Thermochemical Sulfate Reduction Prediction:

Title : THERMOCHEMICAL SULFATE REDUCTION PREDICTION:
Mitigation of Hydrogen Sulfide Risk in Petroleum ProductionSPEAKER: DR. GEOFFREY S. ELLIS,
Power, Environmental, and Energy Research Center, Division of Chemistry and Chemical Engineering, California Institute of TechnologyAbstract:Thermochemical sulfate reduction (TSR) is of increasing importance in both hydrocarbon exploration and production. On the exploration side, TSR can significantly affect the extent of oxidation of valuable resources, the maximum depth for oil potential, and the gas to oil ratio (GOR). From a production perspective, the toxicity and corrosivity of hydrogen sulfide require that costly H2S removal facilities be installed. As fossil fuel exploration progressively moves into marginal areas (e.g., deepwater offshore), the risk of encountering TSR will increase worldwide. Consequently, development of a tool for predicting the TSR risk of a given prospect is of great interest to the petroleum industry. We are combining experimental simulation with theoretical modeling in order to increase our predictive capability of TSR risk. Our experimental results suggest that while the temperature of the reaction is the most critical control on TSR reaction rates, the solubility of sulfate minerals, the ionic strength and redox conditions of the aqueous solution, the type of hydrocarbon oxidized, and the presence of reduced sulfur species and/or catalysts also significantly affect sulfate reduction. Several potential reaction mechanisms have been identified and the derivation of the kinetics of these reactions is part of our ongoing research. Additionally, diagnostic geochemical signatures such as the ƒÔ34S composition of H2S and the pattern of hydrocarbon cracking have been identified, and can be used to constrain model predictions.Location: Seeley G. Mudd Bldg., Room 101

Audiences: Everyone Is Invited

Contact: Evangeline Reyes