CN112197170A

CN112197170A - Low temperature storage tank interface valve group system of LNG vaporizing station

Info

Publication number: CN112197170A
Application number: CN202011141068.3A
Authority: CN
Inventors: 宋朋飞; 庞璐; 刘芷含; 王振宇
Original assignee: Changchun Gas Thermal Design And Research Institute Co ltd
Current assignee: Changchun Gas Thermal Design And Research Institute Co ltd
Priority date: 2020-10-22
Filing date: 2020-10-22
Publication date: 2021-01-08

Abstract

A low-temperature storage tank interface valve group system of an LNG (liquefied natural gas) gasification station is characterized by comprising a liquid inlet main pipe part and a liquid outlet main pipe part, wherein the liquid inlet main pipe part comprises two branches, one branch is connected with a pressurization liquid inlet pipe of an LNG storage tank, a valve (4) is arranged on the liquid inlet main pipe of the storage tank pressurization and connected to a connector (B), the other branch is provided with a starting emergency cut-off valve (3), the valve (3) is provided with ZSOV and VIC, a valve (1) and a valve (2) are arranged at the downstream of the valve (3) and respectively communicated with an upper liquid inlet main pipe and a lower liquid inlet main pipe of the storage tank and connected to a connector (C) and a connector (D), the connector (C) is connected with an upper; the gas phase pipe is connected with a gas phase port of the storage tank through a connector (E), the gas phase pipe is a bidirectional vent pipe, and a gas inlet pipe in the gas inlet direction is connected with the connector (E) and the storage tank through a connector (I) connected with a supercharger of the storage tank, is provided with a valve (7) at the downstream of the connector (I), and is then connected with the connector (E) and connected with the storage tank.

Description

Low temperature storage tank interface valve group system of LNG vaporizing station

Technical Field

The invention relates to a low-temperature storage tank interface valve group system of an LNG (liquefied natural gas) gasification station, belonging to the field of control systems of LNG gasification stations.

Background

At present, inlet and outlet pipelines of a storage tank in a conventional LNG gasification station are criss-cross, the horizontal width of the pipeline in a tiled mode is between 1000 mm-1400 mm, the valve is difficult to operate, the pipeline needs to be independently made to span a ladder, the overall attractiveness is affected, and potential safety hazards exist.

Disclosure of Invention

In order to solve the defects and shortcomings, the invention provides a low-temperature storage tank interface valve group system of an LNG gasification station.

The technical scheme adopted by the invention for solving the technical problem is as follows:

a low-temperature storage tank interface valve group system of an LNG gasification station is characterized by comprising a liquid inlet main pipe part and a liquid outlet main pipe part, wherein the liquid inlet main pipe part comprises two branches, one branch is connected with a pressurization liquid inlet pipe of an LNG storage tank, a valve 4 is arranged on the liquid inlet main pipe of a storage tank pressurizer and connected to a port B, the other branch is provided with a starting emergency cut-off valve 3, a ZSOV and a VIC are arranged at the valve 3, a valve 1 and a valve 2 are arranged at the downstream of the valve 3 and respectively communicated to an upper liquid inlet main pipe and a lower liquid inlet main pipe of the storage tank and connected to a port C and a port D, the port C is connected with an upper; the gas phase pipe is connected with a gas phase port of the storage tank through a connector E, the gas phase pipe is a bidirectional vent pipe, a gas inlet pipe in the gas inlet direction passes through a connector I connected with a storage tank supercharger, a valve 7 is arranged at the downstream of the connector I and then connected to the connector E and connected with the storage tank, a valve 8, a valve 9, a valve 10 and a valve 11 are arranged in the gas outlet direction, the valve 8 is a bypass passage formed by combining the valve 9, the valve 10 and the valve 11, namely the valve 8, the valve 9, the valve 10 and the valve 11 are combined in parallel, the valve 11 is a pressure detection valve, and if the pressure is higher than a set value, the valve 11 is automatically opened and is connected with a BOG pipeline through a connector J; the interface F connects the liquid outlet pipe with the liquid outlet of the storage tank, an emergency cut-off valve 5 is arranged at the downstream of the liquid outlet pipe, the valve 5 is a starting valve, ZOV and VIC are arranged at the position of the valve 5, a valve 6 is arranged at the downstream of the valve 5, the valve 6 is a manual valve and is then connected with an interface H, and the interface H leads to a liquid outlet main pipe; the safety valve group 21 is arranged at the upstream of the emergency cut-off valve 3 of the liquid inlet main pipe, the safety valve group 21 is opened when the pipeline pressure is higher than a set value, a small amount of low-temperature liquid enters a bleeding pipe, and the bleeding pipe is connected with a bleeding main pipe through a connector G; a safety valve group 22 is arranged between the valve 3 and the valves 1 and 2, when the pipeline pressure is higher than a set value, the safety valve group 22 is opened, a small amount of low-temperature liquid enters a diffusing pipe, and the diffusing pipe is connected with a diffusing main pipe through a connector G; a safety valve group 23 is arranged between the valve 5 and the valve 6, when the pipeline pressure is higher than a set value, the safety valve group 23 is opened, a small amount of low-temperature liquid enters a diffusing pipe, and the diffusing pipe is connected with a diffusing main pipe through a connector G; a plurality of safety valve groups connected in parallel are arranged at the downstream of the gas-phase pipe, when the pressure of the gas-phase pipe is higher than a set value, the plurality of safety valve groups are simultaneously opened, redundant gas is discharged into the bleeding pipe and is connected with the bleeding main pipe through a connector G, and if one of the safety valve groups fails, the other safety valve groups can still ensure normal work and system safety.

