There are more than 60 kerogen processing technologies, but many are at little more than experimental stage. After determining which of the technologies were at a more advanced development stage, QER undertook a thorough review and investigation of many of the technologies that have proven performance. Primary amongst these proven technologies is the vertical shaft retort Paraho technology, developed in Colorado, USA, during the late 1970s/early 1980s.
QER, in association with the technology owners, recommissioned the Paraho pilot plant facility in Colorado during 2005 to test representative samples of Queensland oil shales utilising the Paraho process.
QER set key criteria to determine the suitability of the technology for further development. Broadly these criteria included:
- Environmental (emissions) performance
- Retort performance (throughput rate and yield)
- Process stability
- Process controllability
- Process predictability
On all counts, the trials were successful. The Paraho process has proven to be robust, reliable, responsive and controllable. The main distinguishing characteristics of the Paraho process have proven to be:
- High Availability - Mechanical simplicity translates into minimal downtimes and high availability.
- High Oil Yields - Operationally flexible allowing for steady retorting operations and consistent, high oil yields.
- Energy Efficient - High thermal efficiency allows for better capture and reuse of generated process heat, resulting in overall lower operating costs.
- Safe To Operate - Low pressure, thermally encapsulated process with few moving components is safe to operate.
- Environmental Performance - Thermal extraction process generates waste streams typical of other thermal processes and those waste streams can be managed using comparable control technologies.
QER used the data gathered from the Paraho pilot program to enable the successful design and commissioning of a Paraho technology demonstration facility in Gladstone, Queensland.
The Paraho pilot plant near Rifle, in Colorado (left) and The Paraho II technology demonstration plant in Gladstone, Queensland.