Environmental Science Midterm 3

Front 1

It is the mixture of gases which forms the Earth's atmosphere and a means by which we breathe

Back 1

Air

Front 2

The ______ in Earth’s atmosphere is made up of approximately 78 percent nitrogen and 21 percent oxygen.

Back 2

Air

Front 3

The air in Earth’s atmosphere is made up of approximately ____ percent nitrogen and ______ percent oxygen.

Back 3

78

21

Front 4

Soot, smoke, mold, pollen, methane, and carbon dioxide are a just few examples of common _______.

Back 4

pollutants

Front 5

A mix of particles and gases that can reach harmful concentrations both outside and indoors. Its effects can range from higher disease risks to rising temperatures.

Back 5

AIR POLLUTION

Front 6

SOURCES & EFFECTS OF AIR POLLUTION

Back 6

✓ Sulfur and Nitrogen Oxides / Acid Rain

✓ Photochemical Smog

✓ Ozone Depletion

✓ Global Warming (Climate change)

✓ Other sources of air pollutants

✓ Indoor Air

Front 7

It is any of several compounds of sulfur and oxygen.

Back 7

Sulfur Oxides

Front 8

It is a heavy, colorless, poisonous gas with a pungent, irritating odor familiar as the smell of a just-struck match.

Back 8

Sulfur dioxide

Front 9

Sulfur dioxide is a heavy, colorless, poisonous gas with a

______, irritating odor familiar as the smell of a just-struck match.

Back 9

pungent

Front 10

Sulfur dioxide is a heavy, colorless, poisonous gas with a pungent, irritating odor familiar as the smell of a _______.

Back 10

just-struck match

Front 11

Large quantities of sulfur dioxide are formed in the combustion of _________.

Back 11

sulfur-containing fuels

Front 12

It is a colorless compound that exists at room temperature either as a volatile liquid or in any of three allotropic solid forms.

Back 12

Sulfur trioxide

Front 13

Sulfur trioxide is a colorless compound that exists at room temperature either as a volatile liquid or in any of three

________.

Back 13

allotropic solid forms

Front 14

_________ is a very powerful dehydrating agent, very corrosive, and reactive chemical.

Back 14

Sulfur trioxide

Front 15

Sulfur trioxide is a very powerful ___________, very corrosive, and reactive chemical.

Back 15

dehydrating agent

Front 16

Formed mainly from N2 and O2 during high-temperature combustion of fuel in cars.

Back 16

Nitrogen oxide

Front 17

It contributes to acid rain because they combine with water to produce nitric acid (HNO3) and other acids.

Back 17

Nitrogen Oxides

Front 18

Nitrogen oxides also contribute to acid rain because they combine with water to produce ________ and other acids.

Back 18

nitric acid (HNO3)

Front 19

Itis a broad term that includes any form of precipitation with acidic components, such as sulfuric or nitric acid that fall to the ground from the atmosphere in wet or dry forms.

Back 19

Acid rain or acid deposition

Front 20

Acid rain, or acid deposition, is a broad term that includes any form of _______________, such as sulfuric or nitric acid that fall to the ground from the atmosphere in wet or dry forms.

Back 20

precipitation with acidic components

Front 21

This can include rain, snow, fog, hail or even dust that is acidic.

Back 21

Acid rain

Front 22

A type of smog produced when ultraviolet light from the sun reacts with nitrogen oxides in the atmosphere.

Back 22

Photochemical Smog

Front 23

Photochemical Smog is atype of smog produced when _______ from the sun reacts with __________ in the atmosphere.

Back 23

ultraviolet light

nitrogen oxides

Front 24

It is visible as a brown haze, and is most prominent during the morning and afternoon, especially in densely populated, warm cities.

Back 24

Photochemical Smog

Front 25

Photochemical Smog is visible as a ________, and is most prominent during the ________ and ________, especially in densely populated, warm cities.

Back 25

brown haze

morning

afternoon

Front 26

Gradual thinning of Earth’s ozone layer in the upper atmosphere caused by the release of chemical compounds containing gaseous chlorine or bromine from industry and other human activities.

