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:
Oct. 15, 1991
Filed:
Apr. 16, 1990
Patrick J Breen, Houston, TX (US);
Hartley H Downs, Kingwood, TX (US);
Bruce N Diel, Willowbrook, IL (US);
Baker Hughes Incorporated, Houston, TX (US);
Abstract
Complex molecules of phosphonic acid ligands and transition metal ions are formed to be surprisingly good at inhibiting and even preventing scale in aqueous solutions, crude oils, aqueous production fluids, heat exchange media, etc. Ethylenediaminetetra(methylenephosphonic) acid (ENTMP) complexed with copper (II) is a particularly effective scale inhibitor over wide pH and temperature ranges. Other useful metal complex molecules include various alkyleneamino(alkylphosphonic) acids, or salts thereof, complexed with transition metals such as nickel (II), cobalt (II) and zinc (II), in addition to copper (II). The active complexes may be termed phosphonate metal complexes, or in some forms, phosphonic acid metal complexes.