(Repost) Bottleneck in the utilization of polysilicon by-products resolved

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The bottleneck in the utilization of polysilicon by-products has been overcome. On February 24, reporters learned from the China Fluorosilicon Organic Materials Industry Association that extending the polysilicon industry chain into the silicone sector and using its by-product, silicon tetrachloride, as a raw material for producing silicone products can not only solve the long-standing problem of dealing with these by-products for polysilicon manufacturers but also enable the production of silicone products with high added value. This circular economy model has overcome the bottleneck in the utilization of polysilicon by-products. Yue Rundong, honorary president of the China Fluorosilicon Organic Materials Industry Association and a professor-level senior engineer, told reporters that the key factor affecting the development of the polysilicon industry is the utilization of its by-products. Silicon tetrachloride is the main by-product in the production of polysilicon; 8–10 tons of liquid silicon tetrachloride are produced as a by-product for every ton of polysilicon manufactured. According to rough estimates, the polysilicon production capacity that can be achieved in the near future from projects that have already been completed or are currently under construction amounts to nearly 90,000 tons. If the polysilicon production reaches 90,000 tons, the by-product silicon tetrachloride will amount to nearly 800,000 tons. Due to its strong corrosiveness, the difficulty in storing and transporting it, and its tendency to volatilize, which is harmful to the environment, polysilicon has also been labeled as highly polluting. Although polysilicon is a fundamental material based on the clean energy source of solar power, silicon tetrachloride generated during its production can become a bottleneck restricting the development of the polysilicon industry if it is not utilized comprehensively. Yue Rundong explained that the current approach to addressing the environmental issues associated with polysilicon in China is to use the by-product silicon tetrachloride as a raw material, thereby extending the polysilicon production chain towards silicone products. One of these methods involves converting silicon tetrachloride into fumed silica. For example, the 20,000-ton-per-year phase I project, consisting of two units each with a capacity of 800 tons per year, for fumed silica production by Leshan Jibisheng Silicon Materials Company was successfully commissioned in November 2008 in Leshan City, Sichuan Province. This is a technology developed in China that possesses complete independent intellectual property rights. Another approach is to convert silicon tetrachloride into products such as silicone monomers or silane coupling agents; research and development in this area are also being carried out abroad. The market demand for silicone products in our country is on the rise, and the market potential is considerable. In previous years, the growth rate was 30%, and it continues to grow at a rate of 15% to 20% at present. Even in the current economic downturn, the prospects remain positive. Currently, there are already pilot or pilot-scale technologies available in China in this area, and efforts are being made to gradually move towards industrialization. Therefore, the association calls for **support in formulating projects for these technologies to further accelerate their industrialization process. Compared to traditional silicon solar cells, these new solar cells based on polymeric plastics are cheaper and easier to manufacture, thus offering broader market prospects. (China Chemical Industry News)