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.
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?
we want to discuss on the topic of aeration settling.
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
how to calculate 350mg/d o2
Hi Sir,
Thank you for your valuable knowlege.
You have mention that Sp.gravity of Air at 50°C =0.8 kg/M³ , but this value is about 1.05 kg/M³
This will change the Air requirements,
Regards,
Dnyaneshwar
If aeration tank death is 5 metre then what capacity blower require and why?
Does the submergence SOTE vary with the depth ?
i have mechanical areator , make gsd ar 511 model what its oxygen transfer rate
How come oxygen required-2734 kg/d,
How much O2 required for Per kg of BOD.
Plz elaborate.
O2 required 350/0.20 =1750 kg/day.and use Two alpha factor efficiency i.e %sote and fouling of diffuser [(1750/80%)/80%].
KG of O2 required for carbonaceous BOD removal can range from 0.7 Kg/Kg BOD for high rate activated sludge with short detention of Biomass (low sludge age) up to 1.5 kg/kg BOD for extended aeration with long detention of Biomass (MLSS, i.e., (long sludge age) in the bio system,
we account 1kg/kg of BOD.
Hope, you will clear.
Thanks ?
Sir useful information but what is mean by sote for submergence of diffuser and what is mean by fouling of diffuser
Submergence mean depends on depth of aeration tank the the sote will vary more depth more percentage of oxygen transfer but increase air blower power,similarly fouling mean it affects air discharge due to excess of MLSS and other colloids in aeration tank.
What is the basis of the assumption of 0.8 for both alpha1 and alpha2.?
How can I determine it for other cases?
What will be the % oxygen transfer efficienty for 1000 mm long x 67 mm OD fine bubble tubular air diffuser silicone basaed membrane
Dear Sir,
How to calculate BOD and Air quantity in Aeration Tank
Dear sir,
if it is using jet aerators (30 hp) and blower(5 hp) then find the air producing rate per hour
You can see the manufacturer catalog, model to model it will vary and depends on Depth of installation,the output air CFM vary, plz ask the supplier, normally @ 0.5 kg/cm2 pressure you can install that jet aerator upto 4 meter depth?
Dear Sir,
Can u tell me how to calculate quantity of mbbr media required in stp/etp.
Mr.Shivanandan, what should be the optimum depth of aeration tank to get maximum SOTE ?
Regards
suggested depth 4 to 5 meter, but SOTE ! influence many factor depth, bubble size, temperature of the medium, bubble travel either it travels direct upward from the bottom of diffuser or certain inclination / angels.
Dear Sivanandan,
Can u tell me how to calculate quantity of mbbr media required in stp/etp.
sir my air requirement is 650cum/h my aeration tank depth is 4mt how to calculate blower capacity
exactly my same question
What will be efficiency need to take during actual purchase?
how can we select blower pressure?
here directly it is given to select 0.5kg/cm2.
on which factor we can select?
Please provided details calculation xygen 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
Thanks sir ! Very useful information.
Sir please provide detail calculation for pipeline distribution and diffuser requirements for the above capacity
thanks but I need how select the blower suitable ?
Very useful Easy and detailed design calculation.thank you sir
you are welcome
Our aeration tank capacity is 95 cu.m x 3nos=285cu.m.Sir how can I find matching aeration pump capacity for this plant? Recently we have 3.7kw x 3nos submersible pumps.
Thanks. What is the basis for calculating require aeration tank size, and diffuser qty
Thank you
How did you get 2734 kg/cm2
Sir, for alpha factor, it is for clean water right? may i know how to calculate alpha factor?
Then for the O2 required in the calculation is the total oxygen supply by the blower to all diffuser in the aeration tank right?
O2 requirement = 2734 kg / day how??
90 KLD Sewage Treatment Plant how much capacity blower required
From where oxygen req. 2724 kg /day came in calculation
1750/0.8/0.8=2724
Hello Sir,
I would like to Know that IF iwant to select the Air blower for MBBR tank as well as Eqt tank and Sludge tank then how to calculate the Air Requirement.
Please Explain
How did you went from 1750 kg/day to 11790 kg/day pls give detailed step. Thanks for the information, looking forward for your reply
Hi, 1750 is real O2 require, calculate 2 alpha factor 0.8 and 0.8 (1750/0.8 =2187.5/0.8=2734) further available oxygen in the air 23.2 %
so, divide 2734/0.232= 11784 so 11790 Air Require /Day(Don’t confuse this Air Quantity not Oxygen Qty)
Hope you understood well
What do you mean by alpha factor and how it’s calculated
So detailed. Thanks.
You’re welcome
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?
My STP capacity is 450KLD SBR model sir, what is the blower capacity I need to install..
If i have 300 BOD Effluent, and 200m³/day Treatment, then how much O2 required and what will be airation tank capacity, ?
What will be HRT..?
Very useful information sir thank you for your information
Thanks for your article sir.
so, if we take O2 required 350/0.20 =1750 kg/day.
1750 kg/day / 350kg BOD,
its mean O2 requirement for 1 kg BOD is 5 kg.
Sir, my STP is (SBR – 65 KL – 3 batch / day) 0). The BOD is 230 – 5. How much oxygen is required and what is the motor capacity? please explain
thank you very much