CN111237628A

CN111237628A - Low-temperature storage tank

Info

Publication number: CN111237628A
Application number: CN201811435858.5A
Authority: CN
Inventors: 顾华; 刘东进; 尹红伟; 李晓晨; 徐小艳
Original assignee: China International Marine Containers Group Co Ltd; Zhangjiagang CIMC Sanctum Cryogenic Equipment Co Ltd; CIMC Enric Investment Holdings Shenzhen Co Ltd
Current assignee: China International Marine Containers Group Co Ltd; Zhangjiagang CIMC Sanctum Cryogenic Equipment Co Ltd; CIMC Enric Investment Holdings Shenzhen Co Ltd
Priority date: 2018-11-28
Filing date: 2018-11-28
Publication date: 2020-06-05

Abstract

The invention relates to the technical field of low-temperature storage tanks, in particular to a low-temperature storage tank. The device comprises a tank body for containing cryogenic liquid and a liquid outlet device which is communicated with the tank body and is used for conveying the cryogenic liquid outwards; the liquid outlet device comprises a liquid outlet pipe and a valve; the liquid outlet pipe comprises a starting pipe section inserted into the liquid phase space of the tank body, a buffer pipe section for buffering low-temperature liquid and a tail end pipe section penetrating out of the tank body; two ends of the buffer pipe section are respectively connected with the starting pipe section and the tail end pipe section; the buffer pipe section is fixed in the tank body and at least partially positioned in the gas phase space of the tank body; the valve is arranged on the tail end pipe section and used for controlling the on-off of the liquid outlet pipe. The invention greatly increases the maintenance time of the low-temperature storage tank in the standing process; the frequent take-off of the safety valve is avoided, the BOG gas discharge amount is greatly reduced, the economic loss and the potential safety hazard are reduced, and the economy and the sociality are further ensured.

Description

Low-temperature storage tank

Technical Field

The invention relates to the technical field of low-temperature storage tanks, in particular to a low-temperature storage tank.

Background

At present, in the filling process of the vacuum heat insulation low-temperature storage tank, BOG gas in the tank body and the tank body can be cooled through a top spray pipe. In the use process of the vacuum heat insulation low-temperature storage tank, redundant BOG gas can be preferentially discharged out of the tank through the regulating valve and the saving pipeline, so that the pressure reduction of the vacuum heat insulation low-temperature storage tank is realized. However, in the use process of the vacuum heat insulation low-temperature storage tank, no cooling and cooling measures are taken, the influence of heat of the external environment on the vacuum heat insulation low-temperature storage tank cannot be reduced, and a large amount of BOG gas is continuously generated in the vacuum heat insulation low-temperature storage tank, so that the vacuum heat insulation low-temperature storage tank is inevitably pressurized faster, the safety valve is frequently jumped, the BOG gas is discharged out of the tank, economic loss is caused, potential safety hazards exist, and the economy and the sociality are influenced.

Disclosure of Invention

The invention aims to provide a low-temperature storage tank to solve the problem that the economic efficiency and the social efficiency are influenced because the pressure is quickly increased in the use process of a vacuum heat-insulation low-temperature storage tank in the prior art.

The purpose of the invention is realized by the following technical scheme:

the invention provides a low-temperature storage tank, which comprises a tank body for containing low-temperature liquid and a liquid outlet device communicated with the tank body and used for conveying the low-temperature liquid outwards; the liquid outlet device comprises a liquid outlet pipe and a valve; the liquid outlet pipe comprises a starting pipe section inserted into the liquid phase space of the tank body, a buffer pipe section for buffering low-temperature liquid and a tail end pipe section penetrating out of the tank body; the two ends of the cache pipe section are respectively connected with the starting pipe section and the tail end pipe section; the buffer pipe section is fixed in the tank body, and at least part of the buffer pipe section is positioned in the gas phase space of the tank body; the valve is arranged on the tail end pipe section and used for controlling the on-off of the liquid outlet pipe.

