TY - JOUR
T1 - Effect of high nitrate concentration on PHB storage in sequencing batch reactor under anoxic conditions
AU - Çiǧgin, Asli S.
AU - Karahan, Özlem
AU - Orhon, Derin
PY - 2009/2
Y1 - 2009/2
N2 - The study investigated effect of high influent nitrate concentration on poly-β-hydroxybutyrate, (PHB), storage in a sequencing batch reactor, (SBR), under anoxic conditions. Acetate was fed as pulse during anoxic phase, sustained with external nitrate feeding. SBR operation involved three runs at steady state with COD/N ratios of 3.84, 2.93 and 1.54 gCOD/gN, where external nitrate concentrations gradually increased from 50 mg N/l to 114 mg N/l and 226 mg N/l, in 1st, 2nd and 3rd runs, respectively. In 1st run, acetate was fully converted into PHB with the storage yield value of 0.57-0.59 gCOD/gCOD, calculated both in terms of PHB formation and NOX utilization, confirming storage was the sole substrate utilization mechanism. In the following runs, PHB formation was reduced and the storage yield based on PHB dropped down to 0.40 and 0.33 gCOD/gCOD with increasing influent nitrate concentrations, indicating that higher portions of acetate were diverted to simultaneous direct growth. The observations suggested that nitrite accumulation detected at low COD/N ratios was responsible for inhibition of PHB storage.
AB - The study investigated effect of high influent nitrate concentration on poly-β-hydroxybutyrate, (PHB), storage in a sequencing batch reactor, (SBR), under anoxic conditions. Acetate was fed as pulse during anoxic phase, sustained with external nitrate feeding. SBR operation involved three runs at steady state with COD/N ratios of 3.84, 2.93 and 1.54 gCOD/gN, where external nitrate concentrations gradually increased from 50 mg N/l to 114 mg N/l and 226 mg N/l, in 1st, 2nd and 3rd runs, respectively. In 1st run, acetate was fully converted into PHB with the storage yield value of 0.57-0.59 gCOD/gCOD, calculated both in terms of PHB formation and NOX utilization, confirming storage was the sole substrate utilization mechanism. In the following runs, PHB formation was reduced and the storage yield based on PHB dropped down to 0.40 and 0.33 gCOD/gCOD with increasing influent nitrate concentrations, indicating that higher portions of acetate were diverted to simultaneous direct growth. The observations suggested that nitrite accumulation detected at low COD/N ratios was responsible for inhibition of PHB storage.
KW - Acetate
KW - Anoxic conditions
KW - Denitrification potential
KW - Sequencing batch reactor
KW - Substrate storage
UR - http://www.scopus.com/inward/record.url?scp=55549143971&partnerID=8YFLogxK
U2 - 10.1016/j.biortech.2008.08.036
DO - 10.1016/j.biortech.2008.08.036
M3 - Article
C2 - 18842401
AN - SCOPUS:55549143971
SN - 0960-8524
VL - 100
SP - 1376
EP - 1382
JO - Bioresource Technology
JF - Bioresource Technology
IS - 3
ER -