The Chemical Kinetics in Migration of Organophosphorus in Clay with Different pH

In order to study the characters of chemical kinetics for organophosphorus migration in clay with different pH, waste of organophosphorus was put under pressure to leakage permeating the cohesive soil, and simulate the process of organophosphorus leakage permeating the Aquitard, searching the characters of chemical kinetics for organophosphorus migration in clay with different pH. It is shown that the ability of migration of organophosphorus leakage permeating the cohesive soil fall with increase of pH; the penetration rate of organophosphorus is about 1.25% when pH is 7.5, organophosphorus has not penetrated the cohesive soil when pH is equal or greater than 8.5. The effect of retardarce is obvious. Concentration of PO43？ that comes from the mineralization of organophosphorus is lowered slightly with increases of pH of clay, and rise with extension of time. The Chemical Kinetics equation is log c=-0.1pH＋0.2172k1t＋S.

不同pH值黏土层对有机磷渗透的影响分析

采用施压条件下有机磷溶液渗透通过粘性土层的实验,模拟有机磷越流通过弱透水层的过程,研究粘土层pH值不同时对有机磷渗透迁移的影响规律。分析认为,有机磷渗透通过粘性土层的能力随着土层pH值的升高而降低;pH为7.5时矿化率为98.75%,迁移率为1.25%,土层pH值≥8.5时有机磷未穿透粘土层,阻滞效果明显。矿化形成的PO34-离子占总磷的百分比随着土层pH值的升高而增加,与Ca2+离子结合形成沉淀物的能力增强,粘土pH值的升高对有机磷的降解转化具有明显的促进作用。

酸碱度对山地农村沟渠底泥营养盐动态迁移的影响

【目的】酸碱度是影响沟渠底泥营养盐迁移释放的关键性因子。探究不同pH条件下山地农村沟渠底泥营养盐释放迁移的动态变化,为农村生态环境治理提供理论依据。【方法】采集滇池流域典型山地农村沟渠底泥,通过室内模拟实验测定未灭菌与灭菌处理下不同pH(5.5、7.5、9.5、11.5)条件的底泥、上覆水中营养盐含量,估算底泥-水界面营养盐释放通量。【结果】底泥中总氮质量分数随着pH升高而减少,未灭菌组强碱性(pH 11.5)和酸性(pH 5.5)条件下总氮释放通量分别是对照(pH 7.5)的8和4倍,灭菌组均为对照的2倍。上覆水中溶解性总磷质量浓度和释放通量随pH升高而增加,未灭菌组强碱性(pH 11.5)和弱碱性(pH 9.5)条件下溶解性总磷释放通量分别是对照的12和4倍,灭菌组分别是对照的30和15倍;未灭菌组溶解性总磷释放通量高于灭菌组。冗余分析表明:酸性条件促进底泥中钙结合态磷(CaP)的释放,碱性(p H≥9.5)条件促进总氮、总磷和铁铝结合态磷(Fe/Al-P)的释放,中性(pH 7.5)条件对底泥中氮/磷释放影响较小。【结论】碱性(pH≥9.5)和酸性显著促进山地农村沟渠底泥中氮磷营养盐释放,中性条件下释放量最小。底泥灭菌处理降低了不同pH下的微生物活性,阻碍山地农村沟渠底泥中氮磷向上覆水体迁移释放。图6表1参36。