Flooding of oil-bearing strata - with oil in-water micellar solns. contg. increased amounts of petroleum sulphonates

摘要

Flooding soln. contains as dispersing agent, a petroleum sulphonate with monovalent cation and av. equiv. wt. 350-525 (400-475) in amt. of =5 times that required to give the critical micelle concn., together with water, hydrocarbon and opt. a co-surfactant and/or an electrolyte. Concn. of micelles is pref. =1x1020, esp. =2.5x1021 per litre. Pref. 1-50% of the pore vol. of the formation is injected, and is followed by an aq. soln. contg. a mobility-reducing agent e.g. a high-molecular electrolyte. Use of higher concns. of sulphonate gives increased displacement and recovery of oil from the formations.