How many types of anaerobic secondary wastewater treatment processes?
Many industrial effluent streams, including those from the agricultural, food and beverage, dairy, pulp and paper, textile, and sewage treatment industries, are treated using anaerobic wastewater treatment.
In streams with significant levels of organic matter, anaerobic technologies are frequently used prior to aerobic treatment, which are measured as high BOD, COD, or TSS.
In this blog, we will discuss about? the various anaerobic secondary wastewater treatment processes!
1: Anaerobic Lagoons
Anaerobic lagoons are enormous man-made ponds with a surface area of 1-2 acres, and a depth of up to 20 feet. They are widely employed for the first stage of municipal wastewater treatment, as well as the treatment of various industrial wastewater streams and agricultural wastewater from the production of meat.
Working of anaerobic lagoons
The wastewater is often sent to the lagoon's bottom, where it settles to form an upper liquid layer and a semi-solid sludge layer.
Anaerobic digestion may be able to break down the organic components in the wastewater, because the liquid layer prevents oxygen from reaching the sludge layer. The process could take as less as a few weeks or as much as six months, to restore the desired range of BOD/COD values.
Maintaining optimal conditions would improve the rate of anaerobic microbe activity, leading to a shorter wastewater detention time, because anaerobic bacteria like specific environmental characteristics, such as warm water temperatures (85-95° F) and close to neutral pH.
The rate of anaerobic respiration can also be slowed down by a number of factors, including as variations in BOD/COD concentration and the presence of substances like salt, potassium, calcium, and magnesium.
2: Sludge blanket reactors
Anaerobic treatment devices called sludge blanket reactors circulate wastewater, over a free-floating "blanket" of suspended sludge particles.
When they breakdown the organic materials in the wastewater, anaerobes in the sludge develop into larger granules, which settle to the bottom of the reactor tank and may be recycled for further cycles.
The unit's cleaned effluent awakens and leaves. Collecting hoods gather the biogases generated by the degradation process, throughout the treatment cycle.
Anaerobic sludge blanket reactors are available in several configurations, including:
- Upflow anaerobic sludge blankets (UASBs): Wastewater is treated with UASB by being pumped downward into a UASB bioreactor. The wastewater floats as it passes through the sludge blanket.
- Expanded granular sludge beds (EGSBs): The key distinction between EGSB and UASB technology is that the wastewater is recirculated through the system, to promote greater contact between the sludge and the wastewater. Moreover, they often have higher-velocity influent flows and are taller than UASBs. EGSBs can therefore handle streams with higher organic loads than UASB systems.
- Anaerobic baffled reactors (ABRs): Alternating baffles divide the semi-enclosed chambers that make up an ABR. The baffles cause the wastewater stream, which normally flows smoothly from the reactor entry to the outflow, to come into closer contact with the sludge blanket.
3: Anaerobic filter reactors
A reactor tank and a type of fixed filter material make up anaerobic filter reactors. It is permitted for anaerobic bacteria to populate the filter medium and form a biofilm.
The filter medium, which also has enough surface area to expose anaerobes in the biofilm to the organic compounds in the stream, catches particles from the wastewater stream as it passes through it throughout treatment cycles.
The filter media will eventually become clogged with too much biofilm and particle accumulation, requiring maintenance measures like backwashing and cleaning to maintain maximum efficiency. The performance of the filter reactor must be constantly checked over time.
Manufacturer of wastewater treatment plants
Netsol Water is the leading manufacturer of water treatment and sewage treatment systems in India. We offer water softeners, wastewater treatment facilities, including those that use anaerobic wastewater treatment techniques, sewage treatment plants, water treatment plants, RO plants, and effluent treatment plants for use in a variety of industries.
The most difficult water treatment or wastewater treatment requirements of a wide range of clients, including small businesses, companies, and regional government agencies, are handled by Netsol by combining cutting-edge technology with years of experience.
For further information, contact us at +91 9650608473 or email at enquiry@netsolwater.com