A unique photovoltaic-grade polysilicon feedstock made from siliceous sludge
Thread Content
On the evening of January 28, Tongde Chemical announced that since its establishment, the Tongde Research Institute, with Dr. Liu Lixin’s technical team as its core, has been working on the industrialization of purification technologies using the siliceous sludge metallurgy method. Using Shanxi Rocky Mountain Photovoltaic Energy Technology Co., Ltd., located in Changzhi City, Shanxi Province, as a testing base, after more than a year of effort, it has successfully developed a unique photovoltaic-grade polycrystalline silicon material made from siliceous sludge. This technology fills a gap both domestically and internationally. At present, the production, testing, and final product inspection of the polysilicon raw material project have achieved performance levels comparable to those of similar products in the existing market. Moreover, after single-crystal pulling tests, it meets all the technical requirements for materials used in photovoltaic solar applications.
In 2016, the price of crude polysilicon dropped below 85 yuan per kilogram; as one problem affected others, domestic polysilicon manufacturers that used the metallurgical process, with Xiamen Jiake being a representative example, were forced to close down. Research on the production of polycrystalline silicon via metallurgical methods has come to a standstill. Surprisingly, in 2017, Elkem’s metallurgical polysilicon made a comeback, with costs that were far lower than anyone had imagined, and its quality was also exceptionally good. With the market price of virgin polysilicon at 150 yuan per kilogram, Elkem’s 6N metallurgical-grade polysilicon is available for only 6 dollars per kilogram. Moreover, PERC cells made using Elkem’s metallurgical-grade polysilicon exhibit lower degradation rates compared to those made with virgin polysilicon. REC is a subsidiary of Elkem (Elkem was acquired by China’s Lanxess Group in 2011 for $2 billion; therefore, REC in Norway is a state-owned enterprise!) ), due to the relatively limited production of polysilicon via Elkem’s metallurgical method, it is sold only to REC. This is the main reason why REC in Singapore is able to thrive in a country where labor and utility costs are so high. It is said that Elkem’s production process for 6N polysilicon using the metallurgical method involves using silicon sludge cut with diamond wires as raw material, and employing metallurgical processes to produce 6N polysilicon in the end. If this production process can be used to manufacture 6N polysilicon, it will not only **alleviate the current shortage of polysilicon** but also **reduce the production costs of polysilicon wafers**. Currently, the price of native polysilicon remains strong; it’s unclear how long this strength will last.
This news is quite explosive, just like the production of particle-shaped solar-grade polycrystalline silicon using the fluidized bed method. A real technological breakthrough could revolutionize this industry.
That is, it brings down the price of polysilicon to rock-bottom levels in no time