ACTIVATED SLUDGE AND NUTRIENT REMOVAL
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A wastewater treatment plant based on activated sludge with biological phosphate and nitrogen removal via pre-denitrification. The influent flow (dwf) is 30,000 m3/day and the influent BOD concentration is
300 mg BOD/l. The suspended solid concentration in the influent is 150 mg/l of which 40% is removed in the primary clarifier. The sludge recycle flow ratio (fr) is 0.5, the sludge yield (Y) is 0.6 kgX/kgBODremoved and the SVI is 130 mL/g.
The treatment plant consists of different process units, namely:
Final clarifier
Screen
Aerobic tank
Primary sedimentation
Anoxic tank
Grit chamber
Anaerobic tank
Sludge dewatering
After dewatering the sludge will be directly transported to the sludge incineration plant.
Q1:What is the minimum size (volume) in m3 of the aeration tank?
Calculate with a biomass concentration in the aeration tank of 4 g/l and take into account that the primary settler removes 33% of the BOD.
Q2:What would be the size (volume) in m3 of the anaerobic tank (don’t forget the sludge recycle flow to the anaerobic tank)?
Q3:What would be the waste activated sludge (or surplus sludge production) in kg dry weight per day?
Calculate the biomass production assuming all BOD entering the biological process is removed. Also add the primary sludge production, but for simplicity neglect the remainder of the suspended solids.
The biomass production (kg biomass per day) is:?
The primary sludge production (kg per day) is:?
Q4:The sludge is directly dewatered to a final dry solid concentration of 18%. How much trucks, that can transport a load of 30 ton, will be needed per year for sludge transport to the incineration plant?
Q5:How can the produced sludge be reduced maximally, to minimize transport costs?
a//Application of chemical conditioning .b//Application of sludge digestion.c// By thickening of the primary sludge
Question 3d
What would be the size (volume) in m3 of the anaerobic tank (don’t forget the sludge recycle flow to the anaerobic tank)?
Answer =1875
2C1=1.22
2C2=0.34 (velocity) 2C2=32(head loss)
2D2 length=11.85
width=0.79
hight= 0.43
grit chanel=0.78
2E
any one can answer this please?? thank you
please tell all the answers for WEb and WEc
thank you Anonymous i got already answer.
Can you help me with answers of this question? I would be grateful :)
please tell the answers ham i wanna pass this , please!!_/\_
screen -->coarse material
grit chamber -->xxx
primary sedimentation -->xxx
anaerobic tank-->xxxx
anoxic tank--->xxxx
aerobic tank-->nitrification
final clarifier-->xxxx
sludge dewatering -->remove water from the sludge
help me with Q3C Q3D Q3E
what answer you want pls?/
1.Screen>>coarse material
2. Grit chamber>>sand
3.Primary Sedimentation >>Suspended solid & settle able part of BOD
4.Anaerobic tank >>Hydrolysis of Xs & uptake of Ss
5.Anoxic tank >>Denitrification
6.Aerobic tank >>Nitrification
7.Final clarifier >>Separating Biomass & effluent
8.Sludge De watering >> remove water from sludge.
Question 3c
What is the minimum size (volume) in m3 of the aeration tank?
Calculate with a biomass concentration in the aeration tank of 4 g/l and take into account that the primary settler removes 33% of the BOD.
Answer =10050
i will be here another couples of hours if any one looking for other answer pls paste me here Urgent...
3G and 3F
Thank you, Ham!
Wastewater from a small town is treated in a trickling filter which is preceeded by a screen, sand-removal and primary clarification. The maximum hydraulic capacity, or peak flow, of the treatment plant is
1,500 m3/h. The dry weather flow (Qdwf) amounts 7,500 m3/day, with a BOD concentration of 300 mg/l.
Additional information
After this pre-treatment the water is fed to a trickling filter. The diameter of this trickling filter is 30 m and its height is 3 m.
Assume for the next question no BOD removal in the pre-treatment, so influent BOD concentration is 300 mg/l.
QUESTION 2E
Calculate the loading rate (kg/m3/day) of the trickling filter.
QUESTION 2D-2 (4 points possible)
Assume 4 channels. Take a W:L ratio of 1:15
Dimension the rectangular sand removal channels.
Length (m):
Width (m):
Maximum water height (m):
Allow a free waterboard of 15 cm and a maximum grit accumulation height of 20 cm. Give the total height in m of the grit channel.
