An Evaluation of Reinjection into Geopressured Reservoirs

Abstract

Data from five geopressured reservoirs were evaluated to determine energy requirements and total production enhancement resulting from reinjection of spent brine into the producing formations. Thermal and hydraulic energy availabilities of the produced brines were compared to injection energy requirements to assess the viability of deep reinjection. Production lifetimes possible using deep reinjection were then compared to those attainable from primary pressure depletion mode of reservoir utilization to enable assessment of total methane recovery enhancement via deep reinjection. For the reservoir cases studied thermal and hydraulic energy availability ranged from 70 to 100 percent of energy required for deep injection. Total methane recovery via a production/deep reinjection scheme was three to ten times that possible via primary pressure depletion production.