Materials For Greener Environment

50 %
50 %
Information about Materials For Greener Environment
Others-Misc

Published on October 2, 2008

Author: aSGuest410

Source: authorstream.com

Slide 1: Engineered Solutions International Rethinking the ‘Waste Hierarchy’ EurIng Ian M. Arbon MSc, MBA, CEng FIMechE, FASME, FEI, FInstR “Materials for a Greener Environment” 01 November 2005 IMechE HQ, London Slide 2: Engineered Solutions International EurIng Ian M. Arbon MSc, MBA, CEng, PE FIMechE, FASME, FEI, FInstR Rethinking the Waste Hierarchy 30+ years experience in delivering Energy from Waste Chairman – Energy, Environment & Sustainability Group – IMechE Chairman – Engineering Forum for Energy – ICE, IMechE, IEE, IChemE, CIBSE, EI Chairman – Renewable Power Committee, Power Industries Division – IMechE Distinguished Lecturer on “Renewable Energy & Sustainability” - ASME Slide 3: Engineered Solutions International Some Definitions Rethinking the Waste Hierarchy “’When I use a word’, Humpty Dumpty said in rather a scornful tone, ‘it means just what I choose it to mean – neither more nor less.’” - Through the Looking Glass (1872) In this presentation we shall also look at the meaning of some words: ‘waste’, ‘recycle’, ‘incineration’, etc. Slide 4: Engineered Solutions International Dictionary Definitions of Waste ‘Refuse from places of human or animal habitation’ ‘Anything rejected as useless, worthless, or in excess of what is required’ ‘Anything unused or not used to full advantage’ Rethinking the Waste Hierarchy Slide 5: Engineered Solutions International Other Definitions of Waste Rethinking the Waste Hierarchy “Any subject or object in the categories set out in Annex 1 of the Waste Framework Directive (91/156/EEC), which the holder discards or intends or is required to discard” - European Union “a resource that is not safely recycled back into the environment or the marketplace.” - ZeroWasteAmerica Slide 6: Engineered Solutions International Waste Arisings - UK Rethinking the Waste Hierarchy Slide 7: Engineered Solutions International Historical Analysis of Household Waste in UK Rethinking the Waste Hierarchy Slide 8: Engineered Solutions International Definition of the ‘Waste Hierarchy’ 1 – Reduce – 2 – Re-use – 3 – Recycle – 4 – Recover – 5 – Reject Rethinking the Waste Hierarchy Slide 9: Engineered Solutions International Definition of the ‘Waste Hierarchy’ 1 – Reduce (do not generate waste items) – 2 – Re-use (find another use for the same item) – 3 – Recycle (turn into a different item) – 4 – Recover (usually heat and power) – 5 – Reject (usually dispose to landfill) Rethinking the Waste Hierarchy Slide 10: Engineered Solutions International Analysis of the ‘Waste Hierarchy’ 1 – Reduce It would seem to be axiomatic that the best way of dealing with ‘waste’ is not to generate it in the first place! Despite the ‘hierarchy’ having been with us for many years now, waste arisings in the UK continue to grow at around 3% per annum, so it is clearly not achieving its primary objective of reducing wastage. Rethinking the Waste Hierarchy Slide 11: Engineered Solutions International Analysis of the ‘Waste Hierarchy’ 2 – Re-use The second priority, i.e. re-using items rather than throwing them away, is also highly commendable. Differs from “recycle” in that it finds another use for the same item, rather than changing it into a different item. “Re-use” is far easier to achieve in less developed economies than it is in a sophisticated, consumer-orientated society. We live in a “throw away, disposable” society and it may take several generations to change our thinking in this area. Rethinking the Waste Hierarchy Slide 12: Engineered Solutions International Analysis of the ‘Waste Hierarchy’ 3 – Recycle The third priority, “recycling” waste products, is not as straightforward as it might appear. Recycling involves the transformation (usually requiring energy input) of the waste product into another, different, product, e.g. the transformation of waste plastic cups into pens and pencils. Rethinking the Waste Hierarchy Slide 13: Engineered Solutions International Analysis of