Nitrogen Separation Technologies: Best Served Hot or Cold?
Today’s market of sustainable high gas prices and dwindling reserves has caused producers to consider non-traditional sources of revenue generation. Once considered trash gas or a waste stream, high nitrogen reserves are now being reexamined as economically viable. In the past, smaller gas wells that tested high in nitrogen were simply shut in because the cost of producing such gas was not feasible. Today, however, advancements in technology, in both cryogenic separation and pressure swing adsorption and absorption have made nitrogen rejection a profitable reality, even for smaller gas streams.
In order to effectively evaluate the most applicable nitrogen technology available for a specific high nitrogen gas scenario, several factors should be considered. On the market today there are essentially three types of processing appropriate for nitrogen rejection; cryogenic processing (conventional cryogenic systems), the single column Nitech™ process, and non-cryogenic processing including pressure swing absorption, membrane systems, and lean oil adsorption. The differences in the competing technologies are substantial. In addition to upfront capital costs, the producer should also consider the following factors when selecting a valid nitrogen rejection technology for their gas processing demands.