Liquid drainage system of PTMEG device

Abstract

The utility model discloses a liquid drainage system of a PTMEG device, which relates to the technical field of treatment and comprises a primary cooler, a secondary cooler and a gas-liquid separation tank, the bottom of the gas-liquid separation tank is connected with the input end of a gathering pipe through a liquid drainage pipeline, the bottom of the primary cooler is connected with the input end of the gathering pipe through a liquid drainage pipeline, and the secondary cooler is connected with the input end of the gathering pipe through a liquid drainage pipeline. The output end of the gathering pipe is inserted below the bottom liquid level of the collecting tank, the gathering pipe is provided with a check valve above the collecting tank, the gathering pipe is sequentially provided with an upper water immersion sensor and a lower water immersion sensor from top to bottom in the collecting tank, and the upper water immersion sensor and the lower water immersion sensor are electrically connected with the controller. The controller is electrically connected with an electromagnetic valve on the liquid discharge pipe; the vacuum pump has the advantages that the liquid level in the collecting tank is always higher than the liquid outlet of the gathering pipe and forms water seal, so that gas is prevented from flowing back into the vacuum pump through the gathering pipe; and after the liquid in the collecting tank is collected, the liquid can be automatically discharged at regular intervals, so that the labor cost is reduced, and the normal production of the product quality is ensured.

Description

Technical Field:

[0001] The utility model relates to the technical field of treatment, in particular to a liquid discharging system of a PTMEG device. Background Art:

[0002] PTMEG (polytetrahydrofuran) is an important synthetic fiber raw material, which is widely used in the fields of textile, medical treatment, construction, etc. During the production of PTMEG in a PTMEG device, the produced PTMEG product is doped with part of methanol, and the methanol needs to be removed. After flash evaporation, the methanol is separated in a gaseous form and forms a gas-liquid mixture containing a small amount of PTMEG. The gas-liquid mixture will be introduced into a primary cooler for primary cooling, and the cooled liquid is discharged from the bottom of the primary cooler through a liquid discharging pipeline; the uncooled gas-liquid mixture is continuously introduced into a secondary cooler for secondary cooling through a primary vacuum pump, and the cooled liquid is discharged into a gas-liquid separation tank from the bottom through a pipeline for separation treatment, and the uncooled gas is transported to a subsequent condenser through a secondary vacuum pump for continuous cooling.

[0003] The existing problem is that: as the cooled liquid entering the gas-liquid separation tank gradually accumulates, it is usually necessary to manually open the liquid discharging valve at the bottom of the gas-liquid separation tank to discharge the liquid regularly, and it is necessary to observe at all times. The unseparated liquid is partially discharged into the incinerator as fuel for recycling, so as to avoid the accumulation of liquid in the gas-liquid separation tank. The purpose of partial discharge is to avoid the backflow of air through the gas-liquid separation tank, which affects the normal operation of the vacuum system. If it is completely discharged, the gas will enter the vacuum pump along the liquid discharging port, affecting the quality of the product. However, there may be negligence and misoperation of the staff, resulting in the backflow of air that cannot be supervised and detected, ultimately affecting the quality of the produced product, and at the same time increasing the labor cost. Content of the Utility Model:

[0004] The purpose of the utility model is to provide a liquid discharging system of a PTMEG device to solve the problems put forward in the above background art.

[0005] The utility model is implemented by the following technical solutions:

[0006] A PTMEG device drainage system includes a primary cooler, a secondary cooler and a gas-liquid separation tank. The gas outlet end of the primary cooler is transported to the input end of the secondary cooler through a primary vacuum pump. The liquid outlet end at the bottom of the secondary cooler is connected to the input end of the gas-liquid separation tank through a pipeline. The bottom of the gas-liquid separation tank is connected to the input end of a collecting pipe through a drainage pipeline. The bottom of the primary cooler is connected to the input end of the collecting pipe through a drainage pipeline. The output end of the collecting pipe is inserted below the liquid level at the bottom of the collecting tank. A check valve is installed above the collecting tank on the collecting pipe. An upper water immersion sensor and a lower water immersion sensor are installed on the collecting pipe in the collecting tank from top to bottom in sequence. The upper water immersion sensor and the lower water immersion sensor are electrically connected to a controller respectively. The controller is installed on the outer wall surface of the collecting tank. A drainage pipe is fixed at the bottom of the collecting tank. An electromagnetic valve is installed on the drainage pipe. The electromagnetic valve is electrically connected to the controller. An air inlet pipe is fixed on one side at the top of the collecting tank. A nitrogen supply valve is installed on the air inlet pipe.

