T/F Flashcards
Temperature, Altitude, and TDS all affect the amount of DO that can dissolve in water
True
White, thick billowing foam common during the start-up of an activated sludge plant is caused by a low F/M ratio.
False, thin not thick.
Start ups have a high F/M
NPDES stands for National Pollution Discharge Elimination System.
False, P stands for Pollutant
CO2 and Ferrous Sulfide are toxic gases with offensive odors and are frequently found in confined spaces.
False
BOD is typically twice as large as the COD concentration in a given sample.
False, COD is 2x than the BOD
Nitrification involves the utilization of nitrate ions by facultative bacteria and the release of nitrogen gas.
False, It’s denitrification
Sodium Thiosulfate is often used to destroy residual CL2 in a SE sample for DO
False, used only in coliform samples
MSDS are only maintained for chemicals that are either purchased or stocked in quantities of 100 lbs (10 gallons, if liquid) or more.
False
Higher surface loading rates will generally result in a lower percent removal of BOD and TSS
True, An increase in HLR/SOR means an increase in velocity
An abundance of filaments in the activated sludge mixed liquor is generally an indicator of bulking.
True, higher filaments = higher SVI
Using the F/M ratio to control the activated sludge process implies that an increase in the mass of microorganisms will be needed to treat an increased BOD or COD load
True
When starting an anaerobic digester with a small amount of seed and a typical load of raw sludge, the operator should see a drop in a pH of the DS
True
If the vacuum is lost in a CL2 system, the flow is automatically shut off
True
Sodium nitrate has been added to treatment ponds for the purpose of odor control because it will oxidize odor causing substances.
False, Like Ca(NO3)2 bioxide, it prevents the formation of sulfides
Advanced primary treatment involves the addition of ferric chloride or other coagulants to improve the removal of finely divided solids.
True
Step feed aeration involves the adjustments in the rates of aeration along the length of the aeration tank.
False, it distributes the BOD load down the length of the aeration basin
Typical organic loading for high rate trickling filters is between 25-100 gpd/sqft
False, OL is in lbs of BOD/ d*1000ft3 of media
Volatile Solids reduction in a well operating anaerobic digester should be 50% or greater.
True
Demand charge on a WWTP’s bill is measured in units of kilowatt-hours
False, $/Kilowatt
A progressive cavity pump is generally classified as a positive displacement pump.
True
N gas and CO2 are odorless, colorless, and non-flammable but could cause asphyxiation at concentrations much greater than normal.
True
High I/I could contribute to poor performance of both primary and secondary processes.
True
Careful application of chlorine to the flow being applied to a trickling filter may be used to correct certain operational problems,
True
Most nitrogen in raw domestic sewage is either in the form of organic compounds such as proteins or as nitrate salts.
False
Mud valves are built into many treatment plant basins that extend below ground level in order to prevent damage from hydrostatic pressure
True
