Storage tank device
By installing a pressure feedback device and DCS system on the top of the tank, the problem of tank pressure control lag caused by the self-operated regulating valve pressure-guiding method was solved, and precise regulation and stabilization of the tank pressure was achieved, reducing exhaust emissions and improving safety and reliability.
Patent Information
- Application Number
- CN202520714000.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-15
- Publication Date
- 2025-09-12
- Estimated Expiration
- 2035-04-15
AI Technical Summary
The pressure-guiding method of the self-operated regulating valve causes a delayed response of the tank pressure control, especially when the weather and environment change suddenly, resulting in unstable tank pressure, increased unnecessary exhaust emissions, and affecting the safety and operational reliability of the tank.
A pressure feedback device on the top of the tank is used to monitor the pressure in real time and communicate wirelessly with the pressure control valve through a distributed control system (DCS), replacing the self-operated regulating valve for precise control. The air seal pipeline and pressure-compensating gas source are used to maintain a stable pressure in the tank.
It achieves precise control of tank pressure, reduces unnecessary exhaust emissions, improves tank operation reliability and safety, and ensures long-term stable operation.
Smart Images
Figure CN223331523U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of storage tank pressure control. Background Art
[0002] In the petrochemical, pharmaceutical, and energy sectors, storage tanks are essential equipment for storing liquid or gaseous materials. Due to their flammability, explosiveness, and oxidation sensitivity, these materials often require the use of an inert gas, typically nitrogen. Nitrogen is injected into the tank's gas phase to maintain a slight positive pressure, isolating oxygen and stabilizing the pressure. The stability of tank pressure directly impacts production safety, material quality, and environmental protection. Inaccurate pressure control can cause tank deformation or overpressure leaks. However, changes in ambient temperature can cause changes in the volume of liquid or gas stored within the tank, resulting in pressure fluctuations within the tank. In recent years, self-operated regulating valves, as pressure control devices that require no external power source, have become widely used in tank pressure control. They rely on the pressure of the medium flowing through the valve as feedback to balance the pressures on both sides of the diaphragm, automatically controlling the valve opening to stabilize the downstream pressure. Requiring no external power supply or secondary instrumentation, they feature a simple structure, low cost, and reliable operation. For self-operated regulating valves, their position and mounting method directly affect the accuracy of the pressure signal, which in turn affects the valve's response speed and system stability. However, due to concerns about the health and safety of maintenance personnel, self-operated regulating valves cannot usually be installed on the platform on top of the tank or at a location close to the tank. Instead, they need to be installed on the pipeline platform. In actual production, especially for larger tanks, the self-operated regulating valve installed on the pipeline platform is often located a certain distance away from the tank. As a result, the pressure reference point on the self-operated regulating valve cannot directly reference the tank pressure for feedback control, causing the self-operated regulating valve to have a large response lag to changes in tank pressure, resulting in insensitive pressure control and insufficient regulation accuracy. Especially in the event of sudden changes in weather conditions, this can cause the tank pressure to be too low or too high for a long time, thereby increasing the tank's exhaust emissions and affecting the tank's safety. Utility Model Content
[0003] In response to the problems of delayed pressure control response caused by the pressure-guiding method of the self-operated regulating valve in actual production, the utility model aims to provide a storage tank device, which achieves precise control of the tank pressure by using a new pressure control method to replace the self-operated regulating valve.
[0004] The storage tank device of the present invention includes a tank body, a storage tank pressure feedback device, an air sealing pipeline, a pressure control valve, and a pressure-compensating air source. The storage tank pressure feedback device is arranged on the top of the tank body, the input end of the air sealing pipeline is connected to the pressure-compensating air source, and the output end is connected to the top of the tank body. The pressure control valve is arranged on the air sealing pipeline.
[0005] The tank pressure feedback device is mounted on the top of the tank body and is used to monitor the pressure in the tank body in real time and generate a feedback signal. The generated feedback signal is transmitted to the pressure control valve disposed on the airtight pipeline. In some examples, the tank pressure feedback device is wirelessly connected to the pressure control valve via a control system, preferably a distributed control system (DCS).
