Allup Silica Limited (ASX: APS) has obtained premium specification results in its latest metallurgical tests based on improvements in the company’s process circuit design for the Sparkler Silica Exploration Project in Western Australia.
The results have produced a consistent high-grade <100 ppm Fe2O3 silica sands product from samples taken at Sparkler.
Grades of this purity are considered suitable for the photo-voltaic (solar panel) industry, which is a prime target market for Allup Silica.
Why is Achieving this Grade Important?
Silica sand is a raw material used in the production of optical fibre, ceramics, refractory materials and glassmaking, including the specialty glass required for photovoltaic (solar panels) and other high- tech product applications like tablet and mobile telephone glass.
The presence of impurities, particularly Fe2O3, has adverse effects on the silica sand product as it impairs transmission in optical fibres, reduces transparency of glass, discolours ceramic products and lowers the melting point of refractory materials. Silica sand, with these impurities, is also typically less valuable.
Results from the recently improved process circuit design include:
- Fe2O3 impurity lowered to an average of 84 ppm Fe2O3 (65 ppm to 110 ppm across four samples)
- SiO2 grades between 99.7% (lowest) and 99.8% (highest)
- An excellent 95%-97% recovery (yield) of SiO2 was achieved across all of the sighter tests, and this will be the focus of further optimisation work
The results from the improvements we are making to the process circuit are very encouraging and indicate that we do have the right projects and the high purity silica sands to start with,” Chairperson, Andrew Haythorpe, said.
“Being able to achieve the high purity specs required for the manufacture of PV cells means we are on track, and we look forward to being able to supply samples to potential customers as we progress to development on our Sparkler Project.”
Mr Haythorpre said results from the company’s work on its process circuit design is a positive step towards understanding how to produce a high purity silica sand that is suitable for use by the photovoltaic industry (specification >99.5% SiO2 and <100 ppm Fe2O3).
Testwork is ongoing to further refine the proposed process circuit methodology and achieve the ultimate goal of a consistent iron at sub-100 ppm across all of Allup Silica’s Exploration Projects.
The next work programme will serve multiple objectives:
- Producing a more consistent low impurity (<100 ppm Fe2O3) product
- Looking for potential to reduce capex and operating costs (reduction of upstream classifying)
- Enabling consistent Quality Assurance/Quality Control (QA/QC) production
- Achieving a methodology that could potentially support an increase in the depth of sand to be viably mined, as this may potentially increase estimated mineral reserves.
