1 E nvironmental consequences of combustion processes – Part II (Global Warming) Dr. Hassan Arafat Department of Chem. Eng. An-Najah University (these.

1

Environmental consequences of combustion processes – Part II

(Global Warming)

Dr. Hassan ArafatDepartment of Chem. Eng.

An-Najah University

(these slides were adopted, with modification, from Ms. Paulina Bohdanowicz , KTH Institute, Sweden)

CHAPTER # 4CHAPTER # 4

2

What is a Green House?

Greenhouses are much warmer inside than the air is outside because the glass is transparent to light and allows short-wavelength light to pass through and heat the contents of the greenhouse. It also reflects back the longer wavelength heat radiating within the greenhouse, thus preventing if from passing back out.

3

Greenhouse Effect In A Greenhouse

4

What is Green House Effect?

• In a glass greenhouse, heat builds up and gets trapped due to presence of carbon dioxide and other heat trapping gases in the upper atmosphere.

• CO2 is analogous to glass.• Earth’s surface analogous to floor

which radiates back absorbed energy as longer wave infrared heat.

5

The greenhouse effect

Atmosphere

Greenhouse gases

Long wave heat radiation

Short wave radiation

6

The greenhouse effect• History

– Natural greenhouse effect– Enhanced greenhouse effect

• Mechanism– GHG:

• H2O vapour

• CO2

• CH4

• O3

• N2O

• CFCs• HCFCs

• HFCs• PFCs

• aerosols

7

Green House Effect

• Does Greenhouse effect cause warming of the earth’s surface?

•YES!, for without a greenhouse effect due to gases in the atmosphere, the average temperature of the earth’s surface would be 00F.

•Earth’s surface temperature is about 600F due to greenhouse effect.

8

Global Warming

• Pollutants from a small area can accumulate and spread in the upper atmosphere and affect entire earth’s weather

• increase in CO2 is resulting in increase of earth’s temperature

• can result in melting of ice caps, coastal flooding, shift in weather patterns, etc.

9

Greenhouse Gases

Gas SourcesAbsorption range,

m

Residence

time,year

RIRF GWPContribution to

rel. GWP

H2O vapour

Natural processes

2.5-3.5, 5-7, > 13

CO2

(365ppmv)

Natural processes HC combustion

4-4.5, 14-19 (15-16)

50-200 1 1 57-60 %

CH4

(1.77ppmv)

Organic Matter decayHC combustionNatural processes(Ice deposits)

3-4, 7-8.5 12 43 21 12-20%

O3 Natural processes 9-10

N2O (312 ppbv)

Microbial processesAgriculture Waste and sewage dumpsHC combustion

3-5, 7.5-9

120 250 310 6%

CFCs & HCFCs (1-2ppbv)

Only anthropogenic 8-12 60-

1000015000-19000

1000-1000

0

14-25%

10

Atmospheric CO2

Figure 3.6 Change in atmospheric carbon dioxide at Mauna Loa Observatory,Hawaii. (Source: White, 1990)

11

Global Carbon Emissions from Fossil Fuel Burning, 1751-2002

0

2,000

4,000

6,000

8,000

1751 1801 1851 1901 1951 2001Source: ORNL, BP

Mill

ion

Ton

s

Carbon data include only fossil fuel related emissions. They exclude emissions from cement manufacture.

12

13

The concentration of the three most important greenhouse

gases

14

Effects of Major Greenhouse Gases on Global Warming

Percent contributionGas to global warming

Carbon dioxide 57

Chlorofluorocarbons 25

Methane 12

Nitrous oxides 6

15

Contribution of CO2 Toward Global Warming

Activity Percent contribution

Energy use 49

Industrial processes 24

Deforestation 14

Agriculture 13

16

Human influences on the carbon-cycleCombustion of fossil fuels and deforestation are the most important anthropogenic sources for CO2 emissions to the atmosphere

Fossil fuels• Oil• Natural gas• Coal

Oceanic uptake

Forest regrowth (0.5)

Fertilization effect (2.0)

Tropical Deforestation (-1.5)

6.06.0 1.51.5 2.52.5 2.02.0

Atmosphere +3 GtonC/yr (+1ppm/yr)

((GtonC/yrGtonC/yr))

17

Carbon Emissions Per Person in Selected Countries, 2002

0

2

4

6

Sources: ORNL, BP, IEA, DOE, LBL, IGU, Census Bureau

Ton

s of

C

arb

on

18

-

1.00

2.00

3.00

4.00

5.00

6.00

0 1,000 2,000 3,000 4,000 5,000 6,000

Population (million)

Em

iss

ion

s (

ton

car

bo

n p

er

cap

ita)

USA

Canada, Australia, New Zealand

Japan

OECD Europe

Russia

Other Europe

China

Middle East

IndiaOther Asia Africa

Latin America

World Average

CO2-C emission per capita, 1998

2 Gt C/yr

10 billion people

0.2 ton C/capita per yr

19

Annual precipitation pattern has changed

Source: www.ipcc.ch

20

Annual temperature pattern has changed

Source: www.ipcc.ch

21

Global warming

• Consequences of increased CO2 levels– Enhanced

photosynthesis & plant growth

– Increased plant water use efficiency

– Reduction of susceptibility to several environmental stresses

– Increase in biodiversity

– Increase in acidity of oceans

• Consequences of global warming– Melting of ice caps– Increase in ocean levels– Coral bleaching– More severe weather

conditions– Plant life – loss of

biodiversity– Gulf Stream?– Global warming kills

about 160,000 people through its effects every year

22

1979

2003

National Geographic Magazine

September 2004

+

23

Söndre Strömfjord, Greenland, 1985

The glacier fronts are retreating.

24

Melting glaciers

25

Number and Cost of Weather-Related Disasters, 1980-2003

0

30

60

90

120

1980 1985 1990 1995 2000

Source: Munich Re

Billio

n Do

llars

(2

002

Dolla

rs)

0

200

400

600

800Num

ber of Events

Economic Losses

Disasters

26Vogel, G.: Science 297, Aug. 23 2002 Scott, R.C. 1996

27

Weather-related disasters

28

Weather-related disasters

29

What Can We Do?

• Reduce World’s Population? • Reduce or maintain current levels

of CO2 in the atmosphereR ed u c tion in C arb on D ioxid e

in c reas in g th e rem ova l o fa tm osp h eric ca rb on d ioxid e b y p lan ts

red u c in g carb on d ioxid eem iss ion s in to th e en viron m en t

R ed u c tion incarb on d ioxid e

30

Kyoto Protocol• Rio Earth Summit 1992• United Nations Framework Convention on

Climate Change (UNFCCC):• Intention to reduce atmospheric concentrations

of greenhouse gases• Nonbinding agreement, affecting 40

industrialized countries (annex I)

• Kyoto 1997• Third conference of the parties• Kyoto protocol: treaty that fixes targets and

timetables for the annex I countries• Ratified by Russia on November 18, 2004 • Came into force on February 15, 2005

31

Present status of the USA

• Responsible for 25% of CO2 emissions• Did not ratify the Kyoto Protocol• Calling for a further involvement of developing

countries, in particular China and India• ”Economy would be affected too much” &

”American lif style is not a point of discussion”• Kyoto Protocol is ”fatally flaved”• Aim to stabilize emissions• In 2002 left the international negotiations• Measures on state level• 12% increase between 1990 and 2001