Tyrihans Subsea Raw Seawater Injection System

Abstract

StatoilHydro's Tyrihans field development is located about 22 miles (35 km) south of the Åsgard field on the Norwegian continental and the oil production will be substantially increased by raw sea water injection. The Tyrihans water injection system, currently manufactured and successfully tested, is the worlds most powerful subsea pump system and will have the longest step-out distance of 19.3 miles (31 km) to date. Two centrifugal pumps operate in parallel and have been verified by testing to be able to deliver a total shaft power of 7,340 hp (5.4 megawatts). The maximum injection capacity of the pumps is 126,000 bpd (20,000 m3/d) of seawater, without any filtration or chemical injection. During the last year, the subsea pump system has been through full load performance, endurance, stability and system integration testing at Tranby, Norway. The paper presents the pump system design including the pump modules, barrier fluid system, power supply, control and monitoring system. Data from the performance testing is included and discussed. System overview The StatoilHydro operated Tyrihans field is located on the Norwegian continental shelf approximately 22 miles (35 km) south of the Kristin and Åsgard B Platforms. Tyrihans will be developed with 5 subsea templates including oil production, gas injection and one raw seawater injection template (W). The subsea production system will be tied back to Kristin through a 16/18?? oil production flowline and receive gas for injection from Åsgard B through a 10?? gas injection flowline. Aker Solutions delivers the subsea raw seawater pump system and FMC was awarded the contract for the Subsea Production System for Tyrihans. StatoilHydro's contract strategy was to award this contract prior to awarding the contract for SRSWI and to invite the prequalified pump system suppliers to tender a pump system that could be lowered into the dedicated water injection template and controlled by the standard production control system.

Reassessment of Multiphase Pump on Field-Case Studies for Marginal-Deepwater-Field Devolopments

“…MPPs should be kept as close to the wellhead as possible so as to prevent separation in fluid phases because they flow through the pipeline and contribute to managing flow-assurance issues. According to Grynning et al (2009), MPPs are known to have a maximum step-out distance of approximately 30 km for longer distances. The procedure of using MPPs and boosting stations, as described by Abili et al (2012), can be applied.…”

Subsea Processing: A Holistic Approach to Marginal Field Developments

“…Raw Seawater Injection Pump (RSWIP) which was tested and has been successfully installed is the world"s most powerful subsea pump and is installed for a step out of over 31Km from the host platform 12 . It is a single phase electrically driven pump that can be leveraged on to cover 100km step-out distance.…”

Applying Subsea Fluid-Processing Technologies for Deepwater Operations

“…In an offshore environment, the produced water is either injected back into the formation or disposed of into the ocean. Gas/liquid-separation systems are normally used in conjunction with the subsea pumps to increase the energy-efficiency factor (Haheim and Gaillard 2009). Various subsea-separation designs are currently available for both two-phase and three-phase separation (Chiesa and Eriksen 2000), and separation techniques and technologies are discussed in the following subsections.…”