A Comprehensive Review of H2S Scavenger Technologies from Oil and Gas Streams

Sour crudes containing >0.5% sulfur are of low quality and cause harm to equipment, the environment, and to humans. Therefore, sustainable measures for crude oil sweetening are of significant importance. Removal of H2S directly at the wellhead before the transport increases the value of crude oil and may be necessary to adhere to legal transport laws. Chemical agents known as scavengers are used to scrub H2S from crude oils. Scavengers are either of the regenerative or non-regenerative type and are used depending on the pH or water content of the crude stream. The literature has been surveyed to reveal those absorbents that allow the most effective scavenging of H2S at wellhead applications. The chemical processing, including recovery of scavenger or end use of products, is discussed for decision-making at the confluence of chemistry and chemical engineering for H2S removal. This work investigates how and why some scavengers perform better for some crudes and environmental conditions than others with the intent to develop designer scavengers and processing conditions for the crude oil industry.