Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Single-stage fractionation of natural gas containing nitrogen

Patent ·
OSTI ID:6749765
Separation of natural gas containing nitrogen into a low-nitrogen fraction and a high-nitrogen fraction is achieved in a single distillation column in which reflux is provided by expanding the high-nitrogen with the performance of work and using the resulting refrigeration to condense vapor in the upper section of the column. Additional reflux is provided by vaporizing a recycle medium in heat exchange relation with vapor in the column. In-coming natural gas is passed in heat exchange relation with liquid in the column bottom, further cooled, and expanded into the middle section of the column. A helium-rich fraction may be separated from the high-nitrogen fraction. (8 claims)
Assignee:
Linde AG
Patent Number(s):
US 3797261
OSTI ID:
6749765
Country of Publication:
United States
Language:
English