摘要 |
Polycrystalline silicon in the form of chunks packed in plastic bags containing a mass of at least 5 kg, including chunks of size from 20 to 200 mm, wherein any fines fraction in the plastic bag is less than 900 ppmw, preferably less than 300 ppmw, more preferably less than 10 ppmw. The polycrystalline silicon, after comminution of a silicon rod obtained by CVD (Siemens process), is sorted and classified, optionally dedusted and then metered and packed. Metering and packing units include elements for removing fines or small particles during metering and during packing. The packing unit includes an energy absorber or a reservoir vessel which enables sliding or slipping of the silicon chunks into the plastic bag. Gas flow generated within the plastic bag after the bag has been filled transports the dust or small particles out of the bag, and these are sucked out with a suction device.
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