Immobilization of leachate's heavy metals using soil-zeolite column

Introduction: Soil hazardous heavy metal pollution is increasingly a decisive problem all over the world. One of theproblems associated with organic fertilizer factories is the discharge of leachate containing solid wastes. Theleachate percolates through the soil and where there is no proper leachate filtration, this discharge could bepotentially a primary pollution source of soil and water resources. Iran has limited water resources and oppositelylarge number of unused lands. Therefore, properly managed land treatment may be a suitable solution for thefiltration of leachate before it enters the environment or is reused as irrigation water. To investigate the potentialityof soil-zeolite in the immobilization of heavy metals and prevention of groundwater contamination, a lysimeterstudy was performed with two types of soil texture (clay loamy and loamy sand) and two levels of zeolite and ablank (0, 5, and 10%).Results: The results showed that soil with a clay loamy texture can adsorb heavy metals such as Cr3+, Pb2+, Ni2+,and Cd2+ from influent leachate stronger than soil with loamy sand texture. Application of zeolite had a significanteffect (p < 0.05) on Pb2+, Ni2+, and Cr3+ concentration in the effluent. Increasing applied zeolite, reduced theconcentrations of these heavy metals in the effluent. Furthermore, application of zeolite and irrigation with leachatedecreased the bulk density, hydraulic conductivity, and infiltration of the soil in all treatments.Conclusion: Briefly, this research indicated that land treatment is a good way to reduce leachate electricalconductivity (EC) and elimination of leachate heavy metals.

کلیدواژه ها:

Heavy metal ، Infiltration ، Leachate ، Saturated hydraulic conductivity ، Zeolite