Adsorption study on leachate generated at the Gummidipoondi hazardous landfill site using groundnut shell and mango seed powder in sequential batch reactor

Abstract

In recent days, landfills emerged as an unavoidable source for heavy metals and have a calamitous impact over the environment. In precise, heavy metals and its disposal methods contribute excessive damage to the environment at higher rates. Hence, this paper attempts to treat heavy metal contaminated leachate collected from a hazardous waste landfill management site located at Gummidipoondi, Tamil Nadu using groundnut shell and mango seed. With numerous ways to treat the leachate, Sequential Batch Reactor (SBR) is preferred due to its low cost and operational efficiency in removing heavy metals. Five days of 8 hours cycle with five phases of treatment is carried out in SBR. The leachate from the hazardous landfill is characterized for heavy metals using ATR-FT-IR spectroscopy analysis and the concentration of heavy metals like Aluminum, Arsenic, Boron, Cadmium, Chromium, Copper, Iron, Potassium, Lithium, Nickel, Lead, Selenium, and Zinc were determined. The results after treatment showed that there is at least a 50% reduction in the heavy metals concentration present in the hazardous landfill’s leachate. The groundnut shell – SBR system attained maximum removal efficiency for the following heavy metals: 99% removal of lead, selenium and zinc, 98% removal of aluminum and cadmium, 68% removal of nickel, 67% removal of lithium, 56% removal of arsenic, and 44% of potassium. Furthermore, the mango seed – SBR system attained the maximum removal efficiency for the following heavy metals: 99% removal of lead and selenium, 95% of chromium, and 54% of boron.