Bahir Dar University

7/31/2019 Bahir Dar University

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SCHOOL OF

COMPUTING&

ELECTRICAL

ENGINEERING

1

BAHIR DAR UNIVERSITY(IOT)


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Group Members2

Addisu Feyissa.079/2001

Alem Hailu...117/2001

Andinet Fikadu.168/2001Birhanu Girma..315/2001

Biruk Teshome..326/2001Delelegn Zeleke377/2001

Desalegn Gibtsu395/2001


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Contents3

Introduction

Formation of Fossil Fuels

Types of Fossil FuelsFossil Fuels in Ethiopia

Use of Fossil fuels

Problems in using Fossil FuelsConclussion

i l


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Energy Conversion & RuralElectrification

4

Project 1

Servay of National

Fossil Fuels


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1. Introduction5

Our World has so many energy sourses. e.g energyfrom the sun,wind and falling water.

We can also get energy from materials which arefound under ground that contain stored energy.

These stored energy sourses are known as FossilFuels (it took million of years for fossil fuels tocome to be).

Becouse of so long time to be formed again, most

geologists feel that little or no new fossil fuel isbeing produced.

For this reason, we call fossil fuels "are

nonrenewable" energy sources.


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Contd6

By digging out the deposited energy sources andburn them, we can get useful energy.

Electric power generation has to be applied on Fossil

Fuels before any use. Fossil fuels are the dominant sources of primary

energy in the world economy.


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2. Formation of Fossil Fuels7 Fossil fuels are found deposited in rock formations.

They were formed between 350 million and 650million years ago.

The processes by which they formed are not totallyunderstood.

Decayed remains of ancient plants and/or animalswere buried by sediments.

Through the action of heat and pressure over millionsof centuries, they were chemically changed.


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Contd8

These sediments exerted pressure one on the otherfor thousands of years:-results heat.

Through the action of heat and pressure over

millions of centuries, they were chemically changed:-chemical reaction takes place.

Decayed remains of ancient plants or animals wereburied (covered) by sediments and form layers as

they sank under the water of swamps.


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3.Types of Fossil fuels9

Because of they have been formed from theorganic remains of prehistoric plants and

animals, this implies that fossil fuels areindirect form of chemically stored energy.

The main constituents of fossil fuels are

1. Crude Oil2. Natural gas

3. Coal


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Crude Oil10

Oil is found in beds of sedimentary rocks.

It is account for the largest share in theworlds primary energy.

There are so many consumers of oil.

Among them the transport sector will beincreasingly important as a consumer of

oil. The share of final energy consumption of

oil is rising from 47% in 2002 to 54% by2030 according to world energy out look.


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contd11

In the developing economies, the demand for oil will risenot only because of transport, but also the following needs.

consumption in the industrial

residential

services sectors The growth of oil supply is 77 million barrels per day in

2000 to 121.3 million barrels per day in 2030 (IEA 2004).

Volatility in oil prices can be occasioned by the impact ofsevere weather conditions on offshore supplies, industrialstrife impacting on short-term supplies, the threat ofterrorist strikes against oil infrastructure, and politicaluncertainties in producing regions like the Middle East,Russia, Central Asia, Venezuela and Africa


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Natural gas12

Natural gas is composed primarily of methane (CH4). Itdoes contain other chemical species, such as butaneand propane.

It has much to offer as an energy source that makes itpreferable to other forms of fossil fuels.

It burns much cleaner than coal or oil, and it producesless carbon dioxide for each unit of energy.

Initially, it was used for lighting in homes andbuildings.

The increased production of electricity to day led to adecline in this usage, although there became a growingdemand for its use to heat homes, water and cook.


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Contd13

Its simple chemical nature makes it a much bettersource to use in high efficiency fuel cells thaneither coal or gas

As a usable energy source, natural gas really has

only one stumbling block, but it is a major one.

it is hard to transport and store.

If the transport or storage system is not completely

sealed, natural gas will leak. These problems have kept natural gas from

widespread usage throughout history, even thoughits existence has been known about for a long time.


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Coal14

Coal resources are vast and widely distributedaround the world.

