Insights into oil recovery mechanism by Nothing-Alternating-Polymer (NAP) concept

This paper introduces new oil recovery mechanisms for by polymer injection in heavy reservoirs with strong bottom aquifers. Due to unfavorable mobility ratio between aquifer water and the development of sharp cones significant amount remains unswept. To overcome these issues, case demonstrated this paper, a pilot was executed three horizontal injectors, located few meters above oil/water contact. The injectivity issues resulted frequent shutdowns injectors. Interestingly, cut reversal gain continued during shut-in periods. observation has led cyclic strategy, which is alternated intentional well shut-ins. strategy referred as Nothing-Alternating-Polymer (NAP). It found that injection, recovered conventional sweep enhancement ahead front. Additionally, stage injected squeezes existing creates barrier column, suppressing flux hence negative effect or channels (blanketing mechanism). Moreover, pushes depleted cones, then produced coming from period (recharge During NAP period, also bank leads extra production. resistance caused adsorption reduces extent fingering into bank. loss improves utilization factor expressed kg-polymer/bbl oil, resulting favorable economic outcome.