Field vs. Laboratory Polymer-Retention Values for a Polymer Flood in the Tambaredjo Field

Abstract

During a polymer flood, polymer retention can have a major impact on the rate of polymer propagation through a reservoir, and consequently on oil recovery. A review of the polymer-retention literature revealed that iron and high-surface-area minerals (e.g., clays) dominate polymer-retention measurements in permeable rock and sand (>100 md). A review of the literature on inaccessible pore volume (IAPV) revealed inconsistent and unexplained behavior. A conservative approach to design of a polymer flood in high-permeability (>1 darcy) sands would assume that IAPV is zero. Laboratory measurements using fluids and sands associated with the Sarah Maria polymer flood in Suriname suggested polymer retention and IAPV values near zero [0620 lg/g for retention and 0610% pore volume (PV) for IAPV]. A procedure was developed using salinity-tracer and polymer concentrations from production wells to estimate polymer retention during the Sarah Maria polymer flood in the Tambaredjo reservoir. Field calculations indicated much higher polymer-retention values than those from laboratory tests, typically ranging from approximately 50 to 250 lg/g. Field cores necessarily represent an extremely small fraction of the reservoir. Because of the importance of polymer retention, there is considerable value in deriving polymer retention from field results, so that information can be used in the design of project expansions.

Historical and recent observations in polymer floods: An update review

“…Tambaredjo field is a heavy (16°API and 300-1,100 cP) oil and relatively unconsolidated sandstone reservoir in Suriname (Delamaide et al, 2016; R., Mogollón, J. L., Bergwijn, S., Graanoogst, F., & Ramdajal, R., 2010; Manichand, R. N., Moe, K. P., Gil, L., Quillien, B., & Seright, R. S., 2013;Manichand and Seright, 2014;Moe, Manichand & Seright, 2012). Tambaredjo is described as a highly heterogeneous reservoir with a permeability contrast higher than 10:1 (T1 sand is a free crossflow reservoir).…”

“…Tambaredjo (Sarah Maria) polymer flood pilot area does not report active water drive or waterflood project. The pilot area consists of three 5-spot patterns (3 injectors and 9 offset producers) and the first well (1M101) started polymer injection in September 2008, the second injector (1N062) in May 2010 and the third (1M052) in June 2011 (Manichand and Seright, 2014). The injection strategy considered a variable injection rate (160-450 bbl/d) and an increase of polymer viscosity/concentration (45 cp @ 1,000 ppm; 85 cp @ 1,350 ppm and; 125 cP @ 2,300 ppm) over time.…”

Distribution and Presence of Polymers in Porous Media

“…Polymer retention can have a major impact on polymer-slug propagation and economics. Manichand and Seright [23] calculated that a 1240-ppm polymer solution exhibiting a retention value of 100 mg/g would require injection of 50% more polymer to reach a target distance in a formation (relative to the case for no polymer retention). They also reported field polymer (HPAM) retention values ranging from 50 to 250 mg/g for the Tambaredjo polymer flood in Suriname.…”

Operational Challenges and Monitoring of a Polymer Pilot, Matzen Field, Austria

“…Because the viscosity of the polymer solutions is substantially greater than that of water, polymersolution injectivity is lower than water injectivity. In addition, polymer solutions of high molecular weight show a significant increase of viscosity with flow velocity, and severe degradation of polymers occurs at high flow velocities, as observed in the nearwellbore region (Maerker 1975;Sorbie and Roberts 1984;Martin 1986;Gumpenberger et al 2012). To avoid high flow velocities in a radial geometry and achieve high-enough injectivity, injection of high-molecular-weight polymers is suggested above formation parting pressure (Seright et al 2009;Shuaili et al 2012).…”