Preferably, the buffer pipe section is located entirely in the gas phase space.

Preferably, the buffer pipe section bypasses the gas phase space of the tank body.

Preferably, the buffer pipe section comprises a plurality of first pipe sections extending along a first direction and a plurality of second pipe sections extending along a second direction; an included angle is formed between the first direction and the second direction; the first pipe sections are arranged at intervals along a second direction; two ends of the second pipe section are respectively communicated with two adjacent first pipe sections.

Preferably, the first pipe section and the second pipe section are attached to the inner wall of the tank body.

Preferably, a plurality of the second tube segments are staggered along the second direction.

Preferably, the low-temperature storage tank is a horizontal low-temperature storage tank; the first direction is the width direction of the tank body; the second direction is the length direction of the tank body.

Preferably, the low-temperature storage tank is a horizontal low-temperature storage tank; the buffer pipe section is in a spiral shape; the integral extending direction of the buffer pipe section is parallel to the length direction of the tank body, and the upper part of the buffer pipe section is positioned in the gas phase space of the tank body.

Preferably, the buffer pipe section is attached to the inner wall of the tank body.

Preferably, the buffer pipe section is a stainless steel pipe or a finned pipe.

According to the technical scheme, the invention has the advantages and positive effects that: the liquid outlet pipe comprises a starting pipe section, a buffer pipe section and a tail end pipe section; inserting the initial pipe section into the liquid phase space of the tank body; the buffer pipe section is used for buffering low-temperature liquid and is positioned in the gas phase space of the tank body; the end pipe section penetrates out of the tank body from inside to outside. When the valve is opened, because the external air pressure is smaller than the air pressure in the tank body, the low-temperature liquid in the tank body can be filled into the buffer pipe section under the natural pressure difference, and then the low-temperature liquid in the buffer pipe section can absorb the heat of the gas phase space of the tank body, the later vaporization difficulty is reduced, and the temperature of the gas phase space in the tank body is reduced; when the valve is closed, the low-temperature liquid is stored in the buffer pipe section, so that the low-temperature liquid in the buffer pipe section can continuously absorb the heat of the gas phase space of the tank body, and the volume of the low-temperature gas vaporized from the low-temperature liquid in the buffer pipe section is reduced or liquefied after heat exchange with the low-temperature liquid in the tank body, so that the pressure increasing speed of the low-temperature storage tank is slowed down; after receiving heat transferred from the external environment, the low-temperature liquid in the tank body evaporates to form low-temperature gas, so that the temperature of a gas phase space in the tank body is increased, and the low-temperature liquid in the buffer pipe section is vaporized into the low-temperature gas; therefore, the low-temperature gas and the low-temperature liquid are circularly converted, the generation speed of the BOG gas is greatly reduced, the pressure rising speed of the low-temperature storage tank is reduced, and the maintaining time of the low-temperature storage tank in the standing process is greatly prolonged; the frequent take-off of the safety valve is avoided, the BOG gas discharge amount is greatly reduced, the economic loss and the potential safety hazard are reduced, and the economy and the sociality are further ensured.

Drawings

For the purpose of easy explanation, the present invention will be described in detail with reference to the following preferred embodiments and the accompanying drawings.

Fig. 1 is a schematic structural view of a preferred embodiment of the cryogenic tank of the present invention.

Description of reference numerals: 1. a tank body; 11. an inner container; 12. a housing; 13. a longitudinal central axis plane; 2. a liquid outlet device; 21. a liquid outlet pipe; 211. a starting pipe section; 212. caching a pipe section; 2121. a first tube section; 2122. a second tube section; 213. the end pipe section.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", may explicitly or implicitly include one or more of the described features. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the description of the present invention, it should be noted that the terms "mounted," "connected," and "connected" are to be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally connected unless otherwise explicitly stated or limited. Either mechanically or electrically. Either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

The invention provides a low-temperature storage tank, which comprises a tank body 1 for containing low-temperature liquid and a liquid outlet device 2 communicated with the tank body 1 and used for conveying the low-temperature liquid outwards, wherein the liquid outlet device 2 can slow down the pressure rise speed of the low-temperature storage tank in the use process, so that the maintenance time is greatly prolonged; and the frequent take-off of the safety valve is avoided, the BOG gas discharge amount is reduced, the economic loss and the potential safety hazard are reduced, and the economy and the sociality are further ensured. The low-temperature storage tank can be a horizontal low-temperature storage tank or a vertical low-temperature storage tank.

