Selection and performanceof biocarriers for aquacultureswith water reuse Christoph GreckiWR IKRA DABIEPoland

The fish hatchery and farm WR Dabie, Poland

Targets of the investigations

to improve the efficiency of the water recycle plant via increased nutrient removal, meaning to find a more efficient biocarrier for the removal of fish toxic compounds,than existing plastic carriers

to define the biokinetic parameter of the N-removal

to develop an optimized technology for the N-removal.

NH3/NH4 NO2 NO3

NitrosomonasNitrobacterfish toxic at >1,0 mg/Ltish toxic at> 0,5 mg/Lnon toxicat 50 mg/LPathways and fish toxicities of inorganic nitrogen compoundsN2denitrification

Test plant and mode of operationTest plant : Biofilter with V = L volume, each filled with biocarrier

Biocarrier : PE carrier 780 m/m , LEVAPOR >20.000 m/m PU foam 1500 m/m , Keramzit 400 m/m

Mode of operation : a filtered and aerated streams of the recycle water were forwarded through the non colonized carrier layers at xy sec retention time.

Sampling and analyses : grab samples were analysed twice in a week, NH4, NO2 and NO3 were determined.

The biofilter pilot plants

PE-carrier LEVAPOR PU foam Ceramics780 m/m > 20.000 m/m 1.500 m/m 400 m/m

inletRemoval of ammoniacal nitrogen by PE vs. LEVAPOR carrier over a week

CONCLUSIONS

In all tests LEVAPOR carrier have achieved highest degree of removal both for ammoniacal as well as for nitrite nitrogen

The LEVAPOR supported nitrification achieved a ca. 100 % higher efficiency than the PE carrier supported biofilter

Due to high porosity and carrier surface, the LEVAPOR supported reactor has achieved a remarkable NO2-removal

The LEVAPOR supported biofilter removed 300% more (NH4+NO2)N than the PE carrier supported filter

On basis of the achieved results the company has decided to apply LEVAPOR biocarrier in the new biofilters.

LEVAPOR biocarrier have been designed in labs.

Dimensions: 20x20x7 mm Surface : 1,34 mio. m/mBulk weight: 30 kg/m - Water binding capacity ~100 kg/mWetting: within few hours Biofilm generation: 120 min.

Specialty: high content of powdered activated carbon enables unique effects, not only simple cell adhesion .Effects: Adsorption of inhibitors lower toxicity in bioreactor faster bioprocess start stable process

Scheme of a biofilter using biocarriers

The new biofilter to be filled with LEVAPOR