CN212672948U

CN212672948U - Gasification structure of LNG storage and transportation station

Info

Publication number: CN212672948U
Application number: CN202021157292.7U
Authority: CN
Inventors: 李文忠; 佟跃胜; 安小霞; 杨帆; 于蓓蕾; 赵甲递
Original assignee: China Huanqiu Contracting and Engineering Corp
Current assignee: China Huanqiu Contracting and Engineering Corp
Priority date: 2020-06-19
Filing date: 2020-06-19
Publication date: 2021-03-09
Anticipated expiration: 2030-06-19

Abstract

The utility model provides a gasification structure of LNG warehousing and transportation station has empty warm formula vaporizer and SCV (submerged combustion formula vaporizer) of establishing ties, connects in parallel with first bypass and empty warm formula vaporizer between the front and back end of empty warm formula vaporizer, connects in parallel with second bypass and SCV between the front and back end of SCV, empty warm formula vaporizer and first bypass alternative intercommunication, SCV with bypass alternative intercommunication, empty warm formula vaporizer and SCV's at least one of them participate in gasification work, and the valve on first bypass and the second bypass sets up the interlocking, must not open simultaneously, and SCV's design needs can heat up to more than 0 ℃ according to the operating mode that can tolerate-162 ℃ LNG (liquefied natural gas), also can guarantee to heat up after-162 ℃ to 0 ℃ arbitrary temperature's between the natural gas gets into SCV.

Description

Gasification structure of LNG storage and transportation station

Technical Field

The utility model relates to a gasification structure that air temperature formula vaporizer and SCV combined together.

Background

LNG storage and transportation stations are generally provided with vaporizers, such as an Open Rack Vaporizer (ORV), a Submerged Combustion Vaporizer (SCV), and an intermediate medium heat exchange vaporizer (IFV), for vaporizing LNG. For small stations, there is also a gasification system using a combination of an air-temperature gasifier and a water-bath gasifier.

Among these, ORVs and IFVs typically require the use of large amounts of water, and some stations do not have the requirement of large water supplies, and only water bath heat exchangers or SCVs are used. The SCV is expensive in manufacturing cost and high in operation cost, so that the selection of the SCV by a plurality of stations is forbidden.

Therefore, the air-temperature gasifier is usually used to gasify LNG, and the working efficiency of the air-temperature gasifier is greatly affected by the ambient temperature, and when the ambient temperature for gas use is low in winter (for example, when the ambient temperature is lower than 10 ℃), the gasified gas temperature cannot reach the standard, so that the condition of external transportation cannot be met. Therefore, a structure combining an air-temperature gasifier and a water-bath gasifier is often selected, wherein the water-bath gasifier further heats up the low-temperature medium which does not reach the standard by using hot water to meet the output requirement, the hot water required by the water-bath gasifier is required to be provided by a boiler, and the boiler also needs to consume natural gas; the water bath type heat exchanger is poor in heat exchange effect and low in gasification capacity, the risk that accidents are caused due to the fact that heat exchange pipes are broken exists, pipelines need to be laid from a boiler to the water bath type gasifier, the pipelines need to be insulated, heat can still be leaked into the environment, and therefore the heat efficiency is further reduced. Furthermore, the flexibility and gasification capacity of water bath gasifiers is low compared to SCV.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a LNG storage and transportation station's gasification structure combines together empty temperature formula vaporizer and SCV, overcomes the not enough of the various prior art existence of above-mentioned.

In order to achieve the above object, the utility model adopts the following technical scheme:

the utility model provides a gasification structure of LNG warehousing and transportation station which characterized in that: the system comprises an air-temperature type gasifier and an SCV which are connected in series, wherein the air-temperature type gasifier and the SCV are connected in parallel by a first bypass between the front end and the rear end of the air-temperature type gasifier, the SCV is connected in parallel by a second bypass between the front end and the rear end of the SCV, the air-temperature type gasifier is communicated with one of the first bypass, the SCV is communicated with one of the bypasses, the air-temperature type gasifier and at least one of the SCV participate in gasification work, valves on the first bypass and the second bypass are interlocked and cannot be opened at the same time, the SCV can endure the working condition of LNG at the temperature of 162 ℃ below zero, and can also guarantee that the temperature of natural gas at any temperature of 162 ℃ below zero to 0 ℃ can be increased to above 0 ℃ after entering the SCV.

