Bioreactor

Trial with Eco System Plus ® in Sweden
By Mats Larsson, Sarrasso AB Nitrate From collected data we have established that the denitrification process has not been negatively affected. Thenitrification however is slower with ESP than without. As a whole the level of N03-N in the reference reactor increase from 5-7 (2mg/l) and in the ESP dosed reactor from 6,4-7,1 (1,5mg/I). The reaction rate withESP is more favorable during the decanting/sedimentation period. My conclusions are that this probably is because ESP increases micell formation and thereby increases the gas exchange causinganaerobic conditions to occur faster.

Phosphate The phosphorous levels measured during de nitrification increased approximately 40 % faster than in the reference reactor. You should note that the firstmeasurement was made 30 minutes into the treatment cycle. During the aerated part of treatment the level of phosphate in the reference reactor continue to rise for the first 60 minutes. Some of themeasured values are high and these affect the average so the correct value is probably slightly lower. During the decanting/sedimentation the reference value for 240 minutes was so low that we almostexpected that something happened. Further control of the values indicated that all values are low that no extremely low values cause the drop. My conclusion is that this is due to ESP's ability toincrease the amount of dissolved oxygen, which delays the increase in phosphate levels. But since the increase in the denitrification part of the cycle is 40%
© EcoCatalysts Pty Ltd 2004

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higherwith ESP this has little significance. Totally we have measured 25% lower total -Phosphorous levels in outgoing water based on daily averages. The levels in incoming 10mg/1 and outgoing O,19mg/1 beforeESP treatment and 0,14 mg/I with ESP.

COD With addition of ESP the measured COD is within a smaller interval (lower standard deviation) than without. Overall COD in outgoing water is lower with...