nitrification-denitrification

sanitation engineering

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July 1, 2026

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Nitrification-denitrification is a two-step biological process used in wastewater treatment to remove nitrogen, a plant nutrient that can cause eutrophication in receiving waters.1

The first step, nitrification, is carried out by nitrifying bacteria. These microorganisms convert ammonia, which is toxic to fish and exerts an oxygen demand, into nitrites and then into nitrates.21

The second step, denitrification, is performed by denitrifying bacteria. These bacteria convert the nitrates into nitrogen gas, which is then released into the atmosphere. This process is crucial for preventing the accumulation of nitrogen in oceans and depleting soil fertility. While essential for the natural nitrogen cycle, its application in wastewater treatment requires additional tanks and increases costs.341

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wastewater treatment
Removal of plant nutrients
A method called nitrification-denitrification can be used to remove the nitrates. It is a two-step biological process in which ammonia nitrogen is first converted into nitrates by microorganisms. The nitrates are further metabolized by another species of bacteria, forming nitrogen gas that escapes into the air. This process…
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A method called nitrification-denitrification can be used to remove the nitrates. It is a two-step biological process in which ammonia nitrogen is first converted into nitrates by microorganisms. The nitrates are further metabolized by another species of bacteria, forming nitrogen gas that escapes into the air. This process…
Read More