This example in connection with our previous post,
How to calculate Aeration Tank Volume?
Total BOD to be removed (Influent) = 250 mg/l (assume) x 1400 = 350 kg/Day (we consider 1400 M3/Day Effluent Plant)
Hence O2 to be transferred =350 kg/Day
Method of Aeration = Fine Bubble Diffuser
SOTE (Standard O2 Transfer Efficiency For 300 mm disc type diffuser submergence) =20%
Hence O2 required 350/0.20 =1750 kg/day.
Assuming alpha Factor (Ratio of SOTE in clean water to effluent water)=0.8 and
Another alpha Factor (Factor for fouling of diffusers) =0.8
Oxygen requirement =2734 kg/day {Oxygen % in the atmospheric air = 23.2%}
Hence, Air Requirement =11790 kg/day {With Sp.gravity of Air at 50°C =0.8 kg/M³}
Air requirement = 14737 M³/Day = 614 M³/Hr
Allowing 5% extra, So 650 M³/Hr @ 0.5 kg/cm2 blower can be select
further note below points too.,
one more point to be consider the Depth of aeration Tank, suppose it is 4 metre depth select 0.5 or 0.6 kg/cm² in blower side.
View Comments (77)
Thank Sir.
Excellent . Informative,
The info is very useful . For my clarification, in Air requirement of aeration tank topic
Total BOD to be removed = 250 (assume) x 1400 = 350 kg/Day; What does 1400 denotes?
And for more details to know can you provide me the contact mail id. since I work in STP concern I like to know more about Calculation and process details from your website.
Thank you,
1400 m3/day effluent to be treated
Hence O2 required 350/0.20 =1750 kg/day.
Oxygen requirement =2734 kg/day {Oxygen % in the atmospheric air = 23.2%}
What is it?
1400 m3 is effulent flow / day
What is 1400 in this calculation
effluent load 1400 m3/day taken to account.
Can you Please explain these calculations in detail
now, check it again the post has been updated, thanks to drop the commands
khud hi samajh le na be. kyun dass raha hai yar dassan kha le lassan
Total BOD to be removed = 250 (assume) x 1400 = 350 kg/Day
what is 1400?
thanks your point out - 1400 we consider as effluent qty in m3/day
Nice Post!! Really helpful.
Can you tell me roughly SOTE % for a tubular fine bubble (say 600 mm to 1000mm) & Disc Type Coarse Bubble(80mm, 150mm)?
Is there any thumb rule for calculating it?
waiting for your reply
How to find out this value? - explain
Oxygen requirement =2734 kg/day
Hence, Air Requirement =11790 kg/day
2734 kg/day /23.2% (Oxygen % in the atmospheric air = 23.2%) = 11784 kg/day air
Plant capacity
1400 assuming plant capacity
yes, this is plant capacity in example case we taken into account.
Nice information sir.thanks
Nice information sir.thanks but finally what is volume of aeration tanks??
Sir what is 250 in this calculation
250 is mg/l of effluent BOD (assume)
Pls sir explain this calculation in detail