污泥中氮磷在灰潮土上的淋滤特性研究

污泥土地利用时,其中富含的氮、磷可能会对地下水造成污染.本研究通过测定模拟土柱淋洗液,分析了两种污泥中氮、磷在灰潮土中的迁移性.测定项目包括:pH、EC、硝态氮、全磷.结果表明,土壤淋洗液的pH变化不大,电导率、硝态氮、全磷则明显增大,并随淋洗次数的增多逐渐恢复到空白水平,而且淋洗液的电导率与硝态氮和全磷间存在较好的正相关关系.施用量程桥污泥控制在30%,竹园污泥在10%以内就不会对地下水造成氮、磷污染.

Leaching characteristics of nitrogen and phosphorus in the grey-fluvo-aquic soil receiving sludge

The present paper aims to introduce the authors' study on leaching characteristics of Nitrogen and Phosphorus in the grey-fluvo-aquic soil receiving sludge. As is known, nitrogen and phosphorus in sludge may pollute underground water when the sludge is used to the soil. General speaking, their leaching characteristics to the grey-fluvo-aquic soil can be assessed by means of two kinds of sludges onto the soil columns. In our research, the soil had been applied 10%, 20% and 30% for Chenqiao sludge, 10%, 20% and 45% for Zhuyuan sludge. The leachates were analyzed for pH, EC, nitrate and total phosphorus. The results of the exp;eriment show that: the leachates' pH had little variance, but EC, nitrate and total phosphorus can increase significantly, and till then it would quickly return to the original controlled experiment level with irrigation. Besides, EC may have positive correlation with nitrate and total phosphorus. In addition, underground water will not be polluted by nitrate with the application of sludge at the controlled level within the range of 30% for Chenqiao sludge and 10% for Zhuyuan sludge, it will neither be polluted by the phosphorus within that range.