Referring to fig. 1, the horizontal cryogenic tank is taken as an example for a detailed description in the present embodiment.

The tank body 1 is used for containing cryogenic liquid. In this embodiment, the tank 1 is a double-layer shell, and includes an inner container 11 and an outer shell 12 sleeved outside the inner container 11. The interlayer space between the outer shell 12 and the inner container 11 can be filled with a thermal insulation material and forms a vacuum environment to insulate the inner container 11. The inner container 11 comprises a first cylinder and two first end sockets connected to both ends of the first cylinder. The housing 12 includes a second cylinder and two second headers connected to both ends of the second cylinder. The second cylinder is positioned at the outer side of the first cylinder; the two first seal heads are both positioned between the two second seal heads.

The liquid outlet device 2 comprises a liquid outlet pipe 21 and a valve (not shown). Effluent pipe 21 includes, among other things, a start pipe section 211, a buffer pipe section 212, and an end pipe section 213. The initial pipe section 211 and the buffer pipe section 212 are fixed in the inner vessel 11, and the end pipe section 213 penetrates out of the outer shell 12, so that the cryogenic liquid in the tank 1 is conveyed outwards through the liquid outlet device 2. A valve is disposed on end segment 213 and outside of housing 12 to control the opening and closing of outlet pipe 21.

The initial pipe section 211 extends from bottom to top and is attached to the arc inner wall of the tank body 1. The lower end of the starting pipe section 211 is inserted into the liquid phase space of the tank 1. Wherein, the liquid phase space refers to the space where the cryogenic liquid is located, and the gas phase space refers to the space where the cryogenic gas is located.

The end pipe section 213 passes from the interior of the inner vessel 11 to the exterior of the outer vessel 12, and the outer end of the end pipe section 213 is located at the bottom of the outer vessel. Therefore, the external connection pipeline can be conveniently connected with the outer end of the tail end pipe section 213, the external connection pipeline is convenient to arrange, and the space is saved.

The buffer pipe section 212 adopts stainless steel pipelines or finned pipes to sufficiently reduce the temperature of the tank body 1. Of course, the starting pipe segment 211 and the end pipe segment 213 may also adopt the same pipe structure as the buffer pipe segment 212.

The buffer pipe section 212 is used for buffering cryogenic liquid. The buffer pipe section 212 has two ends respectively communicated with the upper end of the initial pipe section 211 and the inner end of the terminal pipe section 213. It should be noted that in the present embodiment, the buffer pipe section 212 is entirely located in the gas phase space and bypasses the gas phase space of the tank 1, so that the cryogenic liquid in the buffer pipe section 212 can absorb heat from the gas phase space of the tank 1. Moreover, the buffer pipe section 212 is attached to the top of the inner wall of the tank body 1, so that in the liquid outlet process, the low-temperature liquid in the buffer pipe section 212 can absorb the heat of the inner wall of the top of the inner wall of the tank body 1, the temperature of the top of the inner wall of the tank body 1 is reduced to be close to the temperature of the liquid phase space of the tank body 1, and further the tank body 1 can absorb more external heat, so as to prolong the maintenance time of the low-temperature storage tank.

The buffer tube section 212 is wavy. The cache pipe segment 212 includes a plurality of first pipe segments 2121 and a plurality of second pipe segments 2122.

