Nitrogen sealing device

Abstract

The utility model relates to the technical field of storage tank sealing, in particular to a nitrogen sealing device which comprises a plurality of storage tanks, the top of each storage tank is connected with a gas-phase branch pipeline, the gas-phase branch pipelines are gathered and connected to a gas-phase main pipeline, the gas-phase main pipeline is connected to a condenser after passing through a breather valve and a flame arrester, the condenser is connected with an exhaust pipe and a condensate recovery pipe, and the condensate recovery pipe is connected with a liquid outlet pipe. The condensate recovery pipe is connected to a condensate storage tank; the gas-phase main pipeline is further connected with a nitrogen main pipe, and a coarse adjusting system and a fine adjusting system are arranged between the nitrogen main pipe and the gas-phase main pipeline in parallel through nitrogen pipes. According to the utility model, a plurality of storage tanks are integrated into one nitrogen sealing device, so that the equipment investment is reduced. In addition, a coarse adjusting system and a fine adjusting system are arranged on the adjusting system part of the nitrogen sealing device, one is used for the nitrogen sealing process of large nitrogen amount, the other is used for the process of fine adjusting system pressure, and the stability of the device is higher.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of storage tank sealing, and relates to a nitrogen sealing device. BACKGROUND

[0002] The nitrogen sealing device is a device for maintaining the pressure stability of the gas phase space in the storage tank, mainly by injecting nitrogen into the storage tank to displace the air in the tank, thereby preventing the contact of the material with oxygen and reducing the risk of oxidation of the material, while maintaining the pressure balance in the storage tank.

[0003] CN 208647686 U discloses a kind of storage tank nitrogen sealing device, it includes nitrogen inlet, nitrogen outlet, pressure sensor, breather valve and safety valve being arranged at the top of tank body, nitrogen inlet is communicated with nitrogen inlet pipeline, and first flow regulating valve and inlet control valve are arranged on nitrogen inlet pipeline;Nitrogen outlet is communicated with nitrogen outlet pipeline, and exhaust control valve and second flow regulating valve are arranged on nitrogen outlet pipeline;Breather valve is provided with gland, negative pressure valve disc, fire damper, rain cap and positive pressure valve disc;Pressure sensor, inlet control valve and exhaust control valve are all connected to automatic control system by transmission line.It is high in degree of automation, nitrogen loss is less, and safety is high.But since there are more flammable and explosive storage tanks in chemical production line, it is costly to install corresponding device and safety auxiliary facilities on each storage tank.In addition, nitrogen pipeline and regulating valve are designed to meet the maximum nitrogen flow, which can easily lead to poor sensitivity of regulating valve, and can easily cause inflexible adjustment and unstable pressure control. SUMMARY

[0004] The utility model provides a kind of nitrogen sealing device, it is the nitrogen sealing device that storage tank is uniformly arranged, avoid each storage tank according to nitrogen sealing device, greatly save equipment investment, and the stability of the nitrogen sealing device is strong.

[0005] The technical scheme of the utility model is to provide a kind of nitrogen sealing device, including multiple storage tanks, the top of each storage tank is connected with gas phase branch pipeline, each gas phase branch pipeline is again gathered and connected to gas phase main pipeline, gas phase main pipeline is connected to condenser after passing through breather valve and fire damper, and condenser is connected with exhaust pipe and condensate recovery pipe, and condensate recovery pipe is connected to condensate storage tank;Gas phase main pipeline is also connected with nitrogen main pipe, and coarse adjustment system and fine adjustment system are connected in parallel between nitrogen main pipe and gas phase main pipeline by nitrogen pipe.

[0006] Further, two sets of breather valve and fire damper are connected in parallel between the gas phase main pipeline and the condenser, achieving one standby for one use.

[0007] Further, the condenser is provided with chilled water inlet pipe and chilled water outlet pipe, wherein the gas phase to be condensed flows through shell, and chilled water flows through pipe, and the two flow in opposite directions.

[0008] Further, the nitrogen sealing device further comprises a controller, the coarse adjustment system comprises a coarse adjustment valve, a first pressure gauge and a first orifice plate, wherein the coarse adjustment valve and the first orifice plate are arranged in parallel, and the controller is electrically connected with the first pressure gauge to control the opening and closing of the coarse adjustment valve.

[0009] Further, the fine adjustment system comprises a fine adjustment valve, a second pressure gauge and a second orifice plate, wherein the fine adjustment valve and the second orifice plate are arranged in parallel, and the controller is electrically connected with the second pressure gauge to control the opening and closing of the fine adjustment valve.

[0010] Further, the coarse adjustment valve and the fine adjustment valve are different in diameter, and the diameter of the coarse adjustment valve is larger than that of the fine adjustment valve.

