wayground logo

Free Printable Worksheets

Font size

S
M
L
XL
Worksheets

Secondary treatment

Total questions: 56

Worksheet time: 38mins

Name
Class
Date
1.

What is the first step in the water treatment process?

a)

coagulation

b)

filtration and removal of debris, sand, grit, etc.

c)

flocs

d)

concentation

2.

What is the first step in the water treatment process?

a)

coagulation

b)

filtration and removal of debris, sand, grit, etc.

c)

flocs

d)

concentation

3.
What word means the solid particles that have settled out during the sedimentation process.
a)
sediment
b)
solubility
c)
settlement
d)
solidifying
4.

Preliminary treatment

a)

prevents toxic chemicals.

b)

removes large objects.

c)

is unnecessary.

d)

is useless.

5.

Which substance is used in a sewage treatment system to kill harmful bacteria?

a)

ammonia

b)

chlorine

c)

sand

d)

soap

6.
What is the purpose of using ultraviolet light on the water?
a)
To bleach it out
b)
To "sterilize" any bacteria 
c)
To remove chlorine
d)
To kill viruses
7.
What is the role of bacteria in the water purification process?
a)
digested organic matter
b)
add chlorine
c)
nothing, we don't want them in there
d)
add nutrients to the sludge
8.
What was the name of the brown wastewater solution in the aeration tank?
a)
sludge
b)
effluent
c)
mixed liquor
d)
sewage
9.
What gas must be maintained at precise levels in the aeration tank?
a)
CO2
b)
O2
c)
H2
d)
CO
10.

What is the first step of preliminary wastewater treatment, which removes large items such as plastic wrappers and sticks?

a)

screening - employs the use of a "bar screen"

b)

sedimentation

c)

aeration

d)

disinfection

11.

List the following steps of Water purification in the correct order

Step P: Water is passed through a screen to remove debris.

Step Q: Pathogenic organisms are killed by chlorination, UV, or ozone.

Step R: Suspended particles clump and settle out.

Step S: A flocking agent, such as alum, is added to the water.

a)

P, Q, R, S

b)

S, P, R, Q

c)

P, S, R, Q

d)

R, P, S, Q

e)

S, R, P, Q

12.

Which method introduces microorganisms to break down hazardous organic compounds?

a)

Sanitary landfill

b)

Incineration

c)

Discharge to sewers, streams, and rivers

d)

Chemical treatment

e)

Biological treatment

13.
Bacteria are beneficial to wastewater treatment because
a)
they naturally break down organic matter
b)
they help solid material to settle out of the wastewater
c)
the nutrients produced are beneficial to the treated water
d)
they aren't beneficial
14.
The principle advantage of using wetlands for wastewater treatment is:
a)
the resulting water exceeds all drinking water standards 
b)
a natural ecosystem replaces industrial methods for advanced treatment
c)
it removes dioxin and other pollutants in the sediment of the wetland
d)
the method eliminates the production of methane, which contributes to global warming
15.
What does chlorination do to the water?
a)
Removes microorganisms
b)
Cleans the water
c)
Makes the water taste nice
d)
Removes twigs and sediment
16.

In which part of the wastewater treatment process are bacteria introduced to the wastewater to feed on organic particles, such as food and feces? (Select 2 choices)

a)

sedimentation

b)

aeration

c)

disinfection

d)

primary treatment

e)

secondary treatment

17.

In the wastewater treatment process, what is the role of bacteria for water purification?

a)

digesting organic matter

b)

adding chlorine

c)

nothing, we don't want them in there

d)

add nutrients to the sludge

18.

The material that is removed from the wastewater, sent through the belt press and requires proper treatment and disposal methods is called

a)

sediment

b)

sludge

c)

mixed liquor

d)

aeration

19.

What is no longer added to the water treatment process?

a)

sludge

b)

aeration

c)

fluoride

d)

sodium

20.
What is the purpose of using ultraviolet light on the water?
a)
To bleach it out
b)
To "sterilize" any bacteria 
c)
To remove chlorine
d)
To kill viruses
21.
What causes foam in the water?
a)
pollution
b)
excess bacteria
c)
trapped air
d)
too much chemical treatment
22.

Water flows through a filter designed to remove the particles form.

a)

Agitation

b)

Coagulation

c)

Filtration

d)

Flocculation

23.

Things we can do to save clean water, except:

a)

Taking shorter showers

b)

Make sure to pick up your trash

c)

Make sure to turn off the running tap when not in use

d)

Pour dangerous chemical solutions to the sink

24.

These are steps of wastewater treatment, except:

a)

Flocculation

b)

Saponification

c)

Coagulation

d)

Sedimentation

25.

What disease is cause by water pollution? Except ...

a)

Cholera

b)

Influenza

c)

Tuberculosis

d)

Chickenpox

26.

How does the development of urban area affect the river?

a)

No effect at all

b)

Water remains stable

c)

Pollutes the water

d)

Water tastes funny

27.

What is Sludge?

a)

The wastewater and other different types of waste.

b)

A network of pipes that carry sewage.

c)

A dense material that sinks to the bottom of the septic tank.

d)

A material that floats at the top of a septic tank.

28.

