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Environment and

Sustainability

Robert Field

goods, services and waste

some basic material and energy concepts

the role of engineers

Lecture 1: Engineers and the

environment

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Learning outcomes of this course

To acquire knowledge and understanding of

1. The concept and consequences of sustainable

development: social, environmental and

economic.

2. The changing role of engineering in sustainable

development.

3. The tools used to implement sustainable

design.

Engineering is

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Engineering is the knowledge required,

and the process applied, to conceive,

design, make, build, operate, sustain,

recycle or retire, something with a

significant technical content for a specific

purpose: a concept, a model, a product, a

device, a process, a system, a service, a

technology.

Royal Academy of Engineering

Why should you care?

1.

2. Political environment requires it?

3. Helps win contracts?

4. Helps avoid prosecutions?

5. Long term nature of engineered solutions?

"In the whole history of technology it would be difficult to find a greater single

advance than this, nor one with a greater significance for all humanity". Rolt.

Credit: Wikipedia

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Plentiful supplies of cheap energy (wood, then coal)

fuelled the industrial revolution

Widnes, mid-

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Civil,

mechanical,

control,

electrical and

chemical

engineering at

Stanlow cat

cracker

produces

automotive

fuel from oily

residues.

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The

engineered

environment.

M2 motorway

and Eurostar

train crossing

the River

Medway in

Kent.

Natural

Ecosystems &

Agriculture

Industrial

Production

Human

Society

(after Clift R, Trans Inst Chem Eng B2 151 1998)

Resource flows Solar

energy

Waste

Emissions

to air and

water

Emissions

to air and

water

Emissions

to air and

water

Emissions

and

dispersed

residues

Goods &

Services

Food &

Products

Non-renewable

Resources

Sustainable development?

The early history of modern sustainable development:

World Conservation Strategy (WCS): published in 1980 by the World

came to prominence;

World Commission on Environment and Development 1987: aka. The

Brundtland Report. This developed the key principles and ideas;

G7 Toronto summit of 1988: This was where the major industrial

nations, including the UK, signed up to the concept;

The Earth Summit in Rio in 1992: this produced the Rio Declaration of

Intent with Agenda 21 as the implementation action plan.

The Bruntland definition

From the Brundtland Report (1987)

Development that meets the needs of the

present without compromising the abilities of

future generations to meet their own needs

Principle is known as intergenerational equity

Traditional SD concept

Economy

Society

Environment

SD

Robust SD concept

Environment

Society

Economy

The economy operates within the

limits of society which flourishes

within the limits of nature.

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US Material Flow

US Economy: only 6% of materials flow ends in products

Computing waste: Laptop ~ 4,000 times; microchip ~ 100,000 times

1 tonne paper consumes 98 tonnes of various resources

US industry handles ~ 1,800 tonnes per year per average household

Total waste flow (inc waste water) > 100 x 109 tonne per year,

Less than 2% recycled

Materials flow per average American : 56 kg/day

(21 fuel; 21 construction materials; 7 farm products

2.7 forestry; 2.7 industrial minerals; 1.4 metals)

PLUS: 1,000 kg water and 170 kg rock

(tailings, overburden, waste water from fuel and minerals extraction)

One lecture theatre chair...

Steel for hinges made from pig iron (each tonne of steel produces

quantities of slag and a steel mill uses 20kg of coal to make steel for

one chair);

Iron ore mining produces waste, land originally forested etc;

Chrome-plating wastes;

Plastics products of oil industry spills fears.

(Leather seat tannery pollution.)

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Working material balances- an example

The mass of the atmosphere is about 5 million Gt. What is the

carbon inventory of the atmosphere, if the current

concentration of carbon dioxide is 388 ppmv?

5 million Gt is 5 x 1018 kg air

with a molecular weight of 29, this is equivalent to

5 x 1018 / 29 = 0.172 x 1018 kmol

Assuming ideal gas behaviour, then the volume

fraction is equal to the mole fraction, and so

CO2 inventory is (388 x 10-6) x 0.172 x 1018 kmol

= 66.7 x 1012 kmol

1 kmol of CO2 contains 1 kmol of carbon, so the

carbon inventory of the atmosphere is

66.7 x 1012 x 12 kg = 800 Gt C

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Global population, billion

0

1

2

3

4

5

6

7

8

9

10

1860 1880 1900 1920 1940 1960 1980 2000 2020 2040 2060

Sources: World Energy Council; World Bank; D. Bice, Carleton College MN; US Census bureau

Human Development Flows of Resource

Global water consumption, km3/y

Global energy consumption, Gtoe/y

Annual usage

Oil: 5 km3

Fresh Water: 5000 km3

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A little thermodynamics!

