Abstract: Solvent compositions for dissolution of both asphaltene and paraffin petroleum based deposits are described. Solvent compositions comprising kerosene and alkyl phenols, preferably cresol, have been found most efficient in oil well cleaning applications. This efficiency can be enhanced by the addition of an alkylamine. Compositions containing other aliphatic hydrocarbon solvents and more than 3% by volume alkyl phenols also exhibit good solvent properties for petroleum deposits. Oil production can be enhanced following well treatment in accordance with the disclosed invention.

Abstract: Method and apparatus for separating water and crude oil mixtures and other two-phase fluid mixtures of components of different densities. The mixture is pumped through a conduit in the form of a vertical spiral at a velocity that impels the heavy phase toward the outside of the spiral. A fraction is withdrawn from the outside of the turns of the spiral and is led downwardly to the bottom of a vertical settling tank. Any light phase removed with the heavy phase floats to the top in the settling tank and is reintroduced at the top of the spiral.