ALSC engineers review alarms for all measurements at the wellsite, and analyse summaries and poll data to identify likely causes of the events and quickly recommend remediation options via text message or email to the onsite crew for implementation. Critical events requiring immediate action can be communicated directly by phone.
In a move to provide both flexibility and fit-for-purpose solutions to meet operators’ unique requirements, the service encompasses four tiers -- visualisation, realtime surveillance and diagnostics, well optimisation and field optimisation.
Novel solution for depleted field
Agiba Petroleum implemented the production life cycle management service in conjunction with a unique artificial lift system in the Emry Deep field in the Egyptian Western Desert. Production in the field began in June 2012 with a startup rate of 4,300 bpd. Nine wells were then drilled, producing a total of 24,000 bpd from a sandstone reservoir primarily located in the Alam El Bueib formation.
During the development phase, average reservoir pressure began declining, from 4,070 psi to 2,450 psi. In an attempt to maintain reservoir pressure to improve recovery, Agiba Petroleum drilled a new water injection well, ED-16 ST, using two water source wells in the northern sector of the field. However, because the 16,500 bpd (2,623-m3/day) capacity of the available water source wells was insufficient to feed the new injector well, the operator needed to find an additional source of compatible water.
Two possible solutions were considered. The first was to simply drill another water source well, but the costs of drilling, completion and installation of flow lines encouraged the operator to seek a second alternative. This option involved use of a natural dump flood, giving the injector well access to both the injection and the higher-pressure, water-producing, zones of the field. By perforating both zones, a natural crossflow would occur, providing additional pressure.
Even in this scenario, however, the pressure difference between the two zones was not adequate to provide the necessary flow rate. Furthermore, an intelligent completion would need to be incorporated to control the flow rate between the two zones. Frequent production logging runs also would be required to determine the flow rate unless an expensive downhole flowmeter was installed.
To address these limitations, Agiba Petroleum collaborated with Schlumberger to engineer a new artificial lift system that would solve both the water supply and pressure issues. The end result involved installation of an ESP to produce the water from the higher-pressure upper zone and divert water back to the lower, injection zone through a bypass system, or reversed Y-tool. (Figure 2)