ABSTRACT
The removal (rejection) of nitrogen from natural gas is needed to meet pipeline specifications, to generate a nitrogen stream for enhanced oil recovery, or to provide a feedstock for helium recovery. This chapter compares three commonly used nitrogen rejection processes. It gives an overview of each process. The first process involves a double-column cryogenic distillation process. Typical operating conditions are given. Pressure swing adsorption is the second process. The third is a membrane process. The chapter provides an example of using membranes to upgrade the quality of a natural gas. The chapter then discusses enhanced oil recovery using cryogenic distillation.
