海水pH对疏浚物中重金属释放的影响

Influence of Seawater pH on release of heavy metal in dredged materials of Yuandang hake

对厦门■■湖污染疏浚物中的Cd、Cu和Pb在不同pH的天然海水中溶出的模拟研究结果表明：在pH为5．0、6．5、8．3条件下，疏浚物中的Cd、Cu、Pb的释放率分别为80％～94％、4％～9％和1．0％～2，2％；在相同条件下，Cd、Cu、Pb的释放量（释放量）均随pH值增大而减少，释放量的顺序为Cd＞Cu＞Pb。讨论了pH对释放作用的影响及释放过程所遵循的动力学规律。

This paper intends to look into the factors influencing the release of heavy metals in polluted dredged materials. The release of Cd,Cu,Pb from dredged materials in seawater of different pH has been studied in simulation. The results show that (1 ) Cd,Cu,Pb are released from dredged materials into seawater in simulated different pH conditions, with release ratios of 80%～ 94 %, 4 %～ 9 %, 1 %～ 2. 2 % respectively. (2) Under the same conditions, the release and release ratio of Cd,Cu,Pb decrease with increasing pH. The release order of Cd, Cu, Pb from dredged materials is Cd>Cu>Pb. (3) It has been demonstrated that the exchang-adsorption kinetic model of solid-liquid interface proposed by the authors can be used to explain the release behaviors of heavy metals from dredged metarils and treat release kinetic of heavy metals.