Phytoremediation

 The Kankaria Coaching Depot in Ahmedabad has emerged as India’s first ‘water-neutral’ railway depot, showcasing innovative wastewater treatment and reuse. 

Core Technology: Phytoremediation

At the heart of this transformation is Phytoremediation, an eco-friendly method where plants are used to clean contaminated water, soil, and groundwater. 

How Phytoremediation Works: Phytoremediation uses natural plant processes to remove or neutralise pollutants, especially when contamination levels are low. Plants help prevent the spread of contaminants through wind, rain, and groundwater movement. 

Mechanisms of Cleanup: Plants clean contaminants through several natural processes:

• Storage: Contaminants are stored in roots, stems, or leaves
• Transformation: Harmful substances are converted into less toxic forms within the plant or root zone
• Volatilisation: Some contaminants are converted into vapours and released into the air
• Rhizodegradation: Contaminants stick to roots, where soil microbes break them down into safer compounds

Special Techniques

• Hydraulic Control: Trees absorb groundwater through roots, reducing the spread of contamination
• Constructed Wetlands: Engineered wetland systems use plants to naturally filter and purify wastewater

Limitations: Phytoremediation is most effective when contamination levels are low, as high pollutant concentrations can inhibit plant growth and slow the cleanup process.

Source: EPA