李氏禾净化含重金属生活污水的实验

Experiment on Treatment of Sewage Containing Heavy Metal by Leersia hexandra Swartz

采用水培方法设置了CK(0%)、40%、50%、60%、70%、80%、90%和100%等8个生活污水浓度比例梯度,在相同李氏禾(Leersia hexandra Swartz)株数的基础上,分别投加Cr6+、Cu2+和Ni2+等金属离子,研究铬超富集植物李氏禾对重金属、有机污染物(COD)、氨氮及总磷去除效果。结果表明,李氏禾对废水中Cr6+、Cu2+和Ni2+的去除能力很强,氨氮和总磷的去除效率分别可达到98%和90%以上,对COD降解可达80%以上。李氏禾对3种重金属的吸收结果表明,复合污染废水中生活污水含量越高,越有利于李氏禾对Cr6+和Ni2+的净化,而不利于对Cu2+的净化。

To investigate removal of heavy metals（Cr^6＋,Cu^2＋ and Ni^2＋）, organic pollutants（COD）, ammonia nitrogen and total phosphorus（TP） from wastewater by Leersia hexandra Swartz, 8 different sewage gradients including 0%, 40%, 50%, 60%,70%, 80%, 90% and 100% were designed, and Cu, Cr and Ni were added respectively. The capacity of L. hexandra to purify waters polluted by Cr^6＋, Cu^2＋and Ni^2＋was investigated. Results showed that this plant has a good ability to remove the three metals from water, and more than 98% of ammonia nitrogen in the wastewater was removed by L. hexandra. The removal rates were above 90% for TP and 80% for COD. The removal of Cu, Cr and Ni by L. hexandra indicated that higher level of sewage was favorable for the removal of Cr^6＋and Ni^2＋, but unfavorable for the removal of Cu^2＋.