Oil and gas production handbook - Process Control and ...

The system is operated from
the Central Control Room
(CCR) with a combination
of graphical process
displays, alarm lists, reports
and historical data curves.
Desk screens are often used
in combination with large
wall screens as shown on the
right. With modern system
the same information is
available to remote locations such as an onshore corporate operations support centre.
Field devices in most process areas must be protected not to
act as ignition sources for potential hydrocarbon leaks.
Equipment is explosive hazard classified e.g. as safe by
pressurization (Ex.p), safe by explosive proof encapsulation
(Ex.d) or intrinsically safe (Ex.i). All areas are mapped into
explosive hazard zones from Zone 0 (Inside vessels and
pipes), Zone 1 (Risk of hydrocarbons), Zone 2 (Low risk of
hydrocarbons) and Safe Area.
Beyond the basic functionality the control system can be used for more advanced
control and optimization functions. Some examples are:
• Well control may include automatic startup and shutdown of a well and/or a
set of wells. Applications can include optimization and stabilization of
artificial lift such as Pump off control and Gas lift Optimization.
• Flow assurance serves to make sure that the flow from wells, in pipelines
and risers are stable and maximized under varying pressure, flow and
temperatures. Unstable flow can result in slug formation, hydrates etc.
• Optimization of various processes to increase capacity or reduce energy
costs.
• Pipeline Management modeling, leak detection and pig tracking
• Support for Remote Operations, where facility data is available to company
specialists located at a central support center.
• Support for remote operation where the entire facility is unmanned or
without local operators full or part time, and is operated from a remote
location.
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