Clean Carbon Cycle via High‐Performing and Low‐Cost Solar‐Driven Production of Freshwater

Valerio Mazzone,Christof M Aegerter,Andrea Fratalocchi,Marcella Bonifazi,Aluizio M Cruz

doi:10.1002/adsu.202100217

Valerio Mazzone, Christof M Aegerter + Show 3 more

Open Access

https://doi.org/10.1002/adsu.202100217

Copy DOI

Abstract

AbstractWhile renewable power available worldwide costs increasingly less than the least expensive option based on fossil fuels, countries continue to increase their coal‐fired capacity, which should conversely fall by 80% within a decade to limit global warming effects. To address the challenges to the implementation of such an aim, here, a path is explored that leverages on a previously unrecognized aspect of coal, opening to a new solar‐driven carbon cycle that is environmentally friendly. By engineering the porosity matrix of coal into a suitably designed compressed volumetric structure, and by coupling it with a network of cotton fibers, it is possible to create a record performing device for freshwater production, with a desalination rate per raw material cost evaluated at 1.39 kg h $ at one sun intensity. This value is between two and three times higher than any other solar desalination device proposed to date. These results could envision a clean and socially sustainable cycle for carbon materials that, while enabling an enhanced water economy with global access to freshwater and sanitation, poses zero risks of reinjecting into the environment through competing economies in the fossil's market.

Highlights

While renewable power available worldwide costs increasingly less than the least expensive option based on fossil fuels, countries continue to increase current crisis of unregulated CO2 emission levels, to mitigate climate change through an umbrella of “4Rs” that could reduce, their coal-fired capacity, which should fall by 80% within a decade to limit global warming effects
At the core of change while promoting carbon economy (CCE) is a wide range of technologies, ranging from negative emissions to carbon capture/storage and natural climate solutions, which aim to establish suitably designed compressed volumetric structure, and by coupling it with a clean energy transition pathways toward network of cotton fibers, it is possible to create a record performing device for freshwater production, with a desalination rate per raw material cost evaluated at 1.39 kg h−1 $−1 at one sun intensity
We implemented and characterized a solar-driven water generator composed of carbonized compressed powder and cotton fibers

Summary

Material and Sample Preparation

Either in fossil form or human-made carbonized structures (charcoal), has many advantages for solar steam generation in terms of strong light absorption, worldwide availability, and low cost. When used as a water desalination system, the CCP exploits the synergy between cotton fibers and carbonized powder The former is a primary water transportation system inside the CCP, and the latter constitutes both a volumetric light absorber and a secondary liquid transportation system. Capillary forces act on the liquid inside the CCP and transport the water from the bulk toward the upper surface and lateral walls (Figure 1d, red arrows), where broadband light absorption from the sun promotes the process of steam generation. By using a computer numerical control facility, we manufacture the holes in Figure 1d that accommodate the cotton fibers, passing the cotton across the gaps at different heights following perpendicular directions (Figure 1d) This approach guarantees a more considerable diffusion of water inside the CCP volume. By acting together with the CCP, the cotton fibers prevent organic and inorganic macro-molecules from being absorbed by the other thermally active part of the device, enabling freshwater production with low cost and high efficiency

Sample Characterization

Outdoor Experiment

Discussion and Conclusions

Findings

Data Availability Statement