| abstract |
An improved apparatus and process are disclosed for nitrogen rejection from a gaseous hydrocarbon stream recovered from an enhanced oil recovery project employing nitrogen for miscible flood of oil reservoirs. The process utilizes a modified dual distillation column arrangement including two fractionators which do not utilize overhead reflux condensers or reboilers for separating a nitrogen-methane mixture. Further, process conditions can be adjusted so as to provide efficient nitrogen rejection from a feedstream in which nitrogen content varies widely over a comparatively long period of time during enhanced recovery of oil. |