Effects of Extracellular Hydrolysis on the Production of Extracellular Polymeric Substances (EPS) and Soluble Microbial Products (SMPs) in Activated Sludge

摘要

Two identical aerobic laboratory-scale sequencing batch reactors were operated in parallel toinvestigate the effects of extracellular hydrolysis on the nature of activated sludge flocs, as well as theirproduction of EPS and SMPs. One of the reactors was fed with sodium acetate (soluble COD) and the otherwas fed with dry milk powder (particulate/colloidal COD). The results showed that extracellular hydrolysishad a significant effect on the settleability of the flocs. More diversified ecology and compactable flocs wereproduced by the reactor which was fed with particulate/colloidal COD. Substrate utilization patterns inactivated sludge were much related with the feed substrates. EPS matrix is the accommodation of extracellularenzyme, which enriched the protein content in the EPS. Extracellular hydrolysis process results in more EPSand SMPs.