Technologies Comparison for Separation of CO2 and H2S from Oil/Gas within the Reservoir
Special Symposium - EPIC-1: European Process Intensification Conference - 1
EPIC-1: Poster Session (EPIC - Poster) - P2
Keywords: separation, CO2, H2S, absorption, membrane
Crude oil and hydrocarbon gas streams may contain high levels of CO2 and/or H2S as contaminants. Opportunities for disposal of the unwanted components include subsurface sequestration of these substances. With the cheaper oil and gas reservoirs being produced, more difficult and, hence, more expensive fields are targeted for production. It is clear that sour gas gives rise to extra costs and potential environmental hazards.
It is desirable to prevent any contaminant to reach the surface, or to considerably reduce the contaminant levels reaching surface facilities. The technologies here considered for the separations are membranes, absorption/extraction, and cryogenic separation. On basis of operation conditions and volume limitations different technologies are compared with each other with their advantages and disadvantages.
Membrane materials for the separation of CO2/CH4 and H2S/CH4 are screened, which are stable under downhole conditions (100-300 bar, 50-100 oC) and moreover are stable to the natural gas impurities, for example H2O1, and higher hydrocarbons2. Zeolite membranes, for example type DD3R, were identified as potential candidates.
At the same time absorption/desorption processes for the treatment of natural gas and extraction processes for oil fields were elaborated. The distinct advantage of the fluid processes is the robustness under severe conditions of the reservoir. There are different choices for the solvent selection, strong chemical absorbents, mildly basic aqueous electrolyte solutions3 and organic (physical) solvents4.
1. D.C.Calabro; S.E.Jakubowicz; C.J.Yoon; T.E.Clark; H.W.Deckman; R.R.Chance; Bonekamp, B. C.; P.P.A.C.Pex, Intrinsic Gas Transport and Water Stability of Silica Membranes for CO2/CH4 Separations. ECN-RX-04-083(the ICIM 8 conference in Cincinati, Ohio, USA) 2004.
2. Li, S.; Alvarado, G.; Noble, R. D.; Falconer, J. L., Effects of Impurities on CO2/CH4 Separations Through SAPO-34 Membranes. Journal of Membrane Science 2005, 251, 59-66.
3. Benson, H. E.; Field, J. H.; Haynes, W. P., Improved Process for CO2 Absorption Uses Hot Carbonate Solutions. Chemical Engineering Progress 1956, 52, (10), 433-438.
4. K.Yogish, Solubility of CO2 in Some Physical Solvents. Journal of Chemical Engineering of Japan 1991, 24, (1), 135-1137.
Presented Thursday 20, 13:30 to 14:40, in session EPIC-1: Poster Session (EPIC - Poster) - P2.
