Yellow
What is the design average flow of 1 primary clarifier?
1.5 MGD
What is the hydraulic detention time of 1 primary clarifier?
1.8 hours
The primary effluent has a CBOD concentration of 250 mg/L and the plant influent has a concentration of 350 mg/L, what is the percent removal?
28.6%
How many mLs of primary sample get put into the bottle for the BOD test?
6 mL
Can you adjust the primary pump speed?
No. It is a constant speed pump
What is the design peak flow of 1 primary clarifier?
4.5 MGD
What is the peak hydraulic detention time of 1 primary clarifier?
0.6 hours
The primary effluent has a TSS reading of 90 mg/l and the plant influent has a reading of 330 mg/L, what is the percent removal?
72.7%
How many GPM is 1.5 MGD?
1,042 GPM
Can ferric chloride be directly added to the primary clarifiers?
No
How long is the primary clarifier?
62 feet
What is the average flow surface overflow rate of 1 primary clarifier?
870 gpd per square foot
Assuming the primary clarifier holds 60,000 gallons, what is the actual detention time if the flow is 0.6mgd?
2.4 hours
How many GPM is 1.0 MGD?
694 GPM
What is the horsepower of a primary sludge pump?
5
How wide is the primary clarifier?
14 feet
What is the peak surface overflow rate of 1 primary clarifier?
2,620 gpd per square foot
Name four things a primary clarifier removes.
TSS, Oil, Grease, BOD
The primary sludge should be above what percent volatile solids?
80%
What type of flow meter measures the flow leaving the primary pumps?
Mag meter
What is the side water depth of the primary clarifier?
8.75 feet
How much water will the scum tank hold?
1,100 gallons
Why do we use only one primary clarifier?
Having two online would take out too much food for the microbes.
When should we go to two?
What are two types of solids removed by primary clarifiers?
Settleable and floatable
What type of pumps are the primary sludge pumps?
Rotary Lobe