The potential of producing heterotrophic bacteria biomass on aquaculture waste.
The effluent from the drumfilter of a recirculation aquaculture system was used as substrate to produce heterotrophic bacteria in suspended growth reactors. The effects of organic carbon supplementation (0, 3, 6, 8 g/l sodium acetate) and of hydraulic retention times (11-1h) on bacteria biomass production and nutrient conversion were investigated. Bacteria production, expressed as volatile suspended solids (VSS), was enhanced by organic carbon supplementation, resulting in a production of 55-125 g VSS/kg fish feed (0.2-0.5 g VSS/g carbon). Maximum observed crude protein production was approximately 100 g protein/kg fish feed. The metabolic maintenance costs were 0.08 Cmol/Cmol h, and the maximum growth rate was 0.25-0.5 h(-1). Ninety percent of the inorganic nitrogenous and 80% of ortho-phosphate were converted. Producing bacteria on the drumfilter effluent results in additional protein retention and lowers overall nutrient discharge from recirculation aquaculture systems.
Schneider
Oliver
O
Aquaculture and Fisheries Group, Wageningen University, P.O. Box 338, 6700 AH Wageningen, The Netherlands.
Sereti
Vasiliki
V
Machiels
Marcel A M
MA
Eding
Ep H
EH
Verreth
Johan A J
JA
D000818:Animals; D017756:Aquaculture / Q000295:instrumentation / Q000379:methods*; D001419:Bacteria / Q000378:metabolism*; D018533:Biomass; D019149:Bioreactors / Q000382:microbiology*; D005399:Fishes; D052836:Heterotrophic Processes; D013379:Substrate Specificity; D014865:Waste Disposal, Fluid / Q000295:instrumentation / Q000379:methods*; D014873:Water Pollutants / Q000378:metabolism*
D014873:Water Pollutants