Nutrients – Balance is the Key

Nutrients are a critical consideration for long term and effective wastewater treatment. Having a balance of nutrients is extremely important in order to protect receiving waters. Too much nutrients? No good. Too little nutrients? No good! Striking a balance is the key to success, allowing companies to maintain compliance and protect the environment.

Too many nutrients:

Macronutrients, including nitrogen and phosphorus compounds are essential for biological health and development. These nutrients are often out of balance when it comes to wastewater constituents. Excessive nutrients not removed during treatment will harm the body of water the wastewater is discharged into. The ongoing effluent discharge of nutrients will lead to a deterioration of receiving waters, excessive algal growth and potential eutrophication in fresh and saltwater bodies.

Too little nutrients:

A lack of nutrients will inhibit the treatment system biology and degrade the effluent quality. Additionally, biological deficiencies in treatment plants result in noncompliant effluent as well as a proliferation of nuisance organisms that complicate plant operations and aesthetics. Industrial waste streams are commonly lacking essential nutrients and therefor they are added into the wastewater to allow efficient biological treatment.

Nutrient compounds of concern for municipal and industrial wastewater treatment:  

• Ammonia (NH3-N) – toxic to aquatic life in low concentrations, typically removed via biological nitrification; however, can be removed using ammonia stripping, breakpoint chlorination or membrane filtration.
• Nitrite (NO2-N) – intermediate byproduct of biological nitrification. May accumulate as a “nitrite lock” during system acclimation or toxic events, causing issues with treatment plant operations.
• Nitrate (NO3-N) – terminal product of biological nitrification. In excess, is toxic and may be fatal to aquatic life, cattle and humans. Nitrate binds with iron in the red blood cells so that it can no longer bind oxygen. Nitrate is typically removed via biological denitrification; however, can be removed using ion exchange or membrane filtration.
• Ortho-phosphate (PO4-P) – the most abundant form of phosphorus found in wastewater. Excess phosphate contained in treatment plant effluent can ultimately lead to eutrophication of fresh surface water bodies. Phosphorus is typically removed via chemical precipitation or biological phosphorus removal; however, can be removed using ion exchange or membrane filtration.

Photographed below:

bioprocessH2O’s bioPULSE Airlift MBR System Installation:

A combination of chemical precipitation using ferric chloride as the coagulant, biological treatment and membrane filtration to achieve BOD, ammonia and phosphorus removal from a cheese facility’s wastewater stream.

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