Method and apparatus for processing manure

Method for processing manure, liquid manure and/or Kjeldahl-N containing waste water being subjected to a nitrification in an aerated nitrification reactor (9) which contains active sludge rich in nitrifying bacteria being used in the nitirification reactor (9) if necessary and to a denitrification in a high rate recirculation denitrification reactor (13) which contains a very compact biomass which is capable of converting nitrate to nitrogen gas and to which an organic substrate is supplied obtained from the denitrification step in the nitrification reactor (9), characterized in that the loading of the nitrification reactor (9) is controlled to obtain an optimal nitrification and denitrification on the basis of one or more of the following data;

• the incoming nitrogen load;
• the information from a WAZU respiration meter (not shown);
• the oxygen concentration in the nitrification reactor (9);
• the pH value in the nitrification reactor (9), the criterion for which is that the pH value is in the range limited by 6 and 8.5;
• the amount of air required
• the residence time
• the temperature in both the nitrification reactor (9) and the recirculation denitrification reactor (13) is kept below 40.degree. C.;
• the concentration of oxidized nitrogen in the influent for the recirculation denitrification reactor (13), the criterion for which is that the concentration is between 0 and 4 g N/1;
• the concentration of oxidized nitrogen in the nitrification reactor (9), the criterion for which in the sludge/liquid mixture in the nitrification reactor is that the concentration is between 0 and 4 g N/1;
• the concentration of the carbon source in the effluent from the recirculation denitrification reactor (13);
• the gas production in the recirculation denitrification reactor (13)
• the effluent from the nitrification reactor (9) partially being passed to the recirculation dentrification reactor (13), adding a source of carbon to the effluent to be passed to the recirculation denitrification reactor (13) and passing another portion of the effluent stream from the nitrification reactor (9) to a separation step (19) to separate a sludge, mixture in the nitrification reactor is that the concentration is between 0 and 4 g N/1;
• the concentration of the carbon source in the effluent from the recirculation denitrification reactor (13);
• the gas production in the recirculation denitrification reactor (13)
• the effluent from the nitrification reactor (9) partially being passed to the recirculation denitrification reactor (13), adding a source of carbon to the effluent to be passed to the recirculation denitrification reactor (13) and passing another portion of the effluent stream from the nitrification reactor (9) to a separation step (19) to separate a sludge, the effluent from separation step (19) being passed to a discharge line denitrification reactor (37) under the addition of a carbon source if desired, the discharge line denitrification reactor (37) being provided with means for an effluent discharge (38) and a nitrogen discharge (17).