Abstract
The GAGD process was developed as an enhanced oil recovery (EOR) method that takes advantage of the naturally occurring gravity segregation of injected gas from crude oil, common in such processes as WAG. GAGD consists of placing horizontal producer wells near the bottom of the reservoir and injecting gas using (existing) vertical wells. It is proposed that the injected gas will rise to the top to form a gas cap while oil and water drain down to the horizontal producers. The work so far completed as part of the development of GAGD has encompassed a thorough literature review on the underlying mechanisms, selected scaled visual physical model experiments to confirm those mechanisms, and numerical simulations using commercial software to optimize the production configuration.
The final stage in the development of the GAGD process is the implementation in an actual field. To this end a detailed cash flow analysis will be performed in which selected economic indicators, such as the net present value, payout time, profit to investment ratio and rate of return, will be calculated for a specific Northern Louisiana field and given operating conditions. The operating conditions and resulting production profile have been optimized using numerical simulation and were used in the cash flow analysis. For the other input parameters, such as oil prices, capital and operational expenditures, and tax rate, the average values for Northern Louisiana will be used. The uncertainty in these parameters will be captured in a sensitivity study where their effect on the economic performance will be investigated.
