How many pounds of dissolved oxygen are required to convert one pound of ammonia?

The correct answer indicates that 4.6 pounds of dissolved oxygen are required to convert one pound of ammonia (NH3) into nitrate (NO3), following the nitrification process. This process involves the oxidation of ammonia – first by ammonia-oxidizing bacteria to form nitrite (NO2), and then by nitrite-oxidizing bacteria to convert nitrite into nitrate.

Understanding the stoichiometry of this biochemical process helps clarify the oxygen demand associated with the conversion of ammonia. Nitrification is an aerobic process that relies heavily on oxygen. The conversion of one mole of ammonia requires a specific number of moles of dissolved oxygen, where it's established that approximately 4.6 pounds of oxygen are necessary for the complete aerobic oxidation of one pound of ammonia.

This relationship is crucial for wastewater treatment operations, as it influences the design and management of aeration systems in treatment facilities. Efficient management of oxygen levels can directly impact the effectiveness of ammonia removal and overall water quality. This concept is foundational in wastewater treatment, particularly in processes that aim to mitigate nitrogen compounds.