The Importance of Nitrogen in Wastewater Treatment and Its Environmental Impact

The importance of nitrogen goes hand in hand with its ill effects on the environment and organisms specifically humans as the heavy accumulation of the same in water bodies leads to hazardous effects such as eutrophication having direct impact on human health.

The major contributors to this nitrogen accumulation in water bodies are industries in the form of ammoniacal nitrogen. The pollution control bodies such as NGT and CPCB are very stringent about the ammoniacal nitrogen discharge through the effluent.

What is Nitrification and Denitrification in Wastewater Treatment?

Understanding Nitrification

Nitrification is a two-step aerobic process where ammonia (NH3) is converted into nitrate (NO3) through the action of specialized bacteria. This process occurs naturally in soil and water but is crucial in wastewater treatment to prevent ammonia toxicity and eutrophication in aquatic environments.

1. Ammonia Oxidation: The first step involves the conversion of ammonia to nitrite (NO2) by ammonia-oxidizing bacteria (AOB) such as Nitrosomonas.

NH3 ​+O2  ​→ NO2+ 3H+ + 2e

2. Nitrite Oxidation: The second step involves the conversion of nitrite to nitrate by nitrite-oxidizing bacteria (NOB) such as Nitrobacter.

NO2 ​ + 1/2​O2​ → NO3

Understanding Denitrification

Denitrification is an anaerobic process where nitrate is reduced to nitrogen gas (N2), which is then released into the atmosphere. This process helps in the removal of excess nitrogen from wastewater, thus preventing nutrient pollution.

  1. Nitrate Reduction: Nitrate is first reduced to nitrite.

NO3 ​→ NO2

  1. Nitrite Reduction: Nitrite is further reduced to nitric oxide (NO), nitrous oxide (N2O), and finally nitrogen gas.

NO2​ → NO → N2​O → N2

 The Role of Bioremediation in Wastewater Treatment:

Bioremediation leverages natural or engineered biological processes to degrade pollutants. In the context of nitrification and denitrification, bioremediation uses microbial communities to enhance nitrogen removal efficiently.

  1. Bioaugmentation: This involves the addition of specific strains of nitrifying and denitrifying bacteria to wastewater treatment systems. These microorganisms are selected for their efficiency in nitrogen transformation processes.
  • Nitrosomonas europaea and Nitrobacter winogradskyi are common bioaugmentation agents for nitrification.
  • Pseudomonas and Paracoccus species are effective for denitrification.
  1. Biostimulation: This approach involves optimizing the environmental conditions to favor the growth and activity of indigenous nitrifying and denitrifying bacteria. Parameters such as pH, temperature, oxygen levels, and nutrient availability are carefully controlled.
  2. Immobilization Techniques: Microorganisms can be immobilized on various carriers such as activated carbon, biochar, or synthetic polymers to enhance their stability and activity. This method can significantly improve the efficiency of nitrification and denitrification processes by providing a conducive environment for microbial growth and activity.

Ammoniacal nitrogen control highly depends on the microbes responsible for nitrification and denitrification as well as dissolved oxygen. While in the case of industries specific anoxic systems are designed to control the ammonia in the effluent.

 Anoxic Systems in Wastewater Treatment?

The anoxic system is designed to follow the nitrifying and denitrifying process.

  1. Nitrifying Tank: – It consists of an oxygen source specifically aerators to induce dissolved oxygen in the effluent, which nitrifying bacteria utilize to convert ammonia to nitrite.
  2. Denitrifying Tank: – This tank is devoid of any oxygen sources to induce denitrification where nitrite turns into nitrate with the help of denitrifying bacteria.
  1. Canal or Stream: – Here the wastewater is allowed to flow through a canal or a stream uniformly which allows the nitrogen gas to escape which is ultimately the degradation of bacteria.

The anoxic system is ideally amalgamated with popular and prominent wastewater treatment types to achieve the eradication of NH3-N. By understanding and implementing these processes, industries can significantly reduce their impact on the environment and comply with stringent regulations on ammoniacal nitrogen discharge.

Curious to know more? Get a FREE sample of our bio cultures for effluent treatment or schedule a 1:1 consultation with our technical experts.

Transforming wastewater treatment in paper manufacturing industries: Replacing Ammonium Phosphate and Phosphoric Acid with T1B MacMi

Introduction:  

The Integrated Paper and Pulp Industry is a leading paper manufacturing company involved in pulping of raw materials and paper manufacturing. The company is currently located in Dahej, Gujarat. With a strong commitment to environmental sustainability, The Integrated paper and pulp industry operates an industrial wastewater treatment plant (WWTP) to treat the effluent generated during its production processes.

They were using very high amounts of Ammonium Sulphate and Phosphoric Acid to meet their nutritional requirements and maintain MLVSS. To address these challenges, the industry implemented a bioaugmentation program at its WWTP, which resulted in significant improvements in the treatment process and compliance with regulatory standards.

Details provided for Effluent Treatment Plant (ETP):

The industry had primary treatment, biological treatment, and then a tertiary treatment.

Flow    4500-6000 KLD
Type of process ASP
No. of aeration tanks 7 (in series)
Capacity of aeration tanks 100 KL (1 and 2 ), 400 KL(3), 1800 KL(4,5,6,7)
Total RT 31.2 hours

Findings and Challenges:

Parameters Inlet parameters Outlet parameters
COD 3,000 to 5,000 800 to 500
BOD 1000 to 1800 400 to 150
MLVSS (avg.) 6500 5679

To maintain the performance of the ETP, especially the biological tank the MLVSS levels are necessary to be maintained. However, it required a very high amount of ammonium sulphate and phosphoric acid viz. 700 kgs and 300 kgs per day respectively. Such a huge amount imposed a very high cost as well as the chemical consumption had high chance of going on with unwanted reactions in ETP, especially with lignin streams.

The Approach:

The industry partnered with us looking for a common solution that can serve as a replacement for Ammonium Sulphate and Phosphoric acid that can reduce the cost and should be Organic. Our team of experts went through the complete past 3 months’ data of ETP to analyze the trends. After conducting the visit, Team One Biotech suggested implementing T1B MacMi for wastewater treatment.

 The Solution: T1B MacMi

  • Organic, plant-based bio cultures replace conventional nitrogen and phosphorus sources.
  • Eliminate the need for urea, DAP, ammonium sulphate, phosphoric acid, and other chemicals.
  • Single source of Nitrogen, Phosphorous, Potash, Calcium, Magnesium, Copper, and other micro and macronutrients.
  • Promote biological wastewater treatment through specialized microorganisms.

Results:

The implementation of the bioaugmentation program resulted in significant improvements in the performance of biological units in their WWTP:

  • 98% reduction in ammonium sulphate and phosphoric acid consumption
  • Maintained MLVSS levels within desired ranges
  • 60% reduction in nutrient costs and 30% reduction in overall operating expenses (OPEX)

Are you facing similar challenges in industrial wastewater treatment? Explore the potential of T1B MacMi and connect with our technical experts today:

+91 8855050575 / sales@teamonebiotech.com

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