A control method of a low-temperature storage tank interface valve block system of an LNG gasification station is characterized in that when the pressure in a pipeline is higher than a set value of a safety valve, a safety valve block 21 is opened, and a small amount of low-temperature liquid enters a diffusing and collecting pipe through the safety valve block 21 and is collected to a valve block prying interface G; because LNG in the middle sealed pipe section is naturally gasified when the pneumatic emergency cut-off valve 3 and the manual stop valves 1 and 2 are closed simultaneously, the pressure in the pipeline can reach the pipeline design pressure and is even higher than the design pressure, a safety valve group 22 is arranged on the pipeline between the pneumatic emergency cut-off valve 3 and the manual stop valves 1 and 2, when the pressure in the pipeline is higher than the set value of the safety valve, the safety valve is opened, and a small amount of low-temperature liquid enters the diffusing and collecting pipe through the safety valve and is collected to a valve group pry connector G; because when the pneumatic emergency cut-off valve 5 and the manual stop valve 6 are closed simultaneously, LNG in a sealed pipe section is formed in the middle for natural gasification, and the pressure in the pipeline can reach the pipeline design pressure and is even higher than the design pressure, a safety valve group 23 is arranged on the pipeline between the pneumatic emergency cut-off valve 5 and the manual stop valve 6, when the pressure in the pipeline is higher than the set value of the safety valve, the safety valve is opened, and a small amount of low-temperature liquid enters the diffusing and collecting pipe through the safety valve and is collected to a valve group prying interface G; the manual stop valve 12 and the

safety valve banks

24 and 25 are arranged at the downstream of the valve bank pry interface E to ensure the safety of the LNG storage tank and prevent the safety valve from breaking down, so that two groups of safety valve banks are arranged, namely the safety valve bank 24 and the safety valve bank 25, the manual stop valve 12, the safety valve bank 24 and the safety valve bank 25 are in parallel connection, when the pressure in the storage tank is higher than a set value of the safety valve, the safety valve is opened, a large amount of low-temperature gas enters the diffusing and collecting pipe through the safety valve and is collected to the valve bank pry interface G, the manual stop valve 12 is manually opened when the pressure in the storage tank needs to be manually relieved, and under the normal condition, the manual stop valve 12 is normally closed, a large amount of low-temperature; the diffusing collecting pipe is connected to a valve bank pry interface G, and the interface G is connected to an EAG diffusing main pipe of the station; interface A is connected with the liquid outlet of LNG transport tank car, and interface B is connected with the liquid phase import of the storage tank booster outside the system, and G is connected with the total pipe of diffusing, and H is connected with the liquid outlet main pipe, and I is connected with the gaseous phase export of storage tank booster.

