A method of selecting an injectate for recovering liquid hydrocarbons from a reservoir includes designing a plurality of injectates, calculating a net present value of each injectate, and selecting a candidate injectate based on the net present value. For example, the candidate injectate may be selected to maximize the net present value of a waterflooding operation.
STATEMENT OF GOVERNMENT RIGHTS
 This invention was developed under Contract DE-AC04-94AL85000 between Sandia Corporation and the U.S. Department of Energy. The U.S. Government has certain rights in this invention.