The effect of fermentation products on enhanced biological phosphorus removal, polyphosphate storage, and microbial population dynamics

Abstract

Using anaerobic/aerobic sequencing batch reactors (SBRs) it was found that pre-fermentation of influent glucose resulted in a microbial population capable of enhanced biological phosphorus removal (EBPR). Batch tests indicated the C1-C5 carboxylic acids, except propionate, typically improved phosphorus removal. Branched molecules were superior to their linear isomers. The C1-C5 alcohols did not affect removal. Glucose, propionate, and an amino-acid rich substrate were detrimental. Using NMR spectroscopy it was observed that intracellular forms and locations of phosphorus did not change regardless of the substrate received. Polyphosphate (polyP) was present throughout the cells at the end of aerobiosis. It then degraded to inorganic phosphate via a zero-order enzymatic reaction concentrated at the cell membrane. An anaerobic/aerobic SBR receiving starch, rather than glucose fermentation products, showed only marginal EBPR and did not respond to carboxylic acids or other substrates in batch tests. Pseudomonas and Bacillus were numerous in the glucose system but were not isolated from the starch system. Aeromonas were dominant in the starch system. Although the glucose system showed better phosphorus removal than the starch system, it also showed greater variability. Phosphorus removal varied in a chaotic, but bounded, manner, probably due to population dynamics.

Research Advances and Challenges in the Microbiology of Enhanced Biological Phosphorus Removal—A Critical Review

“…Hartman (1990, 1993) were the first to suggest that glucose could enhance GAO proliferation and impede EBPR. Others have reported similar results (Akin and Ugurlu, 2001;Randall et al, 1994). However, a wide range of studies have documented glucose-induced phosphorus removal when glucose was used as the sole carbon substrate, though the process stability sometimes was low (Carucci et al, 1994(Carucci et al, , 1995Jeon and Park, 2000;Jeon et al, 2001;Kumar and Chaudhari, 2003;N.…”

“…While carbon availability in the form of readily biodegradable COD or VFAs is critical for successful EBPR, carbon type also appears to be important, particularly relative to process stability. Contradicting earlier studies indicating that propionate was detrimental to EBPR systems (Hood and Randall, 2001;Randall et al, 1994), recent studies have shown that the addition of propionate, or switching between propionate and acetate on a short-term basis, impeded GAO proliferation in EBPR systems (H. Oehmen et al, 2004;Oehmen, Yuan, Blackall, and Keller, 2005). The PAOs (e.g., Accumulibacter) appear to take up both propionate and acetate rapidly with no specific preference, while Competibacter and a-proteobacterial GAOs take up and acclimate to propionate slowly and exhibit a low preference for acetate.…”

Sequencing Batch Reactor for Wastewater Treatment: Recent Advances

“…A higher COD-tophosphorus ratio (mg/mg) such as above 40 in raw water help achieve low effluent phosphorus concentration and high process stability in full-scale plants [24]. The form of the COD is also a crucial factor for selection of PAOs.…”

Prefermentación de agua residual urbana empleando un reactor biopelícula de lecho sumergido

“…Diversos estudios indican una mejora del proceso de EBF cuando se trabaja con materia orgánica compuesta por sustratos fermentados (Rabinowitz y Oldham, 1986;Randall et al, 1994;Marais et al, 1983). Como generalmente el contenido de ácidos grasos volátiles (AGV) de las aguas residuales urbanas es muy bajo o nulo, diversos estudios recomiendan realizar la pre-fermentación del agua residual a depurar, de forma que se incorporen al afluente del proceso de EBF, la concentración de AGV apropiada en cada caso (Skalsky y Daigger, 1995;Randall et al, 1994;Abu-ghararah y Randall, 1991;Lilley, et al, 1990;Elefsiniotis y Oldham 1991;Arun et al, 1988).…”

“…Como generalmente el contenido de ácidos grasos volátiles (AGV) de las aguas residuales urbanas es muy bajo o nulo, diversos estudios recomiendan realizar la pre-fermentación del agua residual a depurar, de forma que se incorporen al afluente del proceso de EBF, la concentración de AGV apropiada en cada caso (Skalsky y Daigger, 1995;Randall et al, 1994;Abu-ghararah y Randall, 1991;Lilley, et al, 1990;Elefsiniotis y Oldham 1991;Arun et al, 1988). Sedlak (1991) indica que para eliminar 1 mg/l de fósforo se necesitan de 7-9 mg/l de AGV.…”