The invention has the following beneficial effects: 14 valves of storage tank interface and 4 groups of relief valves (safe diffusion + manual diffusion) are combined into a system, vacuum tubes are adopted in the system for heat preservation, and pipelines and valves are arranged in a layered mode, so that functional requirements are met, space is reduced, and operation is facilitated.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic of the present invention.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "upper", "lower", "horizontal", "inside", "outside", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Example 1

As shown in fig. 1, a low-temperature storage tank interface valve group system of an LNG gasification station comprises a liquid inlet main pipe part and a liquid outlet main pipe part, wherein the liquid inlet main pipe part comprises two branches, one branch is connected with a pressurized liquid inlet pipe of an LNG storage tank, a valve 4 is arranged on the liquid inlet main pipe of the storage tank pressurizer and connected to a port B, the other branch is provided with a starting emergency cut-off valve 3, a ZSOV and a VIC are arranged at the valve 3, the ZSOV is used for controlling a pneumatic emergency cut-off valve (a valve can be controlled to be opened and closed remotely in a control chamber), the VIC is used for feeding back a valve position of the pneumatic emergency cut-off valve (the valve can be observed in the control chamber to be opened and closed), a valve 1 and a valve 2 are arranged at the downstream of the valve 3 and respectively communicated with an upper liquid; the gas phase pipe is connected with a gas phase port of the storage tank through a connector E, the gas phase pipe is a bidirectional vent pipe, a gas inlet pipe in the gas inlet direction passes through a connector I connected with a supercharger of the storage tank, a valve 7 is arranged at the downstream of the connector I and then is connected to the connector E and is connected with the storage tank, a valve 8, a valve 9, a valve 10 and a valve 11 are arranged in the gas outlet direction in a combined mode, the valve 8 is a bypass passage formed by combining the valve 9, the valve 10 and the valve 11, namely the valve 8, the valve 9, the valve 10 and the valve 11 are combined in a parallel connection mode, the valve 11 is a pressure detection valve for detecting the pressure of gas in the gas phase pipe, if the pressure is higher than a set value, the valve 11 is automatically opened and is connected with a; the interface F connects the liquid outlet pipe with the liquid outlet of the storage tank, an emergency cut-off valve 5 is arranged at the downstream of the liquid outlet pipe, the valve 5 is a starting valve, ZOV and VIC are arranged at the position of the valve 5, a valve 6 is arranged at the downstream of the valve 5, the valve 6 is a manual valve and is then connected with an interface H, and the interface H leads to a liquid outlet main pipe; the safety valve group 21 is arranged at the upstream of the emergency cut-off valve 3 of the liquid inlet main pipe, the safety valve group 21 is opened when the pipeline pressure is higher than a set value, a small amount of low-temperature liquid enters a bleeding pipe, and the bleeding pipe is connected with a bleeding main pipe through a connector G; when the valves 3, 1 and 2 are closed simultaneously, closed pipelines are generated between the valves 3 and 1 and 2, and the pipelines have the possibility of exceeding the design pressure, so that a safety valve group 22 is arranged between the valves 3 and 1 and 2, when the pipeline pressure is higher than a set value, the safety valve group 22 is opened, a small amount of low-temperature liquid enters a bleeding pipe, and the bleeding pipe is connected with a bleeding main pipe through a connector G; when the valves 5 and 6 are closed simultaneously, a closed pipeline is generated between the valves 5 and 6, and the pipeline has the possibility of exceeding the design pressure, so that a safety valve group 23 is arranged between the valves 5 and 6, when the pipeline pressure is higher than a set value, the safety valve group 23 is opened, a small amount of low-temperature liquid enters a bleeding pipe, and the bleeding pipe is connected with a bleeding main pipe through a connector G; a plurality of safety valve sets in parallel connection are arranged at the downstream of the gas-phase pipe, preferably two

safety valve sets

24 and 25 are arranged, when the pressure of the gas-phase pipe is higher than a set value, the

safety valve sets

24 and 25 are simultaneously opened, redundant gas is discharged into the bleeding pipe and is connected with the bleeding main pipe through a connector G, and if one of the safety valve sets fails, the other safety valve set can still ensure normal work and system safety;

