Patents by Inventor Luiz Cesar Ferreira Barbosa

Luiz Cesar Ferreira Barbosa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Process for the reduction of the relative permeability to water in oil-bearing formations
    Patent number: 6474413
    Abstract: A process for the selective and controlled reduction of permeability to water in oil-bearing formations made up of sandstone or limestone, the process comprising the injection of a slug of polymer aqueous solutions having a polarity opposite to the polarity of the rock, followed by the injection of a spacing slug of alkaline halide and then a fresh slug of polymer aqueous solution, the polarity of which is opposite to the polarity of the first polymer slug, and then a slug of aqueous solution of trivalent metal crosslinking agent to effect the partial crosslinking of the polymer charges, the polymer layers being successively added until the injection pressure of the polymer aqueous solutions show that the desired Residual Resistance Factor RRF was attained, and well production may be resumed.
    Type: Grant
    Filed: September 21, 2000
    Date of Patent: November 5, 2002
    Assignee: Petroleo Brasileiro S.A. Petrobras
    Inventors: Luiz Cesar Ferreira Barbosa, Sérgio Luiz Pereira De Freitas Coelho, Carlos Roberto Carvalho De Holleben, Geraldo Maria Ramos De Godoy