Patents by Inventor Tawfiq A. Al-Shafai

Tawfiq A. Al-Shafai 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).

  • Method and composition for forming protective precipitate on cement surfaces prior to formation acidizing treatment
    Patent number: 7328746
    Abstract: A method and composition for protecting cement surfaces in a well bore treatment zone from the destructive effects of acid mud and other acidization processes commonly used to stimulate hydrocarbon production from the formation, includes contacting the cement with an aqueous acid mixture of HAc and HF in a mutual solvent for a sufficient period of time to form a protective deposit or precipitate layer that is resistant to the acidization composition. In a preferred embodiment, the aqueous acid mixture includes corrosion inhibitors and inhibitor aids, and a preflush with an ammonium chloride solution in a mutual solvent is used to prepare the cement surfaces in the treatment zone.
    Type: Grant
    Filed: March 1, 2005
    Date of Patent: February 12, 2008
    Assignee: Saudi Arabian Oil Company
    Inventors: Ali A. Al-Taq, Hisham A. Nasr-El-Din, Tawfiq A. Al-Shafai
  • Method and composition for forming protective precipitate on cement surfaces prior to formation acidizing treatment
    Publication number: 20060196666
    Abstract: A method and composition for protecting cement surfaces in a well bore treatment zone from the destructive effects of acid mud and other acidization processes commonly used to stimulate hydrocarbon production from the formation, includes contacting the cement with an aqueous acid mixture of HAc and HF in a mutual solvent for a sufficient period of time to form a protective deposit or precipitate layer that is resistant to the acidization composition. In a preferred embodiment, the aqueous acid mixture includes corrosion inhibitors and inhibitor aids, and a preflush with an ammonium chloride solution in a mutual solvent is used to prepare the cement surfaces in the treatment zone.
    Type: Application
    Filed: March 1, 2005
    Publication date: September 7, 2006
    Inventors: Ali Al-Taq, Hisham Nasr-El-Din, Tawfiq Al-Shafai