What is Sewage?

a)

Wastewater and other different types of waste.

b)

A network of pipes that carry sewage.

c)

A dense material that sinks to the bottom of the septic tank.

d)

A material that floats at the top of a septic tank.

29.

What is Scum?

a)

Wastewater and other different types of waste.

b)

A network of pipes that carry sewage.

c)

A dense material that sinks to the bottom of the septic tank.

d)

A material that floats at the top of a septic tank.

30.

What is a Sanitary Sewer?

a)

Wastewater and other different types of waste.

b)

A network of pipes that carry sewage.

c)

A dense material that sinks to the bottom of the septic tank.

d)

A material that floats at the top of a septic tank.

31.

What is a Septic Tank?

a)

A place where wastewater flows through screens to catch large particles.

b)

An underground tank that contains bacteria that treats wastewater.

c)

A place in which the wastewater is filtered through a bed of gravel that is covered with colonies of bacteria.

32.

The process of settling down of particles of a solid in a liquid is

a)

Sublimation

b)

Sedimentation

c)

Filtration

d)

Decantation

33.

The solubility ____________ with increase in temperature.

a)

doesn't change

b)

decreases

c)

increases

34.
The diagram shows the apparatus for separating soil and water. What are the labelled parts?
a)
A = distillate, B = filtrate
b)
A = filtrate, B = residue
c)
A = residue, B = filtrate
d)
A = residue, B = distillate
35.
Filtration can be used to separate...
a)
an insoluble solid from a solution
b)
a soluble solid from a solution
c)
a dissolved solid from a solution
36.

Sawdust is not soluble in water. If, accidentally some particles of sawdust drop into a glass of water. How would you separate them from water?

a)

Decanting

b)

Filtering

c)

Sieving

d)

Distillation

37.
What is the first step in the water treatment process?
a)
coagulation
b)
filtration
c)
flocs
d)
concentation
38.
During secondary treatment in the aeration tanks, what is working on the sewage waste?
a)
micro-organisms
b)
humans
c)
air titration
d)
oxidation/reduction
39.

What is a sewage treatment plant?

a)

The place where water is cleaned, filtered and tested before re-entering the water cycle.

b)

The place where water is cleaned, filtered and tested before going to our houses.

c)

The network of pipes that carry sewage (dirty water) from our houses.

d)

The place where water is bottled for drinking.

40.

Advantages of Sewage System

a)

The domestic sewage treatment plant needs to be running

steadily to be effective.

b)

The sewerage system provides a healthier and more appropriate way to manage liquid wastes.

c)

The sewerage system provides a healthier and more appropriate way to manage solid wastes.

41.

Disadvantages of Sewage System

a)

The domestic sewage treatment plant needs to be running

rarely to be effective.

b)

It must be permanently supplied with electricity to

operate.

c)

Waste Will Be Discharged

42.

Sewage is mainly

a)

Liquid Waste

b)

Solid Waste

c)

Gaseous waste

d)

Mixture of solid and gaseous waste

43.

Treatment of sewage can be done by ___________, ___________, and _____________ types of processes.

a)

Physical

b)

Chemical

c)

Biological

d)

Mechanical

44.

What are the three types of primary treatment?

a)

aeration

b)

Screening

c)

Grit and sand removal

d)

Primary sedimentation

45.
What is the role of bacteria in the water purification process?
a)
digested organic matter
b)
add chlorine
c)
nothing, we don't want them in there
d)
add nutrients to the sludge
46.
What gas must be maintained at precise levels in the aeration tank?
a)
CO2
b)
O2
c)
H2
d)
CO
47.
Bacteria are beneficial to wastewater treatment because
a)
they naturally break down organic matter
b)
they help solid material to settle out of the wastewater
c)
the nutrients produced are beneficial to the treated water
d)
they aren't beneficial
48.

Attached film differs from the suspended system because

a)

presence of media

b)

type of microbes

c)

length of treatment

d)

type of treatment

49.

Decomposition caused by anaerobic bacteria is sometimes called as _____, is accompanied by bad odor

a)

Putrefaction

b)

Decomposition

c)

Oxidation

d)

Sedimentation

50.

A sewage that turns dark and smell unpleasantly due to anaerobic decomposition is called _____

a)

Black water

b)

Grey water

c)

Yellow water

d)

Septic

51.

Bacteria which still functions even with or without free oxygen

a)

Aerobic

b)

Anaerobic

c)

Facultative

d)

Septic

52.

Develop a sustained BOD peak mass loading curve for a treatment plant with a design flowrate of 1 m3/s. Assume daily BOD concentration is 200 g/m3. What is the mass loading value for BOD, kg/d?

a)

5000

b)

200

c)

2000

d)

17280

53.

Advantages of having anaerobic treatment over aerobic treatment process

a)

energy input of the system is low as no energy is required for oxygenation

b)

lower nutrient requirement

c)

lower production of excess sludge

d)

higher biological synthesis

54.

Biochemical process in the anaerobic treatment

a)

hydrolysis

b)

fermentation

c)

acetogen

d)

methane

55.

Physical design similar to AEBR only uses higher liquid velocity

a)

FBR

b)

UASB

c)

EBR

d)

RBC

56.

This treatment can be applied both in aerobic and anaerobic condition

a)

RBC

b)

Trickling filter

c)

BAF

d)

UASB