OPTIMAL PLANNING AND SCHEDULING OF OFFSHORE OIL-FIELD INFRASTRUCTURE INVESTMENT AND OPERATIONS

A multiperiod mixed-integer linear programming (MILP) model formulatio n is presented for the planning and scheduling of investment and opera tion in offshore oil field facilities. The formulation employs a gener al objective function that optimizes a selected economic indicator (e. g., net present value). For a given planning horizon, the decision var iables in the model are the choice of reservoirs to develop, selection from among candidate well sites, the well drilling and platform insta llation schedule, capacities of well and production platforms, and the fluid production rates from wells for each time period. The formulati on incorporates the nonlinear reservoir performance, surface pressure constraints, and drilling rig resource constraints. The resulting MILP model contains several thousand binary variables and is intractable u sing a full space branch and bound technique. A sequential decompositi on strategy using aggregation of time periods and wells, followed by s uccessive disaggregation, is proposed. Two examples are presented to i llustrate the performance of the algorithm.