Patent Yard Sign in
Expired Canadian patentCanada

Method of restoring permeability around wellbores

CA 1297784 C · Owner: Texaco Development Corporation · Inventors: Brost, Dale F.

CIPO record

Overview

Drawings and full text

Its claims, description and drawings are in the Canadian Patents Database.

Open the CIPO record

Abstract From the Canadian patent

METHOD OF RESTORING PERMEABILITY AROUND WELLBORES (D#78,894-F), ABSTRACT OF THE DISCLOSURE The invention is a method of restoring the permeability of an underground hydrocarbon formation adjacent to a wellbore which comprises injecting a first aqueous solution of hydrochloric or hydrofluoric acid into a formation interval where permeability has decreased due to polymer plugging and producing that acid out of the well after a soaking period. A second solution of about 200 ppm to about 2% by weight of chlorine dioxide is injected into the same interval and followed by a third solution of hydrochloric or hydrofluoric acid. The second and third solutions are allowed to soak in the formation for …

Read the whole patent

Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.

Why it's free to use

  • Granted March 24, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended March 24, 2009.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledMay 23, 1989
GrantedMarch 24, 1992
Term endedMarch 24, 2009
Patent numberCA 1297784 C
Classification (IPC)C09K3/00 +2 more

Timeline

Timeline From CIPO dates

1990199219941996199820002002200420062008Application filedMay 23, 1989Patent grantedMarch 24, 1992Term endedMarch 24, 2009

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.