PUREVAP(TM) PROCESS TRANSFORMS LOW PURITY QUARTZ (97.5%) TO HIGH PURITY SILICON METAL POWDER
PyroGenesis Canada Inc.'s (PYR.V) Purevap process can not only transform high-purity quartz to high-purity silicon metal, but the process can also transform low-purity quartz (97.5 per cent) to high-purity silicon metal.
"These results are significant as the prevailing proposition suggests that the quartz purity level required to make high-purity silicon metal is over 99.5 per cent (1)," said P. Peter Pascali, president and chief executive officer of PyroGenesis. "The Purevap has proven that to no longer be the case. We have demonstrated that the process can produce quartz of a significantly lower purity level (97.5 per cent) as feedstock, and still produce high-purity silicon metal. The implications of this are enormous when considering the potential commercial applications of the process. Conceivably, we can now take a cheap and abundant low-purity quartz feedstock and transform it into a high-value end product."
"We are extremely pleased with the progress to date," said Pierre Carabin, chief technology officer of PyroGenesis. "Particularly, when one considers today's results in light of our press release dated Sept. 29, 2016, wherein we announced, amongst other things, that the Purevap process can remove one of the toughest impurities on the road to solar-grade silicon, namely boron, from the final material produced. It seems that we are truly on to something unique."
In addition, Mr. Pascali provides a background/update in the following question and answer format.
What is the Purevap process?
The Purevap process is a process being developed by PyroGenesis which is targeting the transformation of quartz, in one step, into a solar-grade metal suitable for solar panel applications. This effectively eliminates significant overheads thereby creating a simple, pure and cheap alternative to that currently available. If successful, this process could have a significant impact on the solar panel industry. Of note, however, there are significant additional commercial applications at lower silicon purity levels as reflected in the attached table (2).
Categories of silicon Silicon purity Applications Metallurgical-grade Casting and chemical industry silicon (MG-Si) approx. 98-99.5% (for example, silicones) Chemical-grade polysilicon 3N-5N Chemical industry Solar-grade polysilicon Photovoltaic industry, solar (SOG-Si) 6N-9N industry Semiconductor industry Electronic-grade (for example microchips in computers, polysilicon 9N-11N tablets and cellphones)
What is PyroGenesis currently contracted for with HPQ Silicon Resources Inc.?
As previously disclosed, PyroGenesis was first engaged by HPQ in February, 2015, to demonstrate, on a laboratory scale, that the Purevap process could produce high-purity silicon metal from quartz in just one step. It was based on the successful results of this testing that an $8.3-million contract was signed with HPQ to design, fabricate, assemble, commission and test a 200-metric-tonne-per-year Purevap pilot system to produce silicon metal directly from quartz.
PyroGenesis is also engaged by HPQ in a second testing phase (phase 2), geared toward generating and collecting data which can be used for the scale-up of the Purevap process. It is within this phase 2 testing that the current results were demonstrated.
What has recently been demonstrated?
As mentioned, the goal of the phase 2 was to collect data for the design of the Purevap pilot system. In so doing, the company decided to test the limits of the system by introducing low-quality quartz as feedstock (97.5 per cent). The results are compelling as they demonstrate that the Purevap system can produce a high-quality silicon metal from a low-purity feedstock.
Can you briefly explain the difference between the Purevap process, the conventional processes used and any that may have recently failed at trying to process solar-grade silicon from quartz?
Of course. In the conventional process, an electric arc furnace is used to transform the quartz into metallurgical-grade silicon (MGS), which is then dissolved in hydrochloric acid and then, after several additional steps, solar-grade silicon is formed. Separately, the now-defunct Timminco Ltd. attempted to replace the hydrochloric acid step with a rotary furnace and thereby, in theory, form solar-grade silicon without the additional steps required in the conventional process. The significant difference between both these processes and the Purevap process is that the Purevap process starts directly with quartz which is introduced into a vacuum arc furnace with no additional steps required. The Purevap process does not have to create a MGS; it is all done in one step, creating significant advantages.
(1) NI 43-101 preliminary economic assessment on the Langis silica deposit and a metallurgical silicon processing plant in the Matapedia region, province of Quebec, Canada. PEA study prepared by Viridis.iQ GmbH in accordance with the requirements of National Instrument 43-101; "Exploring for silica in Quebec," SIDEX, on-line report, February, 2015, accessed on Nov. 1, 2016.
(2) J.O. Odden, G. Halvorsen, H. Rong, R. Glockner, comparison of the energy consumption in different production processes for solar-grade silicon, conference: Silicon for the Chemical and Solar Industry IX, Oslo, Norway, June 23 to 26, 2008; "Value chain activity: producing polysilicon," Green Rhino Energy, accessed on Nov. 1, 2016.