FPSO Jiskoot has developed a solution for the blending of heavy crude oil in the Gulf of Mexico for Bergesen Worldwide Offshore, using the latest InSight blender system

FPSO Jiskoot has developed a solution for the blending of heavy crude oil in the Gulf of Mexico for Bergesen Worldwide Offshore, using the latest InSight blender system on the BW Enterprise floating production, storage and offloading vessel, which will reportedly be the world's largest FPSO when its conversion from the 360,000 dwt ULCC BW Enterprise at the Sembawang shipyard in Singapore is completed. The FPSO will serve as a hub in the nine-platform Pemex KuMaZa development of the Ku, Maloob and Zaap fields and act as an export terminal, receiving unstabilised oil for stabilisation and blending it with stabilised oil. First oil is scheduled for early 2007.

Accurately and economically blending the produced heavy 13 API crude oil with lighter 21-35 API crude to optimise the value and specification of the export crude, the system is a two-stream blender with on-line density measurement designed to accurately blend a 16-21 API crude oil at up to 800,000 barrels per day.

Providing user-friendly control, measurement and reporting of the whole blending process, the InSight blend controller uses on-line measurement to continually optimise final product quality.

By being integrated with the FPSO's Emerson DeltaV control system, the real-time non-PLC control system also achieves a second key project objective of implementing a maintenance on demand system on the entire vessel.

To guarantee accurate density measurement and ensure that the final product is homogeneous, a JetMix system used in the blend header is unique in that it mixes across a wide range of flow rates with no pressure drop.

This, along with ultrasonic flow meters and careful component selection, allows blender design to be optimised for a maximum pressure drop of less than 1.5 bar.

Flow-weighted averaging and 3-term PID control ensure that the blended product is on specification at all times during the batch, with unique control algorithms responding instantly to changes in process conditions or quality.

The batch is continuously measured and feedstocks adjusted to optimise quality and minimise 'give-away'.

The system is designed to ensure consistent quality throughout the batch even during quality variations, feedstock starvation and loss of power or the unlikely failure of a system component.

A facility to automatically increase throughput enables crude to be blended at the maximum available component rate to optimise the batch production time.