MFA Control and Optimization
of Crude Oil Separators
MFA control of oil levels to balance
the material flow in multiple vessels.
||• To ensure that all capacity in a 3-phase
crude oil separator is being used so that the process
throughput is maximized without any trips occurring.
control of water levels to maximize vessel capacity
and prevent leakage.
||• Automatically control critical oil level,
water level, and pressure loops in all operating
conditions and eliminate the need to manually re-tune
the controller parameters.
MFA control of gas pressure to handle
slugs and reduce gas waste.
||• Quick return-on-investment (ROI).
Crude Oil Separator MFA Control and Optimization Solution
Process: A typical onshore
or offshore 3-phase oil separator train consists of
2 separator vessels with or without a slug catcher.
Crude oil consisting of water, oil, and gas is separated
through the system.
Control Problems: Each vessel is typically
controlled as a standalone unit. There are instances
where a high level trip in one of the vessels has occurred
while there is spare capacity in the other vessel. Also,
the gas pressure loop is nonlinear in nature and a random
slug can cause the pressure loop to swing resulting
in frequent ignition of excessive gas.
Solution: This is a combined control
and optimization problem. CyboSoft offers an effective
solution for controlling critical level and pressure
loops and maximizing the separation capacity.
Water Level Control: Robust
MFA controllers are used to control the
Water Levels. This allows a lower setpoint setting leaving
more storage room for the Oil Level. A lower bound on
the Water Level PV prevents the level from dropping
too low which might cause oil leakage.
Pressure Control: Nonlinear
MFA controllers are used for the pressure
loops. They can effectively deal with gas loop nonlinearity
and slug problems with easy configuration since nonlinear
characterization is not required.
Oil Level Control: A MIMO
MFA controller is used to control the oil
levels in a multivariable control fashion. It can coordinate
the related oil levels by simultaneously manipulating
the related oil valves to prevent too high an oil level
in one vessel while there is still storage room in others.
This special MFA can balance the oil levels for both
vessels to maximize the vessel capacity usage.
Conclusion: This solution can be delivered
in either the CyboCon
software or a CyboCon Dragon Micro distributed
control system depending on the interface and integration
needs. Since no process models are needed, commissioning
and maintenance of the system is simple with guaranteed