生物预处理工艺去除废水中四环素类抗生素

Biological Pretreatment Process for Removal of Tetracyclines Antibiotic from Wastewater

针对四环素类抗生素(TCs)生产废水在生物处理过程中普遍存在的泡沫剧烈、污泥沉降困难、处理效率低等问题,提出了生物曝气—铁盐混凝预处理工艺。结果显示,生物预处理工艺既可以提高TCs去除率,又能够降低铁盐投加量,当铁盐投加量(以Fe计)为100 mg/L时,TCs去除率由27.5%提高到84.5%;对于未经生物预处理的废水,若要达到相同的TCs去除效果,铁盐投加量为600 mg/L。这可能是由于废水中77.8%的挥发性脂肪酸在生物预处理过程中被有效去除,从而降低了其对铁盐混凝去除TCs的干扰。经过生物预处理后,后续生物处理系统出水COD由531 mg/L降至199 mg/L,处理效果提升明显。

The biological treatment of tetracyclines(TCs) antibiotic production wastewater has the common problems such as large amount of foam, difficulty in sludge settlement and low treatment efficiency. To solve these problems, a pretreatment process consisting of biological aeration and iron salt coagulation was proposed. The biological pretreatment not only increased the TCs removal rate, but also reduced the dosage of iron salt. When the dosage of iron salt(calculated by Fe) was 100 mg/L, the TCs removal rate increased from 27.5% to 84.5%. To achieve the same TCs removal performance for wastewater without biological pretreatment, the dosage of iron salt was 600 mg/L. The reason might be due to the fact that 77.8% of volatile fatty acids in wastewater were effectively removed during the biological pretreatment process, thus reducing their interference to the removal of TCs by ferric coagulation. After the biological pretreatment, the COD in the effluent from the subsequent biological treatment system decreased from 531 mg/L to 199 mg/L, and the treatment performance was significantly improved.