A perspective on dual purpose gas hydrate and corrosion inhibitors for flow assurance

In oil, natural gas processing and transmission, gas hydrate blockage and corrosion are two major flow assurance problems associated with transportation through steel pipelines which lead to severe safety and economic losses. To overcome these flow assurance problems in subsea flowline, industry is injecting different types of gas hydrate as well as corrosion inhibitors. However, the injection of these chemicals has a counter or side effect on inhibition performance in the pipeline. Moreover, these chemicals demand large infrastructure such as storage tanks, a complex regeneration process, injection pumps, and subsea distribution pipelines. In addition, presence of electrolyte ions in the formation water may induce operational issues such as scale deposition and hydrate inhibitor loss. The mechanism, types and applications of gas hydrate and corrosion inhibitors in gas industry have drawn much attention but dual purpose gas hydrate as well corrosion inhibitor (GHCI) behavior or performance is less discussed in open literature. This review paper discusses the essential concepts of hydrate and corrosion formation, occurrence and recent methods employed for hydrate and corrosion mitigation along with literature review on recent experimental studies on gas hydrate and corrosion inhibitors (GHCls). The challenge of application of GHCl and understanding the chemistry of various salts and ions is presented. Future prospects of dual purpose GHCIs for gas industries are also discussed briefly.