class 1

Question 1

What is better than alum because of the broader ph range?

Answer 1

Iron Salts (ferric)

Question 2

What chemical is used for pretreatment of a facility containing metals?

Answer 2

Magnesium Hydroxide

Question 3

What is used to control struvite build up on anerobic digesters?

Answer 3

Ferric Chloride

Question 4

Has a rotten smell

Answer 4

mercaptans

Question 5

What should be the minimum depth of a clarifier?

Answer 5

7 to 10ft

Question 6

What type of microscope for filamentous organisms

Answer 6

phase contrast at 1000x power

Question 7

What type of program is used for SBR

Answer 7

programmable logic controllers

Question 8

What two things are happening if chlorine demand of plant increases?

Answer 8

Nitrite is present and incomplete nitrification

Question 9

Mesophilic Temperature range

Answer 9

85-100 F

Question 10

Thermophilic Temperature range

Answer 10

131-140 F

Question 11

What are mudballs?

Answer 11

Material, round in shape that form in filters and gradually increase when not removed from backwash

Question 12

What is log growth phase

Answer 12

Is the inital stage of bacterial growth. Is ample food supply and bacteria grow at maxium rate

Question 13

What disease can be transmitted thru wastewater

Answer 13

Hepatis A and hepatis B

Question 14

What is the most common disease to be transmitted thru wastewater?

Answer 14

Hepatitis A

Question 15

What is the most cost effective way of aeration

Answer 15

low speed turbine

Question 16

Explosive limit for gasoline

Answer 16

1.2 LEL / 7.1 UEL

Question 17

Explosive limit for methane

Answer 17

5 LEL / 15 UEL

Question 18

BOD seeding

Answer 18

2.0 mg/l minimium DO depletion and at least 1.0 mg/l Residual DO

Question 19

3 facts of filamentous organisms

Answer 19

• Nocardia SSP true branching is observed.
• Main cause of dirty brown foam is short filament
• Sphaerotilus natans are false branching is frequently observed(long filament)

Question 20

What should the DO in anoxic zone be

Answer 20

Less than .5 mg/l

Question 21

Sulfure dioxide is

Answer 21

acute toxic and corrosive

Question 22

Reverse osmosis filters only allow ?

Answer 22

water to pass, retaining salts and higher molecular weight components

Question 23

Chlorine oxidant dosage for packed bed wet scrub.

Answer 23

2-4 moles of cl2 per mole of H2s

Question 24

Sodium hydroxide dosage for packed wet bed scrubber

Answer 24

2-4 moles of NAOH

Question 25

Sodium hypochlorite dosage for packed wet bed scrubbers

Answer 25

2-4 moles of NAOCL

Question 26

Hydrogen Peroxide dosage for packed wet bed scrubbers

Answer 26

3-8 moles of h202

Question 27

What are 4 problems that cause cavitation

Answer 27

• Having pump at too high of distance above fluid
• having too long of distance of suction pipe
• pump should operate near rated head
• flow rates higher than designed flow

Question 28

What can cold temperature do to MCRT

Answer 28

the colder the temperature the longer the MCRT needed to produce a nitrified effluent

Question 29

Flagellates predominance indicate?

Answer 29

high f/m ration and low MCRT

Question 30

Ciliates predominance indicate?

Answer 30

Process is approaching stable operations

Question 31

Stalked ciliates predominance indicate?

Answer 31

Stable process that produces low turbidity effluent

Question 32

rotifiers predominance indicate?

Answer 32

Old activated sludge with high MCRT

Question 33

Suctoria predominance indicate?

Answer 33

Old sludge high MCRT