强化混凝控制有机物和残余铝的试验研究

摘要

The natural organic matter ( NOM) in water may produce carcinogens in the chlorination process. It is necessary to find a highly efficient method of NOM removal. In this paper, the effects of hydraulic conditions, pH value and Al2 ( SO4) 3 dosage on coagulation are studied with the enhanced coag ulation technology. The results show that the enhanced coagulation technology can remove NOM efficient ly, while controlling the residual Aluminum within the standard. The TOC decreases quickly with in creasing Al2 ( SO4) 3 dosage, but the removal rale remains stable when dosage is over 0. 2 mmol/L. The residual Aluminum decreases with the rising of pH value until 8. 0, and then increases. The TOC of re sidual organic matters is controlled at about 1.4 mg/L and residual aluminum is kept below 0. 05 mg/L in water with pH value of 8. 0 and Al2 (SO4) 3 dosage of 0. 3 mmol/L.%采用强化混凝技术,研究了水力条件、混凝剂投加量和pH值等因素对混凝效果的影响.结果表明,强化混凝技术能有效地去除NOM,而且控制残余铝量不超标.TOC随Al2(SO4)3投加量的增加而显著降低,投加量大于0.2 mmol/L后,去除率基本保持稳定.在pH值为8.0时残余铝含量最低.调节pH在8.0,投加量为0.3 mmol/L,可控制水中有机物的TOC在1.4 mg∥L左右,残余铝量在0.05 mg/L以下.