疏浚底泥的养分特征及污染化学性质研究

Characteristic of nutrients and polluting chemistry in dredged sludge

本文以运河 (杭州段 )待疏浚底泥为材料 ,分析了疏浚底泥的养分特征及其污染化学性质。结果发现 ,疏浚底泥中含有较高的养分 ,其中有机质、P、K含量较高而N偏低 ;施入土壤后 ,有机质矿化很快 ,P的供应较为持久。疏浚底泥重金属含量较一般城市污泥低 ,基本低于污泥农用中污染物控制标准 ,可考虑直接使用以节约处置费用 ;重金属的有效态含量不高 ,相对活性顺序为Cd >Cu >Pb >Zn,直接大量施用会对种子发芽产生一定的毒害。供试作物种子对疏浚底泥毒害作用的反应不同 ,抗性顺序为青菜 >羊茅草 >三叶草。直接利用疏浚底泥比城市污泥具有更大的安全性 ,只要物种选取合适、用量恰当 ,是一种很好的肥源和复垦用土。

Characteristic of nutrients and polluting chemistry of dredged sludge from the Grand Canal were studied The result showed that the contents of nutrients were high in dredged sludge, but it was unbalance Contents of organic matter, phosphorus and potassium were high in dredged sludge, while that of nitrogen was low Decompose of organic matter was rapid when the dredged sludge applied to soil, while available phosphorus providing was permanent Contents of heavy metals in dredged sludge were significantly lower than sewage sludge and most of them lower than Agricultural Application Standard, so it is more economical to apply dredged sludge to land directly The available heavy metals in dredged sludge were low, relative active order was: Cd > Cu > Pb > Zn Dredged sludge have harmful effect on seed germination when applied to soil by large amount, while the reaction of different kind of seed was significantly different It could be conclude that dredged sludge can be used as fertilizer or amendment to reclaim land when the species of plant and application rate are properly selected