Research Of Advanced Treatment Papermaking Wastewater And Piot System Of Photoelectrocatalytic And Heterogeneous Photocatalytic Composite Oxidation

Water pollution of papermaking industry is one of the major industrial pollutions, and has the features with the large emission, complicated compositions and high treatment difficulty. Sewage discharge of papermaking industry is difficult to meet the standard after treatment with traditional methods. Hence, it is necessary to use the advanced process. The photocatalytic oxidation technology has the mild reaction conditions, strong oxidation ability, no secondary pollution and wide application range, and has been paid more and more attention by the researches. But the photocatalytic efficiency is low due to the minority carrier recombination easily, and there have not been the reactor which can be applied in the industrial product. In order to solve these problems, this article introduced an adsorbed load photoelectrocatalytic and heterogeneous photocatalytic composite oxidation process, and developed a photoelectrocatalytic reactor which can be industrialized enlargemently, and a matched pilot system.The nano-Ti O2 adsorbed film was used as the photoelectrode, which was formed of the porous metal with the adsorption load of nano-Ti O2 colloid. In combination with heterogeneous photocatalytic system of nano-Ti O2 colloid, the combination of nano-Ti O2 adsorbed film photoelectrocatalytic system and heterogeneous photocatalyst, was applied to the advanced treatment of papermaking wastewater, The CODCr removal rate of papermaking wastewater was 93.6%, with good degradation efficiency of organic pollution components in the wastewater. The optimum process conditions were determined as follow: pretreatment with ternary composite flocculation system, 0.05%(w/w) of nano-Ti O2 photocatalyst, 2 m L/L H2O2, 0.5 g/L anhydrous sodium sulfate as the electrolyte,0.8 V bias voltage, aluminum honeycomb as photoelectrode materials which was connected with the anode of DC power.Base on the optimum process conditions of photoelectrocatalytic and heterogeneous photocatalytic composite oxidation papermaking wastewater, a composite reactor matched a pilot system was designed and built, which could be industrialized enlargement. The processing capacity of the system was 6 tons daily. Turquoise Blue and Rhodamine B were used as the simulation of organic pollutant in debugging of photoelectrocatalytic and heterogeneous photocatalytic composite oxidation pilot system, and obtained an excellent pilot production effect. Chroma and CODCr removal rate of Rhodamine B were 99.71% and 96.72%, respectively. The photoelectrocatalytic and heterogeneous photocatalytic composite oxidation pilot system has the features with reasonable layout, compact structure, can be industrialized enlargement, and has a very wide market prospect.