Study on Waste Residue Resource Utilization of Polyaluminum Chloride Prepared from Fly Ash
In order to improve the comprehensive utilization of fly ash,using polyaluminum chloride residue with different compositions as raw material,silica fertilizer were prepared by roasting,and the effect of the main components in raw materials on the effective silicon content of silicon fertilizers was studied.The results showed that it is feasible to prepare silicon fertilizer using waste residue of polyaluminum chloride from fly ash.The effective silicon content of silicon fertilizer prepared from polyaluminum chloride residue with different SiO2 content was similar,which could reach about 30%.The main phases of silicon fertilizer were CaSiO3 and NaAlSiO4,and a small amount of Ca2Al2SiO7 could be formed when the content of Al2O3 in the residue was high.The content of arsenic,cadmium,lead,chromium and mercury in silicon fertilizer were much lower than GB 38400-2019 standard limit,which met the ecological index.