In order to study the effect of different carbon sources on the phosphorus release

PHA transform

population of the phosphate accumulating organisms(PAOs)

and the anaerobic stoichiometry of PHA and glycogen

three enhanced biological phosphorus removal(EBPR)reactors were operated for a long term in the sequencing batch reactor(SBR)fed with acetate/propionate

glucose

or domestic wastewater.The result showed that three systems acquired stable phosphorus removal efficiency from the 182nd day

and FISH results showed that PAOs accounted for 89%?3%

55%?3%

45%?4% of total biomass.Polyhydroxybutyrate and polyhydroxyvalerate were synthesized by PAOs when fed with acetate

glucose

or domestic wastewater as carbon source

only polyhydroxyvalerate was synthesized when fed with propionate as carbon source

and no poly-3-hydroxy-2- methylvalerate(PH2MV)was detected.Stoichiometry research showed that 1.15 C-mol of PHB and 0.15 C-mol of PHV were synthesized per C-mol acetate

meanwhile 0.47 C-mol of glycogen was degraded.0.44 C-mol of PHV was synthesized and 0.271 C-mol of glycogen was degraded when fed with 1 C-mol propionate.0.16 C-mol of PHV was synthesized and 0.16 C-mol of glycogen was degraded when fed with one C-mol glucose

while very few of PHB was synthesized during this process.The proportions of PHB/COD and PHV/COD were 0.98 and 0.13 respectively when fed with domestic wastewater.Release of phosphorus reached the maximum 134 mg稬-1 and release rate was 23.80 mg P?(g VSS)-1穐-1 with acetate as sole carbon source.With propionate or glucose as carbon source

phosphorus release rate was similar

while with domestic wastewater as carbon source phosphorus release rate was the smallest.