Applicability of anthracite filtration‒micro electrolysis‒sand filtration for the treatment of surface waters containing high turbidity

Resumo

The effect of combined filtration efficiency on the performance of anthracite filtration‒micro electrolysis‒sand filtration (AMS) was investigated. Impact of different operating parameters, such as iron‒carbon ratio of micro electrolytic units, filtration velocity of AMS, were studied. It was found that when iron‒carbon ratio was 6: 4, the AMS’s average turbidity removal rate was 96.75% at the filtration velocity of 3 m h^‒1. The results showed that when the filtration rate was 3‒9 m h^‒1 and iron‒carbon ratio was 6: 4, the turbidity removal efficiency was over 94%, and the turbidity of the effluent was less than 1 NTU in effective filtration cycle. The effective filtration cycle can last for more than 5 h or longer. Meanwhile, the removal rate of UV₂₅₄ was above 33%, and the concentration of iron ions in the effluent is less than 0.15 mg L^‒1. Turbidity and iron indicators have reached the national drinking water standards. It was also found the mechanism of iron‒carbon micro electrolytic enhanced filtration by infrared spectroscopy and scanning electron microscopy. And It was also speculated the reasons for the reaction passivation.