A self‐salt‐cleaning architecture in cold vapor generation system for hypersaline brines

Abstract

Desalination of seawater with zero-liquid discharge is a major challenge. Here we developed a three-dimensional "umbrella" architecture to evaporate hypersaline brines of up to 20 wt% using solar-driven interfacial evaporation. By controlling the water pathway and the thickness of the evaporator films to manipulate the salt capacitance of the system, a stable evaporation rate of >2.6 kg m À2 h À1 was achieved over 4-day operation in the laboratory environment with minimized salt accumulation on evaporation surfaces. By placing the system in an outdoor environment with natural wind, the peak evaporation rate was improved to 9.05 kg m À2 h À1 . After a 4-day outdoor test, the total evaporated water by the umbrella system was 3.7Â more than the natural evaporation from a bulk water surface under identical environmental conditions. The predesigned water flow also controlled the local salt accumulation, resulting in easier salt removing and collection, which is highly desired for accelerated salt mining applications.

Photothermal Nanomaterials: A Powerful Light-to-Heat Converter

“…White fabric wicks in a floating multilayer solar evaporation structure have been used for delivering water and rejecting excess salts at the same time . A 3D umbrella architecture has been developed to guide the accumulated salts through the predesigned pathways without blocking the evaporative surface . A stable evaporation rate from a hypersaline brine with a salinity of 20 wt % is achieved over 4 day operation with minimal salt accumulation.…”

“…479 A 3D umbrella architecture has been developed to guide the accumulated salts through the predesigned pathways without blocking the evaporative surface. 455 A stable evaporation rate from a hypersaline brine with a salinity of 20 wt % is achieved over 4 day operation with minimal salt accumulation. In a proposed contactless configuration (Figure 16b), the solar absorber does not touch the water surface and transfers energy to the seawater through thermal radiation, effectively circumventing the fouling problem.…”

Smart Strategies for Light and Thermal Management in High‐Efficiency Solar Steam Generation

“…So far, classic tilted flat plate evaporators, [6,[174][175][176][177][178][179] cone evaporators, [60,68,180] and origami evaporators [94] have been designed to reduce the energy density of the light-receiving surface. We demonstrated a biface evaporator using an ultrablack metalorganic framework (MOF) foam that has a pine needle-like hierarchical structure.…”

Advances in photothermal regulation strategies: from efficient solar heating to daytime passive cooling

“…21d). 415 The as-designed top-down water flow controlled the accumulation of local salt, making it easier to collect salt. Some other 3D structures have been also used for salt production, such as cones (Fig.…”