www.cranfield.ac.uk

Methane from waste:emission sources & solutions

Prof. Phil LonghurstChair of Environment & Energy Technology

Tuesday, 20th March 2018, European Parliament

a brief overview, the main sources, feasible options for mitigation

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Methane from waste… so what?!!

• 2015 waste emitted 193,313 kt CO2 eq.

• ~200 billion tonnes

• CO2 eq. emissions from waste shows

the largest reduction (42%, 1990-2015)

amongst major contributors

• Landfill directive

• Waste Framework Directive

• Landfill Directive

• IPPC Directive

• Directive on Industrial Emissions

So, is there a problem...?0

50000

100000

150000

200000

250000

300000

waste - emissions kt CO2 eq.

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• In Europe we use 16 tonnes of

material, per person, per year

• 6 tonnes becomes waste

• In 2010, EU waste was a total of

2.5 billion tonnes

• Only 36% was recycled with

the rest landfilled or burnt

• So, waste management is vital in

reducing CH4 emissions Eurostat (2014) EU-28 (%)

Waste per capita, 2005 and 2016, (kg per capita)

20052016

No significant reduction in municipal waste in kg per capita (2005-16) - despite increasing focus on recycling

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~22% = biodegradable wastes

Rapid & slow anaerobic formation of CH4

• Bio-waste = garden and park waste, food and kitchen

waste from households, restaurants, caterers and

retail premises, waste from food processing plants.

• Organic = forestry or agricultural residues, manure,

sewage sludge.

• Degradable = natural textiles, paper, woodEurostat (2014)

EU-28 (%)

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Biogas – approx. composition

Gas Formula Approx. % vol

Methane CH4 50-70

Carbon Dioxide CO2 25-45

Oxygen O2 <2

Nitrogen N2 <2

Ammonia NH3 <1

Hydrogen H2 <1

Hydrogen Sulphide H2S <1

Water H2O 2-5

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Controlling the biogas chain – managing wastes

CollectionRecyclates /

reuse

Market preparation

reprocessing

residue Disposal landfill

‘Soil’

‘fuel’

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Case example: What can be achieved?

Targeted biogas regulation of landfill sites of 12x sites

• 12x environmental regulators, targeting sites with

existing infrastructure, by:

• Teaching the basic aspects of landfill gas

management.

• 2x groups with 12x site visits;

• Teaching material development;

• Expert guidance – with university collaboration;

• Targeted operator resources to improve landfill gas

collection

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CO2 equiv. @ a conservative 40% v/v CH4 gas =

Results

• Increased collection by 7,600 m3/hr of landfill gas

within 12 months

• 19,022 tonnes of CH4 / yr, previously emitted to the

atmosphere

• 2005 data shows 927,000 tonnes pa for UK, i.e.

a 2% reduction by the group (Kyoto Protocol, Defra)

• GWP = 399,456 tonnes of carbon dioxide (t CO2e)

• > 6x the total carbon dioxide emissions for the

Environment Agency - England & Wales in 2006/7 (65,018 tonnes IEM Easinet page)

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Key processes & sources

Priority areas

• Anaerobic digestion processes – preventing residues to landfill

• Biowaste exclusion from landfill

• Food waste

• Materials contaminated with organics

• Sewage sludge

• Landfill operation and closure

• Site management & regulation

• Infrastructure costs as gas revenue declines

• Climate change impacts on landfills

• flooding or land-slide

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Future challenges

• Population growth

• Increases in waste

• Economic limits to recycling

• Complex products

• mixed material packaging

• Degradable vs non-degradable mix

• Declining rates of landfill gas production

• Economic viability of gas collection

• Disposal of sites

• Changes in site ownership / insolvency

• Climate change impacts - vulnerable sites

– flooding, land-slide with large CH4 loss

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towards a European methane strategy

A pathway for mitigation

• Maximise separation of organics

• degradable & non-degradable material wastes

• Increased attention to landfill

• degradability of material inputs

• Technology & global market development for passive management of landfills

• Targeted regulation focussed on maximising gas extraction & management

• Data sharing and monitoring of sites along with their estimated emission potential

• Targeted focus and survey of landfills for climate change impacts

• estimated a total of 150-500k sites across EU

• vulnerable sites – flooding, land-slide with potential for large CH4 losses

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www.cranfield.ac.uk

Prof. Phil LonghurstChair of Environment & Energy Technology

p.j.longhurst@cranfield.ac.uk

+44 1234 754953 / +44 7904 157404