The plurality of first pipe sections 2121 are uniformly arranged at intervals along the length direction of the tank body 1, and the plurality of first pipe sections 2121 are parallel. Each first pipe section 2121 extends along the width direction of the tank body 1 and is attached to the inner wall of the tank body 1. The ends of each first tube 2121 are located on the two sides of the longitudinal central axial plane 13 of the tank 1. Wherein the longitudinal mid-axis plane 13 is a vertical plane passing through the longitudinal axis of the can body 1. The first and the last pipe sections 2121 are respectively communicated with the starting pipe section 211 and the end pipe section 213, the first pipe section 2121 and the starting pipe section 211 at the head end are close to the first end of the tank body 1, and the first pipe section 2121 and the end pipe section 213 at the tail end are close to the second end of the tank body 1.

The second pipe section 2122 extends in the longitudinal direction of the can body 1, and the plurality of second pipe sections 2122 are parallel. The second pipe sections 2122 are arranged in a staggered manner along the length of the tank 1. The second tube section 2122 fits against the inner wall of the tank 1. Two ends of each second pipe section 2122 are respectively communicated with two adjacent first pipe sections 2121. Three adjacent first tube sections 2121 and two second tube sections 2122 connecting the three adjacent first tube sections 2121 form an S-shaped structure.

The working principle of the embodiment is as follows: the initial pipe section 211 is inserted into the liquid phase space of the tank 1; the buffer pipe section 212 is used for buffering low-temperature liquid and is positioned in the gas phase space of the tank body 1; the end pipe section 213 passes out of the tank 1 from the inside to the outside. When the valve is opened, since the external air pressure is smaller than the air pressure in the tank body 1, the low-temperature liquid in the tank body 1 can be filled into the buffer pipe section 212 under the natural pressure difference. In the process that cryogenic liquid outwards flows out, cryogenic liquid in the buffer pipe section 212 can absorb the heat in the gas phase space of the tank body 1, so that the temperature in the gas phase space of the tank body 1 is reduced to be close to the temperature in the liquid phase space of the tank body 1, meanwhile, the temperature of the flowing cryogenic liquid is improved, and further the later stage vaporization difficulty is reduced.

When the valve is closed, the low-temperature liquid is cached in the cache pipe section 212, so that the low-temperature liquid in the cache pipe section 212 can continuously absorb the heat of the gas phase space of the tank body 1, the temperature of the tank body 1 is increased due to continuous absorption of heat radiation and heat conduction, and the low-temperature liquid in the cache pipe section 212 is vaporized into low-temperature gas. The cryogenic gas enters the liquid phase space of the tank body 1 through the initial pipe section 211, and then the cryogenic gas is subjected to heat transfer, heat radiation and heat convection with the cryogenic liquid in the tank body 1, so that the temperature is further reduced, the volume is reduced, and even the cryogenic gas is liquefied, and the pressure increase speed of the cryogenic storage tank is reduced. The low-temperature liquid in the tank body 1 can receive the heat transferred by the low-temperature gas in the buffer pipe section 212; after receiving heat transferred from the external environment, the cryogenic liquid in the tank body 1 evaporates to produce cryogenic gas, which increases the temperature of the gas phase space in the tank body 1 and also causes the cryogenic liquid in the buffer pipe section 212 to vaporize into cryogenic gas. Therefore, the low-temperature gas and the low-temperature liquid are circularly converted, the generation speed of the BOG gas is greatly reduced, the pressure rising speed of the low-temperature storage tank is reduced, and the maintaining time of the low-temperature storage tank in the standing process is greatly prolonged; and the frequent jump of the safety valve is avoided, the BOG gas discharge amount is greatly reduced, the economic loss and the potential safety hazard are reduced, and the economy and the sociality are further ensured. It should be mentioned that the low-temperature liquid in this embodiment is a supercooled liquid, and the supercooled liquid is not in a saturated state, so that the low-temperature gas is not directly evaporated under the heat of the low-temperature gas in the buffer pipe section.

