堆肥污泥重金属在黄土中的淋滤特征

Leaching characteristics of heavy metals in compost sludge in loess

堆肥污泥中所含重金属是污泥堆肥土地利用最大的障碍,实验选用北方贫瘠的黄土作为供试样品,通过室内土柱淋滤实验,对堆肥污泥重金属在黄土中的淋滤特征进行了研究。结果显示,在0～40 cm的浅层淋滤层,各种重金属在黄土中的纵向迁移能力为:Pb>Zn>Ni>Cu,而在50～55 cm的深层淋滤层,Cd在黄土中的迁移能力相对其他4种重金属是比较强的;各种重金属在50～60 cm深层淋滤层中会出现二次富集,出现明显富集层。研究揭示了堆肥污泥重金属在黄土中的迁移特征,为有效控制和消除堆肥污泥土地利用中重金属的污染研究提供了理论依据。

The heavy metals in compost sludge are the greatest barriers facing land utilization. The barren loess in north China was selected as tested samples, and then the leaching rules of heavy metals from compost sludge in loess were investigated via laboratory leaching experiments of soil columns. The results show that the mobility of various heavy metals in loess follows the order of Pb 〉 Zn 〉 Ni 〉 Cu in 0 - 40 cm, while Cd is easier to migrate than the other ones in 50 - 55 cm. The enriching layer is obvious due to secondary enrichment of heavy metals in 50 - 60 cm. The study reveals the migration of heavy metals from compost sludge in loess and provides the theory basis for effective control and elimination of heavy metal pollution from compost sludge.