Hamworthy's hydrocarbon blanketing system eliminates the environmental damage and economic loss caused by emissions of gas vented to the atmosphere in a conventional process.
The purpose of the system is to replace the use of inert gas in FPSOs by pure hydrocarbon gas as a blanket gas in the cargo tanks, and to recover the off gas. The blanket gas prevents intrusion of oxygen into the cargo tank atmosphere, creating a closed system.
In loading mode, surplus gas from the cargo is recovered and recycled into the process plant by means of a blower/ejector/compressor.
In offloading mode, hydrocarbon blanket gas is supplied to the cargo tanks to maintain pressure in the cargo tanks. All the hydrocarbons are recovered to the process and emissions into the atmosphere are eliminated during normal operation.
Extensive work has been done to evaluate the implications of the technology on the operational and safety integrity of the FPSO concepts. Both theoretical studies and practical experience support the feasibility of the hydrocarbon blanketing concept. Hamworthy's hydrocarbon gas blanketing systems are already used on board several installations in the North Sea and West Africa.