In other embodiments, not shown, the buffer pipe section may be spaced apart from the inner wall of the tank body, and the buffer pipe section may be fixed in the tank body, for example, the first pipe section and the second pipe section are both straight pipes, the plurality of first pipe sections are parallel and located in the same plane, and the plurality of second pipe sections are parallel, at this time, the cryogenic liquid in the buffer pipe section can absorb the heat in the gas phase space of the tank body.

In other embodiments, not shown, the first tube segments extend in a first direction and the plurality of first tube segments are evenly spaced in a second direction. The second tube segments extend along a second direction, and the plurality of second tube segments are arranged in a staggered manner along the second direction. The first direction is oblique to the second direction. Of course, the first direction may also be the length direction of the can body, while the second direction is the width direction of the can body.

In other embodiments not shown in the drawings, the buffer pipe section may also be a coiled pipe, and in this case, the buffer pipe section is integrally coiled in the gas phase space of the tank body, and the buffer pipe section is in a shape of a Chinese character 'hui'.

In other embodiments not shown, a vertical cryogenic tank may be used as the cryogenic tank. At the moment, the first pipe section and the second pipe section are fixed and attached to the first sealing head on the top of the tank body, and the tail end pipe section penetrates out of the top of the tank body. Of course, the buffer pipe section in this embodiment may also be a coil pipe, and the buffer pipe section is in a shape of a Chinese character 'hui', and the buffer pipe section is integrally attached to the first end seal at the top of the tank body.

In other embodiments, not shown, the cryogenic tank is a horizontal cryogenic tank, in which case the buffer pipe section may be helical, and the overall extension direction of the buffer pipe section is the same as the length direction of the tank body. The top of the buffer pipe section is located in the gas phase space of the tank body, and the rest of the buffer pipe section is submerged in the liquid phase space of the tank body.

The working principle of the embodiment is as follows: inserting the initial pipe section into the liquid phase space of the tank body; the buffer pipe section is used for buffering low-temperature liquid and is positioned in the gas phase space of the tank body; the end pipe section penetrates out of the tank body from inside to outside. When the valve is opened, the low-temperature liquid in the tank body can be filled into the buffer pipe section under the natural pressure difference because the external air pressure is less than the air pressure in the tank body. In the process that cryogenic liquid outwards flows, cryogenic liquid in the buffer memory pipeline section can absorb the heat in the gas phase space of the jar body for the temperature in the gas phase space of the jar body reduces to the temperature in the liquid phase space that is close to the jar body, simultaneously, has improved the temperature of the cryogenic liquid that flows, and then has reduced the later stage degree of difficulty that vaporizes.

When the valve is closed, the low-temperature liquid is cached in the cache pipe section, so that the low-temperature liquid in the cache pipe section can continuously absorb the heat of the gas phase space of the tank body, the temperature of the tank body is increased due to continuous absorption of thermal radiation and thermal conduction, and the low-temperature liquid in the cache pipe section is vaporized into low-temperature gas. After the low-temperature gas enters the liquid phase space of the buffer pipe section, heat transfer, heat radiation and heat convection are carried out on the low-temperature gas through the buffer pipe section and the low-temperature liquid in the tank body, so that the temperature is further reduced, the volume is reduced, and even the low-temperature gas is liquefied, and the pressure and the speed of the low-temperature storage tank are reduced. The low-temperature liquid in the tank body can receive heat transferred by the low-temperature gas in the buffer pipe section; after receiving external heat, the low-temperature liquid in the tank body evaporates to form low-temperature gas, so that the temperature of a gas phase space in the tank body is increased, and the low-temperature liquid in the buffer pipe section is vaporized into the low-temperature gas. Therefore, the low-temperature gas and the low-temperature liquid are circularly converted, the generation speed of the BOG gas is greatly reduced, the pressure rising speed of the low-temperature storage tank is reduced, and the maintaining time of the low-temperature storage tank in the standing process is greatly prolonged; and the frequent jump of the safety valve is avoided, the BOG gas discharge amount is greatly reduced, the economic loss and the potential safety hazard are reduced, and the economy and the sociality are further ensured.

