Advanced Treatment of Secondary Sewage Effluent by Iron-Carbon Internal Electrolysis

摘要

Due to increasing water scarcity, appropriate technologies were need for advanced treatment of wastewater to enable reuse. Effect of iron-carbon internal electrolysis in tertiary treatment of wastewater was investigated in this study. Static experiment was adopted to evaluate influence of Fe/C ratio, pH, reaction time and aeration on pollutant removal by iron-carbon internal electrolysis. Then dynamic experiment was conducted to determine removal rate of CODcr, TP, chroma and NO3-N. The results showed that internal electrolysis could remove CODcr, TP and chroma efficiently. The optimal ratio of Fe/C was 1:1. Initial pH could affect removal efficiency. In acid circumstance, the removal rate was higher. Degradation reaction by internal electrolysis was fast, when the reaction time was lOmin, the removal rate could be ideal. In the process of internal electrolysis, aeration could increase pollutant removal rate. In aerated system, when the reaction time was only 15min, removal rate of CODcr, TP and chroma could reach 49.2%, 89% and 75%. But in non-aerated system, only when the reaction time was lOOmin could removal rate of these indexes reach 46.5%, 81% and 85.1%. In dynamic experiment, removal rate of CODcr, TP, chroma and NO3' could reach above 40%, 90%, 75% and 20%, respectively.