Ch. 14 Flashcards
- Toxicity levels in wastewater treatment are measured in __________.
a. mg/L
b. kg/L
c. mg/mL
d. kg/kL
e. mg/ML
a. mg/L
- The upper PH level limit for wastewater is at _____ .
a. 8
b. 8.5
c. 9
d. 9.5
e. 10
b. 8.5
- The lower Ph level limit for wastewater is at _____.
a. 5.5
b. 6
c. 6.5
d. 7
e. 7.5
c. 6.5
- In regards to wastewater the abbreviation BOD means; ___________________.
a. bad oil damage
b. biodegradable oil demand
c. biochemical odor department
d. biochemical oxygen demand
e. biochemical oxygen damage
d. biochemical oxygen demand
- The temperature of the water being dumped into the receiving water is important. The higher the temperature the higher the need for _________________________.
a. chemical treatment
b. deaeration
c. acidity test
d. direct input to the river
e. a means of cooling the incoming water
e. a means of cooling the incoming water
- Methods of cooling the wastewater prior to dropping the incoming water into the receiving water are:
1) Cooling towers 2) Deaeration 3) Long serpentine channels 4) Retention ponds
a. 1, 3, 4
b. 1, 2, 4
c. 2, 3, 4
d. 1, 4
e. 2, 3
a. 1, 3, 4
- The added benefit of using a cooling tower to cool the wastewater is ______________________.
a. some of the water evaporates in the air, less to take care of
b. it increases the dissolved oxygen content of the wastewater
c. it will cool the wastewater below ambient temperature
d. no operator required
e. the chemical oxygen demand is increased
b. it increases the dissolved oxygen content of the wastewater
- To allow for reasonable separation in an oil/water separation pond, which is a component of an industrial wastewater treatment plant, the separator should have sufficient capacity to hold the average flow for _________ .
a. 1 day
b. 1 to 2 days
c. 2 to 3 days
d. 3 to 4 days
e. 4 to 5 days
c. 2 to 3 days
- The stabilization lagoon should be large enough to hold the effluent of the of the oil/water separation pond to contain _________ discharge from the plant.
a. one week
b. two weeks
c. three weeks
d. one month
e. two months
d. one month
- In order to enable aerobic bacteria and other organisms to break down the organic components in the wastewater __________ are used.
a. clarifiers
b. chemicals
c. enzimes
d. a combination of sun lights and ultra violet light
e. compressed air bubbles
e. compressed air bubbles
- ___________________ is/are mixed with the effluent of the wastewater heater to help breakdown the organic materials in the flow.
a. Activated sludge
b. Activated chemicals
c. Oils
d. Polishing chemicals
e. Steam
a. Activated sludge
- In the clarifier some of the activated sludge is sent back to the first stage aeration tank, the remainder is sent to __________.
a. wastewater heater
b. disposal
c. second stage aeration
d. polishing pond
e. oil/water separation pond
b. disposal
- The removal of inorganic material in municipal wastewater system is carried out in grit and screen sections. This removal section is sometime known as _________.
a. tailworks
b. hardworks
c. headworks
d. midworks
e. removalworks
c. headworks
- The primary separation of suspended solids is facilitated by_________.
a. pumps
b. chemicals
c. activated sludge
d. gravity
e. rotating biological contactors
d. gravity
- Grit, which has been removed from the wastewater in the grit chamber, is then disposed off _________.
a. in barrels
b. in an incinerator
c. in a toxic dump
d. on farmers field
e. in landfill
e. in landfill
- A rotating trash screen used in a wastewater treatment plant is also called a ________________.
a. comminuter
b. compactor
c. constrictor
d. accumulator
e. barminutor
a. comminuter
- In a wastewater plant, some organic material accumulates on the screen, this organic material is acceptable as landfill material.
a. True
b. False
b. False
- An ångström unit is equivalent to ____________.
a. 10-10
b. 10-6
c. 10-3
d. 10-2
e. 10-1
a. 10-10
- _________ particles, are so small that they will not settle at the bottom or float to the top.
a. ångström
b. Colloidal
c. Activated sludge
d. Barminutor
e. Grit
b. Colloidal
- This wastewater process involved changing the charge of the colloidal particles is called_________________.
a. coagulation
b. floatation
c. flocculation
d. sedimentation
e. clarifier
c. flocculation
- This wastewater process involves changing the colloidal particles charge, attaching them to polyelectrolites, and allowing them to settle is called______________.
a. sedimentation
b. floatation
c. flocculation
d. coagulation
e. clarifier
d. coagulation
- In the coagulation process the sedimentation takes about _____ hours.
a. 0.5
b. 1
c. 2
d. 3
e. 4
e. 4
- Coagulation involves the following processes
1) Mixing 2) Floatation 3) Flocculation 4) Stabilization lagoon 5) Settling
a. 1, 3, 5
b. 2, 3, 4
c. 3, 4, 5
d. 1, 2, 3
e. 1, 4, 5
a. 1, 3, 5
- The bacteria in activated sludge needs ________ to live.
a. water
b. oxygen
c. sugar
d. aluminum sulphate
e. salts
b. oxygen
- The bacteria in activated sludge feeds on _________in the wastewater.
a. aluminum sulphate
b. salts
c. organic material
d. polyelectrolytes
e. water
c. organic material
- A rotating biological contactors main purpose is to reduce the ________ of the wastewater.
a. temperature value
b. acidity value
c. toxicity
d. biochemical oxygen demand value
e. PH value
d. biochemical oxygen demand value
- The shaft of a rotating biological contactor is mounted in such a way that _____ of the shaft is exposed to the air.
a. 0.1
b. 0.2
c. 0.3
d. 0.4
e. 0.5
e. 0.5
- A rotating biological contactor rotates at ____________.
a. 1 to 2 rev/min
b. 3 to 5 rev/min
c. 5 to 10 rev/min
d. 10 to 20 rev/min
e. over 20 rev/min
a. 1 to 2 rev/min
- The permeable portion of a tricking filter can be made of
1) Bed of rock 2) Screens 3) Shredder 4) Slag 5) Plastic
a. 1, 2, 3
b. 1, 4, 5
c. 2, 3, 4
d. 3, 4, 5
e. 1, 2, 3, 4, 5
b. 1, 4, 5
- The wastewater is properly cleaned when the conditions are optimized. This means _________________________.
a. the filters have a large enough diameter
b. the quality of the wastewater is below the guidelines for the plant
c. the quantity of material in the wastewater is properly matched to the right quantity and types of organisms
d. the quantity of material in the wastewater is properly matched to the right types of organisms and speed of the rotating biological contactor
e. the grit level is low
c. the quantity of material in the wastewater is properly matched to the right quantity and types of organisms
- The only place inlet samples are taken from is at the ___________.
a. flare pit
b. stabilization lagoon
c. headworks
d. oil/filter separator
e. clarifier
c. headworks
- In a PBNR process, __________ are removed.
a. carbon dioxides
b. colloidal materials
c. inorganic materials
d. phosphorus compounds
e. sand and suspended solids
d. phosphorus
- The manometer used when doing a BOD test is graduated in ___________.
a. g/L
b. kg/L
c. mg/kL
d. dg/kL
e. mg/L
e. mg/L
- When doing a settle ability test the sample needs to sit for _____ prior to taking a reading.
a. 35 min
b. 30 min
c. 25 min
d. 20 min
e. 15 min
b. 30 min
