原水深度处理过程中的生物稳定性和分子量分布

Biological stability and molecular weight distribution during advanced water treatment processes of source water

研究了水源水在'预臭氧+常规+主臭氧/生物活性炭'深度处理工艺流程净化中的各工艺段出水有机物及分子量的变化特征,建立了生物稳定性与有机物分子量的关系,实现了对深度处理后供水水质生物稳定性的评估。研究结果表明:预臭氧可将大分子的天然有机物分解为相对分子质量小于1000的有机物,并提高水的可生化性;导致常规处理工艺去除水中有机物的效率降低;主臭氧可将有机物进一步氧化,并将部分氧化成相对分子质量小于500的有机物;生物活性炭可提高出水的生物稳定性,但对相对分子质量小于1000的有机物去除有限;分子量越小生物稳定性越差,越不容易被去除。此研究结果为评估水源水质深度处理的生物稳定性提供了理论依据。

The variation characteristics of molecular weight（MW）and organic matters in the effluent were studied,respectively sampling from each unit of the advanced water treatment processes,preozonation,conventional water treatment（CWT）,and main ozonation/BAC（biological activated carbon）.The relationship was established between biological stability and MW of organic matters,and the evaluation was realized for the biological stability of the drinking water quality from advanced water treatment.Results showed that the natural organic matters with high MW in raw water could be oxidized into that with MW less than 1000 by the preozonation process,and the biodegradability of raw water was improved.The CWT process has brought about rate lower in organic matters removal.Effluent organic matters from the CWT process were furthermore decomposed by the main ozonation process,and some organic matters were oxidized into the ones with MW less than 500.The biological stability of the effluent was increased by BAC process,but the removal rate of organic matters with MW less than 1000 was lower.The smaller MW and the worse biological stability of organic matters were,the more difficult theywere removed.These finds provided a theoretical basis for evaluation on biological stability of source water fromadvanced water treat ment processes.