Improvement of carbon usage for phosphorus recovery in EBPR-r and the shift in microbial community.

Enhanced biological phosphorus removal and recovery (EBPR-r) is a biofilm process that makes use of polyphosphate accumulating organisms (PAOs) to remove and recover phosphorus (P) from wastewater. The original process was inefficient, as indicated by the low P-release to carbon (C)-uptake (P/C) molar ratio of the biofilm. This study successfully validated a strategy to improve the P/C ratio by at least 3-fold.

Simultaneous phosphorus uptake and denitrification by EBPR-r biofilm under aerobic conditions: effect of dissolved oxygen.

A biofilm process, termed enhanced biological phosphorus removal and recovery (EBPR-r), was recently developed as a post-denitrification approach to facilitate phosphorus (P) recovery from wastewater. Although simultaneous P uptake and denitrification was achieved despite substantial intrusion of dissolved oxygen (DO >6 mg/L), to what extent DO affects the process was unclear. Hence, in this study a series of batch experiments was conducted to assess the activity of the biofilm under various DO concentrations.

A direct pre-screen for marine bacteria producing compounds inhibiting quorum sensing reveals diverse planktonic bacteria that are bioactive.

A promising new strategy in antibacterial research is inhibition of the bacterial communication system termed quorum sensing. In this study, a novel and rapid pre-screening method was developed to detect the production of chemical inhibitors of this system (quorum-quenching compounds) by bacteria isolated from marine and estuarine waters. This method involves direct screening of mixed populations on an agar plate, facilitating specific isolation of bioactive colonies.

Enrichment of anodophilic nitrogen fixing bacteria in a bioelectrochemical system.

We demonstrated the ability of a bio-anode to fix dinitrogen (N2), and confirmed that diazotrophs can be used to treat N-deficient wastewater in a bioelectrochemical system (BES). A two-compartment BES was fed with an N-deficient medium containing glucose for >200 days. The average glucose and COD removal at an anodic potential of +200 mV vs.

A novel post denitrification configuration for phosphorus recovery using polyphosphate accumulating organisms.

Enhanced biological phosphorus removal (EBPR) has been widely used to remove phosphorus (P) from wastewater. In this study we report a novel modification to the EBPR approach, namely enhanced biological phosphorus removal and recovery (EBPR-r) that facilitates biological recovery of P from wastewater using a post denitrification configuration. The novel approach consists of two major steps.

Comparison of microbial communities in pilot-scale bioreactors treating Bayer liquor organic wastes.

Western Australian bauxite deposits are naturally associated with high amounts of humic and fulvic materials that co-digest during Bayer processing. Sodium oxalate remains soluble and can co-precipitate with aluminium hydroxide unless it is removed. Removal of sodium oxalate requires a secondary crystallisation step followed by storage.