Supplement to SPE 19505, The Steam-Foam Process–Review of Steam-Foam Process Mechanisms
Author: G.J. Hirasaki (Shell Development Co.)
Surfactants reduce the steam mobility by stabilizing the liquid lamellae that cause some or all of the steam to exist as a discontinuous phase. The propagation of surfactant is retarded by adsorption. In the phase. The propagation of surfactant is retarded by adsorption. In the case of ion exchange of divalent ions from the clays, the surfactant is also retarded by precipitation and/or partitioning into the oil. The rate of propagation of foam is also determined by the mechanisms that generate and destroy foam. The generation mechanisms include: (1) leave-behind, (2) snap-off, and (3) division. The destruction mechanisms include: (1) condensation and evaporation, (2) coalescence by a limiting capillary pressure, and (3) coalescence due to the presence of oil. The foam texture can be predicted from a population balance which includes these mechanisms.