Card Set Information
what is the most important relationship in an anerobic digester ?
which gas is commomly associated with septicity? what else will cause it?
hydrogen sulfide. it will cause erosion of concrete.
incoming sludge is briefly mixed with activated sludge for 20 or 30 min. in this modification of the activated sludge process?
wastewater that is septic and is black or grey in color and contains little or no D.O is in what bacterial condition?
to compensate for or correct a rising sludge blanket, the operator should??
check the operating, lab, and process control data, inspect the aeration unit and clarifier, then determine the approriate action to take.
wastewater undergoin decomposition, black in color, and has a disagreeable odor is what
to evaluate the performance of a chlorinization system, the evaluator should check what?
contact time, chlorine residual, and bacterial count
hypochlrus acid has how many times greatest a disinfection potential than hypochlorite ion?
what happens if moisture in the air mixes with chlorine?
forms hydrochloric acid.
what is the best method to collect samples for a BOD test?
use a 24-hour composite sample with hourly sample sizes proportional to the flow.
a rise in the SVI indicates that?
sludge bulking may be occuring (sludge is bulking)
an excessive buildup of light colored foam on the aeration tank surface, large amounts of straggler floc being lost over the wier what could be the cause
WAS rate is to high
if settling test indicates the supernatant of the mixed liquor sample is clear and the supernatant of the plant effluent sample is turbid, where is the problem most likely occuring?
secondary settling tank.
sludge digestion is a decomposition process where wste material are_________?
biologically and chemically changed. note: digester is covered to keep gas in.
pumps and controls that are used to lift up water for gravity flow are called?
in an activated sludge plant, it is essential that a minimum D.O at the eflluent end of the aeration tank be?
sludge bulking can be cured by increasing the?
sludge return rate/ MCRT
foaming problems in a digester would never develop if there were?
adequate mixing present.
what measures buffer capacity in a digester?
what pump should never be started against a closed valve?