Sludge reduction performance and bacterial community dynamics in a pilot-scale multi-stage digester system with prolonged sludge retention time were characterized. Throughout the operation period of 281 days, the total loading sludge and the total digested sludge were 4700 and 3300 kg-MLSS. After 114 days of operation, the residual MLSS (RMLSS) in the reactors for sludge treatment was maintained at 18-25 kg-RMLSS m-3, and the sludge reduction efficiency achieved 95% under the F/M ratio (kg-loading MLSS kg-RMLSS-1) of less than 0.018. Also, among the sludge components, both fixed suspended solids and volatile suspended solids were reduced. Based on the sludge reduction performance and the RNA-based bacterial community characteristics, the combined action of the maintenance metabolism, lysis-cryptic growth, and particulate inorganic matter is proposed as the sludge reduction mechanism in the multi-stage sludge treatment process.

中文翻译：

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中试规模多级消化池系统中污泥减少和细菌群落动态的表征，污泥保留时间延长。

在中试规模的多级消化器系统中，污泥的减少性能和细菌群落动态具有较长的污泥滞留时间。在整个281天的运行期间，总污泥和消化后的污泥分别为4700和3300 kg-MLSS。运行114天后，污泥处理反应器中的残留MLSS（RMLSS）保持在18-25 kg-RMLSS m-3，并且在F / M比下（公斤载MLSS）污泥减少效率达到95％。 kg-RMLSS-1）小于0.018。而且，在污泥成分中，固定的悬浮固体和挥发性的悬浮固体都减少了。基于污泥的减少性能和基于RNA的细菌群落特征，维持新陈代谢，裂解-隐性生长，