High-temperature oil gas storage tank

Abstract

A high-temperature oil gas storage tank comprises a storage tank, the upper portion of the storage tank is connected with a buffer tank, a partition plate is arranged in the buffer tank and divides a cavity in the buffer tank into a first buffer cavity and a second buffer cavity, a through pipe is arranged on the partition plate, and the first buffer cavity and the second buffer cavity are communicated through the through pipe; a nitrogen pressure supplementing pipe is arranged at the lower part of the buffer tank and is communicated with the first buffer cavity; an oil-gas pressure relief pipe is arranged at the lower part of the buffer tank, a concentric-square-shaped pipe is arranged in the first buffer cavity, the oil-gas pressure relief pipe is communicated with the concentric-square-shaped pipe, a nitrogen return pipe is arranged at the other end of the concentric-square-shaped pipe, and the concentric-square-shaped pipe is communicated with the second buffer cavity through the nitrogen return pipe; multi-stage pressure gradient diffusion is adopted for oil gas recovery of the storage tank, so that sudden pressure relief of the storage tank due to too high pressure and too fast pressure drop of the storage tank can be reduced; pressure stability of the storage tank can be guaranteed, the phenomenon that the oil gas volatilization amount is increased due to sudden pressure drop of the storage tank is reduced, the storage tank reaches a pressure balance state, and normal and stable operation of the device after follow-up oil gas recovery is guaranteed.

Description

Technical Field

[0001] The utility model relates to the technical field of oil and gas recovery, and more specifically to a high-temperature oil and gas storage tank. Background Art

[0002] At present, in the production and storage and transportation fields such as petrochemical, coal chemical, and organic chemical industries, the storage applications of various raw materials, intermediate products, and organic liquid products in atmospheric or low-pressure storage tanks are very extensive. The most commonly used storage tank types are atmospheric or low-pressure storage dome tanks and floating roof tanks (internal floating roof tanks), etc. For some oil products or chemical liquid products, or their intermediate products, oxidation reactions may occur when they come into contact with air during storage. Sometimes people are worried that the air in the gas phase space above the tank will affect storage safety. In this case, the nitrogen sealing process is often used. The nitrogen sealing process of the existing technology is to connect a nitrogen pipeline from the gas phase space above the tank, and form a pressure control loop with the nitrogen sealing regulating valve on the nitrogen pipeline through the pressure transmitter on the tank top. When the pressure in the gas phase space of the storage tank is lower than the atmospheric pressure, before the breathing valve on the tank top inhales air, the nitrogen sealing regulating valve opens to supplement nitrogen into the storage tank, so that an oxygen-free atmosphere is formed in the gas phase space of the storage tank. When the pressure on the tank top is higher than the set pressure for exhalation of the breathing valve, the gas in the tank is discharged from the breathing valve. With the increasing environmental pressure, the increasing awareness of environmental protection among people, and the increasing scope and strictness of environmental protection regulations, the environmental protection problems caused by the organic matter emissions of the storage tank oil and gas are getting more and more attention, and the recovery and treatment of the storage tank oil and gas gradually become a trend. At the same time, due to the unreasonable design of the processing capacity of the oil and gas recovery system, the operation of the oil and gas recovery system is in a severe alternating state, which exacerbates the fatigue of the equipment and has a high safety risk. Summary of the Invention

[0003] To solve the above problems and overcome the deficiencies of the prior art, the utility model provides a high-temperature oil and gas storage tank.

[0004] To achieve the above object, a high-temperature oil and gas storage tank provided by the utility model includes a storage tank, a buffer tank is connected to the upper part of the storage tank, a partition is arranged in the buffer tank, the partition divides the cavity in the buffer tank into a first buffer cavity and a second buffer cavity, a through pipe is arranged on the partition, and the first buffer cavity and the second buffer cavity are communicated by the through pipe;

[0005] A nitrogen pressure supplement pipe is arranged at the lower part of the buffer tank, and the nitrogen pressure supplement pipe is communicated with the first buffer cavity;

[0006] An oil and gas pressure relief pipe is arranged at the lower part of the buffer tank, a return pipe is arranged inside the first buffer cavity, the oil and gas pressure relief pipe is communicated with the return pipe, and the other end of the return pipe is provided with a nitrogen return pipe, and the return pipe is communicated with the second buffer cavity through the nitrogen return pipe;

[0007] A nitrogen pressure supplement port and an oil and gas pressure relief port are connected to the second buffer cavity;

[0008] The nitrogen make-up port is connected to a pressure-stabilizing nitrogen pipeline, and the oil and gas pressure-relief port is connected to an oil and gas recovery pipeline.

