Biological Nitrogen Removal Database

A manually curated data resource for microbial nitrogen removal

Freshwater systems

Experimental setup

Influent:Aquaculture wastewater

Denitrification system:Recirculating aquaculture systems Heterotrophic Denitrification

Denitrifying reactor:Self cleaning Inherent gas Denitrification reactor (SID-reactor)-Modified moving bed biofilm reactor

Medium:HDPE biocarrier Stöhr HXF12KLL

Culture taken from:Activated sludge

Organism (s) cultured:Pike perch (Sander lucioperca)


Electron donor:Methanol

Electron acceptor:Nitrate

Experimental Information

Input NO3-N (mg/l):26.0

Nitrate removal rate (mg NO3-N/l/h):nan

Denitrification rate (gNO3-N removed/m3/day):450.0

Microorganisms identified:nan

Molecular tools:nan

Information about Article

Major findings:Continuous denitrification was achieved as a result of the modfied MBBR. In this commercial recirculation aquaculture systems (RAS)clogging was prevented by recirculation of Inherent gas into the reactor.

Authors:Müller-Belecke et al., 2013

Title:The “self cleaning inherent gas denitrification-reactor” for nitrate elimination in RAS for pike perch (Sander lucioperca) production

Pubmed link:None

Full research link:Link

Abstract:Denitrification reactors have proven their functionality in commercial recirculation aquaculture systems (RAS). Nevertheless, clogging occurs due to the low hydraulic loads necessary to accomplish anoxic conditions for a successful denitrification process in RAS, which hampers the adjustment of stable working conditions within fixed bed denitrification reactors. Reactors working on the basis of activated sludge demand careful hydraulic control and/or complex configurations for sludge retention. To develop a low-maintenance denitrification reactor, an enclosed moving bed filter, driven by recirculation of the inherent, oxygen poor gas was designed. A Self cleaning Inherent gas Denitrification reactor (SID-reactor) of 0.65 m3, which offered a moving bed volume of 0.39 m3 was connected with a RAS of semi-industrial scale for pike perch (Sander lucioperca) production. This species indicates suboptimal environmental conditions (as e.g. NO3-N concentrations above approximately 68 mg l?1) by prompt reduction of the feed intake. In different experimental series, the SID-reactor was operated with denatured ethanol, methanol, acetic acid or glycerin as carbon sources and changing operational modes. Clogging was prevented by a 40 second inherent gas recirculation twice an hour, which provided continuous, maintenance free operation with marginal energy demand. With inlet (RAS) and outlet NO3-N concentrations in the range of 49 mg l?1 and 12 mg l?1, mean denitrification rates of 199 g to 235 g NO3-N per m3 moving bed volume and day were determined for all tested carbon sources. Negative effects on the feed intake of the reared pike perch were detected with all carbon sources except methanol. Changing the mode of operation to continuous circulation of the filter bed at inlet NO3-N concentrations of 26 mg l?1, the denitrification performance reached 451 g NO3-N per m3 moving bed volume and day. The SID-reactor allowed for the reduction of freshwater exchange in the pike perch RAS from 600 l to 70 l (?88%) and the sodium bicarbonate buffer from 182 g to 31 g (?83%) per kg of administered food. The easy and reliable operation of the SID-reactor could help to establish controlled denitrification as a routine purification step in RAS