Experiences With Waterflooding Lloydminster Heavy-Oil Reservoirs

Abstract

This paper compares observed and theoretical behavior of waterflood performance in heavy-oil reservoirs in the Lloydminster area of western Canada. Lack of reliable primary production history makes determination of primary recovery difficult and consequently makes additional oil recovery by waterflood difficult to quantify. Comparison of predicted and actual performance indicates that the floods are behaving as well as, if not better than, expected. Extra oil recovery by waterflood is not expected to add to the primary recovery of 3 to 8 % by more than 1 to 2 % of original oil in place (OOIP).

Effects of Solvent Properties and Injection Strategies on Solvent-Enhanced Steam Flooding for Thin Heavy Oil Reservoirs with Semi-Analytical Approach

“…The geometries and movements of the steam front and hot water front predicted by the proposed model are similar to the numerical simulation results, which also proves the reasonability of assumption (2). Figure 7 depicts the cold steam condensate front position at the end of the steam front spreading stage.…”

“…However, a considerable portion of the heavy oil resides in thin formations and in some countries more than 80% lies in reservoirs with a less than a 10 m pay zone; this has posed a major challenge for efficient development [2]. To date, the predominant in situ recovery methods for reservoirs with thin pay zone are steam injection by horizontal wells.…”

Viscosity Measurements of Different Fluids Used for Mobility Control in Mature Reservoirs

“…As wells mature, it is imperative that recovery efficiency is maximized [18]. During a water flooding study of heavy oil reservoirs in Canada, it was seen that halting water flooding operations decreased the water cut by 40% and increased oil recovery slightly [19]. Such issues can be solved through a reduction of fingering, improving sweep efficiency.…”

Optimized solvent-aided steam-flooding strategy for recovery of thin heavy oil reservoirs

“…In Western Canada, about 80% of heavy oil resources are found in reservoirs less than 5 m thick [1]. Although currently commercial thermal-based techniques such as Steam-Assisted Gravity Drainage (SAGD) and Cyclic Steam Stimulation (CSS) are successful for recovering bitumen and heavy oil from thick pay zones (>15 m), their application in thin heavy oil (<6 m) reservoirs are generally not thought to be economically viable.…”

“…Heavy oil cold production (CP) employs small energy input. However, the average recovery factor is typically low, usually, between 3% and 8% of the Original Oil In Place (OOIP) [1]. By employing the so called Cold Heavy Oil Production with Sand (CHOPS) technique, the recovery factor can reach as high as 15% [10].…”