Flash Drying of Polysilicon (Silica Microspheres)

Currently, crystalline silicon materials (including polycrystalline and monocrystalline silicon) are the primary photovoltaic materials, accounting for over 90% of the market share, and will remain the mainstream material for solar cells for a considerable period to come. For a long time, the production technology for polycrystalline silicon has been controlled by 10 factories operated by 7 companies in three countries—the United States, Japan, and Germany—creating a situation of technological barriers and market monopoly. The demand for polycrystalline silicon primarily comes from the semiconductor and solar cell industries.

A large-scale 10,000-ton flash dryer, manufactured by our company, recently underwent successful trial runs and commenced production at a factory in Fujian. This model utilizes an electric heating unit as the drying heat source, which is clean, allows for adjustable temperature ratios, and features automatic temperature control. The entire system has a small footprint, requires low capital investment, offers high production capacity, and features low energy consumption, integrating drying, dust collection, and packaging into a single unit. In the silicon materials market, the traditional process involved oven drying. However, due to the material’s extremely high bulk density (1.3 t/m³), the loading and unloading processes were labor-intensive, placing a heavy burden on workers. Additionally, the dried product generated significant dust, and the insoluble dust posed a serious health hazard to workers.

In this unit, the main machine is installed below ground level, positioning the feed inlet approximately 700 mm above the floor. Workers can easily load two to three bags of material (approximately 1.3 tons) per hour, significantly reducing labor intensity.

This machine integrates dust collection and packaging, featuring a dust recovery system for packaging. Material can be stored in a silo and discharged after cooling. The dust collection system is activated during packaging, resulting in minimal pollution of the workshop production environment.

Due to the high hardness of silicon materials, the entire crushing mechanism is chrome-plated. The successful development of this model marks the successful application of our company’s flash dryer technology for materials with high density and hardness. This machine is suitable for final processing stages in the silicon industry or similar sectors, offering a mature and advanced solution.