Wherein: the air temperature type gasifiers and the SCV are connected in series or in parallel.

Wherein: the air-temperature type gasifier is provided with a plurality of groups of air-temperature type gasifiers, and the air-temperature type gasifiers can be switched to use.

The utility model discloses an adopt the structure that air temperature formula vaporizer and SCV combined together, both reducible operation energy consumption can improve the heat utilization efficiency again, the gasified reliability of multiplicable field station simultaneously, and in case the heat exchange tube breaks, combustible medium in the heat exchange tube probably leads to the explosion to the shell destruction in case the heat exchange tube breaks because of the welded structure of its heat exchange tube is comparatively complicated and probably is corroded the heat exchange tube that arouses most importantly to have avoided water bath formula vaporizer to break in aqueous.

Drawings

Fig. 1 is a schematic diagram of a gasification structure of an LNG storage and transportation station provided by the present invention.

Description of reference numerals: air-temperature type gasifiers A (a plurality of gasifiers are in one group), air-temperature type gasifiers B (the number of gasifiers is the same as that of the gasifiers in the group A, the gasifiers in the other group); a first bypass 1; a submerged combustion gasifier (SCV) 2; a second bypass 3.

Detailed Description

The utility model provides a gasification structure of LNG warehousing and transportation station, empty warm formula vaporizer A, B and submerged combustion formula vaporizer (SCV)2 that have the series connection, can a plurality of empty warm formula vaporizers A, B connect in series and connect in parallel as a group), and can set up multiunit empty warm formula vaporizer A, B in order to form mainly using, reserve and can switch over the use, connect in parallel with first bypass 1 between the front and back end of empty warm formula vaporizer A, B, connect in parallel with second bypass 3 between the front and back end of submerged combustion formula vaporizer (SCV)2, empty warm formula vaporizer A, B and first bypass 1 can the alternative intercommunication, submerged combustion formula vaporizer (SCV)2 with the bypass can the alternative intercommunication, empty warm formula vaporizer A, B participates in gasification work with at least one of submerged combustion formula vaporizer (SCV)2, the valve setting on first bypass and the second bypass interlocks, must not open simultaneously, the SCV is designed to be able to withstand the working condition of LNG (liquefied natural gas, the same applies below) at the temperature of-162 ℃, and also to ensure that the temperature of the natural gas at any temperature between-162 ℃ and 0 ℃ can be raised to 0 ℃ after the natural gas enters the SCV.

The SCV needs to be designed according to different feeding working conditions: aiming at LNG feeding at-162 ℃, the minimum output load required by a station needs to be met so as to ensure the reliability of station output; aiming at the feeding of low-temperature natural gas at minus 10 ℃, the station needs to calculate the output mode of the maximum output quantity and the stability of the minimum output quantity under the working condition. The various operating conditions described above need to be considered for the design of an SCV.

Because the SCV heats the low-temperature medium and needs to heat the water in the SCV water tank, the water is contacted with the LNG (or the low-temperature gas), and the flue gas generated after the fuel gas is combusted is utilized to improve the heat exchange rate between the water in the water tank and the medium in the heat exchange tube, thereby reducing the heat loss. The fuel gas can be supplied to the combustion furnace of the SCV after the pressure reduction of the downstream pipeline gas, the fuel gas needs to be heated when the temperature of the gas is reduced after the pressure reduction, and the gas after the pressure reduction can enter a water pool of the SCV for heating and then enter the combustion furnace of the SCV, and the arrangement mode can reduce the heaters of the fuel gas.

The utility model discloses during the use, different working methods are adopted to the optional condition:

(1) when the environment is high, the output temperature can be reached after the gasification of the air temperature type gasifier A, B, the first bypass 1 is closed, the second bypass 3 is connected, the submerged combustion type gasifier (SCV)2 does not participate in the gasification work, the air temperature type gasifiers of the group A and the air temperature type gasifiers of the group B are switched with each other, one group works, the other group defrosts, and the group A and the group B are not used for the gasification of LNG at the same time under the normal working condition.

