Page 17 - Simplified Wastewater Treatment Fundamentals_BNR
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Biological Nutrient Reduction (BNR)
In Summary, nitrogen reducing bacteria needs include:
✓ Food: Ammonia (NH3) Nitrite (NO2) and Nitrate (NO3)
✓ F/M of 0.2 to 0.06
✓ Dissolved Oxygen
✓ Contact Time
✓ pH 6.8 to 7.5
✓ Alkalinity 7.14 pounds/pound of Ammonia
✓ Temperature (at least 12 degrees Celsius)
✓ 6 to 20 days (or more, depending on temperature) SRT
It is important to note that in colder climates the nitrification process has difficulty surviving. As a result,
wastewater facilities in colder climates may not require ammonia removal in the fall and winter seasons.
