Hydrologists at IIT Roorkee have developed an "indigenous, low-cost technology" to address wastewater challenges linked to hydroponic farming. Hydroponics involves growing plants without soil using nutrient-rich water, but the wastewater generated often contains high concentrations of nitrate, phosphate and ammonia. If released untreated, it can cause eutrophication in natural water bodies, leading to algal blooms and oxygen depletion that threaten aquatic life.
To address this, researchers from the departments of hydrology and renewable energy at IIT Roorkee developed a cost-effective treatment technology based on microalgal photogranules. The study has been published in the international journal ACS ES&T Water.
Conventional microalgae-based wastewater treatment systems face a major limitation: harvesting microscopic algae from water is energy-intensive and typically requires expensive centrifuges or chemical additives. The IIT Roorkee team addressed this challenge by inducing microalgae to self-aggregate into dense, spherical granules. These photogranules contain microalgae, bacteria and cyanobacteria working together in symbiosis.
The technology uses a light-driven photogranule reactor, where microorganisms self-aggregate into dense spherical granules under controlled mixing and illumination. These granules simultaneously remove nitrogen, phosphorus and organic pollutants from hydroponic wastewater through photosynthesis and microbial metabolism.
Read more at Times of India
