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Initial planned production
Viridis.iQis planning to build and operate an initial recycling production factory for
the recycling of kerf and grinding fines wastes. This factory will be designed to handle
both waste streams to maximize cost benefits and to capitalize on availability of waste
streams. The initial location of the factory is planned in Europe at the existing site of an
operating partner in order to reduce CAPEX and infrastructure costs and to utilize
existing procurement channels. Currently
Viridis.iQis raising capital for the project
with a planned start up in 2017 and a capacity of 3000 tons per year of metallurgical
silicon powder meeting the specifications of polysilicon and chemical customers.
Conclusion
The photovoltaic market continues to grow and is expected to reach 80 GW of
installed capacity per year by 2020, which represents a growing dependency on the
metallurgical silicon for which it uses as a feedstock. The solar industry value chain
currently loses nearly 200 000 ton of usable silicon per year due to process restrictions
that force this material to drop out of the sector. This lost potential of silicon represents
nearly 45 GW of annual power production, which is more than the accumulated
installed solar capacity of Germany.
The recycling of waste silicon is not a new development and many efforts have been
tried but mainly based on using the wastes from kerf as a substitute for polysilicon. The
authors have developed a different approach that instead considers the wastes as a
substitute for metallurgical silicon feedstock and not polysilicon. This approach is more
industrially and economically viable and technically possible with the development of
the process done by
Viridis.iQ.The process steps developed include a wet chemical, thermal treatment and gas
atomization step; the latter of which brings added benefits to the material via superior
homogeneous physical properties and the ability to add specialized catalysts to improve
reactivity in polysilicon production.
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