What is the importance of Waste Activated Sludge and Return Activated Sludge in the secondary treatment of wastewater?
The purpose of Return Activated Sludge (RAS) is to prevent loss of microorganisms from the aeration tank and maintain an adequate population for treatment of the wastewater. As microbes metabolize their substrate, they grow and multiply in number. To prevent overpopulation of microorganisms in the aeration tank, part of the sludge that is equivalent to the microbial growth (or yield) is taken out of the system as Waste Activated Sludge (WAS).
hello.
return activated sludge for notification and denitrification
return activated sludge for the removal of 90% of nitrogen and 10% of phosphorus.
The purpose of both RAS and WAS aptly explained by @Mohamed Hasnain Isa.
To reiterate, RAS is needed to progress with the aeration digestion process.
WAS is the excess micro organisms( more than that is needed ) This matter is removed and may be gainfully used in another process viz.composting cured of bio-mass, Etc.
A balance is maintained in all the anaerobic and aerobic processes of a treatment system .
Well wishes for nature's process.
I agree Mohamed Hasnain Isa " The purpose of Return Activated Sludge (RAS) is to prevent loss of microorganisms from the aeration tank and maintain an adequate population for treatment of the wastewater. As microbes metabolize their substrate, they grow and multiply in number. To prevent overpopulation of microorganisms in the aeration tank, part of the sludge that is equivalent to the microbial growth (or yield) is taken out of the system as Waste Activated Sludge (WAS)".
agree with Isa & omar's answer with a point to identify thin line in between based on MLVSS in sludge...
I apologize in advance for being so rude, but let me say with all the possible sympathy that questions like this (and several others) cannot properly labelled as "research".
Any basic textbook of Sanitary Engineering necessarily explains what "sludge" is, and how biological sludge must be handled.
Why struggling to do research work out of our expertise, in fields that for others are ordinary and fully understood and established?
RAS prevents the microorganism detoriation from aeration tank to facilitate better wastewater treatment since microorganisms contribute for substrate metabolizing. WAS prevents the overpopulation of such microorganisms.
- Badges
- Science topic
- Similar topics
- Correction