This paper discusses the application of black oil and multicomponent compositional models to simulate a gas cycling scheme at a rate of 140 MMCFD in the Bonnie Glen D-3A Pool. Considerable emphasis was placed on the matching of data derived from laboratory studies of reservoir fluid samples to ensure realistic predictions of phase behavior while cycling. The paper also illustrates the initial use of simplified models leading to larger more sophisticated models for the final prediction.
Results of the study indicated that a good match of phase behavior data was developed and so ensured a reliable prediction of gas cycling. Predictions indicated that cycling was technically feasible and that recovery of an additional 64,906,000 barrels of hydrocarbon liquid will occur over the life of the cycling scheme and subsequent blowdown. This simulation study formed the basis of an application filed with the Energy Resources Conservation Board of Alberta requesting approval to implement a gas cycling project in the Bonnie Glen Pool.
The Bonnie Glen D-JA Pool, discovered in January 1952, is located approximately 43 miles southwest of Edmonton. Alberta as shown in Figure 1. The reservoir. which forms part of the prolific Leduc Reef Chain, is one of the most capable producing fields in Canada. The original oil-in-place is estimated to be 657,138,000 stock tank barrels with an original gas cap of 444.900 million cubic feet. The recovery mechanism is primarily gas cap expansion and natural water influx with excellent gravity segregation from which an estimated 452,226,000 barrels of oil or 68.8 percent of the original oil-in-place will be recovered.
Since simultaneous production of the gas cap during the life of the oil column could be detrimental to oil recovery, gas cap production would normally be deferred until depletion of the oil column. Gas cycling however, can be carried out concurrently with continued depletion of the oil column with a beneficial effect on overall recovery of hydrocarbon liquids.
The Bonnie Glen Pool is a dolomitized, bioherm reef in the Leduc member of the Upper Devonian Wood bend Formation and is completely underlain by the Cooking Lake Formation. The reef, which forms part of the Leduc 0–3 reef trend, is approximately seven miles long, (WI) and one half miles wide at the original oil-water contact and less than one mile wide at the original gas-oil contact. Maximum original net pay thickness of the reef is 701 feet, of which 402 feet are gas cup and 299 feet are oil column. The Cooking Lake Formation is an active aquifer extensive in all directions except to the west:, where it pinches out almost immediately. The aquifer is common to other oil dud Has bearing accumulations in the same reef trend as shown in Figure 2 and interpool interference is evident by past pressure trends of the D-3 pools. Figure 3 presents a structure contour map of the top of the pool based on the gross reef section and Table 1 presents a summary of important reservoir parameters.