Brackish Water Treatment by Interfacial Thermal Desalination Using a Novel Sustainable Organic Material for Tropical Regions

The main vertical to achieve this availability of freshwater and sanitation. The issue of water scarcity is no longer a future concern; it is already affecting billions of individuals daily. India has around 4% of these freshwater resources to support around 18% of the world's population. Due to this disproportionate distribution of water resources, it becomes hard to precisely fulfill the demand for freshwater. India's coastline spans 7,517 kilometers, including the mainland, Lakshadweep Islands, and the Andaman and Nicobar Islands. Furthermore, a substantial part of India experiences an average solar radiation ranging from 4 to 7 kWh/m²/day for approximately 300 to 330 days. Hence, to ensure freshwater availability for water-stressed populations, we must implement sustainable, eco-friendly, and green sanitation technology to curtail water scarcity and healthy well-being.
In this experimental setup, to enhance the performance of an optimized model of solar still, absorber surface modification was done using a carbon-based organic framework derived from biomass with an attribute of high solar absorption coefficient with an extensive spectrum range. Brackish water (1000<TDS <10000ppm) first passes through coarse mesh-size filters to separate the large-size contaminants. Subsequently, it passes through a solar glass evaporator decorated with lab-developed photothermic material to evaporate basin water. Under one sun condition, modified single slope solar still produced 848 ml/m²/h freshwater with high photothermal conversion efficiency against 690 ml/m²/h with a conventional model. Under the constrained working conditions, the expected life would be more than 10 years with minimum initial cost and bare minimum yearly-maintained cost. To adhere to the self-sustainable house concept, the desalination unit can be installed on the roof along with PV panels to make an off-grid house. At the household and community level, this innovative brackish water treatment and recycling technique will improve the health and well-being of a water-stressed population.