Patent · US Expired

Mineral well heating systems

US4790375A · kind A · utility

85Cited by
7References
56Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 23, 1987
Grant dateDec 13, 1988
Priority date
Expiry dateNov 23, 2007

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S166/902
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

Heating systems for mineral wells (e.g. oil wells) employ electrical power sources, sometimes operating at relatively high frequencies, that are connected to the well casing and production tubing so as to provide a coaxial line electrical heater projecting down into the well. The heating pattern of the coaxial line is effectively controlled so that most of the power is dissipated as heat, primarily in the tubing, above a depth D above which paraffins or other condensible constituents would tend to condense or otherwise impair the flow of mineral fluid up through the production tubing. The applied electrical power is controlled so that the fluid is kept approximately at or only somewhat above the flow impairment temperature for constituents of the fluid. In some embodiments the system is extended to provide heating of a portion of the deposit formation adjacent to the well.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.