Bonga deepwater field depends on sustained water-injection for reservoir pressure maintenance for efficient oil production. The field which lies 120km southwest Niger Delta in Nigeria at a water depth of 1000m, has varying flow rates in the producer wells with very fast response to changes in injection rates and has been developed with seventeen water-injectors to provide pressure support for the producer wells. All water injectors are fitted with subsea water-injection meters for measurement of actual injected water. The subsea infrastructure is such that the water injection wells are developed into two wings (Eastside and Westside) and serviced by two flow-header meters into each wing. Each wing consist of several water-injector wells, therefore measurement of water-injection into each well is crucial.
Since early 2011, the individual wells subsea water-injector measurement meters became faulty and we were unable to accurately measure the individual water injector's well rates due to the inconsistency of the subsea meter and efforts to fix the meters were not successful. As a result, the optimisation of oil production based on efficient water-injection was hampered because there was a high uncertainty of the water injection figures.
The proposed solution was to install Field ware Production Universe EOR, which is a state-of-the-art, real-time data driven application for water-injection monitoring. The procedure is to use a multi-rate injection well test from the bulk water-injection meter for data acquisition and build the Production Universe EOR model for subsequent rate estimation for individual water-injectors. The deployment of this application enhances efficient production optimisation effort in Bonga field through accurate measurement of the injected water into each injector well.
The result from this empirically based work shows how a quick solution for estimating water injection into each water-injector could be achieved. This reference tool could be applied to other operating units having similar challenges like Bonga field especially in a deepwater environment with high cost of intervention to replace such faulty measurement meters.