Fakulty of Forestry, Geo and Hydro Sciences, Institute of waste management and contaminated site treatment

WASTE TO ENERGY PLANTS AS AN OPPORTUNITY FOR ENERGY PRODUCTION TO SUBSTITUTE FOSSIL FUELS AND TO AVOID GREENHOUSE GAS EMISSIONS Dr.-Ing. Christoph Wünsch Prof. Dr.-Ing. Bernd Bilitewski

Mauritius, Wednesday 7th September 2011

Contents

1. Waste incineration – Why? 2. Energy recovery from waste incineration 3. Release of greenhouse gas emissions 4. Avoidance of greenhouse gas emisions 5. Substitution of fossil fuels 6. Summary and conclusion

Mauritius, 07.09.2011

Waste to energy plants as an opportunity for energy production to substitute fossil fuels and to avoid greenhouse gas emissions

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Waste incineration – Why? −

treatment in sanitary landfill gas can reduce GHGemissions to up to 75 %

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mechanical, biological and/or thermal treatment lowers GHG- emissions additionally

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primary target of waste incineration plants is the environmentally compatible disposal of wastes

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secondary target is the recovery of energy

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use of electrical power and heat/cold results in a further decrease of GHG-emissions

Mauritius, 07.09.2011

Waste to energy plants as an opportunity for energy production to substitute fossil fuels and to avoid greenhouse gas emissions

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Energy recovery Direct use as process steam or district heat or with 30 % efficiency as district cold

Energy in electrical power: app. 22 % net

Up to 70 % thermal and 10 % electrical in CHPgeneration

Energy in Flue gas: 13 %

Energy in Watersteam-cycle: 85 %

Energy in waste: 100 %

Energy in Slag: 2 % Mauritius, 07.09.2011

Waste to energy plants as an opportunity for energy production to substitute fossil fuels and to avoid greenhouse gas emissions

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Energy recovery −

town/area with 1 million people producing 200 kg MSW/a with a caloric value of 9,000 kJ/kg thermal power: 60 MW or 500.000 MWh/a

thermal input in MWh/a

net efficiency factor Energy output in MWh/a

Thermal

85 %

425.000

Electrical power

22 %

110.000

70 %

350.000

10 %

50.000

500.000

CHP thermal CHP electrical power

Mauritius, 07.09.2011

Waste to energy plants as an opportunity for energy production to substitute fossil fuels and to avoid greenhouse gas emissions

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Release of GHG-emissions −

released climate relevant carbon dioxide depends on incinerated amount of fossil fixed carbon

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amount is influenced by the following waste characteristics: - incinerate type of waste - composition of the differend fractions in the waste - biogenic/fossil portion in the type of waste - carbon content of the type of waste - efficiency of combustion

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for MSW in industrial countries between 0.253 and 0.557 Mg CO2,f/Mg MSW were calculated 1 million people

50,600 Mg CO2,f/a released

200,000 Mg/a Mauritius, 07.09.2011

Waste to energy plants as an opportunity for energy production to substitute fossil fuels and to avoid greenhouse gas emissions

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Avoidance of GHG-emissions

GHG-emissions factor in Mg CO2/Mg fuel calorific value in MWh/Mg fuel GHG-emissions factor in Mg CO2/MWh fuel electrical net efficiency substitution factor power in Mg CO2/MWh power thermal net efficiency substitution factor heat in Mg CO2/MWh heat Mauritius, 07.09.2011

lignite

hard coal

light fuel oil gas

1.101

2.455

3.169

1.865

2.941

6.98

11.836

9.392

0.374

0.352

0.268

0.199

30 %

35 %

35 %

40 %

1.248

1.005

0.765

0.496

85 %

85 %

85 %

85 %

0.44

0.414

0.315

0.234

Waste to energy plants as an opportunity for energy production to substitute fossil fuels and to avoid greenhouse gas emissions

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Avoidance of GHG-emissions

GHG-emissions in million Mg CO2,äq /a

0,05 lignite

hard coal

light fuel oil

natural gas

0,00

-0,05 -0,055 -0,084

-0,10

-0,099 -0,111 -0,134

-0,15

-0,137

-0,148

maximum heat output

-0,176

-0,20

-0,107

-0,195

-0,178 -0,217

-0,25

maximum power output maximum CHP heat output maximum CHP power output

- greenhouse gas balance by adding 50,600 Mg CO2,f/a Mauritius, 07.09.2011

Waste to energy plants as an opportunity for energy production to substitute fossil fuels and to avoid greenhouse gas emissions

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Substituted fossil fuels 0,197

substituted fossil fuels in million Mg/a, million m 3 (natural gas)

0,20

maximum heat output 0,170

maximum power output maximum CHP heat output maximum CHP power output

0,15 0,125

0,10 0,079 0,072 0,045

0,05

0,042

0,047 0,027

0,057

0,053 0,029

0,00 lignite

Mauritius, 07.09.2011

hard coal

light fuel oil

Waste to energy plants as an opportunity for energy production to substitute fossil fuels and to avoid greenhouse gas emissions

natural gas

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Summary and conclusion −

high organic content in MSW of developing and emerging countries release low amounts of climate relevant GHGemissions during incineration

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with high energy recovery rates, high amounts of primary fossil fuels can be saved additional climate relevant greenhouse gas emissions can be avoided

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modern waste incineration plants are expensive and well trained and very experienced people are necessary

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integration of waste incineration plants in power supply systems with a high recovery rate of heat, combined with the production of electrical power !

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use of produced energy leads to a reduction of the payback period for the investment Mauritius, 07.09.2011

Waste to energy plants as an opportunity for energy production to substitute fossil fuels and to avoid greenhouse gas emissions

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Thanks for your attention Contact: Christoph Wünsch Institut für Abfallwirtschaft und Altlasten Pratzschwitzer Str. 15 01796 Pirna Tel.: +49 3501 530044 E-Mail: [email protected]

Mauritius, 07.09.2011

Waste to energy plants as an opportunity for energy production to substitute fossil fuels and to avoid greenhouse gas emissions

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Mauritius, 07.09.2011

Waste to energy plants as an opportunity for energy production to substitute fossil fuels and to avoid greenhouse gas emissions

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