Browse Prior Art Database

Purification of Impure Nitrogen prior to its use for Enhanced Oil Recovery Disclosure Number: IPCOM000032047D
Publication Date: 2004-Oct-20
Document File: 1 page(s) / 21K

Publishing Venue

The Prior Art Database

This text was extracted from a Microsoft Word document.
This is the abbreviated version, containing approximately 86% of the total text.

Purification of Impure Nitrogen prior to its use for Enhanced Oil Recovery

Nitrogen is often injected into oil fields to increase or maintain pressure.  The specification of nitrogen for Enhanced Oil Recovery (EOR) is typically <10ppm O2. Depending on the application, impure nitrogen (about 1-2% O2) may be available as a by product from an Air Separation Unit (ASU).  Alternatively, the nitrogen may be most economically produced at low purity (again about 1-2% oxygen) using either cryogenic or non-cryogenic separation schemes.  In such situations, the nitrogen must be further purified to meet the EOR specification. 

Possible methods for oxygen removal from the impure nitrogen include: cryogenic distillation; ion transport membrane; conventional membrane; pressure swing adsorption; combustion or catalytic deoxidation with hydrogen, natural gas or any other suitable fuel.  Some of these methods may leave residual contaminants such as carbon dioxide, water or excess fuel in the stream which may be acceptable contaminants for EOR or which may be removed in a further processing step.

Typically, the nitrogen must be compressed prior to being injected into the well.  Such compression may occur prior to the purification step, after the purification step, or in combination

Any heat evolved in any of these processes may be used to raise steam and generate power or directly drive a compressor which may be a compressor to inject the resulting stream into an oilfield.

The impure nit...