Landfills are a key part of our waste management systems, but they pose a risk to the environment due to leachate, a liquid byproduct of decomposing waste that contains hazardous pollutants. Traditional landfill liners made of synthetic materials are effective but can be costly and have negative environmental impacts. A promising and sustainable alternative is a biochar-based landfill liner , which is the focus of a study by Rahul, Dr. Girish Bandi, and Dr. Shrinivas Khstagi in the JSRT Journal.

Biochar’s high porosityPorosity of biochar is a key factor in its effectiveness as a soil amendment and its ability to retain water and nutrients. Biochar’s porosity is influenced by feedstock type and pyrolysis temperature, and it plays a crucial role in microbial activity and overall soil health. Biochar More, large surface area, and chemical stability make it an ideal material for a landfill liner. The primary goal of using a biocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More liner is to use it as a filtration medium that can maintain a stable pHpH is a measure of how acidic or alkaline a substance is. A pH of 7 is neutral, while lower pH values indicate acidity and higher values indicate alkalinity. Biochars are normally alkaline and can influence soil pH, often increasing it, which can be beneficial More and enhance leachate retention and microbial activity. In a lab experiment, the researchers created a mini landfill model using layers of soil and biochar. They poured fresh leachate, collected from a municipal solid waste landfill, on top and then analyzed the liquid that drained from the bottom. The results demonstrated that the biochar liner significantly improved the quality of the leachate.

The physical and chemical characteristics of the leachate showed remarkable changes after passing through the biochar liner. The pH of the leachate increased from 4 to 7.8, effectively neutralizing it. The color of the leachate changed from black to yellow. Total hardness was significantly reduced from 91.64 mg/L to 16.8 mg/L. Chloride content decreased from 441.662 mg/L to 266.86 mg/L. Total solids, suspended solids, and dissolved solids were also reduced. Calcium hardness and magnesium hardness were lowered to 10 mg/L and 6.8 mg/L, respectively. Chemical Oxygen Demand (COD) saw a slight reduction from 3487 mg/L to 3000 mg/L.

While the biochar liner proved to be an effective filtration medium, the study’s conclusion notes that it was unable to prevent leachate penetration entirely. However, the results show that it holds promise as a sustainable alternative to conventional liners and could contribute to more effective and environmentally friendly waste management practices. Further research and collaboration are necessary to optimize the design and performance of these liners to ensure regulatory compliance.

Source: Rahul, Bandi, G., & Khstagi, S. (2025). Evaluating The Potential Of Biochar As Landfill Liner For Leachate Prevention. JSRT Journal, 3(9), 16-18.