Chang Chao, Tao Peng, Fu Benwei, Xu Jiale, Song Chengyi, Wu Jianbo, Shang Wen, Deng Tao
State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
ACS Omega. 2019 Feb 18;4(2):3546-3555. doi: 10.1021/acsomega.8b03573. eCollection 2019 Feb 28.
Solar steam generation is critical for many important solar-thermal applications, but is challenging to achieve under low solar flux due to the large evaporation enthalpy of water. Here, we demonstrate a three-dimensional porous solar-driven interfacial evaporator that can generate 100 °C steam under 1 sun illumination with a record high solar-to-steam conversion efficiency of 48%. The high steam generation efficiency is achieved by localizing solar-thermal heating at the evaporation surface and controlling the water supply onto the porous evaporator through tuning its surface wettability, which prevents overheating of the evaporator and thus minimizes conductive, convective, and radiative heat losses from the evaporator. The design of steam outlet located at the sidewall of the evaporator rather than from the solar absorber surface not only facilitates the collection of generated steam, but also avoids potential blockage of solar radiation by the condensing steam. The high-efficiency solar-driven evaporator has been used to generate hot steam for outdoor removal of paraffin on the wall of oil pipelines, offering a promising solution to mitigate the wax deposition issue in petroleum extraction processes.
太阳能蒸汽产生对于许多重要的太阳能热应用至关重要，但由于水的蒸发焓大，在低太阳通量下实现具有挑战性。在此，我们展示了一种三维多孔太阳能驱动界面蒸发器，该蒸发器在1个太阳光照下可产生100°C的蒸汽，太阳能到蒸汽的转换效率高达48%，创历史新高。通过将太阳能热加热定位在蒸发表面，并通过调节其表面润湿性来控制向多孔蒸发器的供水，实现了高蒸汽产生效率，这可防止蒸发器过热，从而将蒸发器的传导、对流和辐射热损失降至最低。蒸汽出口位于蒸发器侧壁而非太阳能吸收器表面的设计，不仅便于收集产生的蒸汽，还避免了冷凝蒸汽对太阳辐射的潜在阻挡。这种高效太阳能驱动蒸发器已用于产生热蒸汽，以在户外去除输油管道壁上的石蜡，为缓解石油开采过程中的蜡沉积问题提供了一种有前景的解决方案。
