不同人工湿地基质对污水总有机碳去除能力初探

选择4种常见基质及基质配比,研究其碳含量和组分对污水中总有机碳(TOC)的去除影响。结果显示当污水的TOC浓度为27 mg/L时,4种基质都向水体中释放碳,且释放碳的大小顺序为:砂子-土壤-泥炭混合基质土壤砂子-土壤混合基质砂子,基质的碳含量越高,释放到水体中碳越多。3种基质对水体中TOC的去除率大小顺序为:土壤砂子-土壤混合物基质砂子,基质碳含量越高,微生物活性越强,对TOC的去除率越高。在第12天,砂子-土壤-泥炭混合基质处理中TOC浓度的增加,与其稳结合态有机碳含量较高有关。有机碳含量和组分影响了人工湿地基质对TOC的去除。

Preliminary investigation on effect of different constructed wetland substrates on capacity of removal of TOC in wastewater

The effect of quantity and components of carbon in substrates on the removal rate of TOC in wastewater was investigated by four substrates or ratio to different substrates. Results showed that carbon was released from four substrates, and the quantity of the released carbon was different following the order of mixture of sand, soil and peat > soil > mixture of soil and sand > sand, when concentration of total organic carbon (TOC) in wastewater was 27 mg/L. The more of carbon was released from substrates due to the higher concentration of carbon in substrates. The removal rate of TOC for three substrates could be summarized as following: soil > mixture of soil and sand > sand. The substrates with higher removal rate of TOC resulted from the higher microbial activity which was related to the higher concentration of carbon in substrates. However, TOC concentration in wastewater from mixture of sand, soil and peat at 12 d was increased due to relatively higher concentration of the stabilization combination organic carbon in peat. The capacity of removal of TOC was influenced by concentration and composition of carbon in substrates, and the higher microbial activity was related to the higher concentration of the easily decomposed organic carbon, which resulted in the higher removal rate of TOC.