. This gives coal a major advantage, from an energy-

security perspective, over other fuels. . However, only some of these resources are

economically recoverable using current technology.

Nonetheless, using estimates of proven coal

reserves (coal that is both technologically andeconomically recoverable), todays worldreserve base represents more than 200 yearsof current production.


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Contd15 The outlook for coal production and supply costs is

subject to less uncertainty than are those for oil andgas.

Continued productivity gains should result in some

further cost reductions. While coal plants have relatively high capital costs, fuel

costs are low relative to natural gas and coal plants willremain highly cost-competitive in the most efficient

coal producing regions of the advanced economies. The biggest uncertainty for the coal industry concerns

demand, which in turn is heavily dependent on howcoal-combustion technologies develop in response to

environmental worries.


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3.Fossil Fuels in Ethiopia16

Energy is needed as an input in industry, agriculture,mining, construction and service-givingorganization.

Ethiopia is one of the countries that depend uponimported petroleum products.

The yearly import of petroleum products isabsorbing more than one third of Ethiopias annual

exporting products. The need of domestic fuel in the country is the major

factor for deforestation and soil degradation.


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Contd17 Inter-Trappean coal and oil shale deposits are distributed on

the South-Western and Central Plateau of Ethiopia:-

1. Delbi-Moye

2. Yayu

3. Lalo-Sapo4. Sola and Chida

5. Chilga,

6. Nejo,

7. Mush Valley The intra-cratonic Ogaden Basin (Eastern Ethiopia) and Blue

Nile Basin (Central Ethiopia) covers an area of 350,000 kmand 120,000 km2, respectively.


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18


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Delbi-Moye Basin19

Delbi is found 390 km west of Addis Ababa, and 48km south of Jimma.

The basin is located between 2060 and 2240 meters

above sea level. A total of 25 boreholes were drilled in the Delbi-

Moye Basin.

It consists of the lower basalt, lower

sedimentary formation, middle basalt, uppersedimentary formation, upper basalt andacidic to intermediate volcanics.


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Yayu20

Yayu is 564 km from Addis Ababa along Jimma-Bedle Gambella road or 500 km along Nekemte-Bedle-Gambella road.

The basin is found between 1300 and 1700 m abovesea level.

A total of 100 boreholes were drilled in the YayuBasin.

A total of 200,000,000 tones of coal depositsestimated in the Yayu Basin.


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Chilga Basin21

Chilga is located 52 km southwest of Gonder.


12 boreholes were drilled in the central part of thebasin.

The Chilga coal reserve is estimated to be 19, 700,000 tones.


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Nejo basin

22

Nejo is located 190 km west of the town of Nekemte.


The area consists of Precambrian basement rocks,Tertiary sediments and Tertiary volcanics.

The total reserves coal in the Nejo area is estimatedto be 3 million tones


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Mush valley23

Mush Valley is situated 159 km northeast of AddisAbaba along Addis Ababa-Dessie road.

The area is found between 2600-2800 m above sea

level. The Inter-Trappean coal-bearing lacustrine

sediments predominantly composed of sandstones,siltstones, carbonaceous shales and coal seams.

Two coal seams are interbedded at different levels inthe coal-bearing sediments.


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Wuchale area24

Wuchale is 62 km from Dessie along Addis Ababa-Mekele road.

The area is found between 2067 and 3560 m abovesea level.

The total reserve is estimated to be 3.3 milliontones.


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How to generate electricity25

The chemical energy stored in solid fuel is used togenerate steam.

This steam then drives turbine that drives agenerator to produce electricity.

This process takes stored chemical energy to kineticto electrical energy. This is similar to the way that

power can be harnessed using hydro-electric andwind turbines.

Types of fossil fuel electricity generation facilities

commonly found


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Contd26

i. steam cycle facilities (commonly used for largebase load facilities);

ii. open cycle gas turbines (commonly used formoderate sized peaking facilities);

iii. cogeneration and combined cycle facility (thecombination of gas turbines or internal

combustion engines with heat recoverysystems); and

iv. internal combustion engines (commonly used

for small remote sites or stand-by (emergency)eneration .


