Traditionally sour gas high in carbon dioxide (CO2) and hydrogen sulfide (H2S) have been ignored due to the technological gaps and high costs associated with processing it. Both components must be removed before the gas is saleable: H2S is both flammable and toxic, and both are corrosive to transportation infrastructure. Yet as technology progresses, some extraction companies are taking greater risks and making bigger investments in infrastructure. The Shah gas field project in Abu Dhabi, for example, is expected to reach full production levels later this year, built to handle H2S levels near 23 percent and CO2 levels near 10 percent. The design and construction of that facility had to overcome “recovery of sulphur on an unprecedented scale, as well as other processing and transportation issues to deal with the highly corrosive material.”

These sorts of projects are often driven by advances in metallurgy. Take for example Peter Coe, technical director at U.K.-based Charles Thompson Ltd., who is frequently tasked with the daunting effort of fabricating exotic alloys and special welds for sour gas processing projects. Some alloys Coe works with like Alloy 625 are “sensitive” and very purpose-specific. Others are very experimental and undergo rigorous testing. “We weld these exotics using various appropriate processes to achieve highly satisfactory results,” Coe told Pipeline Magazine in late 2014, “and the welds are fully mechanically and chemically tested to validate our procedures.”

Another area of materials development is occurring with separation membranes, which are an alternative to solvents and adsorption techniques. High-performance membrane research is happening in universities and labs around the world, including the Georgia Institute of Technology and Texas A&M, where professors Jaime C. Grunlan and Benjamin A. Wilhite created a new polymer-based membrane material that is relatively cheap to produce. The polymer coating can be sprayed on a material, or the material can be dipped in the coating and be applied towards sour gas processing.

Another type of gas processing technology is in the works, this time for capturing and processing CO2 from flue gas originating from fossil-fuel burning power plants.  An amine-based solvent (OASE blue) is being used in conjunction with advanced CO2-capture technology to help power plants capture and ship it off for safe transport while meeting a Department of Energy goal of 90 percent capture. The OASE solvent is introduced into an absorption column at low temperatures to capture the CO2. It’s then stripped in a special column, resulting in pipeline-quality CO2.