Emerging producer Blue Energy (ASX: BLU) is advancing pilot well testing at the Sapphire Block (ATP 814) in Queensland’s onshore Bowen Basin.
All surface facility installations for the Sapphire 5 and Sapphire 6 pilot wells have been completed and both sets are now in the de-watering phase of the production testing program.
Early and sustained gas flow is being recorded and the company said it has been “very encouraged” by the results.
The flow of gas will be brought on in a measured manner to maximise long-term reservoir performance.
“Slow dewatering or depressurising of the coals is key to developing strong and increasing gas flow and will maximise the peak gas rate in due course,” it said.
Sapphire 5V production
Blue said the Sapphire 5V vertical water production well had been producing 265 barrels of water per day, which is being managed to slowly bring down the water level on each of the Sapphire 5L lateral coal seams.
The water level in Sapphire 5V is currently 80 metres above the shallowest coal seam intersection (Rangal seam) and 430m above the deepest (Moranbah seam).
Water production from the Sapphire 6V vertical water production well is currently at 183bbls of water per day.
“We are carefully regulating the dewatering process in Sapphire 5V and 6V to avoid any damage to the coal seams in the lateral wells, which can occur if water levels are drawn down too rapidly thereby reducing the pressure on the seams too quickly,” the company said.
“Even at this early stage of dewatering, the Sapphire 6 lateral pilot wells are producing a continuous gas flare, indicating that they are slightly ahead of the Sapphire 5 laterals on the de-pressuring curve.”
Average daily gas flow
Despite still being in the early days of testing, Blue said the average daily gas flow rate being measured from the Sapphire 6 lateral pilot sits at approximately 20 thousand cubic feet per day and is “very encouraging”.
“Gas flow has been evident from very early in the production test program at Sapphire pilot locations an encouraging sign,” it stated.
“We expect that with continued gradual dewatering, the gas rate will steadily increase as the pressure on the various coal seams in the pilot wells is gradually lowered.”
Blue will continue dewatering over the coming months with the intention of gradually increasing the gas rate.