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5.Use of Fossil fuels

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Coal is crushed to a fine dust and burnt.

Oil and gas can be burnt directly


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Coal-Fired Steam Cycle28

The characteristics and composition of coal varymore than those for other fuels commonly used inelectricity production).

Ash is also extracted from the bottom of the boiler(bottom ash).

Ash is transported to ash dams as a slurry, densephase (paste), or dry. Fly ash from some power

stations can be used as a resource, such as blendingwith cement.

Ash is composed of modified coal mineral matter,i.e. primarily compounds of silicon, aluminum,

iron, calcium, manganese, potassium, sodium and


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Contd29

The major emissions to air include carbon monoxide(CO), oxides of nitrogen (NOx), sulfur dioxide (SO2),emissions of metals (usually reported as metal &compounds for the NPI),organic compounds, carbondioxide (CO2) and water vapour.

Carbon dioxide and water vapour are not NPIsubstances and are not reported to the NPI.


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Gas and Oil-Fired Steam Cycle30

A major difference between coal-fired facilities andgas or oil-fired facilities, is that gas and oil facilities

burn the fuel with minimal on-site processing beforecombustion.

Generally, they do not have control equipment tocollect particulate matter, as emissions of particulatematter are low for gas and generally low for oil.

Emissions to air include carbon dioxide (CO2), watervapour, oxides of nitrogen (NOx), carbon monoxide(CO), minor emissions of metals and metalcompounds and organics, and sulfur dioxide (SO2)

for oil firing.


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Contd31

Fig. over all flow diagram for a steamcycle facility


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6.Disadvantages of Fossil Fuels

32 Carbon Monoxide. Carbon monoxide (CO) is a

product of incomplete combustion of any fuel. It is

both a highly poisonous gas and the principalconstituent of photochemical smog

Sulfur Oxides. Sulfur oxides arise duringcombustion from oxidation of sulfur in sulfurcontaining

fuels (some coals and some petroleum-basedproducts). The principal product is sulfur dioxide:

S (in fuel) + O2 SO2


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Contd33

Nitrogen Oxides. Nitrogen oxides have twosources.Fuel NOxis produced when nitrogen atomschemically combined with the molecules of the fuelare oxidized during the combustion process to form

nitric oxide: 2 N (in fuel) + O2 2 NO

Unburned Hydrocarbons. Unburnedhydrocarbons represent another source of air

pollution associated with the use of fossil fuels(especially gasoline), even though they are not aresult of combustion.

Greenhouse Effect

social and economic effect


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7.How to solve the problem

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reduce capacity or close down the plant;

reduce emissions by installing scrubbers orswitching to low-sulfur fuel;

purchase emissions allowances from companies(electric power plants, primarily) that exceed their

emission reduction goals.


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8.Conclusion35

The Ethiopian coal and oil shale deposits occur betweentwo volcanic flows. The coal and oil shale-bearingsedimentary basins in Ethiopia are one of the strikingexamples of an Inter-Trappean continental

sedimentation. Proximate and calorific value analysis results revealed

that the Ethiopian coal deposits range from lignite-bituminous coal.

The coal measures of Ethiopia belong to tertiary andminor amounts of Mesozoic age. Various geochemicalstudies were carried out to determine the physico-chemical characteristics of the Ethiopian coal deposits.

Oil and gas deposits possibly plays major role in the

future energy budget of Ethiopia.


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Contd36

The coal and oil shale deposits of Ethiopia can beused for

as a substitution firewood.

production of oil and gas.

to relieve the pressure on using wood as fuel forsmall-scale industries.

gasification of lignite to produce chemicalfertilizers.

the low-medium volatile bituminous coals of Moyearea used to produce coking coals for smelting of

iron.


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Recommendations37

Extracting of Fossil fuels is very expensive, so thegovernment should invest funds on the extracting ofthese sources and open access for foreign investors.

There should be educated power in the field studyingabout fossil fuels and other natural resources.

The government should give special attention fornational resources because, The yearly import of

petroleum products is absorbing more than one thirdof Ethiopias

annual exporting products.

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