Guwahati, Oct 13: Researchers at the Indian Institute of Technology-Guwahati (IIT-G) have produced a novel heat transfer fluid based on nanofluids, capable of efficiently transferring heat generated using solar power to desalination systems.
Desalination is a process that extracts freshwater from saltwater.
This advancement, the research team claims, promises a practical solution for producing potable water from seawater, addressing the pressing issue of global water scarcity.
The researchers, led by Prof. Tamal Banerjee from the department of chemical engineering, IIT-G, leveraged the exceptional thermal conductivity and stability of graphene oxide dispersed in deep eutectic solvent (DES), which is a safe and environmentally-friendly solvent.
By modifying graphene oxide with an amine functionality, the research team achieved enhanced dispersion stability, overcoming the tendency of nanoparticles to clump together.
As the world faces a severe water shortage that outpaces population growth, the demand for desalination has become critical. However, conventional desalination methods use heat generated by burning fossil fuels, leading to economic and environmental challenges. Concentrated solar power (CSP) that uses sunlight to generate heat is a promising solution to this problem.
The challenge of using CSP for desalination lies in transferring the generated heat from CSP systems to the desalination plants. Common heat transfer fluids, such as molten salts and synthetic oils, present drawbacks, including high melting points and low heat transfer efficiencies. Additionally, India’s dependence on imported heat transfer fluids escalates capital costs. To address these issues, the IIT-G researchers explored the use of nanofluids, suspensions of nanoparticles in DES, as an efficient alternative.
Elaborating on their work, research scholar Nipu Kumar Das, said, “We developed a nanoparticle-dispersed deep eutectic solvent (NDDES) through precise mixing, demonstrating outstanding thermal conductivity and stability. This breakthrough has immense potential for sustainable energy applications, particularly in solar energy and desalination.”
The study, IIT-G claims, has demonstrated the superior thermal properties of nanofluids in heat transfer applications.
The researchers have also proposed an innovative desalination system utilising nanofluids and a heat exchanger. This system aims to achieve a gain output ratio (GOR) of around 10, indicating the potential for generating a larger quantity of freshwater.
Notably, the research findings have been published in the journal Sustainable Chemistry and Engineering by the American Chemical Society. The research work was funded by the Centre’s department of science and technology (DST).