Abstract: Dredged sediment is one of the important measures to solve the problem of eutrophication. How to effectively treat dredged sediment has become a difficult issue to be solved in the present. Land utilization is one of the ways to effectively absorb dredged sediment, which however will cause soil nutrients loss, especially phosphorus loss. Taking red mud and fly ash as raw materials and using them for phosphorus stabilization, this paper studied the character of dredged sediment, effect of mixing solid stabilizer on pH of dredged sediment, and effect of stabilization time and dosage of solid stabilizer on phosphorus leaching. The results showed that the pH of dredged sediment increased with the stabilizer dosage increasing. The phosphorus leaching decreased with the stabilization time increasing. The phosphorus leaching increased with the increasing of red mud dosage. While, the phosphorus leaching decreased with the increasing dosage of fly ash and mixture of red mud and fly ash. Therefore, the balanced mixture of fly ash and red mud and fly ash can effectively stabilize phosphorus in dredged sediment.

Key words: dredged sediment, red mud, fly ash, phosphorus

摘要： 底泥疏浚是解决水体富营养化的重要举措之一，如何有效处理疏浚底泥已经成为亟待解决的难题。土地利用是有效吸纳疏浚底泥的方法之一，但却存在营养元素尤其是磷元素容易流失的问题。以铝业矿渣赤泥和煤燃烧副产物粉煤灰为原料，将其用于疏浚底泥中磷的固稳，考察了疏浚底泥的性质、固稳剂对疏浚底泥pH的影响、固稳时间以及固稳剂添加量对磷浸出量的影响。结果表明:疏浚底泥的pH随着固稳剂添加量的增加而升高，磷的浸出量随着固稳时间的延长而降低；对于掺混赤泥的疏浚底泥，磷的浸出量随着赤泥添加量的增加而增加，而对于掺混粉煤灰或赤泥与粉煤灰等量混合的疏浚底泥，磷的浸出量随着固稳剂添加量的增加而降低。粉煤灰或赤泥与粉煤灰等量混合作为固稳剂均能够有效固稳疏浚底泥中的磷。

关键词: 疏浚底泥, 赤泥, 粉煤灰, 磷