Field Development Optimization Technology

摘要

This paper describes the development and application of a new field development technology to optimize the locations of new and sidetracked wells within an oil or gas field, the drilling schedule, water and gas injection strategies, production/injection rates, and surface facilities. The field development plan optimization is informed using BP’s Top-Down Reservoir Modeling (TDRM) methodology. An economic indicator (e.g. net present value, incremental rate of return, capital efficiency, discounted payback, etc.) or oil/gas recovery is maximized subject to field development constraints. Only drilling targets in geologically defined areas are considered. Sidetrack wells are additionally limited by distance from their parent well. Drilling rig constraints (rig availability, drilling time, drilling costs, etc.) are incorporated. Economic constraints on project costs are also taken into account. Multiple integrated reservoir models, representing different combinations of sub-surface description and surface facilities, can be handled within this new field development optimization system. The system generates the optimum field development option by maximizing a percentile of either the selected economic indicator or the oil/gas recovery. Associated risks can be considered as constraints. Probability distribution functions of the maximized objective function and associated constraints are determined with a powerful optimization procedure developed using a combination of public and proprietary techniques. A large range of field development issues from well locations, drilling schedule, injection strategy and facilities modifications can be addressed. Applications of the developed technology for field development optimization in a giant new offshore oil field, and a mature oil field are presented. These applications clearly demonstrate that the new development optimization technology is a sufficien tly general tool for analysis to inform field development planning. Significant improvements in oil recovery, sweep efficiency, and net present value are demonstrated in the comparison with the reference field development cases.