Polysilicon
TCS-Based Siemens Reactor Process
During the process, raw material, intermediate products and byproducts include Si powder, cl2, H2, Hcl, SiHcl3, SiH2cl2 and Sicl4, therefore valve’s design must be able to deal with these medium, especially the highly abrasive Si powder.
the chemical compounds are extremely danger-ous. H2 and SiHcl3 are easily combustible, Hcl is dangerous and extremely corrosive, SiHcl4 is a highly toxic substance that poses environmen-tal hazards, which makes it necessary to recover these substances, and bring them back into the production process. Handling these chemicals, including the safe and environmentally sound disposal as well as emission control at the same time is not easy. All these chemicals should be captured and recovered to decrease raw mate-rial consumption and increase the whole process efficiency.
SiHcl3 production is a complex reaction equilib-rium system, different products and by-products form in the fluid bed reacto. reaction condi-tion should be controlled precisely to maximize SiHcl3 yield.
Silane-Based Fluidized Bed Reactor (FBR) Process
In an FBR, monosilane is injected through nozzles at the bottom to form a fluidized bed that carries silicon seed particles fed from above. Silicon deposits on the seed particles until they have grown to larger granules, which can then be withdrawn from the reactor continuously.
TYPICAL APPLICATIONS
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Silicon Powder Feed
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Silicon Fine High Cycle Valve
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Reactor Exhaust
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Reducing furnace isolating valve
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By-products recycling valve
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Anhydrous Hydrogen Chloride
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Hot Oil Supply
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Chlorosilane Vapor
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Vents with Hydrogen
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Sodium Valve