I am doing a project looking into the advantages of radio/microwave heating of oil reservoirs. I've seen research indicating that RF/Microwave heating can be used for environments such as shallow, tight, high permeability, fractured, etc zones. What are the disadvantages of applying techniques such as SAGD in these zones?
1 Answer
Heating oil makes it less viscous which makes it easier to flow and thus easier to pump. RF/microwave heating is an easy and relatively safe way of reducing the viscosity of the oil a reservoir.
Additionally, the greater the permeability of a rock mass the more easily a fluid will flow through it. If a rock mass has large pore spaces, such as sandstone, the more permeable it will be. For rock which has small/tight pore spaces the permeability can be increased by fracturing the rock mass.
SAGD (steam assisted gravity drainage) is another way to reduce the viscosity of the oil. The effectiveness of SAGD would rely on how precise the horizontal steam holes were drilled relative to each other.
Rock mass have varying properties and there may be softer and harder portions within a rock mass. This can affect the path of the drill bit and steel when the holes are drilled. Consequently, the holes may not always be exactly where they are required for efficient SAGD recovery of the oil. Some parts of the reservoir may be cooler or hotter than needed. Applying additional heat via RF/microwave heating will increase the likelihood of more of the oil being heated and having its viscosity reduced and thus potentially increasing the recovery of oil from the reservoir.