(2) When the ambient temperature is low, the outlet temperature of the air-temperature gasifier A, B cannot reach the output requirement, the first bypass 1 is closed, the second bypass 3 is also closed, the submerged combustion gasifier (SCV)2 is connected, and the gas enters the submerged combustion gasifier (SCV)2 to be further heated so as to reach the output requirement. When the submerged combustion gasifier (SCV)2 is selected, the heat exchange calculation needs to account for the heat exchange effect under the working condition.

(3) When the air-temperature type gasifier A, B has a fault or cannot be used due to certain factors (such as fog is too large), the first bypass 1 is connected, the second bypass 3 is closed, the air-temperature type gasifier A, B does not participate in the gasification work, and the LNG directly enters the submerged combustion type gasifier (SCV)2 to be gasified, so that the LNG gasification under the day-average output working condition needs to be considered while the model selection of the submerged combustion type gasifier (SCV) 2.

Compared with the prior art, the utility model discloses following beneficial effect has:

(1) the utility model discloses can make gasification time shorten: because the air-temperature type gasifier A, B and the submerged combustion type gasifier (SCV)2 are adopted, the starting is very fast, and the running reliability is high.

(2) The utility model discloses the energy consumption is very low: compared with the gasification by using a submerged combustion gasifier (SCV)2 all year round, the effect of saving the operation cost is very obvious; roughly calculated, for a station with the gasification capacity of 100 ten thousand tons/year, the operation cost of only 3 months in summer can be saved by 2400 ten thousand yuan.

(3) The utility model discloses compare empty temperature and add the gasification mode of water bath, need not use the boiler to produce hot water, the water bath formula vaporizer is carried again to hot water, and the thermal efficiency will improve greatly, reduces the heat loss among the hot water transmission process, has avoided the not high condition of gasification ability that the water bath formula vaporizer is relatively poor and lead to because of the heat transfer effect that only depends on the natural flow production of water simultaneously, its coil pipe of structure decision of water bath formula vaporizer is weak link, easily produces cracked danger, and the utility model discloses there is not this danger.

(4) The SCV needs to be designed according to different feeding working conditions: aiming at LNG feeding at-162 ℃, the minimum output load required by a station needs to be met so as to ensure the reliability of station output; aiming at the feeding of low-temperature natural gas at minus 10 ℃, the station needs to calculate the output mode of the maximum output quantity and the stability of the minimum output quantity under the working condition. The various operating conditions described above need to be considered for the design of an SCV. Because the SCV heats the low-temperature medium and needs to heat the water in the SCV water tank, the water is contacted with the LNG (or the low-temperature gas), and the flue gas generated after the fuel gas is combusted is utilized to improve the heat exchange rate between the water in the water tank and the medium in the heat exchange tube, thereby reducing the heat loss. The fuel gas can be supplied to the combustion furnace of the SCV after the pressure of the downstream pipeline gas is reduced, the fuel gas needs to be heated when the temperature of the gas is reduced after the pressure of the gas is reduced, and the gas after the pressure reduction can enter a water pool of the SCV for heating and then enter the combustion furnace of the SCV.

The foregoing description is intended to be illustrative rather than limiting, and it will be appreciated by those skilled in the art that many modifications, variations or equivalents may be made without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. The utility model provides a gasification structure of LNG warehousing and transportation station which characterized in that: the system comprises an air-temperature type gasifier and an SCV which are connected in series, wherein the air-temperature type gasifier and the SCV are connected in parallel by a first bypass between the front end and the rear end of the air-temperature type gasifier, the SCV is connected in parallel by a second bypass between the front end and the rear end of the SCV, the air-temperature type gasifier is communicated with one of the first bypass, the SCV is communicated with one of the bypasses, the air-temperature type gasifier and at least one of the SCV participate in gasification work, valves on the first bypass and the second bypass are interlocked and cannot be opened at the same time, the SCV can endure the working condition of LNG at the temperature of 162 ℃ below zero, and can also guarantee that the temperature of natural gas at any temperature of 162 ℃ below zero to 0 ℃ can be increased to above 0 ℃ after entering the SCV.

2. A vaporizing structure of an LNG storage and transportation station according to claim 1, wherein: the air temperature type gasifiers and the SCV are connected in series or in parallel.

3. A vaporizing structure of an LNG storage and transportation station according to claim 2, wherein: the air-temperature type gasifier is provided with a plurality of groups of air-temperature type gasifiers, and the air-temperature type gasifiers can be switched to use.