Abstract: A strain of bioflocculant-generating bacterium, named G-420 was isolated from activated sludge. The flocculating property of MBF-420 produced by flocculant-generated bacteria G-420 was studied. It was shown that the bioflocculant was an extra-cellular production and the flocculating active components were mainly distributed in the fermentation broth. MBF-420 had good flocculating capability and could achieve the flocculating rate of 95.99 % for kaolin suspension at a dosage of 2.4 mg·L-1. Meanwhile, MBF-420 was heat-stable, while it was kept in boiling water for 30 min, the flocculating rate was still retained above 93%. It also could keep high flocculating activity in a wide range of pH from 1 to 10, and the best flocculating activity was attained when the pH value was 4. The addition of metal ion could increase the flocculation rate and Ca2+ was the best metal ion. It also presented a good flocculating effect on different suspensions.

摘要： 从活性污泥中分离得到一株微生物絮凝剂产生菌G-420，并对该菌所产絮凝剂MBF-420的絮凝特性进行了研究。实验结果表明：该絮凝剂为微生物胞外产物，絮凝活性成分主要分布在发酵液中；该絮凝剂有良好的热稳定性，于100 ℃水浴中保持30 min，絮凝率仍能达到93 %以上；具有较强的耐酸碱性；当絮凝剂用量为2.4 mg·L－1时，絮凝率高达95.99 %；以金属离子作助凝剂能有效提高絮凝率，最适宜的助凝剂为Ca2+；该絮凝剂对高岭土、土壤悬液、矿石粉等几种常见悬浊液体系均有较好絮凝效果。