The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 21, 1999
Filed:
Dec. 19, 1997
Celso Rodrigo De Souza, Rio de Janeiro, BR;
Carlos Nagib Khalil, Rio de Janeiro, BR;
Petroleo Brasileiro S.A. - Petrobras, Rio de Janeiro, BR;
Abstract
An improved method is provided for the thermo-chemical dewaxing a large dimension line or conduit using a Nitrogen Generation System/Emulsion. The method involves introducing an emulsion into the conduit to be waxed. The emulsion comprises an internal aqueous phase and an external organic phase. The aqueous phase comprises an oxidizing nitrogen salt, a reducing nitrogen salt and water. The organic phase comprises a non-polar organic liquid, such as kerosene, and a delayed action activator for inducing the reaction of said oxidizing nitrogen salt and said reducing nitrogen salt. The improvement comprises a delayed action activator which may be a copolyanhydride such as poly(adipic-co-sebacic)anhydride solubilized in a polar organic solvent such as chloroform. The solubilized delayed action activator is easily and accurately pumped into the conduit to be dewaxed. The emulsion is maintained in the conduit until the delayed action activator induces the reaction of the nitrogen salts to generate nitrogen and heat, thereby fluidizing wax in the conduit.