wasting should not exceed what percent what percent of total sludge volume per day?
10-15% per day? 5% per week
what is the primary advantage of vacuum-solution feed chlorinators?
safety
what do you do if the MLSS increases past the best range and the effluent quality becomes poor?
increase the WAS
the principal reason for frequent or continuos removel of sludge from a primary clarifier is?
to avoid anaerobic conditions in the clarifier.
the strength of wastewater is most clearly related to the concentration of?
organic solids. BOD/CBOD is used to test for this strength.
would you put water on a CL2 leak?
NO! forms hydrochlotic acid. *use ammonia soaked q-tip to check.
in the activated sludge system, it is essential that D.O in all parts of aeration basin be atleast?
1-3 PPM
what is the best pH range for anaerobic digester?
7.0 to 7.2
ponding is serious problem associated with a trickling filter. what is the cause of ponding?
excessive organic loading.
a low pH following clarification (settling) in an extended aeration plant probably indicates what?
MCRT to long
if you have denitrification occurring and pop-ups in your secondary clarifier, what would you do to correct this?
increase the RAS
low D.O, nutrient deficiencies, and low pH will favor the growth of_____? and what is the solution?
filamentous. increase the D.O level in the aeration tank by increasing air volume.
an unusual rise in the SVI indicates what?
there may be a danger of bulking sludge.
in the microscopic examination of the MLSS, you observe a dominance of rotifers and nematodes, what would this indicate?
old sludge which settles rapidly leaving pin floc in the effluent.
problem: localized clouds of fluffly homogenuos sludge rising in certain areas of the clarifier, mixed liquor settles slowly leaving stragglers in the supernetant. what is the probable cause?
young, low density sludge
over aeration can cause_____ in a secondary clarifier?
pin floc
anaerobic digester problem: C02 gas increase.
cause: VA/ALK ratio increased to 0.5
what is the SVI?
indicates settling properties of activated sludge. note: understand low vs. high SVI
problem: inability to maintain CL2 feed rate without icing of CL2 system?