NaClO/Fe2+强化含藻污泥脱水性能与机理研究

NaClO/Fe2+ Coagulation to Improve Dewatering Performance of Algae-containing Sludge and Mechanism Investigation

摘要:

次氯酸钠强化二价铁盐混凝能够有效提升含藻污泥的脱水性能与效果。当NaClO质量浓度为1.5～2.0 mg·L^-1时，含藻污泥的脱水性能达到最佳。过量NaClO的氧化作用使得藻细胞完整性受损，胞内物质外溢，阻碍了细胞间水分的释放，导致脱水性能下降。Fe²⁺被NaClO氧化后原位生成Fe³⁺，继而形成Fe（OH）₃，强化了高藻水的混凝效果；NaClO使得部分亲水性胞外聚合物降解，其中蛋白质和多糖等组分含量降低，有利于藻细胞间水分释放，从而提高了含藻污泥的脱水性能。此外，NaClO强化二价铁盐混凝对溶解性有机物的去除率由74%上升至90%，腐殖质类大分子和芳香族化合物的含量也有所下降，提升了水质净化效果。

Abstract:

Sodium hypochlorite/ferrous salt coagulation can efficiently improve the dewatering performance and effect of algae-containing sludge. When the NaClO dosage was 1.5～2.0 mg·L^-1， the dewatering performance reached the best. The oxidizing property of excessive NaClO damaged the integrity of algae cells. The overflow of intracellular substances hindered the release of water between cells， leading to the decrease of dewatering performance. Under the oxidation effect of NaClO， Fe²⁺ was transformed into Fe³⁺ in situ and further formed Fe（OH）₃， which enhanced the coagulation effect. The hydrophilic components of extracellular polymeric substances such as protein and polysaccharides were partially degraded by NaClO， which was beneficial to the release of water between cells. Hence， the dewatering performance was improved. In addition， the removal rate of dissolved organic matter by NaClO/Fe²⁺ coagulation increased from 74% to 90%， and the content of humus macromolecules and aromatic compounds was also reduced， improving the purification effect of algae-laden water.