Existing municipal effluent treatment plants designed earlier for the BOD removal are usually not suitable for nitrification at low temperatures, because of
Small plant dimensions and low sludge age, respectively
of biokinetical reasons.
Consequences are in the cases of required nitrifications expensive plant extensions.
2. Our problem solution means the
Plant upgrading into fluidised bed reactors using microorganisms immobilised on adsorbing LEVAPOR-carrier.
Immobilising nitrifying bacteria on adsorbing carriers they
become more robust and efficient,
do produce lower quantities of excess sludge and
are able to maintain their activity even after a storage over 12 months.
Upgrading of a small municipal WWTP with aerated basin of 45 m³, for nitrification in winter, by filling it with 12 vol.% of LEVAPOR carrier
As a possible alternative to plant extension, it was considered to establish the nitrification by a susequent WWTP- upgrading via immobilisation of nitrifying sludge on 12 vol.% of adsorbing LEVAPOR-carrier.
Results: After addition into the basin the carrier cubes became colonised and fluidised directly and despite to low temperatures (November) the nitrification has been established at 17°C within two to three weeks and kept efficient, achieving 70 to 80% nitrification over several months, despite to lower temperatures in December (12 °C).
TKN-inlet- and NH4N-/NO3N-outlet concentrations during nitrification at 10 to 17°C by immobilised microorganisms.
Nitrification performance of the plant at different temperatures
immobilising of the activated sludge, nitrification has been established within 2 to 3 weeks
the nitrification remained stable and efficient even at lower temperatures, of 8 to 13°C and increased volumetric N-loading rates
the existing aeration system was proven as sufficient for a practically full fluidisation of the colonised carrier cubes.
removal of excess biomass from the surface of carrier cubes occurred automatically by fluidisation without any additive measure.
B. Nitrification and removal of hazardous pollutants from municipal effluents ( pilot plant tests)
Comparison of immobilised -LEVAPOR-carrier - vs. suspended sludge
Pilot plants In two parallel operated fluidised bed reactors, each of 3,1 m³, nitrification and hazardous pollutant removal of immobilised and suspended biomass have been compared. Additionally to higher degree of nitrification and denitrification ( due to inner pores of carrier cubes ), immobilised biomass achieved also a remarkably higher removal of polycondensed aromatic compounds.
Enhanced elimination of hazardous pollutants by biomass immobilised on adsorbing, porous carrier.
Raw water resources in Kafr El-Sheikh Governorate are affected by many contaminants particularly during the winter season and low demand period of the Nile River, in which water level decreases and organic matter increases resulting in decreased dissolved oxygen, and increased ammonia, nitrite and bacterial load in the water. In this study, physicochemical and microbiological characteristics of water samples taken seasonally from selected sampling sites on seven main canals in Kafr El-Sheikh Governorate were...
Environmental factors control the rate of nitrification. For a determined substrate concentration, the most significant environmental factors are temperature, pH and oxygen availability. The well known critical influence of those factors on the nitrification are here analyzed by making use of a specific software and advanced respirometry based on a dynamic LFS system, where the test conditions can be set in the corresponding test-settings board and their levels modified throughout the test performance....
For a determined substrate concentration, the most significant environmental factors are temperature, pH and oxygen availability. The well known critical influence of those factors on the nitrification are here analyzed by making use of a specific software and advanced respirometry based on a dynamic LFS system, where the test conditions can be set in the corresponding test-settings board and their levels modified throughout the test performance. In this way, it is possible to get and asses the trajectory of the...
The continuous measurements of N2O emissions from the aeration tanks of three activated sludge wastewater treatment plants (WWTPs) operated with biological nitrogen removal (BNR) and non-BNR were performed during the different operating conditions of several parameters, such as aeration, dissolved oxygen (DO) profiling and organic shock loading (with landfill leachate). The nitrification process is the main driving force behind N2O emission peaks. There are indications that the variation of the air flow rate...
Greener Waste Technology is a Process Engineering and Environmental Consultancy specialising in the Municipal sector. Following several years of extensive research Greener Waste Technology has advanced the unique bacteria dosing technology which has been successfully introduced to a number of water companies. The BioCube is being successfully used in wastewater treatment to optimise processes which suffer from excess FOG, BOD overload, poor nitrification, and poor sludge quality.