Contrast of volatile fatty acid driven and inorganic acid or base driven phosphorus release and uptake in enhanced biological phosphorus removal.
Addition of an inorganic acid or base was detrimental to net phosphorus removals in short-term batch experiments, suggesting there might be system upset when pH changes. In contrast, addition of volatile fatty acids (VFAs) increased anaerobic phosphorus release and aerobic phosphorus uptake while maintaining or improving net phosphorus removals. The effect of pH change differed if the acid or base added was inorganic versus organic. Volatile fatty acids that resulted in poly-3-hydroxy-butyrate rather than poly-3-hydroxy-valerate resulted in greater net phosphorus removals, and this corresponded to differences in consumption of reducing equivalents. Acetic acid resulted in improved net phosphorus removal compared to sodium acetate, suggesting that acid forms of VFAs might be superior as supplemental VFAs. It is hypothesized that anaerobic phosphorus release following addition of inorganic acid is primarily a result of phosphorus and proton (H+) symport (excretion from the cell) for pH homeostasis, whereas addition of VFAs results in phosphorus and H+ release to maintain the proton motive force.
Department of Civil, Environmental, and Construction Engineering, University of Central Florida, P.O. Box 162450, Orlando, FL 32816, USA. firstname.lastname@example.org
SourceWater environment research : a research publication of the Water Environment Federation 84:4 2012 Apr pg 305-12
Fatty Acids, Volatile
Pub Type(s)Journal Article
Research Support, U.S. Gov't, Non-P.H.S.