The invention has at least the following advantages:

1. in the liquid outlet process, the low-temperature liquid in the buffer pipe section 212 can bring heat in the gas phase space of the tank body 1, and meanwhile, the temperature of the flowing low-temperature liquid is improved, so that the later stage vaporization difficulty is reduced. When liquid discharge is stopped, heat exchange is carried out between the low-temperature gas generated in the buffer pipe section 212 and the low-temperature liquid in the tank body 1, and the pressure increasing speed of the low-temperature storage tank is slowed down; the low-temperature liquid in the tank body 1 is evaporated into low-temperature gas by the external heat. Therefore, the low-temperature gas and the low-temperature liquid are circularly converted, the generation speed of BOG gas is greatly reduced, the pressure rising speed of the low-temperature storage tank is reduced, and the maintaining time of the low-temperature storage tank in the standing process is greatly prolonged. The frequent take-off of the safety valve is avoided, the BOG gas discharge amount is greatly reduced, the economic loss and the potential safety hazard are reduced, and the economy and the sociality are further ensured.

2. The buffer pipe section 212 is attached to the top of the inner wall of the tank body 1, in the liquid outlet process, the low-temperature liquid in the buffer pipe section 212 can absorb the heat of the top of the inner wall of the tank body 1, the temperature of the top of the inner wall of the tank body 1 is reduced to be close to the temperature of the liquid phase space of the tank body 1, and then the tank body 1 can absorb more external heat, so that the holding time of the low-temperature storage tank is prolonged.

In the description of the present specification, reference to the description of the terms "one embodiment", "some embodiments", "an illustrative embodiment", "an example", "a specific example", or "some examples", etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims

1. A low-temperature storage tank comprises a tank body for containing low-temperature liquid and a liquid outlet device communicated with the tank body and used for conveying the low-temperature liquid outwards; it is characterized in that the liquid outlet device comprises:

the liquid outlet pipe comprises a starting pipe section inserted into the liquid phase space of the tank body, a buffer pipe section used for buffering low-temperature liquid and a tail end pipe section penetrating out of the tank body; the two ends of the cache pipe section are respectively connected with the starting pipe section and the tail end pipe section; the buffer pipe section is fixed in the tank body, and at least part of the buffer pipe section is positioned in the gas phase space of the tank body;

and the valve is arranged on the tail end pipe section and used for controlling the on-off of the liquid outlet pipe.

2. The cryogenic tank of claim 1, wherein the buffer tube section is located entirely in the vapor space.

3. The cryogenic tank of claim 2, wherein the buffer tube section is routed in a gas phase space of the tank.

4. The cryogenic storage tank of claim 3, wherein the buffer tube segments comprise a plurality of first tube segments extending in a first direction, and a plurality of second tube segments extending in a second direction;

an included angle is formed between the first direction and the second direction; the first pipe sections are arranged at intervals along a second direction; two ends of the second pipe section are respectively communicated with two adjacent first pipe sections.

5. The cryogenic storage tank of claim 4 wherein the first pipe section and the second pipe section both conform to an inner wall of the tank body.

6. The cryogenic tank of claim 4, wherein a plurality of the second pipe sections are staggered along the second direction.

7. The cryogenic storage tank of any one of claims 4 to 6 wherein the cryogenic storage tank is a horizontal cryogenic storage tank; the first direction is the width direction of the tank body; the second direction is the length direction of the tank body.

8. The cryogenic storage tank of claim 1, wherein the cryogenic storage tank is a horizontal cryogenic storage tank;

the buffer pipe section is in a spiral shape; the integral extending direction of the buffer pipe section is parallel to the length direction of the tank body, and the upper part of the buffer pipe section is positioned in the gas phase space of the tank body.

9. The cryogenic storage tank of claim 8 wherein the buffer tube segments are attached to an inner wall of the tank.

10. The cryogenic tank of claim 1, wherein the buffer tube section is a stainless steel tube or a finned tube.