In situ RF heating of stacked pay zones

摘要

A method of heating stacked pay zones in a hydrocarbon formation by radio frequency electromagnetic waves is provided. In particular, radio frequency antenna array having multiple antenna elements are provided inside a hydrocarbon formation that has steam-impermeable structure. The antenna elements are so positioned and configured that the hydrocarbons in the place where conventional thermal methods cannot be used to heat due to the steam-impermeable structure can now be heated by radio frequency electromagnetic waves.

主权项

1. A method of enhancing production of hydrocarbons in a hydrocarbon formation beneath an overburden and having a plurality of stacked pay zones separated by a plurality of steam-impermeable structures, comprising:
a) providing producer wells within the hydrocarbon formation; b) measuring electric conductivity in the stacked pay zones and the steam-impermeable structures to determine areas having the highest electric conductivity; c) providing a radio frequency (RF) antenna array within the hydrocarbon formation at said areas having the highest electric conductivity, wherein the RF antenna array having a plurality of antenna elements is connected to an alternating electrical current source oscillating at radio frequencies and wherein adjacent antennas in said RF antenna array are staggered, and wherein said antenna elements are linear dipole elements; d) generating a time varying electromagnetic field at said antennas, so as to create eddy currents in the stacked pay zones and heat at least a portion of the hydrocarbons predominantly by joule heating; and e) producing the hydrocarbons through the producer wells, wherein the connection between the RF antenna array and the alternating electrical current source is shielded to avoid undesired heating at the overburden.