Butt joint octagonal frustum type floating production storage and offloading system

A butt joint octagonal frustum type floating production storage and offloading system, comprising:

• an upper structural body in a regular octagonal frustum shape;
• a lower structural body in a regular octagonal frustum shape,
• wherein the upper structural body and the lower structural body are connected through their respective smaller bases at a junction plane to form a floating structure, and an axis of the upper structural body and an axis of the lower structural body are aligned,
• wherein the upper structural body comprises an upper hull, a center compartment I disposed inside the upper hull that has a same height as that of said upper structural body, and a plurality of watertight compartments disposed between the upper hull and the center compartment I,
• wherein the lower structural body comprises a lower hull, a center compartment II that has a same height as that of said lower structural body, and a plurality of watertight compartments disposed between the lower hull and the center compartment II,
• wherein a larger base of the upper structural body serves as a deck and a larger base of the lower structure body serves as a bottom of the floating structure,
• wherein the center compartment I and the center compartment II are hollow and are connected to form a straight shaft extending vertically through the floating structure from the larger base of the upper structural body to the larger base of the lower structural body, and
• wherein floating production storage and offloading system further comprises a plurality of support pillars disposed about an exterior surface of the floating structure, wherein an upper end of a support pillar is fixedly attached to the upper structural body at an upper attach point and a lower end of the support pillar is fixedly attached to the lower structural body at a lower attach point, and each individual support pillar and the axis of the floating structure are located in a same plane.