Talon Energy Ltd (ASX:TPD) and partner TMK Energy Ltd have passed another key milestone on the road to proving the commercial viability of the Gurvantes XXXV Coal Seam Gas (CSG) Project in the South Gobi Basin of Mongolia, confirming that the pilot well program has established continuous gas flows.
Project operator TMK has achieved critical desorption pressure in all three pilot wells, with gas flowing consistently from all wells.
The permanent gas flow has been achieved at the Lucky Fox-1, Lucky Fox-2 and Lucky Fox-3 wells, with each flowing sufficient gas to support continuous flares.
All three wells still have a significant hydrostatic head that is being continually pumped off in accordance with the reservoir management plan.
Talon said it was likely to take several more weeks before the hydrostatic head was reduced to the optimal level, after which it expected to be able to report initial flow rates from each of the wells.
Pump speeds increasing
Since commissioning of the wells around three weeks ago, all three have been continuously on pump, with pump speeds gradually increasing to slowly reduce the fluid levels in the wells and the reservoir’s hydrostatic pressure.
Currently, the wells are producing around 600 barrels of water per day, combined, yet fluid levels continue to slowly decrease. As pump speeds are increased over the coming weeks, and as the fluid levels decrease, the reservoir will continue to depressurise.
Now that critical desorption pressure has been reached in each of the three wells, the current low gas rates are expected to gradually increase as is typical of CSG wells.
Once the optimal fluid levels are achieved in each of the wells, pump speeds will be managed such that the hydrostatic head will be kept at a constant level and at that point, an initial gas rate is expected to be able to be reported.
That initial gas rate is then forecast to increase over the six months of the extended production test as the pressure sink continues to expand from the immediate surrounds of the well bore further into the coal seams, thereby freeing up more gas to flow into the wellbore.
While the initial results are highly encouraging, to assess the commercial significance of the extended production test, gas flows must be measured over the test’s full duration of the test. This is needed to have enough data to model the deliverability of the wells and a potential production profile.
Exceeding expectations
Talon managing director and chief executive officer Colby Hauser said: “With the continuous flow of gas from the three Lucky Fox pilot production wells, we are very pleased to see that the Gurvantes XXXV Coal Seam Gas Project has now passed another key milestone on the road to proving it’s commerciality.
“The pilot production well program continues to exceed our expectations and we are looking forward to providing the market an update on the initial flow rate from this exciting project in several weeks’ time.
"We extend our thanks to our partner in this project, TMK Energy for the excellent project management thus far.”
Talon is a 33% owner of the Mongolian CSG project, with project operator TMK Energy holding 67%.
- by Meagan Evans