The Kuparuk River oil field has had a "miscible" water-alternatinggas (MWAG) enhanced-oil-recovery (EOR) pilot in place since 1988. This original pilot was implemented on two drillsites previously on waterflood. The pilot was expanded to a third drillsite in 1993 to test the MWAG process in an area previously flooded by an "immiscible" water-alternating-gas (IWAG) recovery technique. Large-scale application of MWAG at Kuparuk is in progress, with a project that will more than triple current MWAG injection. Full implementation is slated for mid-1996. When completed, the Kuparuk large-scale EOR (LSEOR) project will be among the largest of its kind in the world. This paper covers the basic aspects of moving the EOR process at Kuparuk from pilot to large-scale application. A number of hurdles had to be overcome, including scaleup of field and simulation results in a consistent manner and the need to use existing infrastructure to ensure economic viability.

A methodology is provided for analyzing high temperature and high pressure reservoir fluid samples directly on a gas chromatograph. Coupled with a procedure for concentrating the heavy end fraction of lean gases, the methodology is extended to samples containing as little as 1 wt % C6+. Analysis of example fluids demonstrates relative precision and accuracy of 97% for most components when present in significant concentrations. For lean gases, errors of &lo% are demonstrated for heavy end components of samples with 2-8 wt % C6+. The methodology has been successfully applied in estimation of condensate reserves and gas cycling studies.The techniques and conclusions presented in this paper are those of ARCO Oil and Gas and ARCO Alaska, Inc. and may not reflect those of the other Working Interest Owners of Prudhoe Bay.