A Passive High-Temperature High-Pressure Solar Steam Generator for Medical Sterilization

Abstract

Solar steam generation at the sterilization condition suffers from low efficiency, especially in passive solar thermal devices. We developed a stationary solar collector with a transparent aerogel layer to achieve efficient solar steam generation via thermal concentration. In field tests performed in Mumbai, India, the device generated steam at 100 C with 56% efficiency and successfully powered a sterilization cycle following the standard sterilization protocol. Our work shows the potential of solar thermal technology in steam generation and other applications.

Highly efficient and salt rejecting solar evaporation via a wick-free confined water layer

“…ater scarcity has become a severe challenge for humanity since two-thirds of the global population is affected by water shortage 1 . Owing to the significant potential for clean water production, highly efficient solar evaporation by localizing the solar-thermal conversion process near the evaporating interface has attracted tremendous research interest in passive vapor generation [2][3][4][5][6][7] , seawater desalination [8][9][10][11][12][13] , wastewater treatment [14][15][16][17][18] , and medical sterilization 19 . However, due to the ultralow diffusivity of salt in water (~10 −9 m 2 s −1 , as a reference in comparison to the diffusivity of vapor in air is ~10 −5 m 2 s −1 ), there is significant salt accumulation, which induces undesirable fouling, reduces evaporation rate, and degrades device reliability.…”

Passive, high-efficiency thermally-localized solar desalination

“…4c and d, low-cost bubble wrap and silica aerogel constituted the convection covers. 28,34 Note that for solar absorbers operating at high temperatures (≈ 100 ℃ or even higher) under solar concentration 29,30,80,81 , thermal concentration 28,82 , or contactless heating, 63,64 it is particularly important to use spectrally selective solar absorbers and convection covers to maximize the solar-vapor conversion efficiency. 78 To minimize heat loss from the evaporator to bulk water, it is also necessary to reduce conduction heat transfer.…”

Multifunctional photothermal materials based on natural pumices for high efficiency solar‐driven interface evaporator

“…At present, the multifunctional photothermal materials requires the following aspects: high efficiency of photothermal conversion, [1][2][3][4][5][6][7][8] excellent salt resistance, [9][10][11][12][13][14][15] bactericidal and bacteriostatic effect, [16][17][18][19][20] anti-pollution capacity, [21][22][23][24][25][26] multi-effect utilization of energy, [27][28][29] and so on. In recent years, a lot of photothermal materials for solar-driven interface evaporator (SDIE) have been developed.…”

“…The representative applications of bactericidal and bacteriostatic SDIE are mainly reflected in two aspects. The first is to directly kill bacteria through saturated high-temperature steam, [16][17][18] and the other is to use the bacteriostatic and bactericidal substances of the SDIE for disinfection and sterilization. 19,20 Anti-fouling and decontamination-type SDIE is very important for sewage treatment.…”