Back 26

Ozone depletion

Front 27

Ozone depletion is the __________ of Earth’s ozone layer in the upper atmosphere caused by the release of chemical compounds containing gaseous chlorine or bromine from industry and other human activities.

Back 27

Gradual thinning

Front 28

Ozone depletion is the gradual thinning of Earth’s ozone layer in the upper atmosphere caused by the release of chemical compounds containing gaseous ________ or ________ from industry and other human activities.

Back 28

chlorine or bromine

Front 29

It is the long- term rise in the average temperature of the Earth's climate system.

Back 29

Global warming

Front 30

Global warming is the long-term rise in the ________ of the Earth's climate system.

Back 30

average temperature

Front 31

It is a major aspect of current climate change, and has been demonstrated by direct temperature measurements and by measurements of various effects of the warming.

Back 31

Global warming

Front 32

Global Warming is a major aspect of current ________, and has been demonstrated by direct temperature measurements and by measurements of various effects of the warming.

Back 32

climate change

Front 33

_________ processes create a range of air pollutants. Other pollutants of interest from these processes include:

• Organic acids

• Aldehydes

• Ammonia

• Carbon monoxide

Back 33

combustion

Front 34

Combustion processes create a range of air pollutants. Other pollutants of interest from combustion processes include:

Back 34

• Organic acids

• Aldehydes

• Ammonia

• Carbon monoxide

Front 35

________ is important to health simply because we spend too much time indoors, and the quality of the air we breathe is seldom monitored.

Back 35

Indoor air quality

Front 36

True or false:

Contaminated indoor air can cause any number of health problems, including eye irritation, headache, nausea, sneezing, dermatitis, heartburn, drowsiness etc.

Back 36

True

Front 37

Harmful Pollutants

Back 37

• Asbestos

• Carbon monoxide

• Formaldehyde

• Particulates

• Nitrogen oxides

• Ozone

• Radon

• Sulfur oxide

• Volatile organics

Front 38

AIR POLLUTION CONTROL

Back 38

✓ Control at source

✓ Controlling devices and technology

Front 39

Controlling devices and technology

Back 39

• Particulate pollution control

• Gaseous pollution control

Front 40

Control at Source

Back 40

• Source relocation

• Source shut down

• Fuel or Energy substitution

• Process changes

• Good operating practices

• Vehicular emission control

Front 41

It is the sum of all solid and liquid particles suspended in air, many of which are hazardous. This complex mixture contains for instance dust, pollen, soot, smoke, and liquid droplets.

Back 41

Particulate Matter

Front 42

Temperature and chemical composition of gases to be cleaned from particulants before the selection of proper control device.

Back 42

Particulate Matter Pollutant

Front 43

MAJOR GROUPS OF PROCESSES

Back 43

• Settling chambers

• Inertial separator or Cyclone

• Electrostatic precipitator

• Bag houses and filters

• Wet scrubbers

Front 44

The simplest device, collecting dust of size >100µ.

Back 44

Settling Chamber

Front 45

use the force of gravity to remove solid particles. The gas stream enters a chamber where the velocity of the gas is reduced.

Back 45

Settling Chamber

Front 46

Settling chambers use the force of gravity to remove solid particles. The gas stream enters a chamber where the velocity of the gas is _______.

Back 46

reduced

Front 47

Large particles drop out of the gas and are recollected in hoppers.

Back 47

Settling chamber

Front 48

True or False:

Because settling chambers are effective in removing only larger particles, they are used in conjunction with a more efficient control device.

Back 48

True

Front 49

The most popular, economical, and effective means of controlling particulates.

Back 49

Inertial Separator (Cyclone)

Front 50

➢ The dirty air is blasted into a conical cylinder, but off centerline.

➢ This creates a violent swirl within the cone, much like centrifuge.

➢ The heavy solids migrate to the wall of the cylinder, where they slow down due to friction, slide down the cone, and finally, exit at thebottom.

