Patent ID: 6353706
Filing Date: 2002-03-05
Classification: E21B

Abstract:
An electrical heating method for mineral wells, comprising a bore hole, a well casing, a metallic fluid admission section located adjacent a hydrocarbonaceous-reservoir of a heterogeneous reservoir that has at least two longitudinally spaced producing intervals that have different thermal heat transfer characteristics, comprising the steps of:providing a downhole electrically energized heater having at least two independently controlled heating elements spaced apart longitudinally from each other, positioning at least one of said heating elements near a first of said producing intervals adjacent said fluid admission section, positioning a second of said heating elements near a second of said producing intervals adjacent said fluid admission section, supplying electrical energy to each of said heating elements to increase the temperature of the producing interval near each of said heating elements, measuring the temperature adjacent each of said heating elements, and controlling the quantity of electrical power supplied to each of said heating elements in accordance with the thermal transfer characteristic of each of said producing intervals to realize a specified temperature near each of said heating elements.