0030] The aforementioned closed-loop self-circulating cooling device for cooling vinyl chloride compressor oil can be further optimized and / or improved according to actual needs:
[0031] Example 2: Its difference from Example 1 is as follows: (See attached) Figure 1 As shown, a sampling pipeline 12 is fixedly connected to the second outlet at the bottom of the closed circulating water tank 1.
[0032] As needed, the circulating medium in the closed circulating water tank 1 can be sampled and analyzed periodically through sampling pipeline 12. When the calcium and magnesium ions are greater than 100 mg / L, the turbidity is greater than 20 mg / L, the pH is less than 7, and the chloride ion is greater than 100 mg / L, the stored medium in the closed circulating water tank 1 needs to be replaced until the sampling and analysis indicators of the medium in the closed circulating water tank 1 are qualified.
[0033] Example 3: Its difference from Examples 1 to 2 is as follows: (See attached) Figure 1 As shown, the top outlet of the closed circulating water tank 1 is fixedly connected to an emptying pipeline 13.
[0034] As needed, the drain line 13 can ensure that the liquid circulation pressure in the closed circulating water tank 1 is normal and avoid negative pressure environment in the closed circulating water tank 1.
[0035] Example 4: Its difference from Examples 1 to 3 is as follows: (See attached) Figure 1 As shown, a level gauge 14 and a first temperature gauge 15 are fixedly installed on the closed circulating water tank 1.
[0036] As required, based on the compressor oil cooling requirements of the vinyl chloride production system, the temperature of the demineralized water in the closed circulating water tank 1 is controlled between 30°C and 40°C.
[0037] Example 5: It differs from Examples 1 to 4 in that: as shown in the appendix Figure 1 As shown, a second temperature gauge 16 is fixedly installed on the second circulation pipeline 8.
[0038] Example 6: Its difference from Examples 1 to 5 is as follows: (See attached) Figure 1 As shown, a circulating water transfer pump 17 is fixedly installed on the first circulation pipeline 5.
[0039] Example 7: Its difference from Examples 1 to 6 is as follows: (See attached) Figure 1 As shown, a filter 18 is fixedly installed on the 7℃ water supply pipeline 6.
[0040] As needed, the 7℃ water supply pipeline 6 transports 7℃ process water discharged from the upstream process system. This 7℃ process water contains corrosive impurities. Before entering the plate heat exchanger 2, the impurities are filtered by the filter 18 to reduce the corrosive damage of the 7℃ process water to the plate heat exchanger 2.
[0041] Example 8: It differs from Examples 1 to 7 in that, as shown in the appendix... Figure 1 As shown, a first control valve 19 is fixedly installed on the demineralized water pipeline 4.
[0042] Example 9: It differs from Examples 1 to 8 in that: as shown in the appendix Figure 1 As shown, a second control valve 20 is fixedly installed on the 7℃ water supply pipeline 6 between the inlet of the 7℃ water supply pipeline 6 and the inlet of the filter 18.
[0043] Example 10: It differs from Examples 1 to 9 in that, as shown in the appendix... Figure 1 As shown, the device also includes a controller, and the circulating water pump 17, the first control valve 19, the level gauge 14, the first thermometer 15, the second thermometer 16, and the second control valve 20 are all electrically connected to the controller.
[0044] As required, the level gauge 14, the first control valve 19 and the controller are interlocked. When the level gauge 14 displays a level value that is too high or too low in real time, the controller controls the opening of the first control valve 19 to maintain the liquid level of the medium in the closed circulating water tank 1 at the liquid level required by the process.
[0045] The first thermometer 15, the second thermometer 16, the second control valve 20, and the controller are interlocked. When the first thermometer 15 and the second thermometer 16 display a low temperature value in real time, the controller controls the valve opening of the second control valve 20 to adjust the input of 7℃ circulating process water and maintain the circulating demineralized water at the required temperature value.
[0046] The circulating water transfer pump 17 and the controller are interlocked. When one or more oil coolers 3 are running, the controller controls the circulating water transfer pump 17 to increase its operating power and increase the demineralized water circulation flow rate to ensure the required cooling medium for each oil cooler 3.
[0047] Depending on the needs, the pipelines and equipment of the closed-loop self-circulating cooling device for the vinyl chloride compressor oil cooling can also be equipped with conventional valves, thermometers, and pressure gauges known in the art, according to production requirements. The controller is a PLC controller, which is equipped with a Yokogawa CS3000DCS control system.
