Recovery from heavy oil reservoirs in Canada’s oil sands using primary production techniques is typically on the order of 5 to 10% of original oil in place.
Operators seeking to increase this recovery rate have considered a variety of enhanced oil recovery techniques such as water, polymer floods and even steam injection.
One of the key challenges is that the primary recovery process, usually referred to as Cold Heavy Oil Production with Sand (CHOPS), consists of producing vast quantities of sand throughout the well life.
Field and laboratory testing have shown that this massive sand production creates zones of high permeability which are often referred to as “wormholes” that may connect producing wells over distances greater than 100 m.
These high permeability zones left at the end of CHOPS operations makes it difficult to implement conventional enhanced oil recovery schemes such as water, polymer or steam floods due to “short circuiting” of the injected fluids along these pathways.
How We Help:
C-FER proposed a process to generate electricity by burning the oil in the reservoir following the CHOPS process.
Unlike traditional in situ combustion processes, the objective is not to recover the oil, but to burn as much of the oil as possible in situ, and capture the combustion products and steam to generate electricity on surface.
This requires a change in mindset in how to operate the combustion process; from attempting to create a narrow zone of combustion to generating a steam bank that pushes oil towards the producing wells, to how to create a broad area of combustion in the reservoir with efficient injection of oxidants and unimpaired production of the combustion products and steam.
Options were also considered for injecting oxidant during off-peak hours and generating electricity only during peak hours to maximize the economics of the process.