Canyon Express Field Performance Simulation
Authors: Wallace Bryan K. , Gudimetla Ravi 
Published: October 2008

The Canyon Express development is a three operator (TotalFinaElf, BP, and Marathon Oil Company) subsea development consisting of the transport of gas-condensate from deepwater (~7000 feet) subsea reservoirs to a host platform via dual 47-mile 12-inch nominal OD flowlines. The three developments are Camden Hills (Marathon, Pioneer Natural Resources USA, Inc., and TotalFinaElf), Aconcagua (TotalFinaElf, Pioneer Natural Resources USA, Inc., and Mariner Energy, Inc.) and King's Peak (BP). The operation of the Canyon Express development involves ultradeepwater reservoirs from three individual operators flowing into a common subsea, multi-phase gathering system. To optimize and equitably establish the operation of the Canyon Express system over the life of the development, it was necessary to integrate the respective reservoir models from each operator with the thermal-hydraulic steady-state model for the dual flowlines while considering reservoir decline, production liquids, methanol injection, topside facility constraints, and decreasing host platform arrival pressure.

To simulate the normal operation of this development, a steady-state reservoir and flowline simulation using Baker-Jardine's Field Planning Tool (FPT) and PipeSim-Net was performed. The system operation was simulated over the field life using basic reservoir modeling and decline via tank models for each reservoir while considering host facility (e.g. platform compression, host platform arrival pressure, well production rates, etc.) limitations. The integrity of the reservoir tank models used in the flowline simulations was verified by comparison with results from the respective reservoir simulations for the three fields. The focus of this work was to assist in the determination of the strategy to maximize recoverables and determine each operator's volume allocation and excess capacity over time.

Introduction

TotalFinaElf, BP, Marathon Oil Company, Pioneer Natural Resources USA, Inc., and Mariner Energy Inc. intend to jointly develop three deepwater fields in the Gulf of Mexico region. The fields are the Marathon-operated Camden Hills in Mississippi Canyon (MC) 348 block, TotalFinaElf-operated Aconcagua in MC305 block, and BP-operated King's Peak in DeSoto Canyon (DC) 133, DC177, and MC217 blocks. The production consists primarily of methane gas with varying volumes of water and condensate. Methanol is to be injected at the wellhead for hydrate inhibition. Maximum production rates from each field range from 100 to 225 MMSCFD with approximately 200 to 450 BPD of condensate, 300 to 900 BPD of water, and 450 to 1400 BPD of methanol.

The production from the wells will be transported via twin 12-inch nominal O.D. flowlines from the Camden Hills field at approximately 7200-foot water depth, to the Aconcagua field at approximately 7050-foot water depth, then to King's Peak field at approximately 6600-foot water depth, and finally to a host platform fixed structure located on the continental shelf. The twin flowlines form a piggable system via a loop connecting the two flowlines at the flowline ends. The flowlines are separated by a pigging valve, which will remain closed during the normal operation of the system. Thus, the flowlines will operate independently of the other. The flowline tie-ins of the wells are as follows: