Multi-stage hydraulic fracturing and radio-frequency electromagnetic radiation for heavy-oil production

•A set of equations were solved for a well with two perpendicular fractures under RF EM heating.•A correction approach was presented for more accurate estimation of heat distribution around the well.•Multi-stage RF-EM treatment is most effective in the case of “short” fractures with low conductivity.•In field conditions, the process can be started as “cold” production after hydraulic fracturing.•Periodically switching the generator on and off will reduce the risk of undesirable high temperatures.

Numerical model results of heavy oil production through multi-stage radio-frequency electromagnetic (RF EM) heating from a well after fracturing and re-fracturing operations are given in this paper. We consider the inflow of heavy oil to the well through two perpendicular fractures filled with propping agent. The conductivity of fractures is substantially greater than the conductivity of the reservoir but the dielectric and thermal properties of the reservoir and fractures are considered identical. In the expression used for heat distribution, a correction for near-field is introduced, which is shown to improve the accuracy of the temperature distribution around the well. The calculations for different powers of EM emitters and length of fractures are also considered and compared to the base case (cold oil) production.