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Title: Effects of anaerobic HRT and VFA loading on the kinetics and stoichiometry of enhanced biological phosphorus removal
Abstract Enhanced biological phosphorus removal (EBPR) can recover significant quantities of wastewater phosphorus. However, this resource recovery process realizes limited use largely due to process stability concerns. The research evaluated the effects of anaerobic HRT (τAN) and VFA concentration—critical operational parameters that can be externally controlled—on EBPR performance. Evaluated alone, τAN(1–4 h) exhibited no statistical effect on effluent phosphorus. However, PHA increased with VFA loading and biomass accumulated more phosphorus. Regarding resiliency, under increasing VFA loads PAOs hydrolyzed more phosphorus to uptake/catabolize VFAs; moreover, PHA synthesis normalized to VFA loading increased with τAN, suggesting fermentation. Kinetically, PAOs exhibited a Monod‐like relationships for qPHAANand qVFAANas a function of anaerobic P release; additionally, qPAEexhibited a Monod‐like relationship with end‐anaerobic PHA concentration. A culminating analysis affirmed the relationship between enhanced aerobic P uptake, and net P removal, with a parameter (phosphorus removal propensity factor) that combines influent VFA concentration with τAN. Practitioner pointsEvaluated alone τANexhibits no statistical effect on effluent phosphorus in an EBPR configuration.Increased PHA synthesis, associated with increased VFAs and/or extended τAN,enhances aerobic phosphorus removal.PHA synthesis normalized to VFA loading increased with τAN, suggesting fermentation in the EBPR anaerobic zone.Aerobic phosphorus uptake increases linearly with anaerobic phosphorus release, with the slope exceeding unity.Increased VFAs can be substituted for shorter anaerobic HRTs, and vice versa, to enhance EBPR performance.  more » « less
Award ID(s):
1705728
PAR ID:
10449798
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Water Environment Research
Volume:
93
Issue:
9
ISSN:
1061-4303
Page Range / eLocation ID:
p. 1608-1618
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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