[0048] The above technical features constitute various embodiments of the utility model, which have strong adaptability and implementation effect. Unnecessary technical features can be added or removed according to actual needs to meet the needs of different situations.
[0049] The usage process of this utility model is as follows: First, the demineralized water enters the closed circulating water tank 1 through the demineralized water pipeline 4, and then enters the plate heat exchanger 2 through the first circulating pipeline 5. The 7°C process water discharged from the upstream process system enters the plate heat exchanger 2 through the 7°C water supply pipeline 6, cooling the demineralized water entering the plate heat exchanger 2 to obtain low-temperature demineralized water. The 7°C process water discharged from the plate heat exchanger 2 enters the downstream process system through the 7°C water return pipeline 7. Then, the low-temperature demineralized water enters the oil cooler 3 through the second circulating pipeline 8, and the compressor oil enters the oil cooler 3 through the compressor oil input pipeline 9. The low-temperature demineralized water in the oil cooler 3 cools the compressor oil, and the cooled compressor oil enters the compressor oil system through the compressor oil output pipeline 11. Finally, the low-temperature demineralized water discharged from the oil cooler 3 returns to the closed circulating water tank 1 through the third circulating pipeline 10.
Claims
1. A closed-loop self-circulating cooling device for cooling vinyl chloride compressor oil, characterized in that... The system includes a closed-loop circulating water tank, a plate heat exchanger, and an oil cooler. The first inlet at the top of the closed-loop circulating water tank is fixedly connected to a demineralized water pipeline. The first outlet at the bottom of the closed-loop circulating water tank is fixedly connected to a first circulation pipeline between it and the left inlet of the plate heat exchanger. The right inlet of the plate heat exchanger is fixedly connected to a 7°C water supply pipeline. The left outlet of the plate heat exchanger is fixedly connected to a 7°C water return pipeline. The right outlet of the plate heat exchanger is fixedly connected to a second circulation pipeline between it and the bottom inlet of the oil cooler. The left inlet of the oil cooler is fixedly connected to a compressor oil input pipeline. The top outlet of the oil cooler is fixedly connected to a third circulation pipeline between it and the second inlet at the top of the closed-loop circulating water tank. The right outlet of the oil cooler is fixedly connected to a compressor oil output pipeline.
2. The closed-loop self-circulating cooling device for cooling vinyl chloride compressor oil according to claim 1, characterized in that... A sampling pipeline is fixedly connected to the second outlet at the bottom of the closed circulating water tank.
3. The closed-loop self-circulating cooling device for cooling vinyl chloride compressor oil according to claim 1 or 2, characterized in that... The top outlet of the sealed circulating water tank is fixedly connected to an emptying pipeline.
4. The closed-loop self-circulating cooling device for cooling vinyl chloride compressor oil according to claim 3, characterized in that... A level gauge and a first temperature gauge are fixedly installed on the closed circulating water tank.
5. The closed-loop self-circulating cooling device for cooling vinyl chloride compressor oil according to claim 1, 2, or 4, characterized in that... A second temperature gauge is fixedly installed on the second circulation pipeline.
6. The closed-loop self-circulating cooling device for cooling vinyl chloride compressor oil according to claim 5, characterized in that... A circulating water pump is fixedly installed on the first circulation pipeline.
7. The closed-loop self-circulating cooling device for cooling vinyl chloride compressor oil according to claim 1, 2, 4, or 6, characterized in that... A filter is fixedly installed on the 7℃ water supply line.
8. The closed-loop self-circulating cooling device for cooling vinyl chloride compressor oil according to claim 7 or the present invention, characterized in that... A first control valve is fixedly installed on the demineralized water pipeline.
9. The closed-loop self-circulating cooling device for cooling vinyl chloride compressor oil according to claim 8, characterized in that... A second control valve is fixedly installed on the 7℃ water supply pipeline between the 7℃ water supply pipeline inlet and the filter inlet.
10. The closed-loop self-circulating cooling device for cooling vinyl chloride compressor oil according to claim 9, characterized in that... It also includes a controller, a circulating water transfer pump, a first control valve, a level gauge, a first thermometer, a second thermometer, and a second control valve, all of which are electrically connected to the controller.