and (3) system diffusing flow: when the pressure in the pipeline is higher than the set value of the safety valve, the safety valve group 21 is opened, and a small amount of low-temperature liquid enters the diffusing and collecting pipe through the safety valve group 21 and is collected to a valve group prying port G; because LNG in the middle sealed pipe section is naturally gasified when the pneumatic emergency cut-off valve 3 and the manual stop valves 1 and 2 are closed simultaneously, the pressure in the pipeline can reach the pipeline design pressure and is even higher than the design pressure, a safety valve group 22 is arranged on the pipeline between the pneumatic emergency cut-off valve 3 and the manual stop valves 1 and 2, when the pressure in the pipeline is higher than the set value of the safety valve, the safety valve is opened, and a small amount of low-temperature liquid enters the diffusing and collecting pipe through the safety valve and is collected to a valve group pry connector G; because when the pneumatic emergency cut-off valve 5 and the manual stop valve 6 are closed simultaneously, LNG in a sealed pipe section is formed in the middle for natural gasification, and the pressure in the pipeline can reach the pipeline design pressure and is even higher than the design pressure, a safety valve group 23 is arranged on the pipeline between the pneumatic emergency cut-off valve 5 and the manual stop valve 6, when the pressure in the pipeline is higher than the set value of the safety valve, the safety valve is opened, and a small amount of low-temperature liquid enters the diffusing and collecting pipe through the safety valve and is collected to a valve group prying interface G; the manual stop valve 12 and the

safety valve banks

24 and 25 are arranged at the downstream of the valve bank pry interface E to ensure the safety of the LNG storage tank and prevent the safety valve from breaking down, so that two groups of safety valve banks are arranged, namely the safety valve bank 24 and the safety valve bank 25, the manual stop valve 12, the safety valve bank 24 and the safety valve bank 25 are in parallel connection, when the pressure in the storage tank is higher than a set value of the safety valve, the safety valve is opened, a large amount of low-temperature gas enters the diffusing and collecting pipe through the safety valve and is collected to the valve bank pry interface G, the manual stop valve 12 is manually opened when the pressure in the storage tank needs to be manually relieved (normally, the manual stop valve 12 is normally closed), a large amount of low-temperature gas enters the; the diffusing collecting pipe is connected to a valve bank pry interface G, and the interface G is connected to an EAG diffusing main pipe of the station; interface A is connected with the liquid outlet of LNG transport tank car, and interface B is connected with the liquid phase import of the storage tank booster outside the system, and G is connected with the total pipe of diffusing, and H is connected with the liquid outlet main pipe, and I is connected with the gaseous phase export of storage tank booster.

Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A low-temperature storage tank interface valve group system of an LNG (liquefied natural gas) gasification station is characterized by comprising a liquid inlet main pipe part and a liquid outlet main pipe part, wherein the liquid inlet main pipe part comprises two branches, one branch is connected with a pressurization liquid inlet pipe of an LNG storage tank, a valve (4) is arranged on the liquid inlet main pipe of the storage tank pressurization and connected to a connector (B), the other branch is provided with a starting emergency cut-off valve (3), the valve (3) is provided with ZSOV and VIC, a valve (1) and a valve (2) are arranged at the downstream of the valve (3) and respectively communicated with an upper liquid inlet main pipe and a lower liquid inlet main pipe of the storage tank and connected to a connector (C) and a connector (D), the connector (C) is connected with an upper; the gas phase pipe is connected with a gas phase port of the storage tank through a connector (E), the gas phase pipe is a bidirectional vent pipe, a gas inlet pipe in the gas inlet direction is connected with the storage tank supercharger through a connector (I) connected with the storage tank supercharger, a valve (7) is arranged at the downstream of the connector (I) and then connected with the connector (E) and connected with the storage tank, a valve (8), a valve (9), a valve (10) and a valve (11) are combined in the gas outlet direction, the valve (8) is a bypass passage formed by combining the valve (9), the valve (10) and the valve (11), namely the valve (8), the valve (9), the valve (10) and the valve (11) are combined and connected in parallel, the valve (11) is a pressure detection valve, and if the pressure is higher than a set value, the valve (11) is automatically opened and is connected with a BOG; the liquid outlet pipe is connected with a liquid outlet of the storage tank through the interface (F), an emergency cut-off valve (5) is arranged at the downstream of the liquid outlet pipe, the valve (5) is a starting valve, ZOV and VIC are arranged at the position of the valve (5), a valve (6) is arranged at the downstream of the valve (5), the valve (6) is a manual valve and is then connected with the interface (H), and the interface (H) leads to a liquid outlet main pipe; the safety valve group (21) is arranged at the upstream of the emergency cut-off valve (3) of the liquid inlet main pipe, when the pipeline pressure is higher than a set value, the safety valve group (21) is opened, a small amount of low-temperature liquid enters the diffusing pipe, and the diffusing pipe is connected with the diffusing main pipe through a connector (G); a safety valve group (22) is arranged between the valve (3) and the valves (1 and 2), when the pipeline pressure is higher than a set value, the safety valve group (22) is opened, a small amount of low-temperature liquid enters a diffusing pipe, and the diffusing pipe is connected with a diffusing main pipe through a connector (G); a safety valve group (23) is arranged between the valve (5) and the valve (6), when the pipeline pressure is higher than a set value, the safety valve group (23) is opened, a small amount of low-temperature liquid enters a diffusing pipe, and the diffusing pipe is connected with a diffusing main pipe through a connector (G); a plurality of safety valve banks which are connected in parallel are arranged at the downstream of the gas-phase pipe, when the pressure of the gas-phase pipe is higher than a set value, the plurality of safety valve banks are simultaneously opened, redundant gas is discharged into the bleeding pipe and is connected with the bleeding main pipe through a connector (G), and if one of the safety valve banks fails, the other safety valve banks can still ensure normal work and ensure the safety of the system.

