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 NO3Nitrosomonas Nitrobacter
fish toxic at
tish toxic at
> 0,5 mg/L
at 50 mg/L
Pathways and fish toxicities of inorganic nitrogen
Test plant and mode of operation
Test plant : Biofilter with V = L volume, each filled with
Biocarrier : PE carrier 780 m²/m³ , LEVAPOR >20.000 m²/m³
PU foam 1500 m²/m³ , Keramzit 400 m²/m³
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.
Removal of ammoniacal nitrogen by PE vs. LEVAPOR carrier over a week
• 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. m²/m³
Bulk weight: 30 kg/m³ - Water binding capacity ~100 kg/m³
Wetting: within few hours – Biofilm generation: 120 min.
Specialty: high content of powdered activated
enables unique effects, not only simple cell adhesion