Abstract
An alkaline-surfactant-polymer flood was implemented in the Tanner Field, Campbell County, WY, after waterflooding to a 43% oil cut. Tanner is a Minnelusa B sand with one injection well and two production wells. Primary production began in April 1991 with a waterflood starting in October 1997. Peak waterflood production reached 19,000 bbls oil per month in February 1999. Waterflood continued through April 2000 at which time oil production had declined to 9,500 oil bbls per month at an oil cut of 43%. In May 2000, an alkaline-surfactant-polymer solution was injected. A solution of 1.0 wt% sodium hydroxide plus 0.1 wt% active ORS-41HF plus 1000 mg/L Alcoflood 1275A dissolved in Fox Hills water was injected through January 2005. A tapered concentration polymer drive began in February 2005. Oil recovery through December 2005 is 1,013,944 bbls from the total field and 874,490 bbls from the floodable pore volume or 44% OOIP. Incremental oil to date is 199,670 bbls or 10% OOIP. Projected ultimate oil recovery is 65% OOIP. Ultimate waterflood oil recovery was calculated to be 48% OOIP. This paper will discuss all aspects of alkaline-surfactant-polymer flood implementation from the laboratory evaluations to the field.