2. A control method of an interface valve block system of a low-temperature storage tank of an LNG (liquefied natural gas) gasification station is characterized in that when the pressure in a pipeline is higher than a set value of a safety valve, a safety valve block (21) is opened, and a small amount of low-temperature liquid enters a diffusing and collecting pipe through the safety valve block (21) and is collected to a valve block prying interface (G); because when the pneumatic emergency cut-off valve (3) and the manual stop valves (1) and (2) are closed simultaneously, LNG in a closed pipe section is formed in the middle for natural gasification, and the pressure in a pipeline can reach the pipeline design pressure and is even higher than the design pressure, a safety valve group (22) is arranged on the pipeline between the pneumatic emergency cut-off valve (3) and the manual stop valves (1) and (2), when the pressure in the pipeline is higher than the set value of the safety valve, the safety valve is opened, and a small amount of low-temperature liquid enters the diffusing and collecting pipe through the safety valve and is collected to a valve group prying interface (G); because LNG in the sealed pipe section is naturally gasified in the middle when the pneumatic emergency cut-off valve (5) and the manual stop valve (6) are closed simultaneously, the pressure in the pipeline can reach the pipeline design pressure and is even higher than the design pressure, a safety valve group (23) is arranged on the pipeline between the pneumatic emergency cut-off valve (5) and the manual stop valve (6), when the pressure in the pipeline is higher than the set value of the safety valve, the safety valve is opened, and a small amount of low-temperature liquid enters the diffusing and collecting pipe through the safety valve and is collected to a valve group prying interface (G); the LNG storage tank is provided with a manual stop valve (12) and safety valve banks (24) and (25) at the downstream of a valve bank pry interface (E) for ensuring the safety of the LNG storage tank, and the safety valve is prevented from being broken down, so that two groups of safety valve banks are arranged, namely the safety valve bank (24) and the safety valve bank (25), the manual stop valve (12), the safety valve bank (24) and the safety valve bank (25) are in a parallel connection relation, when the pressure in the storage tank is higher than a safety valve set value, the safety valve is opened, a large amount of low-temperature gas enters a diffusing and collecting pipe through the safety valve and is collected to a valve bank pry interface (G), the manual stop valve (12) is manually opened when the pressure in the storage tank is required to be manually relieved, the manual stop valve (12) is normally closed, a large amount of; the diffusing collecting pipe is connected to a valve bank pry interface (G), and the interface (G) is connected to an EAG diffusing main pipe of the station; the interface (A) is connected with a liquid outlet of the LNG transport tank car, the interface (B) is connected with a liquid phase inlet of a storage tank supercharger outside the system, (G) is connected with a bleeding main pipe, (H) is connected with a liquid outlet main pipe, and (I) is connected with a gas phase outlet of the storage tank supercharger.