Problem Hydrogen Sulfide in Fuel

Catalytic cracking, coking, visbreaking, and other high-temperature refining processes can liberate sulfur from crude oil or from a process stream. Once free, sulfur can react to form low-molecular-weight compounds such as hydrogen sulfide, methyl mercaptan, carbon disulfide, and others. 

Hydrogen sulfide is a poisonous, flammable gas that can contaminate and dissolve in process fractions, especially residual oils. It is also soluble in water that may be dispersed in these same residual oil streams. 

Severe hydroprocessing to remove sulfur from naphtha and distillate fractions produces hydrogen sulfide. Although most hydrogen sulfide is removed as off-gas or stripped from fuel streams, the possibility exists for low levels of hydrogen sulfide to remain in fuel fractions. 

Sulfate-reducing bacteria (SRB) can live in water bottoms of fuel storage tanks. These bacteria can produce growth plaques on metal surfaces and can live in corrosion pits in metal. Hydrogen sulfide is a product of SRB metabolism and can contaminate fuel stored in tanks. 

Components of Fuel and Fuel Additive Storage and Injection 

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