Article

Study on the flocs poly-β-hydroxybutyrate production and process optimization in the bio-flocs technology system

Department of Environmental Engineering, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310029, China.
Bioresource Technology (Impact Factor: 5.04). 08/2011; 102(16):7599-602. DOI: 10.1016/j.biortech.2011.05.028
Source: PubMed

ABSTRACT The bio-flocs technology (BFT) was applied in the sequencing batch reactor (SBR) to treat aquaculture wastewater for flocs poly-β-hydroxybutyrate (PHB) accumulation with alternant anaerobic and aerobic conditions. The statistical modeling approach was used to evaluate system performance and to optimize the flocs PHB yield at batch mode. The results show that all variables have significant impact on the response objective, as well as the interactions of the C/N ratio with the flocs biomass concentration (VSS) and anaerobic time, respectively. By process optimization, approximately 150-200 PHB/VSS (mg·g) of flocs PHB yield was achieved in the range of 4-7g/l of flocs biomass concentration, 15-18 of the C/N ratio and 50-85min of anaerobic time in the BFT systems. The results demonstrated that a suitable flocs PHB yield can be obtained via optimizing the ex-situ operating strategy, which have potential prebiotic value and practical implication for the sustainable aquaculture.

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    • "BFT system has been reported that the yield and accumulation of poly-␤hydroxybutyrate (PHB) under intermittent aeration are greater than those under continuous aeration (CA), where an aeration process involving a 0.5-h aeration/0.5-h non-aeration intermittent cycle has been proven to be the best (Liu et al., 2011; Ruan et al., 2011). For BFT used in the biological treatment of municipal and industrial wastewaters, studies have primarily focused on the physical properties of flocs that contribute to hindering flocs' settling and compactability (Nguyen et al., 2008). "
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