[0007] Preferably, manual valves are installed at both ends of the drainage pipeline.

[0008] Preferably, a manual valve is also installed above the check valve on the collecting pipe.

[0009] Preferably, a breather valve and a safety valve are installed on the collecting tank.

[0010] Preferably, pressure gauges are installed on both sides of the nitrogen supply valve on the air inlet pipe.

[0011] Advantages of the present utility model: By inserting the liquid outlet of the collecting pipe below the liquid level in the collecting tank, the liquid in the collecting tank forms a water seal on the liquid outlet of the collecting pipe, thus avoiding the influence of gas backflow through the collecting pipe into the vacuum pump on the product. At the same time, by using two water immersion sensors to detect the liquid level in the collecting tank and the controller to control the electromagnetic valve, it can avoid the problem that the liquid level in the collecting tank is lower than the liquid outlet of the collecting pipe and the liquid in the collecting tank cannot be discharged normally after collection. Thus, it is no longer necessary for personnel to observe for drainage, reducing labor costs and ensuring the normal production of product quality. Description of the drawings:

[0012] Figure 1 It is a schematic structural diagram of the prior art;

[0013] Figure 2 It is a schematic structural diagram of the present utility model.

[0014] In the figure: 1. Primary cooler; 2. Secondary cooler; 3. Gas-liquid separation tank; 4. Primary vacuum pump; 5. Drainage pipeline; 6. Manifold; 7. Collection tank; 8. Check valve; 9. Upper water immersion sensor; 10. Lower water immersion sensor; 11. Controller; 12. Drain pipe; 13. Solenoid valve; 14. Inlet pipe; 15. Nitrogen supply valve; 16. Manual valve; 17. Breather valve; 18. Safety valve; 19. Pressure gauge. Detailed implementation manners:

[0015] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0016] Please refer to Figure 1-2 , the present invention provides a technical solution for a drainage system of a PTMEG device:

[0017] A drainage system of a PTMEG device includes a primary cooler 1, a secondary cooler 2 and a gas-liquid separation tank 3. The outlet end of the primary cooler 1 is transported to the input end of the secondary cooler 2 through a primary vacuum pump 4, and the liquid outlet end at the bottom of the secondary cooler 2 is connected to the input end of the gas-liquid separation tank 3 through a pipeline; the bottom of the gas-liquid separation tank 3 is connected to the input end of the manifold 6 through a drainage pipeline 5, and the bottom of the primary cooler 1 is connected to the input end of the manifold 6 through a drainage pipeline 5. Manual valves 16 are installed at both ends of the drainage pipeline 5. The output end of the manifold 6 is inserted below the liquid level at the bottom of the collection tank 7 to form a liquid seal to prevent air from entering and backflowing into the manifold 6. A check valve 8 is installed above the collection tank 7 on the manifold 6. The check valve 8 is specifically an ultra-low differential pressure check valve, which is of the wafer type, has good sealing performance and reliable operation, and can prevent the liquid in the collection tank 7 from flowing back. A manual valve 16 is also installed above the check valve 8 on the manifold 6. An upper water immersion sensor 9 and a lower water immersion sensor 10 are installed on the manifold 6 in the collection tank 7 from top to bottom in sequence. The upper water immersion sensor 9 and the lower water immersion sensor 10 are electrically connected to the controller 11 respectively. The controller 11 is installed on the outer wall surface of the collection tank 7. A breather valve 17 and a safety valve 18 are installed on the collection tank 7. A drain pipe 12 is fixed at the bottom of the collection tank 7. A solenoid valve 13 is installed on the drain pipe 12. The solenoid valve 13 is electrically connected to the controller 11. An inlet pipe 14 is fixed on one side of the top of the collection tank 7. A nitrogen supply valve 15 is installed on the inlet pipe 14. Pressure gauges 19 are installed on both sides of the nitrogen supply valve 15 on the inlet pipe 14.

