Wastewater Test 2

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What would cause sludge floc to break up in the air flotation thickners?
Incorrect flocculant dosage
Which of the following is the best lab test to measure solids in the aeration basin?
mixed liquor volatile suspended solids
What effect would adding lime to an aerobic digestor cause?
rasie alkalinity
If the sludge depth in a secondary sedimentation tank is too high, what will happen?
sludge may become septic
What chemical is used to control the pH in an anaerobic digestor?
Which test is best to measure the effectiveness of polymer?
jar test
If short circuiting is discovered in a secondary clarifier, what action should be taken?
level the effluent weirs
Although carbon dioxide gas is not poisonous, it can cause?
What chemical would you add to improve settling in a primary clarifier?
aluminum sulfate
Where should you take a sample in an aeration tank to measure solids settleabillity?
the end
Which of the following chemicals is used to control hydrogen sulfide in sewers?
What action should be taken to correct a noisy drive chain?
tighten and align the chain
Which of the following can be used to put out a gasoline fire?
carbon dioxide
A wetwell is 8 ft x 7ft. With the influent flow to the wetwell stopped , a pump lowers the wetwell level 2 ft in 5 minutes. How many gallons per minute is the pumping rate?
Which of the following will affect pressure in a pipe?
What chemical typically used to pretreat sludge prior to dewatering?
Over lubrication of a shaft bearing can result in what?
the bearing will overheat and cause damage
What causes cavitation in centrifugal pumps?
pumping against hight discharge head then specifications
When adjusting the packing gland after re-packing a pump, how should you tighten it?
slowly, over a period of hours until you obtain the desired weepage
A cross connection is a direct connection between what?
potable water and non-potable water
What DO level should be maintained in an activated sludge aeration tank?
1-2 mg/L
When a sprocket of a chain drive mechanism on a screen starts to wear what do you do?
turn the sprocket over and order a replacement
Hom many gallons will a 12in diameter pipe hold if the inside of the pipe is uniformly coated with 1 inch grease and is 300 feet long?
With a flow of 510,000 gallons per day, a chlorine feed of 250 pounds per day and a chlorine residual of 3 mg/L, what is the chlorine demand in mg/L?
On a manually cleaned barscreen, the wasterwater is 9 inches higher on the influent side. What is the cause of the problem?
the barscreen is clogged