不同固化配方对污染底泥中氮磷稳定性的影响研究OA

Four different solidification formulas were employed to treat contaminated sediment,and the release patterns of nitrogen and phosphorus from the solidified sediment under both static and dynamic conditions were investigated.The results showed that the nitrogen and phosphorus release amounts from the four solidified sediments with solidification agents added were significantly lower than those from the air-dried original sediment.Among the solidification formulas,the cement content was identified as the dominant factor affecting the release fluxes of nitrogen and phosphorus.Under the experimental conditions,the order of nitrogen and phosphorus release fluxes was:fully disturbed>aerated disturbance>static.Mechanistic analysis indicated that cement and lime in the solidification agents significantly reduced the content of transformable total nitrogen(TTN)and total nitrogen(TN),especially the strong alkaline extractable fraction nitrogen(SAEF-N),thereby inhibiting nitrogen release.Cement slightly increased the content of weakly bound phosphorus(NH4 Cl-P)in the sediment but simultaneously decreased the contents of iron-bound phosphorus(Fe-P)and aluminum-bound phosphorus(Al-P),promoting the transformation of phosphorus into more stable forms.The findings provide a scientific basis for the treatment and disposal of contaminated sediment,while practical engineering applications require further consideration of sediment properties and external environmental influences.