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Instrumentation and Measurement 63

2.2.2 Mature Assets
Mature assets are a special challenge for DOF projects because of older oil
field technology and lack of basic computer and technology infrastructure
(compared with the current standards). These older assets may not support
the instrumentation and automation that characterizes DOF systems. How-
ever, these assets may have enough hydrocarbon-producing life to warrant
the cost of retrofitting them with wellsite controls and automation.
The cost of sensors and infrastructure (for additional discussion, see
Chapter 9) is certainly a key obstacle. Wells are instrumented with pressure
and temperature sensors to support virtual flowmeters (Chapter 5) and arti-
ficial lift unit operations. High-rate wells in large mature fields (such as in the
Middle East) can often easily support downhole instrumentation and full
SCADA control platforms. For example, the KwIDF projects in Kuwait
supported MPFMs in a water injection area (Al-Abbasi et al., 2013).
In remote fields with large well counts but low rates, the trend is to use
local control facilities, which operate with solar-charged batteries and have
either WiMax or cell phone telecommunications. Furthermore, because
most of these mature wells require artificial lift (e.g., rod pump, ESPs,
and others), pump manufacturers offer pump-control packages that can
be used independently or that can be integrated with SCADA.

2.2.3 Deepwater Platforms and Floating Production Storage
and Offloading
These assets typically have high-volume wells and fields with considerable
infrastructure from the initial capital deployment. These assets usually oper-
ate like a refinery or petrochemical plant with full distributed control systems
(DCS) and onboard control rooms. Considerable instrumentation is
installed on the surface systems, subsea wellheads, and downhole.
Three evolving trends help these assets apply DOF. First is the applica-
tion of downhole temperature and pressure instruments used in each well.
This technology is becoming more common place as it has become less
expensive and more reliable. These instruments—together with nodal
analysis—allow users to perform real-time well surveillance and optimiza-
tion workflows.
One considerable limitation to applying DOF workflows in these fields
has been their relative isolation from support groups. Although the opera-
tions group is onboard the facility, the engineering and analysis teams are
usually onshore. These onshore groups have been limited in their ability