Block diagram of LNG process:
Key Process Units
SInlet Facilities (onshore):
Reception and
separation of offshore feed wet gas into gas, condensate, and water.
SAcid Gas Removal (AGR):
Remove acid gas (H2S
and CO2) by amine system ( Ucarsol
).
SSulphur Recovery Unit (SRU) / Acid Gas Injection (AGI):
Recover H2S and Mercaptans (RSH) into pure liquid Sulphur (Claus process), or inject the acid gas into onshore acid gas injection wells.
SGas Treating (Dehydration & SELEXOL):
Remove mainly water, Mercaptans (RSH) and Sulphur compounds from
saturated gas
SMercury Removal:
Remove mercury (Hg) form the dry
gas
.
SNGL Recovery:
Recover NGL (mainly C2+ or C3+).
SFractionation:
Recover Ethane (C2), Propane
(C3), Butane
(C4), also iso-Pentane (i-C5) and plant
condensate (n-C5+)
SRefrigeration:
Use Propane and Mixed
Refrigerant (MR) for gas pre-cooling and liquefaction.
SLiquefaction:
Liquefy the dry sweet gas by
Main Cryogenic Heat Exchanger (using
C3-MR).
