Influence of operating conditions for volatile fatty acids enrichment as a first step for polyhydroxyalkanoate production on a municipal waste water treatment plant.
This work describes the generation of volatile fatty acids (VFAs) as the first step of the polyhydroxyalkanoate (PHA) production cycle. Therefore four different substrates from a municipal waste water treatment plant (WWTP) were investigated regarding high VFA production and stable VFA composition. Due to its highest VFA yield primary sludge was used as substrate to test a series of operating conditions (temperature, pH, retention time (RT) and withdrawal (WD)) in order to find suitable conditions for a stable VFA production. The results demonstrated that although the substrate primary sludge differs in its consistence a stable composition of VFA could be achieved. Experiments with a semi-continuous reactor operation showed that a short RT of 4d and a small WD of 25% at pH=6 and around 30°C is preferable for high VFA mass flow (MF=1913 mg VFA/(Ld)) and a stable VFA composition.
University of Stuttgart, Institute for Sanitary Engineering, Water Quality and Solid Waste Management, Bandtaele 2, D-70569 Stuttgart, Germany. Electronic address: timo.pittmann@iswa.uni-stuttgart.de.
Timo
T
Pittmann
Heidrun
H
Steinmetz
D000143:Acids / Q000737:chemistry; D002947:Cities; D005232:Fatty Acids, Volatile / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D054813:Polyhydroxyalkanoates / Q000096:biosynthesis*; D013696:Temperature; D013997:Time Factors; D062065:Wastewater / Q000382:microbiology*; D018508:Water Purification
D000143:Acids; D005232:Fatty Acids, Volatile; D054813:Polyhydroxyalkanoates; D062065:Wastewater
Acidification; Biopolymer; Polyhydroxyalkanoates; Primary sludge; Volatile fatty acids