水铁矿促进湿地植物净化含砷微污染水源水的试验研究

为了研究水铁矿促进湿地植物净化微污染水体中砷的效果及机理,选用美人蕉,添加不同比例水铁矿的石英砂构建微型垂直流人工湿地,考察含砷微污染水连续漫灌条件下美人蕉根表铁膜中铁含量及砷在湿地基质和植物茎叶中的分布规律。结果表明:湿地基质中水铁矿的添加剂量在200 mg/kg以内,湿地基质吸附截留砷的能力随水铁矿添加剂量的增加而提高;超过200 mg/kg以后,增加水铁矿对湿地基质截留砷的能力影响不明显。美人蕉根表铁膜中的铁含量随湿地基质中水铁矿添加剂量(在50~1 200 mg/kg范围内)的增加而增加;渍水状态下的美人蕉净化含砷的微污染水,根表铁膜中铁含量在100 mg/kg左右,最有利于砷的吸收和最终去除。

Study on ferrihydrite promotes the purification of slightly polluted source water containing arsenic by wetland plants

In order to study the effect and mechanism of ferrihydrite promotes the purification of slightly polluted source water containing arsenic by wetland plants. A miniature vertical flow constructed wetland was constructed by using Canna and quartz sand with different proportions of ferrihydrite, the iron content in iron plaque of Canna, Distribution of arsenic in wetland matrix and plant stems and leaves were investigated under arsenic containing micro polluted water continuous flooding. The results showed that when the added dosage of ferrihydrite in wetland matrix was less than 200mg/kg, the ability of adsorption and retention of arsenic in the wetland matrix increases with the increase of the dosage of ferrihydrite, while after more than 200mg/kg, the increase of water iron ore has no obvious influence on the ability of arsenic retention by wetland substrate; The iron content in the iron plaque of Canna Roots increased with the increase of the iron added amount (within 50-1200 mg/kg) in the wetland matrix. Canna purifying micro polluted water containing arsenic under waterlogging condition, when iron content of iron plaque was about 100mg/kg,Most beneficial foe arsenic absorption and final removal byCanna.