Single-well SAGD

In our Forum section on heavy oil recovery methods, one of our readers asked about a recovery method known as single-well SAGD (SW-SAGD). In a typical SAGD approach, steam is injected into a horizontal well located directly above a horizontal producer helping to displace heated oil. SW-SAGD alternatively attempts to create a similar process using only one horizontal well. In the process, high quality steam is injected through coiled tubing into the toe of the well. The steam condensate and reservoir fluids flow to the heel to be produced. The obvious advantage with SW-SAGD is the reduced drilling and completion costs of the second well. Typically SW-SAGD is preceded by cyclic steam stimulation (CSS) to heat the near wellbore area to create conditions that improve initial SW-SAGD response.

As there are many variables in SAGD operations, the best approach to optimize recovery is to carefully plan and simulate multiple SAGD strategies including SW-SAGD for your particular heavy oil reservoir. SPE 50412-MS, Numerical Investigation of SAGD Process Using a Single Horizontal Well, is a good reference on the subject.

Kambiz.