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Smart Wells and Techniques for Reservoir Monitoring 255

7.4 SMART WELL APPLICATIONS

Control inflow of gas and water fluids: One of the main objectives of smart
wells is to control the early water or gas breakthrough for primary or sec-
ondary recovery. Horizontal wells are ideal candidates because water or
gas is mainly produced at the heel of well (due to the high-pressure drop).
An ICV or ICD helps reduce the pressure drop or at least equalize the pres-
sure across the lateral section. Water or gas can be controlled through time
per segment in the lateral section.
Control commingling wells: Produce multiple zones to produce vertical
wells. Smart wells enable exploitation of uneconomical production (one
well per interval) and acceleration of reserves. It is a practice that is very well
accepted by many national oil companies (NOC). The reserves per each res-
ervoir can be drained using one common wellbore but controlled indepen-
dently by using an ICV and packer per interval, as shown in Fig. 7.6. Any
individual layer that has water or gas breakthrough can be shut off or
controlled, which maintains overall oil cut.
Auto-gas lift injection: A gas interval zone in the upper section and oil in a
lower section can easily be completed using smart wells. An ICV can be set
up in the upper layers to control the necessary gas volume to lift the oil to the
surface. Also, the water zone in the upper section can be reinjected to the
lower section (with the oil) to reenergize the reservoir zone; this method is
called a controlled water-dump flood. Fig. 7.7 (left) shows typical examples
of auto-gas lift controlled at the surface.
EOR/IOR optimization: This is an area where smart wells could have a
significant contribution to increase the oil-recovery factor. With an

Fig. 7.6 Application of a smart well used to produce independent reservoir layers; the
production from each layer is commingled and produced through a single well.