1. 2nd law - heat cannot be wholly converted into work

2. C + O2 CO2 H = -393.5 MJ kmol-1

H + O2 H2O H = -142.9 MJ kmol-1

3. 1 kWh = 3.6 MJ

boe (barrel of oil equivalent 1 boe = 6.12 GJ)

toe (tonne of oil equivalent 1 toe = 45.37 GJ)

tce (tonne of coal equivalent 1 tce = 28.84 GJ)

(these are higher heating values)

The boiler house can be 220m long, 60m high,

and 55m wide. The boiler walls are made of 51

km of 62.5 mm bore tubing. Inside the tubes,

extremely pure water is boiled at high

pressure, and then super-heated to 568

degrees Celsius. A 500 MW boiler can consume

over 200 tonnes of coal per hour, and is

capable of delivering 25 tonnes of steam each

minute at a pressure of 197 bar.

Conversion of fossil fuels

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Coal: Direct combustion, 90% to heat only,

Conversion of fossil fuels

20 DECHEMA

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Main source: BP Statistical Review of World Energy 2010

34.64

29.25

23.68

6.61

5.45

0.26 0.07 0.05

Oil

Coal

Gas

Hydro

Nuclear

Wind

Solar thermal

Geothermal

2009 Primary energy supply, by type, % Total is 11.2 Gtoe (~16TW)

1 toe = 41.868 GJ

Biofuels are omitted

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Primary energy consumption and

production, 1998

Source http://www.ourplanet.com/aaas/

Linear to circular

The Linear Economy

Resources

Production

Consumption

Waste

Ecosystems

Resources

Production and

consumption

Waste

Soil Organic

matter

Ecosystems

Leaf fall and

decay

Nutrient

uptake and tree

growth

The ecological model 2

Duck Doo

Nutrients

(plus CO2 and H2O)

Microbial

decomposition

Consumption

Inputs of solar

energy

Resources

Production

Consumption

Waste

(Renewable)

Energy

The ecological model 3

The ecological model 4

The

economy

Biological nutrients

Technical nutrients

Energy

The planet

The sun

Pros & cons of the ecological model

Pros Potential for genuine sustainability

Mature eco-systems are a working model

Resistant to rebound effects

Cons

Weaker economic driver, although it has intrinsic efficiencies (eg:

recycling 1 aluminium can saves energy equivalent to a 100W bulb

running for 20 hours)

Rebound effect: eg commuting

0

20

40

60

80

100

120

140

160E

ne

rgy

GJ

pa

Normal Car Efficient Car Efficient Car & Flight

Indirect Rebound Effect

Direct Rebound Effect

Base Consumption

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The Mark I engineer, 1859

The bridge at Saltash

Box tunnel (2.9 km) on the GW Railway

IK Brunel at the

launching of the

Great Eastern

The mark 1 engineer: the man* who

made an economic return on capital invested

delivered product fit for purpose of client

unrecognised or accepted as an inevitable part of

progress (~100 fatalities at Box Tunnel).

The mark 2 engineer also

complied with health and safety legislation

applied techniques to quantify or mitigate HSE

impacts (HAZOP, BATNEEC, etc)

* Women hardly featured in engineering at the time these views were

current. The terminology of mark 1,2 and 3 engineers was suggested by

Prof R Clift.

Mark 1 and Mark 2 Engineers

But what of the future?

The mark 3 engineer must consider the

needs of society, as well as economic and

environmental impacts. Welcome to the

world of sustainable engineering!

Minority Report DreamWorks

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Acknowledgement

Professor Darton is thanked for his development on the

lectures on Sustainability; 60% of the material has been taken

from the lectures that he gave in previous years.

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References and Suggested

Reading

Our Common Future, World Commission on Environment and Development 1987, ISBN 0-19-282080 OUP

The New Model Engineer and Her Role, R Clift Trans IChemE

Vol 76, Part B 151- May 1998

Engineering, Ethics and the Environment, PA Vesilind and AS

Gunn ISBN 0-521-58918-5 CUP

Clean Production Strategies, Tim Jackson (Ed) 1993, ISBN 0-

87371-884-4 CRC Press LLC

Isambard Kingdom Brunel, LTC Rolt 1970 Penguin

BP Statistical review of World Energy (web downloads)