腐殖土对活性污泥中重金属形态分布的影响

分别投加0,0.5,1,2,3和5g腐殖土(HS)于1000mL活性污泥中充分搅拌20d,采用Tessier五步提取法对其中锌、镍、铜、铅元素的形态分布进行分析研究,结果表明,投加腐殖土能明显改变活性污泥中重金属的形态分布.对锌元素,可交换离子态(F1)锌,碳酸盐结合态(F2)锌和铁锰氧化物结合态(F3)锌含量与HS投加量有显著负相关性(0.9266,0.9310,0.9144,置信度P0.01),硫化物及有机结合态(F4)含量与HS的投加量有显著的正相关性(0.9304,P0.01);对镍元素,F1镍和F2镍含量与HS的投加量具有显著的负相关性(0.9027,0.9724,P0.01),F4镍和残渣态(F5)镍含量与HS的投加量具有显著的正相关性(0.9188,0.9123,P0.01);对铜元素,F2铜含量与HS的投加量呈负相关性(0.7145,P0.05);对铅元素,F3铅和F4铅含量与HS投加量具有负相关性(0.7027,0.7635,P0.05),F5铅含量与HS投加量具有正相关性(0.7668,P0.05).投加腐殖土能明显降低活性污泥中锌,镍元素的潜在迁移能力.

Effects of humus soil on chemical speciation of heavy metals in activated sludge

A batch tests study was performed to evaluate the changes of heavy metal chemical speciation in sewage sludge with humus soil. Sewage sludge with humus soil (0, 0.5, 1, 2, 3, 5g) mix 20d in polyethylene flasks. The five stages of the Tessier sequential extraction method was employed to investigate changes in heavy metal fractions of Zn, Cu, Ni and Pb in sewage sludge with humus soil. The results showed that humus soil effected chemical speciation of heavy metals in sewage sludge significantly. Zinc: ion-exchange (F1) zinc, carbonate-bound (F2) zinc and iron-manganese oxide bound (F3) contents and HS dosage had significant negative correlation (0.9266, 0.9310, 0.9144, p<0.01), sulfides and organic-bound (F4) and HS dosage had a significant positive correlation (0.9304, p<0.01). Copper: F2 and HS dosage had a negative correlation (0.7145, p<0.05). Nickel: F1 and F2 nickel and HS dosage had significant negative correlation (0.9027, 0.9724, p<0.01), F4 nickel and residual (F5) and HS dosage had a significant positive correlation (0.9188, 0.9123, p<0.01). Lead: F3 and F4 lead and HS dosage had negative correlation (0.7027, 0.7635, p<0.05), F5 lead and HS dosage had a positive correlation (0.7668, , p<0.05). Adding humus significantly reduced the potential availability of zinc, copper, nickel, and lead in activated sludge.