Potential of Sunflower to Extract Heavy Metals from Leachate

Abstract

The effectiveness of sunflower to extract harmful heavy metals from landfill leachate using phytoremediation technique was studied in this paper. A case study of Phursungi garbage dump yard located in Phursungi village in Pune, India was taken for this study as the residents have to deal with contaminated water throughout the year which induces diseases like dysentery, cholera, hepatitis, and heavy metal poisoning related diseases. There are various methods in phytoremediation, among which phytoextraction was used for this study. An experiment was carried out to test the removal efficiency of BOD, COD, TS, and heavy metals namely As, Hg and Pb from the soil by sunflowers with and without the addition of Vesicular Arbuscular Mycorrhizal (VAM) fungi. These fungi were used in soil to accelerate the process of extraction. Leachate diluted with 60% water was supplied such that the Hydraulic Retention Time (HRT) was more than 15 days (19 days achieved). The values of contaminants were checked for permissible limits according to standards for land disposal of treated leachates given in Municipal Solid Waste Management (MSW) rules, 2016 and Central Pollution Control Board (CPCB), India. The removal efficiency of Pb from soil was almost the same for plants supplied with VAM (67.92%) and plants without VAM (66.67%). Arsenic (As) removal efficiency was 100% for plants with and without VAM. For mercury (Hg), it was more for plants without VAM (96.29%) than plants with VAM (77.78). Thus, it was concluded that VAM was ineffective. Cd and Cr concentrations in leachate samples were observed to be within the permissible limits. Hence, they were discarded for calculation of removal efficiency.