Solar Energy, Vol.170, 323-335, 2018
TiO2 water-bell photoreactor for wastewater treatment
In spite of the intense academic research that has been conducted on the possibility of mineralization of a vast range of water pollutants using TiO2 photocatalysis, the scale up to industrial scale and commercialization of TiO2 photocatalysis treatment systems is still very limited. The design of a photocatalytic reactor that is simple, energy efficient, less expensive to build and operate is crucial for the development and widespread of TiO2 photocatalysis. A solar photocatalytic reactor is designed and constructed. The reactor is based on generating a thin water film to allow for solar light penetration and continuous oxygenation. Recirculating the reaction solution at a high flow rate ensure good mixing and avoid dead zones in the photoreactor. Reactor performance for degradation of phenol, as a model compound, was evaluated using aeroxide P25. Factors affecting the degradation efficiency were studied including catalyst loading, light intensity, initial pollutant concentration, oxidant addition and exposure time. Dissolved oxygen levels, temperature and pH were monitored through all the conducted tests. The water-bell photoreactor performance was compared with other photoreactors using benchmarks: the degradation rate constant and the reactor throughput. The photoreactor is promising for scale-up and commercialization owing to its modular design, an integrated storage, simple and cheap components that are not susceptible to breakage and optical losses.