Search results for " Nitrification"
showing 5 items of 15 documents
Effect of C/N shock variation on the performances of a moving bed membrane bioreactor.
2015
Abstract The effect of a sharp variation of C/N ratio in a moving bed membrane bioreactor (MB-MBR) pilot plant treating high strength wastewater has been investigated. The experimental campaign was divided into two periods, each characterized by a different C/N ratio (namely, 2.5 and 15, Period 1 and Period 2, respectively). The MB-MBR system was analyzed in terms of organic carbon removal, nitrification efficiency, biokinetic activity and fouling behavior. The results showed that the nitrification process was severely affected by lower C/N value and by high concentration of ammonia. It was noticed an extensive stress effect on the autotrophic bacteria. Furthermore, it was observed an incre…
A mass balance evaluation of the ecological significance of historical nitrogen fluxes in Lake Kinneret
2010
Comparison between kinetics of autochthonous marine bacteria in activated sludge and granular sludge systems at different salinity and SRTs.
2019
Biological nutrient removal performances and kinetics of autochthonous marine biomass in forms of activated sludge and aerobic granular sludge were investigated under different salinity and sludge retention time (SRT). Both the biomasses, cultivated from a fish-canning wastewater, were subjected to stepwise increases in salinity (+2 gNaCl L−1), from 30 gNaCl L−1 up to 50 gNaCl L−1 with the aim to evaluate the maximum potential in withstanding salinity by the autochthonous marine biomass. Microbial marine species belonging to the genus of Cryomorphaceae and of Rhodobacteraceae were found dominant in both the systems at the maximum salinity tested (50 gNaCl L−1). The organic carbon was remove…
Influence of operative conditions in a hybrid activated sludge/biofilm process for the treatment of municipal wastewater in a cold climate region: a …
2012
In the last years the idea to combine suspended and attached bomass by introducing suspended carriers into the aeration tank for biofilm attachment and growth was proposed. The increase of the overall sludge age in the system leads to a favourable environment for the growth of nitrifying bacteria, so that nitrification may be maintained throughout the winter. The main aim of the study was to investigate a hybrid MBBR process, mostly in terms of nitrification, when operating with different values of the sludge retention time (SRT), and highlighting the influence of temperature on the process. Based on experience in practice it was hypothesized that nitrification could be maintained at far lo…
MUNICIPAL WASTEWATER TREATMENT IN A HYBRID ACTIVATED SLUDGE BIOFILM REACTOR: A PILOT PLANT EXPERIENCE
2008
A hybrid activated sludge/biofilm process (IFAS) was investigated. This process which contains both suspended and attached biomass, is created by introducing plastic elements as biofilm carriers material into a classical activated sludge system. This process is suitable for upgrading existing activated sludge wastewater treatment plants which are no longer able to comply with the effluent standards, and in particular in those cases where the existing plant does not nitrify or only nitrify during summer. However, the IFAS processes are relatively new and there are still uncertainties with respect to their design. A main task is to find a rational approach to the design of nitrification in hy…