Staatsolie—the state oil company of Suriname—needed to
improve its production management for the Tambaredjo North West heavy oil
field. A swamp environment necessitates using amphibious rigs and service units
to drill and complete wells. Airboats are used to access over 100 wells and
related facilities. Because there was no SCADA system in the downhole gauges,
data retrieval was manual and time consuming. The 150-branch, 250-node network
suffered from bottlenecks, and back pressure was affecting progressive cavity
pumping (PCP) lift performance.
Staatsolie met with Schlumberger to discuss network management
improvements. A solution using PIPESIM production system analysis software was
outlined, including a redesigned header for flow transport, improved parameter
selection based on flowing emulsion viscosities to reduce backpressures, and a
multiphase booster pump design based on simulation results. Staatsolie
engineers would use PIPESIM software to simulate future field pressure
distributions, as well as flow efficiencies.
Modeling for insight and efficiency
Firstly, the team created a network model using PIPESIM software based
on 45 wells, and then gradually extended it to cover the 100-plus wells in the
field. Fluid properties were based on the limited pressure-volume-temperature
(PVT) reports available. Horizontal and vertical flow correlation sensitivity
simulations were run. Friction factors and liquid holdup measurements were
specified for the matching process with field production data.
The new pipeline model included field pressure matching, forecasted
volumes for future wells, visible pressure distribution, and maximum suction
pressure calculation. It also allowed engineers to optimize the placement of
pressure-relieving pumps, to alleviate bottlenecks. Network model results were
matched against total flow from the field, and the differential was found to be
within 5% of actuals each time.