[0006] In some examples, the pressure control valve is a pneumatic regulating valve or an electric regulating valve.
[0007] In some examples, the tank pressure feedback device includes a pressure transmitter, a pressure sensor, or a transmission cable.
[0008] In some examples, the pressure-compensating gas source is used to supply an inert gas, preferably nitrogen, into the tank through the gas sealing line.
[0009] The utility model transforms the pressure-inducing method of the self-operated regulating valve, directly adopts the real-time pressure transmitted from the top of the storage tank as the pressure control point, and realizes precise control of the storage tank pressure through a control system such as a DCS using a pressure control valve, thereby eliminating unnecessary exhaust emission losses caused by insensitive pressure control of the storage tank, and at the same time increasing the normal operation reliability of the storage tank, thereby ensuring the long-term stable operation of the device. BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Figure 1 It is a structural schematic diagram of a storage tank device according to one embodiment of the present utility model. DETAILED DESCRIPTION
[0011] The structure of the storage tank device of the present invention is further described in detail below with reference to the accompanying drawings. It should be understood that the embodiments described herein are only used to illustrate and explain the present invention and are not used to limit the scope of the present invention.
[0012] like Figure 1As shown, the storage tank device according to the present invention includes a tank body 1, an air-sealing pipeline 2, a storage tank pressure feedback device 3, a pressure control valve 4 and a pressure-compensating gas source 5. The pressure control valve 4 is arranged on the air-sealing pipeline 2. At least part of the air-sealing pipeline 2 passes above a pipeline platform at a certain horizontal distance from the tank body 1. The horizontal distance between the pipeline platform and the top of the tank body 1 can be determined according to the pipeline layout and operation requirements (for example, 3-20m, or 5-10m). The storage tank pressure feedback device 3 is arranged at the top of the tank body 1. The input end and output end of the air-sealing pipeline 2 are connected to the pressure-compensating gas source 5 and the top of the tank body 1, respectively. In some embodiments, the pressure-compensating gas source 5 can be a pressurized gas storage tank or a gas compressor, which provides an inert gas with a pressure higher than the normal pressure of the tank body 1. In some embodiments, the pressure control valve 4 is located at a position where the air-sealing pipeline 2 is located above the pipeline platform and the horizontal distance from the nearest edge of the top of the tank body 1 is greater than 3m, for example, 3-20m, or 5-10m.
[0013] The tank body 1 can store media that require nitrogen gas sealing to avoid contact with air, but is not suitable for media that must be in contact with air. The pressure compensation gas source 5 is used to supply an inert gas such as nitrogen to the top gas phase space in the tank body 1 through the gas sealing pipeline 2. The tank pressure feedback device 3 is set at the top of the tank body 1 so that the actual pressure in the tank can be accurately detected in real time and a feedback signal (such as Figure 1 The generated feedback signal is transmitted to the controller of the distributed control system (DCS). The DCS controller processes the input signal using a control algorithm such as PID and outputs a control command to the pressure control valve 4 to activate and deactivate the pressure control valve and adjust its valve opening. The pressure control valve 4 can adjust the nitrogen flow rate to maintain the set pressure according to the control command of the DSC.
