Kirk Limbach, Ken Lew, Subodh Ganguly, Howard Evans, BOC USA, & Jack R. Blann, Jack Blann and Associates
The use of nitrogen to enhance the recovery of oil and gas reservoirs is becoming increasingly attractive. Recent examples highlight projects where large-scale nitrogen injection has been successfully implemented to increase both the production rate and recoverable reserves of oil and gas. Nitrogen-based techniques for improving oil and gas recovery include gravity drainage pressure maintenance, gas cap production, cycling of condensate reservoirs. attic oil production, driving gas for miscible slugs, and miscible nitrogen displacement. Methods for enhanced production employing nitrogen are discussed along with economics relative to the use of other gases, such as hydrocarbons or carbon dioxide. In many cases, project economics can be further enhanced by integration of the air separation (ASU) process with other processes on site (power plant, gas treatment, etc). The advantages of such an integration of nitrogen-based processes are discussed.