[0011] Further, the pressure range of the first pressure gauge and the second pressure gauge is within the action pressure range of the breather valve.

[0012] Further, the storage tank is filled with volatile organic gas materials.

[0013] The utility model discloses a breather valve is arranged on the gas phase pipeline of each storage tank, and the breather valve is connected with the nitrogen sealing pipeline and the condenser recovery structure, and the breather valve is connected with the nitrogen sealing pipeline and the condenser recovery structure.

[0014] The utility model has the advantages of the following:

[0015] The utility model integrates multiple storage tanks into a set of nitrogen sealing device, and the gas phase pipelines of the multiple storage tanks are connected to the gas phase main pipeline, and the gas phase main pipeline is connected to the nitrogen sealing pipeline and the condenser recovery structure, so that the nitrogen sealing device needs to be installed on each storage tank, and the equipment investment is reduced.

[0016] The device always ensures micro-positive pressure, can avoid air into the system, and has a safety protection measure to ensure the safety of the device when the abnormal low pressure or high pressure condition appears. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 Figure 1 is a structural schematic diagram of the nitrogen sealing device. DETAILED DESCRIPTION

[0018] The embodiments of the present application will be described in detail below with reference to the drawings, but those skilled in the art will understand that the following embodiments are only used to illustrate the present application and should not be regarded as limiting the scope of the present application.

[0019] As shown in Figure 1 The present application provides a nitrogen sealing device, which comprises a plurality of storage tanks 1, each of which is connected to a gas phase branch pipeline 2 at the top, and each gas phase branch pipeline is connected to a gas phase main pipeline 3 after being collected, the gas phase main pipeline is connected to a condenser 6 after passing through a breather valve 4 and a flame arrester 5, the condenser is connected to an exhaust pipe 7 and a condensate recovery pipe 8, and the condensate recovery pipe is connected to a condensate storage tank 9; the gas phase main pipeline is also connected to a nitrogen main pipe 10, and a coarse adjustment system and a fine adjustment system are provided in parallel between the nitrogen main pipe and the gas phase main pipeline through a nitrogen pipe. In the embodiment, the storage tanks are six, but the number of storage tanks in the device is not limited to six; the storage tanks are directly connected by the gas phase branch pipelines, and there are no hand valves, breather valves, flame arresters and other conditions that may cause blockage between the pipelines, so that pressure balance can be formed between them, and the stability of the system is improved.

[0020] In some embodiments, two sets of breather valves and flame arresters are provided in parallel between the gas phase main pipeline and the condenser to achieve one standby and one use. The only contact point between the entire structure and the external atmosphere is the exhaust pipe, and the device contains a flame arrester to prevent external ignition sources from entering the system. The device is sealed at other places, and external air cannot enter the unit, achieving the effect of nitrogen sealing.

[0021] In some embodiments, the condenser is provided with a chilled water inlet pipe and a chilled water outlet pipe, wherein the gas phase to be condensed passes through the shell side, and the chilled water passes through the pipe side, and the two flow in opposite directions.

[0022] In some embodiments, the nitrogen sealing device further comprises a controller, the coarse adjustment system comprises a coarse adjustment valve 11, a first pressure gauge 12 and a first orifice plate 13, wherein the coarse adjustment valve and the first orifice plate are provided in parallel, and the controller is electrically connected to the first pressure gauge to control the opening and closing of the coarse adjustment valve. The controller can be a DSC controller.

[0023] In some embodiments, the fine adjustment system comprises a fine adjustment valve 14, a second pressure gauge 15 and a second orifice plate 16, wherein the fine adjustment valve and the second orifice plate are provided in parallel, and the controller is electrically connected to the second pressure gauge to control the opening and closing of the fine adjustment valve.

[0024] In some embodiments, the diameters of the coarse adjustment valve and the fine adjustment valve are different, and the diameter of the coarse adjustment valve is larger than that of the fine adjustment valve.

[0025] In some embodiments, the pressure range of the first pressure gauge and the second pressure gauge is within the breathing valve action pressure range.

[0026] In some embodiments, the storage tank is filled with volatile organic gas. The volatile organic gas in the plurality of storage tanks is the same type of substance.

[0027] In some cases, the nitrogen main pipe pressure is 0.4 MPa, the breathing valve action pressure is -0.2 KPa to 0.6 KPa, the diameters of the coarse regulating valve and the fine regulating valve are DN65 and DN15, respectively, the coarse regulating valve is set to open or close when the pressure fluctuates within the range of 0.15 KPa to 0.35 KPa according to the display value of the first pressure gauge, and the fine regulating valve is set to open or close when the pressure fluctuates within the range of 0.35 KPa to 0.5 KPa according to the display value of the second pressure gauge. However, the action pressure is not limited to the above values, and other values can also be used.

