Reservoir to surface Integrated Asset Modeling (IAM) is a cross-functional simulation, monitoring and decision tool. It captures the complex interactions all along the production / injection system of an oil or gas development. It is a powerful tool to maximize the value of an asset from the development phase to the end of the production period. This paper describes the successful work achieved for unlocking the challenging development of Absheron deep offshore gas condensate field through an integrated asset work and modeling.
The IAM has been the result of a multi-disciplinary and collaborative work where each disciplines, namely reservoir, well, network and surface process engineering, provided their inputs. A fully compositional fluid modeling was required to capture the challenges of such a long gas export production line with stringent thermal requirements due to the paraffinic content of the produced condensate, impacting at first order both plateau duration and economics. During all the pre-FEED engineering, attention was given to ensure consistency and synchronization between the IAM and the progress of the design work performed in parallel by each disciplines. Many sensitivity calculations on development parameters have been performed to quantify the impact of the geosciences uncertainties and other design parameters to define the optimum combination of production facility design, operating philosophy and monitoring strategy.
The first phase has been a screening with different production network design parameters associated to the base case reservoir model, namely the pipeline insulation and the arrival pressure.
The second phase has been to test the robustness of the proposed design towards reservoir base case uncertain parameters such as the well overall exchange coefficient, reservoir temperature, water break-through, fluid modeling and gas-water contact. The third phase has been to test the robustness of the proposed design towards low and high reservoir cases. All along these phases, many iterations and collaborative work between reservoir, well, network and process engineers occurred, all centered around the IAM offering the possibility to evaluate the production profiles associated to different designs assumptions while the different disciplines eventually performed more advanced "stand-alone" studies to further assess specific technical points.
The work performed for Absheron development highlights the benefits of integrated asset work and modeling to enable an economic development scheme robust towards uncertainties (petrophysical, structural modeling, water break-through…) and therefore not over designed