[0009] Furthermore, a second breather valve is connected to the upper part of the buffer tank. The inlet of the second breather valve is connected to the pressure-stabilizing nitrogen pipeline, and the outlet of the second breather valve is connected to the oil and gas recovery pipeline.

[0010] Furthermore, the pressure-stabilizing nitrogen pipeline includes a nitrogen pipeline, on which an automatic control regulating valve and a self-acting regulating valve are arranged.

[0011] Furthermore, the oil and gas recovery pipeline includes a recovery pipeline, on which a self-acting regulating valve is arranged.

[0012] Furthermore, a first breather valve is also arranged on the upper part of the storage tank, and the first breather valve is directly connected to the atmosphere.

[0013] Furthermore, the lower part of the storage tank is connected with an inlet pipe and an outlet pipe.

[0014] Furthermore, both the oil and gas pressure-relief pipe and the nitrogen make-up pipe are communicated with the storage tank.

[0015] The beneficial effects of the present utility model are as follows:

[0016] It can stabilize the operation of the oil and gas recovery device, reduce the design load of the oil and gas recovery device, reduce equipment fatigue, and reduce safety risks. It improves the sealing performance of the storage tank, which can not only reduce the overflow of VOCs gas from the storage tank, but also meet the relevant national safety standards to ensure the safe and stable operation of the storage tank. An independent nitrogen make-up system with independent control is set for the pressure-stabilizing nitrogen of each storage tank. Through safety measures such as nitrogen make-up, oil and gas recovery, and overpressure discharge, the safety of the storage tank system is guaranteed, and the nitrogen consumption and the investment of the nitrogen sealing system are reduced.

[0017] Through the oil and gas recovery graded pressure relief and pressure-stabilizing nitrogen graded nitrogen make-up system of the storage tank, the oil and gas recovery of the storage tank adopts multi-stage pressure gradient release, which can reduce the sudden pressure relief of the storage tank due to too high pressure and the too fast drop of the storage tank pressure. It can not only ensure the pressure stability of the storage tank, reduce the phenomenon of increased oil and gas volatilization due to the sudden drop of the storage tank pressure, make the oil and gas volume stable, reduce the material loss, make the storage tank reach a pressure balance state, ensure the normal and stable operation of the subsequent oil and gas recovery device, avoid the frequent and large-amplitude alternating operation of the oil and gas recovery device, and make the VOCs emission value meet the environmental protection emission standard requirements. It can also ensure the safety of the storage tank system and prevent the occurrence of overpressure damage or negative pressure suction accidents of the storage tank. Description of the Drawings

[0018] Attached Figure 1 is the structure diagram of the present utility model;

[0019] Attached Figure 2 is the structure diagram of the buffer tank of the present utility model

[0020] Among them, the reference numerals are as follows:

[0021] 1. Storage tank, 2. Inlet pipe, 3. Outlet pipe, 4. First breathing valve, 5. Buffer tank, 6. Second breathing valve, 7. Pressure-stabilizing nitrogen pipeline, 8. Oil and gas recovery pipeline;

[0022] 51. Oil and gas pressure relief pipe, 52. Nitrogen make-up port, 53. Return pipe, 54. Nitrogen return pipe, 55. First buffer chamber, 56. Connecting pipe, 57. Second buffer chamber, 58. Oil and gas pressure relief port, 59. Nitrogen make-up pipe. Detailed implementation mode

[0023] To make the purpose, technical solution and advantages of the implementation of the present utility model clearer, the following will combine the attached drawings of the present utility model Figure 1 and the attached drawings Figure 2 to describe the present utility model in more detail.