Back 50

Inertial Separator

Front 51

The particulate matter is removed by being charged by electrons jumping from one high- voltage electrode to the other and then migrating to the positively charged collecting electrode.

Back 51

Electrostatic Precipitators

Front 52

Widely used in power plants, mainly because power is readily available.

Back 52

Electrostatic Precipitators

Front 53

Operates like vacuum cleaner.

Back 53

Bag House and Filters

Front 54

In bag house and filter, ______ are used to collect the dust.

Back 54

Fabric bags

Front 55

______ are widely used in many industrial applications but are sensitive to high temperature and humidity.

Back 55

Bag filters

Front 56

Bag filters are widely used in many industrial applications but are sensitive to _______ and ______.

Back 56

high temperature

humidity

Front 57

The collection efficiency is very high and even for particle of 0.01µm diameter .

Back 57

Bag House and Filters

Front 58

The _________ remove dust from a gas stream by passing the stream through a porous fabric.

Back 58

Fabric filters or bag houses

Front 59

The Fabric filters, or bag houses , remove dust from a gas stream by passing the stream through a _________.

Back 59

porous fabric

Front 60

The objectives of scrubber is to entrain the particulate matter to the bottom of the scrubber, in liquid droplets.

Back 60

Wet scrubbers

Front 61

Water subsequently flows from the particulate is allowed to settle and clarified water is re- circulated.

Back 61

Wet scrubbers

Front 62

It is an effective method for removing large particulates.

Back 62

Wet scrubbers

Front 63

The waste is now in liquid form, and some manner of water treatment is necessary.

Back 63

Wet scrubber

Front 64

The removal methods for ________ are designed to concentrate the pollutants in a liquid (absorption) or a solid (adsorption).

Back 64

gaseous pollutants

Front 65

The removal methods for gaseous pollutants are designed to concentrate the pollutants in a ______ or a _________

Back 65

liquid (absorption)

solid (adsorption)

Front 66

Sometimes direct conversion of gaseous pollutants is possible by _________.

Back 66

combustion

Front 67

This processes is selected to remove gaseous pollutants by dissolution into a liquid solvent such as water or in a caustic or acid solution.

Back 67

Absorption

Front 68

This processes is selected to remove gaseous pollutants by dissolution into a liquid solvent such as water or in a

_______.

Back 68

caustic or acid solution

Front 69

Most commonly, _______ is used as an absorbent.

Back 69

water

Front 70

In absorption, as the gas stream passes through the liquid, the liquid absorbs the ______.

Back 70

gas

Front 71

It is commonly used to recover products or to purify gas streams that have high concentrations of organic compounds.

Back 71

Absorption

Front 72

Absorption is commonly used to recover products or to purify gas streams that have high concentrations of _________.

Back 72

organic compounds

Front 73

_________ is a process where gases, vapours or liquids are concentrated on a solid surface as a result of surface or chemical force (physical adsorption and chemisorption's respectively).

Back 73

Adsorption

Front 74

The adsorbed amount of substances depends directly on the __________ of solid and the ______ of the process.

Back 74

internal surface area

kinetics

Front 75

The most important adsorbents in industrial use to-days are ______, _______, _______, _______, and ______.

Back 75

Bauxite

activated carbon

activated alumina

silica gel molecular sieves.

Front 76

This method for the removal of VOCs since they can be decompose to CO2 and H2O.

Back 76

Combustion

Front 77

The direct and indirect or catalytic methods are used.

Back 77

Combustion

Front 78

In combustion, the direct and indirect or _______ are used.

Back 78

catalytic methods

Front 79

The _______ is preferred when low temperature of the process is desired.

Back 79

catalytic method

Front 80

The catalytic method is preferred when ________________ of the process is desired.

Back 80

Low temperature

Front 81

The most commonly used catalysts are the ____, _____, _____, and _____ compounds

Back 81

Cu, Ni, V and Zn

Front 82

True or False:

If the concentrations of air pollutants are high, a combination of sorption methods and catalytic reaction is used.

Back 82

If the concentrations of air pollutants are high, a combination of sorption methods and catalytic reaction is used.