A method and system for recovering and processing bogs of lng receiving terminals

Abstract

The invention relates to a BOG (boil off gas) recovery processing method and system for an LNG (liquid natural gas) receiving terminal, and the BOG recovery processing method comprises the following steps: 1) setting a BOG recovery processing system under the working condition of no output operation of the LNG receiving terminal; 2) feeding BOG produced in an LNG full containment storage tank to the lower end of a BOG re-condenser after BOG is pressurized by a BOG compressor; 3) conveying overcooled LNG from the LNG full containment storage tank to the upper end of the BOG re-condenser by virtue of a pump in the LNG tank, and coming into contact with the BOG at the lower end of the BOG re-condenser to perform heat transfer so as to condense the BOG into LNG; 4) feeding LNG from the BOG re-condenser into an LNG main-sub tank, and then feeding the LNG from the LNG main-sub tank into an output loading system; and 5) feeding the BOG produced in the BOG re-condenser, the LNG main-sub tank and the output loading system into the BOG compressor for pressurizing together with the BOG in the LNG full containment storage tank through throttle control, feeding the pressurized BOG to the lower end of the BOG re-condenser, and going back to the step 3). The invention provides a BOG recovery processing method and system, which are capable of ensuring effective recovery utilization of BOG and can be widely applied to recovery utilization of BOG in the LNG receiving terminal.

Description

technical field

[0001] The invention relates to a method and system for comprehensive processing of BOG at an LNG (liquefied natural gas) receiving terminal, in particular to a method and system for recovering and processing BOG at an LNG receiving terminal under the operating condition of no external transportation. Background technique

[0002] In recent years, global LNG production and trade have become increasingly active. As a clean and efficient strategic energy source, LNG is becoming a new hotspot in the world's oil and gas industry. At present, my country is vigorously building LNG receiving terminals along the coast, which is conducive to stabilizing energy supply, ensuring energy security, diversifying the supply structure, and protecting the environment.

[0003] The daily evaporation rate of LNG in cryogenic storage tanks and cryogenic tankers is about 0.3%. This part of evaporated gas (lower temperature) is referred to as BOG (flash steam, Boil Off Gas). The LN...

Examples

Embodiment Construction

[0021] The present invention will be described in detail below in conjunction with the accompanying drawings and embodiments.

[0022] The present invention provides a method for recovering and processing BOG of an LNG receiving terminal under the operating condition of no external transmission, comprising the following steps:

[0023] 1) if figure 1 As shown, the BOG recovery and processing system of the LNG receiving terminal is set up, including the LNG full-capacity storage tank 1, the pump in the LNG tank 2, the BOG recondenser 3, the LNG sub-tank 4, the BOG compressor 5, the external transportation loading system 6, the second A regulating valve 7 , a second regulating valve 8 , a third regulating valve 9 and a fourth regulating valve 10 .

[0024] 2) The BOG produced in the LNG full-capacity storage tank 1 first enters the BOG compressor 5, and the BOG compressor 5 pressurizes the incoming BOG to increase the pressure of the BOG to 0.5MPaG-0.8MPaG, and then enters the ...

technical field

[0001] The invention relates to a method and system for comprehensive processing of BOG at an LNG (liquefied natural gas) receiving terminal, in particular to a method and system for recovering and processing BOG at an LNG receiving terminal under the operating condition of no external transportation. Background technique

[0002] In recent years, global LNG production and trade have become increasingly active. As a clean and efficient strategic energy source, LNG is becoming a new hotspot in the world's oil and gas industry. At present, my country is vigorously building LNG receiving terminals along the coast, which is conducive to stabilizing energy supply, ensuring energy security, diversifying the supply structure, and protecting the environment.

[0003] The daily evaporation rate of LNG in cryogenic storage tanks and cryogenic tankers is about 0.3%. This part of evaporated gas (lower temperature) is referred to as BOG (flash steam, Boil Off Gas). The LN...

Examples

Embodiment Construction

[0021] The present invention will be described in detail below in conjunction with the accompanying drawings and embodiments.

[0022] The present invention provides a method for recovering and processing BOG of an LNG receiving terminal under the operating condition of no external transmission, comprising the following steps:

[0023] 1) if figure 1 As shown, the BOG recovery and processing system of the LNG receiving terminal is set up, including the LNG full-capacity storage tank 1, the pump in the LNG tank 2, the BOG recondenser 3, the LNG sub-tank 4, the BOG compressor 5, the external transportation loading system 6, the second A regulating valve 7 , a second regulating valve 8 , a third regulating valve 9 and a fourth regulating valve 10 .

[0024] 2) The BOG produced in the LNG full-capacity storage tank 1 first enters the BOG compressor 5, and the BOG compressor 5 pressurizes the incoming BOG to increase the pressure of the BOG to 0.5MPaG-0.8MPaG, and then enters the ...

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