2D1 and 2D3 Nilu please!!
2C1 2C2 2D1 2D3 please someone tell the answer i really need it!!
thank you :)
2D1
Determine how many parallel channels you will design.ANS 4
What is a common W:L ratio? ANS 1:10
To prevent settling of organic matter a Vs should be Ans---higher than 0.03m/s
Calculate Qdwf in m3/s.---my answer is wrong
Calculate Qrwf in m3/s.my answer is wrong
2D3
Calculate the liquid velocity during Qdwf (in m/s) in the channel.my answer is wrong
Organic matter will settle in the channel during Qdwf.Ans-False
PLEASE 2C1 AND 2C2,2D2
2D1:
4
1:10
higher than 0.03 m/s
2C1 2C2 2D2 anyone??? please help fast!!
@ IG please 2C1 , 2C2,2D2
please any one know correct answer
Nilu please help me with 3B and 3F i wud be very gratefull to you!! thank you :)
Please 2C1, 2C2,2D2,2E
Sorry, haven't got it :(
3B and 3F ??
sorry 3B and 3F!!
please help I.G
3F
Denitrification takes place inside the granule +
Due to reduction of oxygen in the outer layer, anoxic conditions will exist inside the granule +
Aerobic granules make settling tanks superfluous
@Anonymous,PLEASE 2C1, 2C2,2D2,2E
i got 3F and 3G wrong answerCRAZY ONE,
Haven't got 3B, sorry :(
3b??
Please 2C1, 2C2,2D2,2E
yea please someone help with 2C1, 2C2,2D2,2E _/\_
3b chamber filter ,beltfilter,centrifuge
Please 2C1, 2C2,2D2,2E please answer
hi i am here which answer is needed??
Ham, Please 2C1, 2C2,2D2,2E please answer
2C1, 2C2,2D2,2E??
3G??
Nilu did u get the answers?? :/
i stop here 2C1, 2C2,2D2,2E
Ham please help man!!!
2E=1.06 (tricling filter)
anon which one you want ??
THANK YOU SO MUCH HAM,you are ROCK
any one still need me??
Ham, do you have 2D3? Thank you so much for everything!!
And 3G?
Anon ??
2D3??
3G man?
3 G myself i got wrong already... sorry
I wish to SOMUCH THANK YOU for this TEAM work,All the Best ,I scored 77% that is enough,no need to too much,enjoy and cheers
Next traping point is SOLAR EXAM 2 AND EXAM 3
Any one take Introduction of Operational Mangement from Coursera
2D3=i got wrong (Qdwf (in m/s) in the channel.)
False (correct)
Ham no need every thing, 50% answers sharing good,we need to do some home work,Thank you Ham,On solar exam i scored 72%,still pending exam3
oki any one still need me??
though i got myself less than 70% :(
here is some fello passing wrong answer that is not good.. Anon you oki??
2B and 2C from 2nd week? Does anyone know the answers?
Many tks
Wastewater from a small town is treated in a trickling filter which is preceded by a screen, sand-removal and primary clarification. The maximum hydraulic capacity, or peak flow, of the treatment plant is 1,500 m³/h. The dry weather flow (Qdwf) amounts 7,500 m³/day, with a BOD concentration of 300 mg/l.
The maximum scouring velocity or slip velocity is 0.3 m/s and the maximum surface load or Hazen velocity is 40 m/h.
Question 2a
0.0/2.0 points (graded)
Assume 4 channels. Take a W:L ratio of 1:15
Calculate the vertical surface area Avertical in m²:
unanswered
Calculate the horizontal surface area Ahorizontal in m²:
unanswered
Question 3e
What would be the waste activated sludge (or surplus sludge production) in kg dry weight per day?
1. Calculate the biomass production assuming all BOD entering the biological process is removed. Also add the primary sludge production, but for simplicity neglect the remainder of the suspended solids.
The biomass production (kg biomass per day) is: Answer=3618
The primary sludge production (kg per day) is: Answer=1800
2:The sludge is directly dewatered to a final dry solid concentration of 18%. How much trucks, that can transport a load of 30 ton, will be needed per year for sludge transport to the incineration plant? Answer=365
3:How can the produced sludge be reduced maximally, to minimize transport costs?
Answer=Application of sludge digestion