Development of a novel solar energy controllable Linear Fresnel Photoreactor (LFP) for high-efficiency photocatalytic wastewater treatment under actual weather

Abstract Solar-energy-enabled photocatalysis is promising for wastewater treatment. However, due to the changes in the solar position and variable weather conditions, providing optimized light and temperature for photocatalysis under actual weather remains to be a technical difficulty. In this study, a novel Linear Fresnel Photoreactor (LFP) was firstly developed for wastewater treatment. LFP could achieve effective adjustment of sunlight by flexibly controlling 6 mirrors according to solar position and weather conditions. On sunny condition, LFP could maintain the optimal light irradiance and temperature, while on overcast condition it could provide the highest possible light irradiance and temperature. In the comparative experiments between LFP and Inclined Plate Collector (IPC) (as control reactor) which passively receive sunlight, the Rhodamine B degradation efficiencies in LFP were 2.19 folds, 1.5 folds and 2.28 folds higher than control under the temporarily overcast, totally to slightly overcast and sunny conditions, respectively. In addition, the efficiencies of Amoxicillin degradation and Escherichia coli disinfection in LFP were also 2 folds and 1.37 folds higher than control in sunny conditions, respectively. Furthermore, whole-year estimation indicated that LFP is effective to optimize light irradiance and temperature in typical densely populated areas of the world to achieve high-efficiency wastewater treatment. These results proved that LFP, as an effective solar energy controllable reactor, has great potential in promoting the development of green wastewater treatment infrastructure to improve global public health and achieve eco-friendly society.