[0024] A high-temperature oil and gas storage tank 1 provided by the present utility model includes a storage tank 1. A buffer tank 5 is connected to the upper part of the storage tank 1. A partition is arranged in the buffer tank 5, and the partition divides the cavity in the buffer tank 5 into a first buffer chamber 55 and a second buffer chamber 57. A connecting pipe 56 is arranged on the partition, and the first buffer chamber 55 and the second buffer chamber 57 are communicated by the connecting pipe 56; a nitrogen make-up pipe 59 is arranged at the lower part of the buffer tank 5, and the nitrogen make-up pipe 59 is communicated with the first buffer chamber 55; an oil and gas pressure relief pipe 51 is arranged at the lower part of the buffer tank 5. A return pipe 53 is arranged inside the first buffer chamber 55, and the oil and gas pressure relief pipe 51 is communicated with the return pipe 53. The other end of the return pipe 53 is provided with a nitrogen return pipe 54, and the return pipe 53 is communicated with the second buffer chamber 57 through the nitrogen return pipe 54; a nitrogen make-up port 52 and an oil and gas pressure relief port 58 are connected to the second buffer chamber 57; the nitrogen make-up port 52 is connected with a pressure-stabilizing nitrogen pipeline 7, and the oil and gas pressure relief port 58 is connected with an oil and gas recovery pipeline 8; a second breathing valve 6 is connected to the upper part of the buffer tank 5. The inlet of the second breathing valve 6 is connected to the pressure-stabilizing nitrogen pipeline 7, and the outlet of the second breathing valve 6 is connected to the oil and gas recovery pipeline 8; the pressure-stabilizing nitrogen pipeline 7 includes a nitrogen pipeline, and an automatic control regulating valve and a self-operated regulating valve are arranged on the nitrogen pipeline; the oil and gas recovery pipeline 8 includes a recovery pipeline, and a self-operated regulating valve is arranged on the recovery pipeline; a first breathing valve 4 is also arranged on the upper part of the storage tank 1, and the first breathing valve 4 is directly connected to the atmosphere; an inlet pipe 2 and an outlet pipe 3 are connected to the lower part of the storage tank 1; both the oil and gas pressure relief pipe 51 and the nitrogen make-up pipe 59 are communicated with the storage tank 1.

[0025] The first embodiment is as follows:

[0026] A high-temperature oil and gas storage tank 1, including the storage tank 1, a buffer tank 5 is connected to the upper part of the storage tank 1. A partition is arranged in the buffer tank 5, and the partition divides the cavity in the buffer tank 5 into a first buffer cavity 55 and a second buffer cavity 57. A through pipe 56 is arranged on the partition, and the first buffer cavity 55 and the second buffer cavity 57 are communicated by the through pipe 56. The first buffer tank 5 and the second buffer tank 5 form a two-stage buffer structure and are communicated through the through pipe 56.

[0027] In addition, two lines are formed in the buffer tank 5, namely a nitrogen supplement line and an oil and gas pressure relief line.

[0028] The nitrogen supplement line includes a nitrogen pressure supplement port 52, the first buffer cavity 55, the through pipe 56, the second buffer cavity 57 and a nitrogen pressure supplement pipe 59. The nitrogen pressure supplement port 52 is connected to a regulated nitrogen gas pipeline 7. The regulated nitrogen gas pipeline 7 includes a nitrogen gas pipeline, and an automatic control regulating valve and a self-acting regulating valve are arranged on the nitrogen gas pipeline. The regulated nitrogen gas adopts a control mode combining the automatic control regulating valve and the self-acting regulating valve. The pressure after the automatic control regulating valve is 0.1 - 0.2 MPa. The set pressure of the self-acting regulating valve is 0.3 - 0.5 KPa. When the pressure in the storage tank 1 is lower than 0.3 KPa, the self-acting regulating valve automatically opens to supplement nitrogen to the storage tank 1; when the pressure in the storage tank 1 is higher than 0.5 KPa, the self-acting regulating valve automatically closes to stop nitrogen supplementation.

[0029] The oil and gas pressure relief line includes an oil and gas pressure relief pipe 51, a return pipe 53, a nitrogen return pipe 54, the second buffer cavity 57 and an oil and gas pressure relief port 58; the return pipe 53 is arranged, which can lengthen the length of the nitrogen delivery pipeline, reduce the occupied space, reduce the nitrogen treatment amount. At the same time, when the pressure is high, by arranging the return pipe 53, it can ensure that the pressure in the storage tank 1 drops slowly and evenly, which can not only ensure the pressure stability of the storage tank 1, reduce the phenomenon of increased oil and gas volatilization due to the sudden drop of the pressure in the storage tank 1, keep the oil and gas volume stable, reduce the material loss, make the storage tank 1 reach a pressure balance state, ensure the normal and stable operation of the subsequent oil and gas recovery device, avoid the frequent and large-amplitude alternating operation of the oil and gas recovery device, and make the VOCs emission value meet the environmental protection discharge standard requirements. It can also ensure the safety of the storage tank 1 system and prevent the occurrence of overpressure damage or negative pressure suction and collapse accidents of the storage tank 1.

