3 Validation Cases
A trio of validation cases is presented with field data comparisons. These include a 3-phase production separator, a gas plant suction scrubber and an FPSO separator motion study.
Validation Case 1: 1ST STAGE SEPARATOR CARRYOVER
Carry-over from a 1st stage separator was determined from data historian level trends for downstream suction scrubbers on two parallel compressor trains. MySep Studio predicted a mist carry-over rate of 12 litres/hr. This compared very closely with the measured rate of 11.7 litres/hr.
The 1st Stage separator is a horizontal 3-phase vessel, fitted with inlet cyclones and a mesh-type demister. The Suction Scrubbers for each of two compressor trains are equipped with a vane-type inlet devices and a mesh-type demisters.
Validation Case 2: GAS PLANT OPERATING LIMIT
The inlet separator on a gas plant processing 170,000,000 standard ft3/day has an inlet bend and a mesh pad demister. Light hydrocarbon liquid at inlet has low viscosity and surface tension giving rise to high inlet mist fraction which strongly degrades separation performance.
As the gas flow was increased MySep predicted that carry-over will take off at 170 MMSCFD. The operator confirmed that above this flowrate carry-over issues were indeed experienced in the facility.
Validation Case 3: MySep Motion Modelling versus CFD
MySep Studio modelling of vessel motion is compared with Computation Fluid Dynamics (CFD) simulation. Anti-sloshing baffles are use to suppress wave motion in separators installed on floating production facilities. The arrangement baffles requires design careful consideration. The MySep motion module captures the overall dynamic behaviour, tracking liquid levels as the vessel moves in response to the facility motion and flagging any operational concerns. Good agreement is demonstrated between CFD results and those of MySep Studio. A high degree of confidence in the value of this analysis to screen suitable designs can be inferred.