In this blog, we’ll explore the various types of sewage treatment microorganisms used today, their functions, and why wastewater treatment by microbes is an essential component of modern water management systems.

Why Use Microorganisms in Sewage Treatment?

Microorganisms—including bacteria, fungi, protozoa, and algae—are nature’s waste managers. In sewage treatment using microbes, these organisms consume organic matter (such as food waste, fats, oils, and other biodegradable substances) and convert it into simpler, non-toxic forms, including carbon dioxide, water, and biomass.

Benefits of wastewater treatment microorganisms include:

• Eco-friendly and cost-effective operation
  
• High efficiency in removing BOD (Biochemical Oxygen Demand) and COD (Chemical Oxygen Demand)
  
• Reduced use of harsh chemicals
  
• Ability to adapt to different types of waste streams

Key Types of Sewage Treatment Microorganisms

Here are the most commonly used microorganisms in wastewater treatment using bacteria and other microbes:

1. Aerobic Bacteria

Function: These bacteria require oxygen to survive and are widely used in activated sludge systems, trickling filters, and aerated lagoons.

How they work: Aerobic bacteria consume organic pollutants and convert them into carbon dioxide, water, and new microbial cells.

Common genera: Pseudomonas, Bacillus, Nitrosomonas

Applications:

• Municipal sewage treatment plants
  
• Food processing wastewater systems
  
• Sewage treatment by bacteria in aerobic digesters

2. Anaerobic Bacteria

Function: These bacteria thrive in oxygen-free environments and are commonly used in anaerobic digesters.

How they work: Anaerobic bacteria break down complex organic matter into methane, carbon dioxide, and stabilized sludge.

Common genera: Methanobacterium, Clostridium, Bacteroides

Applications:

• Sludge digestion
  
• Industrial wastewater treatment
  
• Biogas production from sewage

3. Facultative Bacteria

Function: These bacteria can survive in both aerobic and anaerobic conditions, making them versatile in varying treatment environments.

Common genera: Enterobacter, Escherichia

Applications:

• Oxidation ponds
  
• Septic tanks
  
• Transitional phases in multi-stage treatment systems

4. Nitrifying Bacteria

Function: Specialized bacteria involved in the nitrogen cycle that convert ammonia to nitrate, a critical step in nutrient removal.

How they work:

• Nitrosomonas converts ammonia (NH₃) to nitrite (NO₂⁻)
  
• Nitrobacter then converts nitrite to nitrate (NO₃⁻)

Applications:

• Wastewater treatment using bacteria in nitrification tanks
  
• Biological nutrient removal (BNR) systems
  
• Aquaculture and aquaponics wastewater management

5. Denitrifying Bacteria

Function: These bacteria convert nitrates into nitrogen gas, reducing nitrogen levels in treated water.

Common genera: Paracoccus, Pseudomonas

Applications:

• Final stages of nutrient removal
  
• Prevention of eutrophication in discharged effluents

6. Phosphorus-Accumulating Organisms (PAOs)

Function: These microbes absorb and store phosphorus more than their metabolic needs, helping to reduce phosphorus from wastewater.

Applications:

• Enhanced Biological Phosphorus Removal (EBPR) systems
  
• Sewage treatment plants with stringent discharge regulations

7. Protozoa

Function: These single-celled organisms consume bacteria and help maintain microbial balance in biological treatment systems.

Common types:

• Ciliates
  
• Flagellates
  
• Amoebae

Applications:

• Indicator organisms for sludge health
  
• Clarification stages in secondary treatment

8. Fungi and Algae (Limited Use)

Fungi can decompose complex organic matter in low-pH or low-nutrient environments, while algae are used in oxidation ponds to produce oxygen through photosynthesis.

Applications:

• Lagoon systems
  
• Specialized tertiary treatment processes
  
• Research-based bioremediation projects

Where Microbial Treatment is Applied?

• Municipal sewage systems across cities
  
• Textile and chemical industries, where microbes break down dyes and solvents
  
• Food and beverage industries, using high-organic load wastewater
  
• Slaughterhouses and breweries, with nutrient-rich effluents

Ion Exchange’s Advanced Sewage Treatment Solutions 

Ion Exchange is a leading provider of innovative water and wastewater treatment solutions globally.  Their advanced range of sewage treatment plants is designed to meet the diverse needs of the country’s growing population and industrial sectors. With a focus on sustainability and efficiency, Ion Exchange offers customized solutions that incorporate the latest technologies, ensuring optimal performance and environmental compliance.

INDION New Generation Packaged Sewage Treatment Plant (NGPSTP)

It is a state-of-the-art solution that combines the innovative technologies of lamella plate clarification and aeration, resulting in a highly efficient, ready-to-operate, prefabricated system for sewage treatment. This all-in-one single-tank packaged system is designed with a modular capacity ranging from 10 to 100 m3/d, making it both compact and user-friendly. Not only does it deliver high-quality effluent, but it also boasts features that cater to the specific needs of modern facilities. The NGPSTP’s advantages include minimal land usage, reduced power and chemical requirements, and low operating costs, making it an ideal choice for a wide range of applications while ensuring environmental sustainability and cost-effectiveness. 

INDION NGPSTP-NR 

It is an advanced sewage treatment solution that combines a fixed film reactor with lamella clarification, resulting in a high-performance, prefabricated system that is ready to operate. This all-in-one, modular design offers compact and simple operation with minimal maintenance. Built with an MS tank lined with FRP, it ensures no corrosion, delivering high-quality effluent while being efficient and easy to manage. 

Sequencing Batch Reactor (SBR) 

It is an advanced activated sludge process that operates in true batch mode, with both aeration and sludge settlement occurring within the same tank. Unlike conventional continuous-flow systems, which separate these functions into different spaces, the SBR performs them in a time sequence, offering greater flexibility. This design allows the SBR to handle varying influent volumes, making it adaptable to changing conditions, unlike the continuous system, which relies on a fixed flow rate. 

Advanced Fluidized Media Reactor (AFMR) system

It is a compact SINGLE TANK DESIGN UNIT that integrates an aeration tank with floating media, a lamella settler, and a chlorine contact tank. The AFMR media boasts a high surface area, excellent physical and chemical resistance, and minimal annual losses. INDION’s Advanced FMR offers significant advantages, including reduced space requirements, lower power consumption due to the elimination of sludge recirculation, and minimal maintenance thanks to its design without moving mechanical parts.

Future Trends in Microbial Wastewater Treatment

• Bioaugmentation: Adding selected microbial strains to boost treatment efficiency
  
• Genetically engineered bacteria for targeting specific pollutants
  
• Microbial fuel cells that generate electricity while treating wastewater
  
• Microbiome monitoring to assess treatment plant health in real-time

Conclusion

The use of sewage treatment microorganisms is at the heart of efficient and eco-friendly wastewater management. From sewage treatment by bacteria in large-scale municipal systems to wastewater treatment by microbes in industries, these microscopic organisms play a giant role in cleaning our water. Understanding the types of microbes involved helps in designing more effective and sustainable treatment systems for different types of waste.

Connect with Ion Exchange experts today for innovative, cost-effective, and customized solutions powered by nature’s purifiers—microorganisms.