(561b) Experimental Study on a Solar Falling-Film Photochemical Hybrid System for the Decolorization of Azo Dyes

Based on the solar photochemical reactors with flow channel (SPC), a new hybrid system that integrated solar falling-film photochemical reactor with photovoltaics (SFPC) was first presented to achieve the dye decolorization and the electricity generation simultaneously. Persulfate was chosen as the photochemical oxidant, all the experiments were performed outdoors in Tianjin, China. In this work, the spectrum transmittance, decolorization efficiency and the PV panel parameters were analyzed, by dealing with different concentration of acid red 26 (AR26) and acid brown 14 (AB14) in different systems.

The structural modification on the reactor improved the optical transmission efficiency of the SFPC system. The actual optical loss was only 1.6% in the SFPC system in contrast of 21.9% in the SPC system. The results confirmed that the remove of borosilicate glass and the reduced water thickness greatly decreased the optical loss in the SFPC system. The performance of the dye decolorization and the PV panel parameters were also tested. Compared with the SPC system, the SFPC system greatly enhanced the decolorization efficiency, the accumulated ultraviolet needed shortened 33.64%, the I_sc, P_max and of the PV panel increased 26.97%, 30.47%, 2.9% respectively, when dealing with the 50 mg/L AR26. And we will do the research on the degradation mechanism of the dyes in the future work.

The flow rate of the wastewater was also optimized. When the flow rate increased from 200 L/h to 1000 L/h, the reaction kinetic constants of AR26 and AB14 increased by 0.3 and 0.97 times respectively. However, the output power of the panel decreased and the energy consumption to maintain the operation of the system increased 4.93%. Taking the high energy loss with little rise of decolorization efficiency, 200 L/h is best choice for the system operation.