The effect of substrate on the composition of polyhydroxyalkanoates in enhanced biological phosphorus removal


Yagci N., COKGOR E. U., Artan N., RANDALL C., ORHON D.

JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY, cilt.82, sa.3, ss.295-303, 2007 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 82 Sayı: 3
  • Basım Tarihi: 2007
  • Doi Numarası: 10.1002/jctb.1672
  • Dergi Adı: JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.295-303
  • Anahtar Kelimeler: acetate, enhanced biological phosphorus removal, glycogen, polyhydroxyalkanoates, process stoichiometry, propionate, GLYCOGEN-ACCUMULATING ORGANISMS, ANAEROBIC METABOLISM, ACETATE UPTAKE, MIXED CULTURE, POLYPHOSPHATE, PHOSPHATE, COMPETITION, MODEL, PROPIONATE, BACTERIA
  • İstanbul Teknik Üniversitesi Adresli: Evet

Özet

This paper primarily evaluates the effect of external substrate type on the composition of polyhydroxyalkanoates in enhanced biological phosphorus removal (EBPR). Two sets of sequencing batch reactors (SBRs) are operated for this purpose, one with acetate and the other with propionate as the sole carbon source at different influent COD/phosphate ratios in the range 6.7-20 mgCOD mg(-1) P. Results indicate that propionate is a more efficient substrate for EBPR, enabling total phosphate removal regardless of the change in COD/phosphate ratio. Total polyhydroxyalkanoates formation of 267-291 mgCOD L-1 with a slight increase at higher influent phosphorus levels is observed for acetate experiments, and a slightly lower level of 2S0-280mgCOD L-1, with a similar trend for propionate experiments. The volatile fatty acid type and composition in the influent induces a significant difference in the polyhydroxyalkanoates composition of the two sets of activated sludge sustained in corresponding SBR systems. Propionate is mostly stored as 3-hydroxy-2-methylvalerate and polyhydroxyvalerate, while acetate is stored as polyhydroxybutyrate. The P uptake rate in SBRs fed with propionate is considerably higher than that in the acetate reactors. Parallel batch experiments yield different results, especially for systems fed with acetate, indicating that the enzymatic system to metabolize propionate is not rapidly established, always yielding a dominant polyhydroxybutyrate fraction in the generated polyhydroxyalkanoates regardless of the level of propionate in the feed. (c) 2007 Society of Chemical Industry