2015-Sustainable Industrial Processing Summit
SIPS 2015 Volume 3: Takano Intl. Symp. / Metals & Alloys Processing
| Editors: | Kongoli F, Noldin JH, Mourao MB, Tschiptschin AP, D'Abreu JC |
| Publisher: | Flogen Star OUTREACH |
| Publication Year: | 2015 |
| Pages: | 550 pages |
| ISBN: | 978-1-987820-26-3 |
| ISSN: | 2291-1227 (Metals and Materials Processing in a Clean Environment Series) |
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Challenges in Transporting the Off-Gases from the Silicon Process
Michal Ksiazek1; Ida Kero2; Bernd Wittgens1;1SINTEF, Trondheim, Norway; 2SINTEF MATERIALS & CHEMISTRY, Trondheim, Norway;
Type of Paper: Regular
Id Paper: 70
Topic: 3
Abstract:
The furnace process for silicon production is constantly improved both with respect to health, safety and environmental aspects and with respect to process and quality control. The notion of a closed furnace has often been discussed as it may provide several advantages, such as improved Si recovery, reduction of electrode consumption and carbon requirements. Additionally; it may enable more efficient recovery of the energy contained in the flue gas. Such improvement requires a safe and effective way of transporting the flue gas, which entails mitigation strategies for clogging and fouling by dust and SiO condensate. This, in turn, calls for increased understanding for the conditions and mechanisms for condensation of SiO-gas. The current paper gives an overview about the ongoing activities related to the transport of process gasses from a closed Si-furnace. Initially, small scale experiments are carried out, where the properties of SiO-gas is fundamentally investigated in terms of condensation temperature in different gaseous environments. SiO-gas was generated at 1650 A°C according to 2SiO2(s) + SiC(s) = 3SiO(g) + CO(g). Deposition of condensates started to take place at 1650 A°C. Condensates of different colors were deposited in the upper part of the reactor. The most common type was brown colored and was the product of the following reaction 2SiO(g ) = SiO2(s) + Si(s). Characterization of the condensates is performed by electron microscopy, chemical analysis and particle size distribution.
Keywords:
Combustion; Gas; Non-ferrous;References:
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