This presentation provides a technical overview of a project aimed at evaluating the feasibility of Enriched-gas injection by using a small well distance in the later period of the pilot tests. The advantage of a small well distance is that the initial and peak production responses can be reached early. Thus, the feasibility evaluation could be initiated sooner. Pilot tests in two areas were conducted. The first pilot test was performed by continuous gas injection in area IA with well distance 250 meters. The purpose of this test was to evaluate the effect of the continuous enriched-gas injection on the relative high permeability layer IV. The second pilot test was carried out in area IV using WAG process with well distance 150 meters. The goal was to see if WAG can enhance oil recovery by injecting into and producing from layers II, III, and IV simultaneously. The implementation for IA area was stopped due to solvent breakthrough after 112 days of operation. The oil recovery was increased by 8.9% compared with water flooding. The other pilot test in IV area is still in operation. A numerical simulator has been used to predict the oil recovery after matching production performance. The oil recovery is significantly lower than that in IA area because of faulty perforations in the main producing layer IV. However, compared with water flooding, an encouraging increment by 5.39% can be obtained by deducting layer IV’s OOIP. These results show that both continuous injection and WAG process can improve oil recovery significantly. The numerical simulation study showed that a large well distance can also increase oil recovery in both of the testing areas. Further tests with the wells at larger distance may be performed in the future.

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