The Role of Food Waste Disposers Joe Ferrara Dr Tim Evans

1. The Role of Food Waste Disposers Joe Ferrara Dr Tim Evans MD, InSinkEratorEurope Tim Evans Environment North East Recycling Forum 20th September 2012

2. About us UK trade association for the manufacturers of small and large domestic appliances World’s largest manufacturer of FWDs In 2010 members who manufacture FWDs formed AMDEA’s Food Waste Disposer Group AIM Promote greater awareness of the benefits of food waste disposers (FWDs) and contribute to efficient waste strategies.

3. What is an FWD? • Small device that fits under the kitchen sink • Grinds practically all food waste into minute particles (there are no sharp blades) • Carried away with the household waste water directly to wastewater treatment & anaerobic digestion (AD) plants where energy and fertiliser can be extracted

4. Why FWD? • Easy and hygienic option for citizens/users • Improve overall waste food diversion/capture • Require minimal education and persuasion • Lower collection and disposal costs • Cut kerbside collection vehicles • Reduce contamination of other recyclables • Strong evidence base • Good carbon footprint • Improve value capture: energy & fertiliser

5. UK - untapped potential Sustainable solution for Areas where peopleunable/unwilling to participate in separate kerbside collection or home composting: • High rise buildings • Terraced houses • Densely populated urban areas • Elderly or infirm

6. High usage abroad • 20% of Australian homes • 34% of New Zealand homes • 50% of US homes - Around 80% of new homes have a FWD and more than 80 municipalities require their installation as part of an overall environmental programme.  BUT Only used in about 6% of UK homes

7. Benefit - Efficiency • Food waste is separated quickly at the source • Capture more of this difficult waste stream than other solutions. • Easy & hygienic – eliminate the “yuck factor” - prevent contamination of other recyclables • Eliminate the bins that lure urban foxes and other vermin to doorsteps

8. Benefit - Reduce landfill • Can remove around 270 kilos of food waste per hshld per yr • Significantly reduce waste sent to landfill • Help authorities to meet zero waste targets Each tonne of food waste diverted from landfill and sent via FWDs to AD can save the planet 1 tonne of CO2e

9. Benefit - Good CO2 footprint • 2 – 3 kWh of electricity per hshld per yr = 37p yr • 6Ls of water per day = 1 extra toilet flush Each FWD creates 25 times more energy than it uses • Reduce traffic emissions & use of additional fossil fuel • At the end of life (approx 12 yrs) comprise primarily metal components & are 95% recyclable

10. Benefit - Energy capture FWDs enhance the extraction of sustainable value from waste.  • The food waste stream is rich in biogas • Most sewage sludge is processed by anaerobic digestion and increasingly both biogas and fertiliser are extracted • Food waste considerably increases the biogas/energy yield of sewage

11. Energy from waste

12. The Science Large body of scientific research…  • Environmental Impact for Herefordshire & Worcestershire County Council - Evans, T. D. (2007) - Global warming potential better than landfill, incineration or composting - Council saved £21 per household p.a. in 2005 • Life-Cycle Comparison of Five Engineered Systems, University of Wisconsin. January 1998-2002 - FWD has the lowest cost to the municipality - Most environmentally friendly option for recycling biosolids • Garbage Grinder Introduction - Sewage & Wastewater Dept, Hokkaido, Japan, 2003 - FWDs offer excellent cost benefits - Quality of treated water and amount of system water usage is unchanged • An Alternative to Separate Bio- Waste Collection? University of Karlsruhe, Germany, 2001 - FWD output is transported through sewers easily - Density and settling of bio-waste particles are much less than the mineral particles commonly found in sewer sediments http://www.food-waste-disposer.org.uk/the-science

13. Tim Evans’ background • Soil scientist [Newcastle upon Tyne and Madison, Wisconsin] • Thames Water – included creating environmentally controlled biosolids recycling for 6.5 million people • Independent consultant - mainly helping clients to sustainable solutions for organic residuals • Other activities: • EU Soil Strategy, Sludge Directive, Biowaste Directive, EoW criteria • British and European Standards, • Foundation for Water Research • Chartered Institution for Water & Environmental Management • European Water Association TIM EVANS ENVIRONMENT, Stonecroft, Park Lane, Ashtead, KT21 1EU, UK tim@timevansenvironment.com

14. Fundamentals • Legal obligation in EU to divert biodegradable municipal waste from landfill • Climate change • Phosphate crisis • essential for all life, • too precious to squander • People are individuals: one size won’t fit all whatever we might think is good for them

15. Kitchen food waste Is the most difficult fraction of municipal waste to manage 70% moisture content Biodegrades rapidly with high oxygen demand Prone to become putrid, smell and ooze leachate Flies maggots and vermin Home composting done well is great Many are unwilling or unable Source segregation and kerbside collection is good for those who are prepared to do it Participation rates are low in ”flatted” properties Physical contaminants in kerbside collected, source segregated biowaste [Germany, North America, UK found 12-20% w/w] FWD is also source segregation

16. Total household waste (from Parfitt, 2002) • Quested and Johnson (2009) • Local authorities in UK collect 5.8 Mt food waste • most of it is in the residual waste bins • equates to268 kg/hhd.yr

17. Inconvenient truth Flatted properties recycle less London Boroughs - correlation -0.529

18. Environmental Impact Assessment Herefordshire & Worcestershire (2005/06 data) Food waste collection + disposal = £18.63/hhd.year Food waste management GWP kgCO2e/t food waste

19. Cost transfer to waste water treatment • Herefore & Worcestershire audited data showed financial saving and good carbon footprint but what was the cost transfer to Severn Trent Water which is • 100% AD • target for 30% self-generated electricity by 2012 • welcomes extra substrate (biosolids to farmland) • Surahammar (SE) provided the answer • Influent monitored 4 weekly • FWD installation increased from 0% to 50% of households • Flow, ammoniacal-N, BOD7, COD did not increase • Biogas increased 46% (P=0.01)

20. Surahammar influent flow1995-2008 FWD installation started started Flow = hydraulic load perhaps ≈ water use