Clay treating and oil-wetting dispersion and method of use thereof

Claim 2

The dispersion of claim 1 in which: said surface active salt is a salt of a N-alkyl-substituted polyamine and a petroleum sulfonate; and said preferentially water-soluble surfactant is an ethoxylated alcohol.

Claim 3

In a well treatment process in which a portion of the earth formation around a well is permeated with a fluid, the improvement which comprises: dispersing a preferentially oil-soluble, surface active polyamine salt of at least one anionic surfactant and at least one cationic surfactant in water containing at least one water-soluble electrolyte and at least one preferentially water-soluble ethoxylated alcohol surfactant; dispersing said surface active salt in said solution to an extent such that particles of the surface active salt are small enough to penetrate into the pores of a porous earth formation but are large enough so that the surface active salt is preferentially adsorbed on surfaces of an earth formation that is contacted by said dispersion; and permeating a portion of the earth formation around a well with said dispersion.

Claim 4

The process of claim 4 in which: said surface active salt is a N-alkyl-substituted polyamine; said preferentially water-soluble surfactant is an ethoxylated primary alcohol; and the earth formation into which the dispersion is injected contains oil in which naphthenic acids are present.

Claim 5

In a process for treating a well which has been complete into an interval of oil-containing earth formations that contains at least one zone of relatively high and one zone of relatively low permeability, the improvement which comprises: dispersing a preferentially oil-soluble surface active salt of at least one anionic surfactant and at least one cationic surfactant in an aqueous liquid solution that contains at least one water-soluble electrolyte and at least one preferentially water-soluble surfactant; establishing prEferential fluid-communication with the zone of said reservoir interval that has the relatively high permeability and injecting said dispersion with said surface active salt being dispersed to an extent such that its particles are relatively large but are small enough to penetrate into the pores of the earth formation; and establishing preferential fluid communication with the zone of said reservoir interval that has a relatively low permeability and injecting said dispersion with said surface active salt being dispersed to an extent such that its particles are relatively small and somewhat solubilized but are large enough to be preferentially adsorbed on surfaces of the earth formation.