Ozonation of the return activated sludge (AS) flow is an emerging option for excess-sludge reduction. This study aimed to evaluate the potential changes suffered by some kinetic parameters of the activated sludge models (ASMs) in the combined ozone-AS process. The heterotrophic maximum specific growth rate (μ_Hmax) was determined by respirometry in three model-sludges (S1 to S3) treated in batch with different O₃ doses. S1 was a fresh synthetic biosolid composed by only two particulate fractions. S2 was a digestate of S1 almost made by the endogenous residues. S3 was from a municipal wastewater treatment plant. μ_Hmax increased significantly from 3.5 d^-1 originally, to more than 10 d^-1 in the ozonated sludges. Ozonation promoted the selection of fast-growing bacteria in the activated sludges, after transitory inactivation and long lag times. Some microorganisms survived to 3 months of digestion and subsequent ozonation, and then regrow faster than before, once fed again with acetate. The research is of interest from the point of view of the application of the ASM models to the ozone-AS process, but also for wastewater disinfection in general.

中文翻译：

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臭氧化活性污泥中的细菌失活和再生长

回流活性污泥（AS）流的臭氧化是减少过量污泥的一种新兴选择。这项研究旨在评估臭氧-AS组合工艺中活性污泥模型（ASM）的某些动力学参数遭受的潜在变化。通过呼吸测定法测定了三种不同的O ₃剂量分批处理的模型污泥（S1至S3）的异养最大比生长速率（_μHmax ）。S1是仅由两个颗粒部分组成的新鲜合成生物固体。S2是几乎由内源性残基组成的S1的消化物。S3来自市政废水处理厂。μ _HMAX从3.5 d显著增加^-1最初，以超过10 d ^-1在臭氧污泥中。经过短暂的灭活和较长的滞后时间后，臭氧化促进了活性污泥中快速生长细菌的选择。一些微生物可以存活到3个月的消化和随后的臭氧化作用，然后再生长，比以前更快，再次用乙酸盐喂养。从将ASM模型应用于臭氧-AS过程以及一般用于废水消毒的观点来看，该研究是有意义的。