Biological wastewater treatment is a very effective and common treatment step in many industrial and municipal wastewater facilities.
Harnessing the power of bacterial and other micro-organisms, biological wastewater treatment is an economic way to breakdown organic contaminants from a wide variety of wastewater streams.
Biological Wastewater Treatment Technologies are a critical component in many wastewater treatment systems. These systems are an effective tool to breakdown organic material and other pollutants to help organizations meet discharge permit requirements and reduce sewer surcharges.
Anaerobic Wastewater Treatment
Anaerobic wastewater treatment processes use bacteria to breakdown BOD (Biological Oxygen Demand), COD (Chemical Oxygen Demand), and other organic contaminants with the absence of oxygen. Anaerobic systems do not require the addition of air to the reactors, which lowers energy costs to operate the system. In many instances, anaerobic digestion systems can be energy positive. Anaerobic systems are also able to treat wastewater that has higher concentrations of BOD/COD.
During the anaerobic digestion process, the bacteria create biogas as a by-product that can be harvested and utilized in an electrical generator or boiler. Anaerobic digestion also generally produces lower amounts of sludge, when compared to aerobic systems.
Common Anaerobic Systems:
- High Rate - Granular Anaerobic Digestion (UASB - Upflow Anaerobic Sludge Bed & EGSB - Expanded Granular Sludge Bed)
- Medium Rate - Anaerobic MBR (Membrane Bio Reactors)
- Low Rate - CSTR (Continuously Stirred Tank Reactor)
Aerobic Wastewater Treatment
Aerobic wastewater treatment systems include the addition of air (oxygen) within the wastewater reactor. These systems are effective in reducing BOD/COD to very low levels. In many, cases aerobic systems are used in conjunction with anaerobic systems to polish wastewater streams to remove nutrients or polish prior to discharge. These systems are also very resilient to variations in temperature and can effectively be used in almost any climate. Also, these systems can be installed in series or combined together to increase treatment capacity.
Common Aerobic Systems
- MBBR (Moving Bed Biofilm Reactors)
- Activated Sludge
- Aerobic MBR (Membrane Bioreactors)
- Sequencing Batch Reactors
- Oxidation Ditches
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