新型天然海藻絮凝剂处理食品废水的研究

Research on flocculation of protein-bearing wastewater by a new natural alga flocculant

比较各种絮凝剂的优劣后,选用海藻直接制作天然高分子有机絮凝剂,采用正交表L9(34)设计试验方案。大量试验结果显示,用该絮凝剂处理COD初始质量浓度为3000～13000mg/L的蛋白废水,存在一个适宜的投加量和pH范围,投加质量浓度为12.5g/L、pH2～4时,COD去除率大于70%,最高可达79.56%;室温下絮凝反应快,生成絮体大,自然沉降快。研究表明,该絮凝剂可有效去除COD,操作条件温和,且无毒、无害、无重金属残留,可处理食品行业的蛋白废水,絮凝产物可回收作饲料添加剂,具有良好的开发前景。

According to the comparison of the advantages and disadvantages of each kind of flocculants, marine alga is selected as raw material to make a new natural macromolecule polymer flocculant directly. The orthogonal table is used to design series of tests. A number of flocculating experiences show that the flocculant is used for treating the protein-bearing wastwater with a starting concentration of 3×10^3～1.3×10^4 mg/L COD, while the amounts of the new flocculant are 12.5 g/L and the pH is adjusted to the range of 2 to 4 and the removal rate is over 70%, the highest efficiency of COD can be up to 79.56%. The flocculation phenomenon occurs quickly at room temperature, and flocculated products appear quite large so that the flocculated sediment settles rapidly by gravity. The research shows that the new flocculant has good prospects of development because it is not only able to reduce COD efficiently at moderate operation condition, but also nonpoisonous, harmless, and without heavymetal residue, so it can be applied to treat protein-bearing wastewater in food industry, and the flocculated sediment can be recovered as animal fodder additives.