太阳能光热蒸发技术及其在环境领域的应用进展

近年来,太阳能光热蒸发技术因化石能源危机成为各个领域的热点,相关学者尝试将其引入环境领域,以促进传统技术与新能源的结合,系统梳理该技术的应用现状和发展趋势,势必将极大促进其在环境领域的进一步拓展。基于此,文中深入、系统地总结了太阳能光热蒸发技术的研究现状,分析了金属等离子体、无机半导体、碳基、有机高分子等太阳能吸收体材料的性能以及未来发展方向,梳理了块体蒸发、界面蒸发、隔离蒸发这3种蒸发形式的发展脉络以及特点,全面介绍了其在海水淡化、消毒灭菌、污水处理等环境领域的应用,提出了该技术在环境领域的应用展望。

抗污型CFC/TiO_(2)光热织物的制备及其在海水淡化中的应用

太阳能光热海水蒸发被认为是解决淡水危机的有效策略,但实际海水中存在油污和有机污染物,长期蒸发过程中污染物会黏附在光热膜表面,致使膜的蒸发性能下降。为实现海水的长期抗污型蒸发,制备兼具光热和光催化性能的碳纤维布(CFC)/TiO_(2)织物。以CFC为衬底,通过水热法在其表面生长TiO_(2)纳米棒阵列(TiO_(2)纳米棒直径约为0.47μm、长度约为1.49μm)。结果显示:CFC/TiO_(2)织物表现出超亲水和超疏油特性,同时具有宽光谱(280~2500nm)光吸收性能(光吸收效率约为88%);在模拟太阳光激发下,CFC/TiO_(2)还可光催化降解有机污染物,如在200min内降解73%的盐酸四环素。将CFC/TiO_(2)光热薄膜构筑成倾斜式海水蒸发器,在模拟阳光(光强为1kW/m^(2))照射下,部分海水被蒸发,蒸发速率达1.68kg/(m^(2)·h),浓缩后的海水在织物底端滴落,长期蒸发不析盐。这种光热/光催化织物有望推动太阳能海水淡化走向实际应用。

More from less:improving solar steam generation by selectively removing a portion of evaporation surface

Using minimal photothermal material to achieve maximum evaporation rate is extremely important for practical applications of interfacial solar evaporation technology.In this work,we found that with the increase in the size of evaporation surfaces,the evaporation rate decreased.Both experimental and numerical simulation results confirmed that when the evaporation surface size increased,the middle portion of the evaporation surface acted as a‘‘dead evaporation zone”with little contribution to water evaporation.Based on this,the middle portion of the evaporation surface was selectively removed,and counterintuitively,both the evaporation rate and vapor output were increased due to the reconfigured and enhanced convection above the entire evaporation surface.As such,this work developed an important strategy to achieve a higher evaporation rate and increased vapour output while using less material.