Exploring New Concepts in Subsea Field Architecture

The present paper will explore an alternative subsea system configuration where it is possible to install dedicated equipment for each well (or group of wells) depending on its particular needs (e.g. boosting, separation, metering). This could allow achieving efficient and optimal management of the integrated system over the entire life of the field. Additionally, it opens for opportunities to optimize the operation of equipment and the utilization of resources. To test the concept, a field life study was performed on a conventional subsea oil field using a commercial software for modeling of production systems. The reservoirs were represented using a material balance model, and well rates are calculated considering the pressure drop and pressure increase (boosting) along the production system. Three cases were simulated and compared in terms of their cumulative oil production and power consumption when subsea processing is required. Case 1) standard configuration of pipeline- riser system without subsea processing unit, case 2) including a single subsea booster in the original network system, and case 3) including a modular assembly with boosting capabilities to individual wells. From all the evaluated cases, Case 3 showed the highest cumulative oil production at the end of field life. Two production strategies were tested for case 3: System demand (boosting units starting up at different times according to wells requirement) and simultaneous running mode (all boosting units starting up simultaneously). The different production strategies influence the potential for system improvement in terms of the process efficiency, production rate, and power demand.