Method and system for offshore export and offloading of LPG

摘要

A process and system for directly exporting liquefied petroleum gas (LPG) from an offshore location is disclosed. The process comprises (a) obtaining a mixture comprising oil and natural gas from a subsea well; (b) separating LPG from the mixture comprising oil and natural gas at a floating or fixed offshore processing facility; (c) offloading the LPG directly from the floating or fixed offshore processing facility via subsea offloading risers and at least one subsea offloading flowline connecting the processing facility to a floating or fixed offshore transfer station; and (d) transferring the LPG to an export tanker at the transfer station. The system comprises a floating or fixed offshore processing facility, a floating or fixed offshore transfer station, and a set of subsea offloading transfer lines connecting the processing facility and the transfer station.

主权项

1. A method of directly exporting liquefied petroleum gas (LPG) from an offshore location, comprising:
a) obtaining a mixture comprising oil and natural gas from a subsea well; b) separating LPG from the mixture comprising oil and natural gas at a floating or fixed offshore processing facility; c) offloading the LPG directly from the floating or fixed offshore processing facility by delivering the LPG from the processing facility through a first subsea offloading riser down to a seabed, through a subsea offloading flowline at the seabed, and up through a second subsea offloading riser to a floating or fixed offshore transfer station; and d) transferring the LPG from the transfer station to an export tanker at the transfer station, wherein an intermediate floating production, storage, and offloading (FPSO) unit between the processing facility and the export tanker is not required, and with the method further comprising circulating the LPG in the subsea offloading risers and the subsea offloading flowline until the export carrier arrives at the transfer station.