炼化企业中水紫外线消毒及其影响因素简

研究水质对254 nm紫外线透射率的影响,通过动态实验考察了照射时间、254 nm紫外线透射率以及紫外线剂量对炼化企业中水消毒效果的影响并同时考察异养菌、硫酸盐还原菌和铁细菌的光复活及暗修复现象。结果表明,有机物是影响炼化企业中水紫外线消毒的重要因素;紫外线对炼化企业中水中的异养菌具有良好的灭活作用;增加照射时间对消毒效果的提升作用受254 nm紫外线透射率的影响;紫外线透射率在较低的范围内时对消毒效果的影响相对较大,在较高的范围内时影响较小;紫外线剂量-响应曲线受254 nm紫外线透射率的影响;剂量的“成分”,即照射时间和透射率的不同组合,也会对消毒效果产生影响;在80 mJ/cm²的剂量下,20 h内异养菌出现了较强烈的光复活和暗修复现象,铁细菌仅出现了明显的光复活现象,硫酸盐还原菌没有表现出明显的复活。

UV disinfection of reclaimed water from an oil refining and petrochemical enterprise and its influencing factors

The effects of water quality parameters on UV transmittance at 254 nm were investigated. The impacts of irradiation time, UV transmittance at 254 nm and UV dose on disinfection efficiency of reclaimed water from an oil refining and petrochemical enterprise were examined using a continuous flow UV system. Meanwhile, photo-reactivation and dark repair of heterotrophic bacteria, sulfate reducing bacteria and iron bacteria were studied. The results indicated that organic matter was a significant factor influencing UV disinfection of reclaimed water from oil refining and petrochemical enterprises. UV disinfection was efficient for inactivating heterotrophic bacteria in actual reclaimed water. The elevating effect of increasing irradiation time on log inactivation was influenced by UV transmittance at 254 nm. The impact of UV transmittance on disinfection efficiency was relatively strong when UV transmittance was in lower range, while the impact was weaker when UV transmittance was in higher range. The dose-response curve was also influenced by UV transmittance at 254 nm. The "constituent" of UV dose, which could be interpreted as different combinations of irradiation time and UV transmittance, was a factor affecting inactivation efficiency. After an UV dose of 80 mJ/cm² was applied, heterotrophic bacteria demonstrated relatively strong photo-reactivation and dark repair in 20 h while only significant photo-reactivation was observed for iron bacteria; sulfate reducing bacteria did not show any detectable repair in 20 h.