[0028] In this embodiment, when the nitrogen sealing device pressure is 0.5 KPa, the breathing valve does not act, and the coarse regulating valve and the fine regulating valve do not act. When the material in the storage tank needs to be extracted and material enters the tank, the gas phase pipelines of the storage tanks are connected, the gas phases are balanced, the first pressure gauge and the second pressure gauge slightly fluctuate, and the coarse regulating valve and the fine regulating valve do not act. When the fluctuation in the storage tank causes the flow of the extracted material to increase, the first pressure gauge and the second pressure gauge start to fluctuate and drop, and when the pressure of both drops to 0.35 KPa, the fine regulating valve acts. The second pressure gauge is associated with the fine regulating valve, and after the fine regulating valve is opened, nitrogen enters the nitrogen sealing device, and at this time the pressure rises to 0.45 KPa, meeting the normal operating pressure condition. When the fluctuation in the storage tank causes the inflow of material to increase, the first pressure gauge and the second pressure gauge continue to rise, and when the pressure of both rises to 0.5 KPa, the fine regulating valve acts to close. Nitrogen stops entering the nitrogen sealing device. When the pressure abnormally rises to 0.6 KPa, the breathing valve acts, the organic gas enters the condenser for condensation and recovery, is recovered to the condensate storage tank through the condensate recovery pipe, and the incondensable gas is discharged through the exhaust pipe of the condenser. When the fluctuation in the storage tank causes the flow of the extracted material to continue to increase, the first pressure gauge and the second pressure gauge start to fluctuate and drop, and when the pressure of both drops to 0.15 KPa, the coarse regulating valve acts. The first pressure gauge is associated with the coarse regulating valve, and after the coarse regulating valve is opened, nitrogen enters the nitrogen sealing device, and at this time the pressure rises to more than 0.35 KPa, and the coarse regulating valve closes. When the pressure abnormally drops to -0.2 KPa, the breathing valve acts, and the external gas enters the nitrogen sealing system through the exhaust pipe and then the breathing valve, avoiding damage to the tank due to negative pressure in the nitrogen sealing device.

[0029] The above embodiment describes the preferred embodiment of the present application, but the present application is not limited thereto. Within the technical concept of the present application, various simple modifications can be made to the technical solution of the present application, including the combination of various technical features in any other manner. These simple modifications and combinations should also be considered as disclosed by the present application, and belong to the protection scope of the present application. Therefore, the protection scope of the present application patent should be subject to the appended claims.

Claims

1. A nitrogen sealing device characterized by: The device comprises a plurality of storage tanks, each of which is connected to a gas phase branch pipe at the top, and each gas phase branch pipe is connected to a gas phase main pipe, the gas phase main pipe is connected to a condenser through a breather valve and a flame arrester, the condenser is connected to an exhaust pipe and a condensate recovery pipe, the condensate recovery pipe is connected to a condensate storage tank; the gas phase main pipe is also connected to a nitrogen main pipe, and a coarse adjustment system and a fine adjustment system are connected in parallel between the nitrogen main pipe and the gas phase main pipe through a nitrogen pipe.

2. The apparatus of claim 1, wherein: Two sets of breather valves and flame arresters are connected in parallel between the gas phase main pipe and the condenser to realize one standby and one use.

3. The apparatus of claim 1, wherein: The condenser is provided with a chilled water inlet pipe and a chilled water outlet pipe, wherein the gas phase to be condensed passes through the shell side, and the chilled water passes through the pipe side, and the two flow in opposite directions.

4. The apparatus of claim 1, wherein: The nitrogen sealing device further comprises a controller, the coarse adjustment system comprises a coarse adjustment valve, a first pressure gauge and a first orifice plate, wherein the coarse adjustment valve and the first orifice plate are connected in parallel, and the controller is electrically connected to the first pressure gauge to control the opening and closing of the coarse adjustment valve.

5. The apparatus of claim 4, wherein: The fine adjustment system comprises a fine adjustment valve, a second pressure gauge and a second orifice plate, wherein the fine adjustment valve and the second orifice plate are connected in parallel, and the controller is electrically connected to the second pressure gauge to control the opening and closing of the fine adjustment valve.

6. The apparatus of claim 5, wherein: The diameters of the coarse adjustment valve and the fine adjustment valve are different, and the diameter of the coarse adjustment valve is larger than that of the fine adjustment valve.

7. The apparatus of claim 6, wherein: The pressure ranges of the first pressure gauge and the second pressure gauge are within the action pressure range of the breather valve.

8. The apparatus of claim 1, wherein: The storage tank is filled with volatile organic gas materials.

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