Water Treatment Class 3
(133).jpg "Water Treatment Class 3 - Quiz")
Water treatment refers to any process that makes water more suitable for a specific use – i. E. Drinking, irrigation, bathing, recreation, river flow maintenance and a host of other uses. What do you know about water treatment?
- 1.The filter rate and backwash rate of each filter shall be determined and recordedonce each
- A.
Week
- B.
Month
- C.
Quarter
- D.
Year
- 2.The culture media used in the presumptive test is of
- A.
Agar
- B.
A brilliant green lactose bile broth
- C.
A lactose or lauryl tryptose broth
- D.
A nutrient agar
- 3.Fish eyes are
- A.
Undissolved clumps in solution
- B.
The primary cause of floc carryover
- C.
Spots of coagulant attaching to the sides of the basin.
- D.
An unavoidable operating problem associated with solution tanks
- 4.Water may be aerated by several methods, almost all of which involve
- A.
Covering the storage facilities
- B.
Exposing a large surface area to the atmosphere
- C.
Increasing the pressure
- D.
Reducing its temperature
- 5.All chlorine cylinders are required to contain at least one fusible metal safety device (plug) designed to melt at between _____ Degrees F
- A.
98 - 105
- B.
120 - 150
- C.
158 - 165
- D.
200 - 212
- 6.What is the amount of chlorine required to treat 5 mil gal of water to provide a 0.8ppm residual and satisfy 2.4 ppm chlorine demand?
- A.
33.33 lb
- B.
66.67 lb
- C.
100.00 lb
- D.
133.33 lb
- 7.The detention time usually required in a conventional straight-flow sedimentationbasin is _______ h.
- A.
0.5 - 1
- B.
2 - 6
- C.
10 - 12
- D.
24
- 8.Air binding is a condition that may occur as a result of
- A.
Filter-bed compaction
- B.
Gravel displacement
- C.
Negative head.
- D.
Reaching terminal head loss.
- 9.A program for the control of algae should be instituted
- A.
On a routine, periodic schedule, but not to exceed two applications per year
- B.
On a seasonal basis
- C.
After trend information has been established and adequate monitoring is practiced.
- D.
During extended periods of warm water temperatures
- 10.With the coming of winter, the water temperature drops. A likely operational problem at a filtration plant with coagulation is
- A.
Floc carryover from the sedimentation system
- B.
High alkalinity
- C.
High chlorine residual
- D.
Odor.
- 11.A fluoride saturator
- A.
Can only be used by large treatment facilities
- B.
Eliminates the need for a metering pump
- C.
Eliminates the need for chemical handling.
- D.
Is suitable for small water systems
- 12.The most desirable place to feed activated carbon in a lime-soda ash softening plant is
- A.
After lime feed.
- B.
In the clearwell
- C.
To raw water at earliest stage possible.
- D.
With lime feed
- 13.Activated alumina is used effectively for the removal of
- A.
Certain inorganic elements
- B.
Herbicides and pesticides
- C.
Humic substances
- D.
Oxidized precipitates
- 14.Four milligrams per litre of chlorine is added continuously to a water flow thataverages 5 mgd. How much chlorine will be used in 30 days?
- A.
1500 lb
- B.
3000 lb
- C.
5000 lb
- D.
15,000 lb
- 15.Harvesting, dewatering, dredging, shading, and lining are all methods for controlling rooted aquatic plants
- A.
Without much effort
- B.
Physically
- C.
Chemically.
- D.
Biologically
- 16.Sodium hydroxide (NaOH) is often used as the base in acid-base titrations. It has a molecular weight of 40 (23 + 16 + 1 = 40). How many grams of NaOH are in 1 L of a 1N (normal) solution?
- A.
20
- B.
40
- C.
60
- D.
80
- 17.When using the multiple-tube fermentation test method and coliform organismsoccur in six out of ten of the 10-mL portions of a single standard sample, then
- A.
Customers should be told to boil their water
- B.
The system must collect a set of repeat samples within 24 h.
- C.
The chlorine residual should be increased to 1.0 mg/L
- D.
The water main should be flushed for 24 h.
- 18.Fire fighting may cause low pressure in an area of a distribution system. The lowpressure might lead to
- A.
Contamination of the system by backsiphonage
- B.
Ice formation in the pipes
- C.
Loss of chlorine residual
- D.
Muddy water.
- 19.Pinpoint floc is a condition associated with
- A.
Flash mixing
- B.
Low turbidity
- C.
The type of chemical selected.
- D.
Water temperature
- 20.Sedimentation can be improved by
- A.
Lowering the water temperature after flocculation.
- B.
Maintaining a uniform, horizontal, low-velocity flow across the basin
- C.
Maintaining a uniform sludge blanket
- D.
Reducing the detention time
- 21.A carbon dosage of 20 mg/L is required for the removal of taste and odors. With aflow of 5560 gpm, how many pounds of carbon should be fed per hour?
- A.
27.8 lb
- B.
49.9 lb
- C.
55.6 lb
- D.
668.0 lb
- 22.If a filter has been out of service and allowed to go dry, which filter control valveshould be used to refill it with water?
- A.
Effluent valve
- B.
Influent valve
- C.
Rewash valve
- D.
Backwash inlet valve
- 23.A liquid has a specific gravity of 1.16. How much would 300 gal of this liquid weight?
- A.
158
- B.
348
- C.
2502
- D.
2899
- 24.Polyelectrolytes are
- A.
Coagulants
- B.
Coagulant aids.
- C.
Used for hardness reduction
- D.
Used for pH adjustment
- 25.A tank 6 ft in overall length and 18 in. in diameter is in the shape of a cylinder withtwo hemispherical ends. Its capacity is ______ gal.
- A.
7.7
- B.
72.7
- C.
270
- D.
17.20