Flow management and oil recovery rates in subsea production installations are not optimal, partly due to failure to measure parameters such as salinity in single well streams. Variations in salinity will incur offsets in oil and gas volume data from subsea multiphase flow meters (MPFMs), and may also indicate water breakthroughs, in which the wells starts to produce injected sea water. Both these effects bring about considerable losses for the operator. The number of subsea installations is steadily increasing and the problem is therefore felt in the industry. The only method today for checking salinity in individual well streams involves ROV intervention, a hugely expensive operation. The Idea is to develop a sample and analysis system for installation upstream from MPFMs on subsea manifolds. Integrated in the flow line, the system will sample the multiphase production from the well, allow the fluid to separate into its single phases by electrostatic coealescing and measure the salinity of the water fraction.
By monitoring the salinity, the MPFM may be regularly calibrated and the offset is removed. Salinity measurements will also enable early detection of water breakthrough, where wells start to produce injected sea water instead of oil. The system will: - Improve accuracy of MPFMs by removing errors caused by variations in salinity - Enable early detection of water breakthrough through detection of said variation in salinity - Verify MPFM data by volume fraction estimation in sample separation tank SalinityScan will involve extensive development work in several research areas, including oil separation technology, ultrasound level gauging, control electronics, mechanical design and subsea instrumentation. A large market has been identified for the introduction of the SalinityScan system. It is anticipated that the participating SMEs will gain valuable experience and great economical benefits through the completion of this project.