[0018] The working principle is as follows: Since the output end of the collecting pipe 6 is inserted below the bottom liquid level of the collecting tank 7 to form a liquid seal, when the manual valve 16 is opened, the discharged liquid directly pours into the bottom of the collecting tank 7 and will not come into contact with air, thus avoiding air backflow. At the same time, as the liquid level in the collecting tank 7 continuously rises, the nitrogen pressure at the top of the collecting tank 7 increases. When the nitrogen pressure exceeds the set value of the nitrogen supply valve 15, the nitrogen supply valve 15 closes. When the pressure reaches the set pressure of the safety valve 18, the safety valve 18 opens to quickly release the excess nitrogen pressure in the tank and ensure that the pressure in the tank is always in a slightly positive pressure state.

[0019] When the liquid level in the tank reaches the upper water immersion sensor 9, the upper water immersion sensor 9 will transmit the detected signal to the controller 11, and the controller 11 controls the solenoid valve 13 to open to discharge the liquid (mainly composed of methanol and a small amount of PTMEG) in the collecting tank 7 into the combustion furnace for fuel recovery and utilization.

[0020] As the liquid level in the collecting tank 7 continuously decreases, the nitrogen pressure at the top of the collecting tank 7 decreases. The safety valve 18 is in the closed state, and the nitrogen supply valve 15 opens to inject nitrogen into the tank and ensure that the collecting tank 7 is in a slightly positive pressure state.

[0021] When the liquid level in the tank drops to the lower water immersion sensor 10, the lower water immersion sensor 10 will transmit the detected signal to the controller 11, and the controller 11 controls the solenoid valve 13 to close.

[0022] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A drainage system for a PTMEG device, comprising a primary cooler (1), a secondary cooler (2) and a gas-liquid separation tank (3). The gas outlet end of the primary cooler (1) is conveyed to the input end of the secondary cooler (2) through a primary vacuum pump (4), and the liquid outlet end at the bottom of the secondary cooler (2) is connected to the input end of the gas-liquid separation tank (3) through a pipeline; characterized in that: The bottom of the gas-liquid separation tank (3) is connected to the input end of the collecting pipe (6) through a liquid discharge pipeline (5). The bottom of the primary cooler (1) is connected to the input end of the collecting pipe (6) through a liquid discharge pipeline (5). The output end of the collecting pipe (6) is inserted below the bottom liquid level of the collecting tank (7). A check valve (8) is installed above the collecting tank (7) on the collecting pipe (6). An upper water immersion sensor (9) and a lower water immersion sensor (10) are sequentially installed from top to bottom in the collecting tank (7) on the collecting pipe (6). The upper water immersion sensor (9) and the lower water immersion sensor (10) are electrically connected to a controller (11) respectively. The controller (11) is installed on the outer wall surface of the collecting tank (7). A drain pipe (12) is fixed at the bottom of the collecting tank (7). A solenoid valve (13) is installed on the drain pipe (12). The solenoid valve (13) is electrically connected to the controller (11). An intake pipe (14) is fixed on one side of the top of the collecting tank (7). A nitrogen supply valve (15) is installed on the intake pipe (14).

2. The drain system of a PTMEG device according to claim 1, characterized in that: Manual valves (16) are installed at both ends of the liquid discharge pipeline (5).

3. The drain system of a PTMEG device according to claim 1, characterized in that: A manual valve (16) is also installed above the check valve (8) on the collecting pipe (6).

4. A draining system of a PTMEG device according to claim 1, characterized in that: A breather valve (17) and a safety valve (18) are installed on the collecting tank (7).

5. The drain system of a PTMEG device according to claim 1, characterized in that: Pressure gauges (19) are installed on both sides of the nitrogen supply valve (15) on the intake pipe (14).

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