Application of shear induced structure materials for brine flooding in sandstone oil reservoirs

Shear induced structure (SIS) chemicals need to be used at higher concentrations in brines than with water to obtain the same effect for retardation in higher permeability reservoir rock. A threshold level of between 1 and 2 mM SIS concentration is sufficient to overcome typical salt concentrations (ca. 3%) found in brines. The flow retardation occurs over injection volumes greater than one pore volume suggesting permeability dependent proppant formation. The micellar component is selectively absorbed in porous sandstones (Berea and Bentheim). However the cosolute is only absorbed in the presence of the micellar component. Analysis of the solution viscosities indicates the existence of an extra component of resistance during permeable flow within the sandstone cores. This is attributed to elongational effects. Prior to application, it is necessary to know how much SIS chemical is lost from the aqueous to the organic phase. during the two phase flow associated with water flooding to displace oil. Comparison of contact component transfer shows that more SIS components are lost from the aqueous phase on contact with higher aromatic oils.