[0014] The pressure control valve 4 is arranged at a position above the pipeline platform of the air sealing line, at a certain horizontal distance from the tank body 1 (for example, greater than 3m, such as 5-20m, and another example of 5-10m), avoiding being directly arranged above the tank body, thereby facilitating the laying of instrument gas pipes and cables, and when the valve needs to be repaired, it can be kept away from the on-site discharge point of the tank top breathing valve, avoiding being affected by the volatile gas in the tank during the normal discharge of the breathing valve. In some embodiments, the pressure control valve 4 and the breathing valve 7 are located on the opposite side of the top center of the tank body 1 relative to the top center of the tank body 1, so as to maximize the distance between the maintenance personnel and the breathing valve 7 when operating the pressure control valve 4. For example, when the top of the storage tank 1 is circular, the angle between the pressure control valve 4 and the breathing valve 7 relative to the center of the circle is greater than 90°, preferably greater than 120°. In some embodiments, the storage tank device includes a plurality of tank bodies 1, and each tank body 1 corresponds to its own air sealing line 2, storage tank pressure feedback device 3, and pressure control valve 4, and the respective air sealing lines 2 can be commonly connected to the same pressure-compensating gas source 5. In this case, the pipeline platform can be located between the tops of multiple tanks (not shown) arranged side by side. In this case, maintenance personnel can perform maintenance operations on the pressure control valves 4 on the airtight pipelines corresponding to the multiple tanks located above the pipeline platform on the pipeline platform, thereby avoiding the need to climb over the multiple tanks and reducing the risk of personal injury.
[0015] In some embodiments, the tank pressure feedback device 3 is a pressure transmitter, a pressure sensor, or a transmission cable. In some embodiments, the pressure control valve 4 is a pneumatic control valve or an electric control valve. Specifically, a pressure transmitter, for example, is used to measure the tank pressure in real time and output a standardized electrical signal to the DCS. When, for example, the ambient temperature drops, causing the tank pressure to drop, the pressure transmitter detects that the tank pressure is below the set value. The DCS then increases the valve opening of a pressure control valve, such as a pneumatic control valve, to replenish nitrogen to increase the pressure. When the ambient temperature rises, causing the tank pressure to rise, the pressure transmitter detects that the pressure exceeds the upper limit. The pressure control valve closes, and the pressure relief valve 6 located at the top of the tank opens, venting gas to a flare system or exhaust gas treatment device to reduce the pressure. Additionally, one or more breather valves 7 can be installed at the top of the tank as redundant protection, opening and closing during extreme pressure fluctuations. For example, if the pressure control valve 4 is near its maximum opening and the gas from the boost gas source 5 is unable to effectively raise the tank pressure to normal or is increasing too slowly, one or more breather valves 7 can open and draw in air to prevent the tank from collapsing.
[0016] The storage tank device of the utility model adopts a pressure feedback device directly installed on the top of the storage tank as the pressure monitoring point, which ensures the accuracy and timeliness of the storage tank pressure signal, and replaces the self-operated regulating valve with a pressure control valve arranged above the pipeline platform at a certain distance from the top of the tank body, and realizes precise control and adjustment of the storage tank pressure through the DCS, while meeting the health and safety requirements of maintenance personnel.
[0017] The above is only a description of the preferred embodiment of the present invention. Without departing from the spirit and essence of the present invention, technicians familiar with the field can make various corresponding modifications and variations based on the present invention. These modifications and variations are all within the scope of the claims required to be protected by the present invention.
Claims
1. A storage tank device, comprising a tank body, a storage tank pressure feedback device, an air sealing pipeline, a pressure control valve, and a pressure compensation gas source, characterized in that: The tank pressure feedback device is arranged at the top of the tank body, the input end of the air sealing pipeline is connected to the pressure-compensating air source, and the output end is connected to the top of the tank body. The pressure control valve is arranged on the air sealing pipeline, wherein the pressure control valve is a pneumatic regulating valve or an electric regulating valve. The tank pressure feedback device is wirelessly connected to the pressure control valve through a distributed control system DCS. The pressure control valve is located at a position above the pipeline platform on the air sealing pipeline, and the minimum horizontal distance between the pipeline platform and the top of the tank body is greater than 3m.
2. The storage tank device according to claim 1, characterized in that The storage tank pressure feedback device includes a pressure transmitter, a pressure sensor or a transmission cable.
3. The storage tank device according to claim 1 or 2, characterized in that: The pressure-compensating gas source is used to supply nitrogen into the tank through the gas sealing pipeline.
4. The storage tank device according to claim 1, characterized in that The storage tank device further includes a breathing valve located at the top of the tank body, and the pressure control valve and the breathing valve are located on opposite sides of the top center of the tank body.