A study of treated municipal waste leachate and Zeolite effects on soils

As the world's population has grown and become more urban and affluent, waste production has raised drastically. Wastewater reuse has been identified as a way to alleviate water scarcity and improve crop productivity and environmental sustainability. To address the issue, a soil column experiment was carried out in a 3 × 3 factorial randomized block design including three treatments of adsorbents (non-pretreated leachate (L1), rice husk filtered leachate (L2), activated carbon filtered leachate (L3)) and three levels of zeolite (0, 5 and 10% by soil weight).A decrease in drainage water volume through the experiment period was observed. Application of zeolite at 5% level could improve soil removal efficiency and had a positive impact on the quality of the wastewater, as indicated by changes in EC, Na+, Ca2++Mg2+, Cl- (decreased by 22%, 15%, 24%, 15% respectively) and total P (increased by 12%) for treatment of leachate. However, adding 10% zeolite did not make a significant difference (p<0.05). Adsorbents used in the experiment had a significant effect (p<0.05) on the parameters such as N-NH4+, SAR, total P and Na+ content. Changes in most parameters for the L3 treatment were statistically significant (p<0.05) compared to other leachates (less N-NH4+ (40%), total P (33%) and more Ca2++Mg2+ (14.3%), Na+ (14%)) indicating an increase in adsorbent efficiency due to rice husk activation. Therefore, it can be concluded that application of zeolite can improve soil removal efficiency for treatment of leachate, but the rates of application can be case sensitive depending on the soil and the type of zeolite.