Researchers Tanay Kumar, Hongying Zhao, and Xuehua Zhang from the Department of Mechanical and Industrial Engineering at the University of Toronto have developed a novel system for drying concentrated slurry waste, a common challenge in various industries. Their work, published in the journal Nature Sustainability, presents a sailboat evaporator with a root-like structure that leverages wind-assisted evaporation to dewater high-solid-content slurries more efficiently than conventional methods.
The researchers’ sailboat evaporator addresses a significant issue in industrial wastewater treatment: the slow drying process of concentrated slurries due to water entrapment between particles. The device’s root-like structure creates access to these disconnected water pockets, facilitating faster water conduction and evaporation. In their experiments, the evaporator’s long roots effectively extracted water even beneath a 150 cm deep supernatant water layer.
The team demonstrated that by replanting the evaporator to a separate location, they achieved an impressive evaporation rate of 4 kg/(m^2*h) at a solid concentration of nearly 80%. This represents a 25% increase compared to a non-replanted sample. Moreover, the evaporator maintained efficient evaporation over long periods, even at high solid concentrations, through hydrodynamic flushing of the roots. Outdoor experiments yielded dried residues with over 75% solid concentration, showcasing the system’s reliable performance with highly concentrated slurries.
The sailboat evaporator’s integration of renewable energy and efficient enhancement techniques makes it a scalable and sustainable solution for industrial wastewater dewatering. This technology could find practical applications in various sectors, including mining, chemical processing, and wastewater treatment plants, where efficient dewatering of concentrated slurries is crucial. By reducing the volume of slurry waste and improving drying efficiency, the sailboat evaporator could help lower operational costs and environmental impact for these industries.
Source: Kumar, T., Zhao, H., & Zhang, X. (2023). Combining Transport of Pendular Water with Wind-Assisted Interfacial Evaporation for Dewatering of Concentrated Slurry Waste. Nature Sustainability.
This article is based on research available at arXiv.