ABB recently delivered process equip-ment to the Berge Charlotte FPSO, marking the successful first step in its new strategy for the turnkey supply of topsides process modules to floating production systems. The company already has a repeat order, with options for further deliveries. - ABB's delivery is prepared for transport from the company's Dusavik facility in Norway to Singapore.
For Berge Charlotte - which is to be renamed Sendje Berge - ABB has supplied a process system consisting of a 450-ton separation module with 60,000 b/d oil capacity, tie-in manifolds for reception of eight risers, a flair and ignition system with a knock-out drum skid, and a 9-ton control container. The company is also to participate in the hookup and commissioning of the equipment, and is responsible for operating and maintaining it for a period of three-five years.
The order was placed by the vessel owner, Bergesen Offshore, which has been contracted by Triton Energy to produce the La Ceiba Field offshore Equatorial Guinea, West Africa. The vessel is being converted to a production ship at the Jurong yard in Singapore, and is due to sail for the field in September. There may be further work for ABB on this project - Triton sees upside production potential in La Ceiba which may require the expansion of process capacity and the addition of water injection and gas compression facilities.
ABB Offshore Systems already has a track record for supplying equipment to production ships. Recent deliveries have included a seawater filter to Petrobras's P-37 floater, a water injection system, a produced water system, and utility packages to Norsk Hydro's Varg ship, and a de-oiling hydrocyclone skid to Texaco's Captain FPSO.
But the Sendje Berge order takes business onto a new plane. "From process skids, we now want to develop into a process house, with an emphasis on environmental aspects and cost efficiency, achieving this through the development of new technology," says Mikkel Martens, Senior Vice President at ABB Offshore Systems.
When it comes to production ships, with the exception of fabricating the hull, ABB can supply almost everything for the marine, process, and power generation sides, and for the supply and installation of risers and moorings, and can act as the total topside system integrator, Martens says. One key-word in the offshore industry nowadays is flexibility, and according to Martens ABB has put particular emphasis on developing flexible process systems for marginal fields that can be expanded if and as required in the light of developing reservoir knowledge. In the case of Sendje Berge, production capacity could be doubled to 120,000 b/d, or even quadrupled to 240,000 b/d, according to Triton President James C. Musselman.
Given the worldwide nature of many deliveries, ABB's global presence is also an advantage, Martens says. In the Sendje Berge case, the equipment is installed on a Norwegian owned vessel which is under conversion in the Far East and will work in West Africa for a US oil company working out of the US. ABB's familiarity with the certification systems and approval regulations involved in the relevant countries eases and speeds up the task.
If the company is to succeed in its aim, however, it has to be able to deliver in a reasonably short period and at a reasonable cost. Martens recognizes that too often in the past, field development has taken too long and cost too much. The delivery period for Sendje Berge process modules was only nine months. This is partly because the company was already engineering a generic process system for the vessel when Bergesen won the La Ceiba contract. The fact that work was already in hand, thus shortening the delivery period, worked to Bergesen's advantage. And because of the requirement for the process system to be flexible, and therefore fairly generic, comparatively little re-engineering was needed.
As a VLCC with a deadweight of 275,000 tons and 2 million bbl storage, the Sendje Berge does not present the same space and weight restrictions as a fixed platform. The vessel is 350 meters long and 50 meters wide, allowing the control container to be sited well away from the process module. There will be no difficulty in accommodating additional process equipment if necessary. The flowlines coming over the side are also well separated.
Bergesen provided a functional specification for the process equipment. This gave ABB the freedom to design the system from scratch, undertaking technology development as required to overcome operational problems it had identified. One of these was foaming and clogging which commonly occur at the inlet of some separators. To resolve this, it used an inlet device based on an idea from Norsk Hydro and developed together with that company, which acts as a momentum breaker, diminishing the shear forces so that retention time in the separator is minimized. The same device is used on the Troll Pilot subsea processing system supplied to Norsk Hydro in Norway. A second generation of the device has been developed which is now being tested.
Other relevant technology developments include an in-line compact electrostatic coalescer and the Codeflo system for achieving enhanced separation quality of down to 10 ppm for produced water.
The Sendje Berge delivery was done out of Norway, with engineering performed at Billingstad and the equipment assembled at the company's Dusavik facility near Stavanger. The control module was supplied by ABB Industri in Oslo. It was important for close control to be exercised over the first delivery, says Martens.
Work is commending on the second order, which again will be delivered in nine months. This is for Berge Hus, another Bergesen VLCC to be converted to a production ship in the Far East. Now having a grip on the delivery of such a system, ABB has this time placed the order for the process module with ABB Thailand, which uses the local fabrication company STP&I. This will bring down the cost of supply and reduce the time taken to transport it to Singapore, Martens says.