非均相光催化水处理管式反应器的放大设计

Scale-up and design of a multi-phase multitubular photoreactor for wastewater treatment

研究了非均相光催化反应器在放大过程中光辐射能衰减和流体返混对其放大过程设计的影响。结果表明,光辐射能随着光源和反应管的中心距的增加急剧衰减,两者呈1 56次方反比关系;管式反应器中流体的返混程度远小于相同反应体积的环型反应器,这有利于提高水中有机污染物的降解率。建立了一套由3组管式反应器串联且光接触面与光源的距离小于10cm的连续光催化水处理中试装置,并对印染废水进行处理。化学需氧量可从150～180mg/L降至50mg/L以下,处理量为50L/h时的出水优于国家一级排放标准。

The influences of the backmixing degree in photocatalytic reactors and the decay of radiant energy on the enlarged design of the photoreactor were studied. The results show that the distance between the lamp and the interface irradiated by UV light is required to be less than 10 cm since the radiant energy decreases remarkably with the distance in the inverse ratio of 1.56. Compared with annular reactors, the degradation efficiency of the organic compounds in water in multitubular photocatalytic reactors is higher owing to the smaller backmixing degree. The multi-phase water-treatment equipment composed of three multitubular photocatalytic reactors was designed to dispose the dying wastewater, and the chemical oxygen demand (COD) value can be reduced from 150-180 mg/L to less than 50 mg/L. The outlet water after treated is superior in quality to the first-grade norm of the national standard.