Patent ID: 8490566

Claim:
A method for offloading a liquefied natural gas from a floating liquefaction vessel to a transport vessel for storage and transport to another location, the method comprising: a. using a connecting device connected to the floating liquefaction vessel to attach the transport vessel to the floating liquefaction vessel by: (i) using at least one ram connected between the floating liquefaction vessel and a telescoping walkway of the connecting device to move the telescoping walkway from a vertical transport position relative to a sea level to a horizontal deployed position relative to the sea level, wherein the telescoping walkway comprises an inner walkway slidably engaged within an outer walkway; (ii) connecting the telescoping walkway to a variety of bow configurations of transport vessels by securing a portion of the inner walkway to a portion of the transport vessel; and (iii) holding the transport vessel apart from the floating liquefaction vessel at a nominal distance, wherein the inner walkway extends and retracts from the outer walkway to accommodate wave action, wind effects, transport vessel dynamics, pitch, yaw, roll, surge, sway, and heave producing forces on the transport vessel and the floating liquefaction vessel; b. transferring the liquefied natural gas from the floating liquefaction vessel to the transport vessel using an offload flexible conduit on the floating liquefaction vessel in fluid communication with a walkway offload flexible conduit on the telescoping walkway; c. transferring personnel and equipment within an enclosed walkway formed in the telescoping walkway between the floating liquefaction vessel and the transport vessel; d. returning hydrocarbon vapor from the transport vessel to the floating liquefaction vessel using a walkway vapor return flexible conduit connected to the telescoping walkway and in communication with a vapor return flexible conduit on the floating liquefaction vessel, wherein the hydrocarbon vapor is formed during offloading of the liquefied natural gas from the floating liquefaction vessel to the transport vessel; e. using a transport vessel controller of the transport vessel to continuously monitor a member of the group consisting of: receipt of the liquefied natural gas, storage of the liquefied natural gas in the storage tanks, offloading of the liquefied natural gas from the storage tanks, and combination thereof; and f. dynamically positioning the transport vessel in proximity to the floating liquefaction vessel using computer instructions in the transport vessel controller and a member of the group consisting of: (i) motions measured by a motion sensor on the connecting device or the transport vessel; (ii) a fan beam laser-based positioning system on the connecting device or the transport vessel; (iii) a dynamic global positioning system on the transport vessel; and (iv) combinations thereof.