Treatment of high-salt wastewater generated during polysilicon production
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Dear colleagues, our company generates high-salt wastewater during the production process; some of this wastewater is sodium chloride-based, while another part is calcium chloride-based. Since it is produced as a result of the leaching of trichlorosilane, treating it is quite complicated. Is there any good way to deal with this?
Multi-effect evaporation. . . . In simple terms, it’s distillation. Help hold it up and see if there are any experts who will answer this.
Reply to 2# Hou Xiaodi: Thank you. This is a task that was suddenly assigned by the management. Since I am not very familiar with this area, nor do I know whether hydrolysis products of trichlorosilane could affect the efficiency of multi-effect evaporation, I would appreciate it if you could offer some guidance
I’m here too to learn about environmental protection*. However, our company does use multi-effect evaporation for desalination
First, neutralize the hydrochloric acid with NaOH or Ca(OH)2, then filter to remove the white foam (SiO2), and finally carry out multi-effect evaporation. The cost is high
It uses multi-effect evaporation technology, but crystallization easily occurs inside the pipes; it’s quite troublesome to operate in practice, and it also requires a significant amount of energy
Use MVR – no steam is needed; it’s too expensive. It only uses electricity, and no condensate water is required, which saves water resources and reduces coal pollution. Its energy consumption is extremely low, haha