Treatment of Reduced Wastewater after Vanadium Precipitation with Lean Slag from Ferrovanadium Smelting

In order to recycle lean slag from ferrovanadium(FeV50) smelting and treat wastewater from vanadium precipitation,lean slag with particle sizes smaller than 5 mm instead of lime powder was used after weathering and screening to neutralize the reduced wastewater with pH value of 7.0~8.5.The results indicate that 1 kg of chromium consumes 9.2 kg of lean slag ash,1.4 times of the amount of lime powder consumed.The total chromium,total vanadium,and suspended solids in the treated wastewater are less than 1.5 mg/L,1 mg/L,and 70 mg/L respectively,and its pH value is from 6 to 9,which means the treated wastewater satisfies the standard of GB26452 -2011.In a plant with an annual output of 2 000 tons of FeV50,more than 3 000 tons of waste slag generating in FeV50 smelting can be reduced each year.