1. Reception of natural gas
Natural gas is received in liquid state transported in methane tankers at a temperature of -160º C from the liquefaction plants. The ships dock at the unloading dock of the regasification plant and the LNG is unloaded through three arms located on the quay.
LNG Liquefied natural gas
Gas 'BOIL-OFF' (steam)
Natural Gas
2. LNG storage
The LNG is transported through the ducts joining the arms to the storage tanks and is stored in these at a temperature of -160 º C.
LNG Liquefied natural gas
Gas 'BOIL-OFF' (steam)
Natural Gas
3. Management of gas boil-off
The addition of heat to the LNG (pumping process, solar radiation, transmission of heat from the foundation slab) causes a fraction of this to pass into the steam phase. This gas (Boil Off) is used to:
a. Compensate the displacement of the cargo originating from the process of unloading the tanker.. b. Go back into the process via the recondenser (after going through some compressors). c. To be injected into the plant's outlet pipeline when it is not possible to return it to the process.
d. Be burned in the torch when its elimination is not possible in some of the previous ways.
LNG Liquefied natural gas
Gas 'BOIL-OFF' (steam)
Natural Gas
a
b
d
c
4. Recondenser
A pumping system located inside the tank, known as primary, conducts the LNG to the recondenser, which acts as a liquid accumulator for the secondary pumps and allows the recovery of the Boil Off, incorporating it into the LNG stream.
LNG Liquefied natural gas
Gas 'BOIL-OFF' (steam)
Natural Gas
5. High-pressure pumping
The LNG from the recondenser is pumped at high pressure by a secondary pumping system, of similar design to the primary system, which drives the LNG towards the vaporisers.
LNG Liquefied natural gas
Gas 'BOIL-OFF' (steam)
Natural Gas
6. Vaporisation
The passage of liquid to gas is carried out in the seawater vaporisers. Through these, natural gas changes state when heated with seawater. A vaporiser, known as submerged combustion, used during periods of maintenance for the previously mentioned ones or in times of peak demand, where the LNG is heated and vaporised in a submerged burner which uses natural gas as fuel.
LNG Liquefied natural gas
Gas 'BOIL-OFF' (steam)
Natural Gas
7.Measurement and odorisation
The natural gas coming from the vaporisers is passed through a common collector to measurement and odorisation systems, and, finally, it is placed into the Basic Network of Gas Pipelines.
LNG Liquefied natural gas
Gas 'BOIL-OFF' (steam)
Natural Gas
8. Tank loading
The LNG can be loaded directly from the tanks into road tankers.
LNG Liquefied natural gas
Gas 'BOIL-OFF' (steam)
Natural Gas
9. Tanker loading (ships)
Using the primary tank pumps also makes it possible to reload the LNG into methane tankers.
LNG Liquefied natural gas
Gas 'BOIL-OFF' (steam)
Natural Gas