[0030] An oil and gas pressure relief pipe 51 is provided at the lower part of the buffer tank 5. A return pipe 53 is arranged inside the first buffer chamber 55. The oil and gas pressure relief pipe 51 is communicated with the return pipe 53. The other end of the return pipe 53 is provided with a nitrogen return pipe 54. The return pipe 53 is communicated with the second buffer chamber 57 through the nitrogen return pipe 54. A nitrogen make-up port 52 and an oil and gas pressure relief port 58 are connected to the second buffer chamber 57. The oil and gas pressure relief port 58 is connected with an oil and gas recovery pipeline 8. The oil and gas recovery pipeline 8 includes a recovery pipeline, and a self-operated regulating valve is arranged on the recovery pipeline. When the pressure of the storage tank 1 is higher than 0.8 KPa, the self-operated regulating valve automatically opens to relieve pressure to the oil and gas recovery device. When the pressure is lower than 0.5 KPa, the self-operated regulating valve automatically closes to stop relieving pressure to the oil and gas recovery device.

[0031] The upper part of the buffer tank 5 is connected with a second breather valve 6. The inlet of the second breather valve 6 is connected with a regulated nitrogen pipeline 7. The outlet of the second breather valve 6 is connected with the oil and gas recovery pipeline 8. The set pressure of the breather valve is -0.29 / 0.98 KPa. When the pressure is higher than 0.98 KPa, the breather valve relieves pressure to the oil and gas recovery device. When the storage tank 1 is lower than -0.29 KPa, nitrogen is supplemented to the storage tank 1.

[0032] A first breather valve 4 is further arranged at the upper part of the storage tank 1. The first breather valve 4 is directly connected to the atmosphere, and the set pressure is -0.39 / 1.75 KPa.

[0033] The oil and gas recovery of the storage tank 1 and the regulated nitrogen pipeline 7 perform staged pressure relief and nitrogen supplementation, which can not only ensure the stable pressure of the storage tank 1, reduce the increase in the volatilization amount of oil and gas due to the sudden drop in the pressure of the storage tank 1, keep the amount of oil and gas stable, ensure the normal and stable operation of the subsequent oil and gas recovery device, but also ensure the safe and stable operation of the storage tank 1.

[0034] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A high-temperature oil and gas storage tank, comprising a storage tank, characterized in that: The upper part of the storage tank is connected to a buffer tank, a partition is arranged in the buffer tank, the partition divides the cavity in the buffer tank into a first buffer cavity and a second buffer cavity, a through pipe is arranged on the partition, and the first buffer cavity and the second buffer cavity are connected by the through pipe; A nitrogen pressure boosting pipe is provided at the lower part of the buffer tank, and the nitrogen pressure boosting pipe is communicated with the first buffer chamber; An oil and gas pressure relief pipe is provided at the lower part of the buffer tank, a return pipe is provided inside the first buffer cavity, the oil and gas pressure relief pipe is connected with the return pipe, a nitrogen return pipe is provided at the other end of the return pipe, and the return pipe is connected with the second buffer cavity through the nitrogen return pipe; The second buffer chamber is connected with a nitrogen pressure replenishment port and an oil and gas pressure relief port; The nitrogen pressure replenishing port is connected to a pressure-stabilizing nitrogen pipeline, and the oil and gas pressure relief port is connected to an oil and gas recovery pipeline.

2. The high-temperature oil and gas storage tank according to claim 1, characterized in that: The upper part of the buffer tank is connected with a second breathing valve, the inlet of the second breathing valve is connected to a pressure-stabilizing nitrogen pipeline, and the outlet of the second breathing valve is connected to an oil and gas recovery pipeline.

3. The high-temperature oil and gas storage tank according to any one of claims 1 or 2, characterized in that: The pressure-stabilized nitrogen pipeline comprises a nitrogen pipeline, on which an automatic control regulating valve and a self-operated regulating valve are arranged.

4. The high-temperature oil and gas storage tank according to any one of claims 1 or 2, characterized in that: The oil and gas recovery pipeline comprises a recovery pipeline, and a self-operated regulating valve is arranged on the recovery pipeline.

5. The high-temperature oil and gas storage tank according to claim 1, characterized in that: A first breathing valve is also provided on the upper portion of the storage tank, and the first breathing valve is directly connected to the atmosphere.

6. The high-temperature oil and gas storage tank according to claim 1, characterized in that: The lower part of the storage tank is connected with an inlet pipe and an outlet pipe.

7. The high-temperature oil and gas storage tank according to claim 1, characterized in that: The oil and gas pressure relief pipe and the nitrogen pressure supplement pipe are both connected to the storage tank.

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