受水车启发的、在饱和盐水中也能实现高效和稳定的太阳能淡化的旋转蒸发器

Waterwheel-inspired rotating evaporator for efficient and stable solar desalination even in saturated brine

太阳能海水淡化是解决全球淡水短缺的最有前景方法之一.然而,传统的蒸发体在高盐度海水中遭遇了盐累积带来的蒸发速率下降甚至失效的瓶颈.受古代水车的启发,本文开发了一种自适应旋转蒸发器,其可以在任意浓度的盐水中实现长期高效的太阳能海水淡化.这种蒸发器是一种双硫化物负载的滚筒式生物质炭.借助了木材天然的水传输通道和分层结构,蒸发器具有杰出的水供应和热定位能力.实验和数值模拟表明,归因于其低密度及独特的亲疏水特性,这个蒸发器能够在盐结晶产生的重心偏移下周期性转动以实现自动盐移除.这使得这个蒸发体甚至可以在饱和盐水(26.47%)中,24 h内保持2.8 kg m^(-2)h^(-1)的高蒸发速率,这是过去一直无法实现的.因此,这项概念验证工作展示了一种不受浓度和运行时间限制的、自旋转诱导脱盐的蒸发器.

Solar desalination is one of the most promising technologies to address global freshwater shortages.However,traditional evaporators encounter the bottleneck of reduced evaporation rate or even failure due to salt accumulation in high-salinity water.Inspired by ancient waterwheels,we have developed an adaptively rotating evaporator that enables long-term and efficient solar desalination in brines of any concentration.The evaporator is a sulphide-loaded drum-type biochar.Our experiments and numerical simulations show that this evaporator,thanks to its low density and unique hydrophilic property,rotates periodically under the center-of-gravity shift generated by salt accumulation,achieving selfremoval of salt.This allows it to maintain a high evaporation rate of 2.80 kg m^(-2)h^(-1)within 24 h even in saturated brine(26.47%),which was not achieved previously.This proof-of-concept work therefore demonstrates a concentration-and time-independent,self-rotation-induced solar evaporator.