茶多酚作为辅助消毒剂的饮用水生物稳定性研究

STUDY ON BIOLOGICAL STABILITY OF TEA POLYPHENOL AS SECONDARY DISINFECTANT IN DRINKING WATER

茶多酚具有消毒能力,可作为一种饮用水辅助消毒剂,但消毒后水中细菌再生长规律尚不清晰。对茶多酚投入水中后的水质进行监测分析,发现可能是茶多酚和菌体蛋白质结合生成了生物可降解有机物(BDOC),成为管网水中异养菌增长的动力,从而使管网水的生物稳定性随着消毒接触时间的延长而降低。试验结果表明,茶多酚在水中的衰减速率和BDOC生成速率有较好相关性。辅助消毒剂投入水中6 h内茶多酚浓度衰减很快,消毒效率指数较低,随着时间的延长,茶多酚浓度降低,消毒效率指数随之提高。因此,茶多酚作为辅助消毒剂时,建议其投加方式不宜采用一次投加,而应连续投加。采用连续投加的方式可以降低茶多酚的衰减速率,提高出水的生物稳定性。

Tea polyphenols has disinfection ability which can be used as an auxiliary disinfectant for drinking water.But the law of bacteria growth is not clear after disinfecting.Water quality monitoring for the tea polyphenols added in the water showed that tea polyphenols combined with bacterial protein might generate biodegradable dissolved organic carbon（BDOC）which became the driving force for the growth of heterotrophic bacteria in pipe network water,thus the biological stability of the pipe water decreased with the prolonging of the contact time of disinfection.Results showed that the decay rate of tea polyphenols in water correlated well with the BDOC formation rate.The concentration of tea polyphenols was rapidly decreased in the 6 hours after the auxiliary disinfectant added into the water and the disinfection efficiency index was lower.As the time went on,the concentration of tea polyphenols decreased,and the disinfection efficiency index increased.Consequently,tea polyphenols as an auxiliary disinfectant should not be added once,but should be added sequentially.The adding method can reduce the decay rate of tea polyphenols and improve drinking water biological stability.