Nitrification Principle / Field Trials of Nitrification Efficiency
Nitrifying bioreactors are activated with consortia of nitrifiers by immobilizing them on an inert substratum designed as cartridge. They grow as biofilm and as water passes over nitrification is effected. The consortia consist of diverse flora of autotrophic nitrifiers as presented in the figures below.
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| NsV 443 (Nitrosospira sp.) | Nitrifiers inside cysts | NIT2 (Nitrobacter sp.) |
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| Ntspa 712 (Phylum Nitrospira) | Cells having intracytoplasmic membranes and carboxysomes characteristic to the autotrophic nitrifiers | NmV (Nitrosococcus mobilis linneage) |
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| DAPI stained consortia | Diversity of the cells in the consortia | EUB 338 (Bacteria) |
The nitrifiers function on Monod principle and have the capability to enhance activity with increase in the total ammonia-nitrogen loading as illustrated in the figure below. The outgoing ammonia concentration and NO 2 -N is maintained below 0.1 ppm even when the incoming ammonia concentration exceeds 0.5 ppm.
*Field level validations have been conducted in live hatcheries and the results are summarized below.
Nitrification in a broodstock maintenance system connected to Packed Bed Bioreactor
- System is operated without water exchange
- Ammonia-nitrogen and nitrite-nitrogen concentrations consistently remain at an average level of 0.3ppm and does not exceed 0.6ppm.
- Nitrate concentration does not increase beyond 7ppm due to denitrification, which has been experimentally established as one of the characteristics of the consortia.
- Consequently the technology eliminates the requirement of introducing a distinct denitrifying system to facilitate nitrate removal.
- Precisely there is total removal of nitrogen from the Recirculating Aquaculture System.
Activation of PBBR integrated to Penaeus monodon maturation system – Duration required for activation
Within seven days the reactor could be made fully functional.
TAN, NO 2 -N and NO3-N in an experimental Penaeus monodon brood stock maintenance system during quarantine integrated with SBSBR
Figure showing the utility of the SBSBR in Brood Stock quarantine system.