the ‘Waste Hierarchy’ 3 – Recycle (cont.) In some cases, the energy required in the recycling process (especially when separation, collection and transport are taken into consideration) is greater than the energy required to make the product from raw materials. This appears to be particularly true in the case of recycling paper: “It was disclosed last year that more than a third of Britain’s waste paper and plastic went to China for recycling.” – Daily Telegraph 18.07.05 Rethinking the Waste Hierarchy Slide 14: Engineered Solutions International Analysis of the ‘Waste Hierarchy’ 4 – Recover “recover” is regarded by many environmentalists as a ‘bad thing’ and the option of disposing to landfill will shortly no longer be available to us! On the other hand, many waste products can be excellent fuels for EfW plants where some of the energy that was expended in manufacturing the product in the first place is converted to electric power. Rethinking the Waste Hierarchy Slide 15: Engineered Solutions International Analysis of the ‘Waste Hierarchy’ 5 – Reject (disposal to landfill) Landfill sites consist of depositing waste in holes in the ground which is compacted and covered with earth. Different waste fractions decompose over different time periods and in the process produce carbon dioxide, methane and numerous other trace gases. If these gases are not collected and removed, they will either leak into the atmosphere or, in some circumstances, create explosive conditions in the landfill site. Dangerous liquids may also be discharged into the surrounding water table. Rethinking the Waste Hierarchy Slide 16: Engineered Solutions International Analysis of the ‘Waste Hierarchy’ 5 – Reject (disposal to landfill) The UK is reluctantly phasing-out landfill sites, partly because it is running out of suitable landfill sites and partly because of the European Landfill Directive (2002) which will require the organic fraction of landfilled waste to be reduced by 25% by 2010, 50% by 2013 and 65% (all below 1995 levels) by 2020. Rethinking the Waste Hierarchy Slide 17: Engineered Solutions International How is the UK doing? Rethinking the Waste Hierarchy Slide 18: Engineered Solutions International Is the ‘Waste Hierarchy’ working? As we have seen, the ‘Waste Hierarchy’ has some basic flaws: The first priority (Reduce) has to be contrasted with an annual growth in waste arisings of c.3% per annum. The second priority (Re-use) has had only limited success in a ‘throw-away’ society. The third priority (Recycle) has been given an artificial importance by recent legislation: Rethinking the Waste Hierarchy Slide 19: Engineered Solutions International CO2 Impact for Glass CO2 Saving kg/t Reduce c.843 Re-use 550 Re-cycle (closed-loop) – UK 314 Re-cycle (closed-loop) – Export 290 Re-cycle (open-loop) – Bricks 66 Re-cycle (open-loop) – Gl. Fibre 275 Re-cycle (open-loop) – Shot Blast 19 Re-cycle (open-loop) – Filtration -43 Re-cycle (open-loop) – Aggregates -2 Landfill Disposal 0 Rethinking the Waste Hierarchy ‘Waste’ Priority           Source: Oakdene Hollins and Enviros Slide 20: Engineered Solutions International Is the ‘Waste Hierarchy’ working? It is evident that blindly following current recycling legislation can lead to a situation which is absurd. Every example of ‘recycling’ needs to be analysed to ensure that the process is genuinely solving the problem (e.g. reducing CO2 emissions) and not exacerbating it. In any case, why should we continue to regard ‘waste’ as a problem; why not a ‘resource’? Rethinking the Waste Hierarchy Slide 21: Engineered Solutions International CO2 Impact for Glass CO2 Saving kg/t Reduce c.843 Re-use 550 Re-cycle (closed-loop) – UK 314 Re-cycle (closed-loop) – Export 290 Re-cycle (open-loop) – Bricks 66 Re-cycle (open-loop) – Gl. Fibre 275 Re-cycle (open-loop) – Shot Blast 19 Re-cycle (open-loop) – Filtration -43 Re-cycle (open-loop) – Aggregates -2 Landfill Disposal 0 Rethinking the Waste Hierarchy ‘Waste’ Priority           Source: Oakdene Hollins and Enviros ‘Resource’ Priority           Slide 22: Engineered Solutions International ‘Waste’ or ‘Resource’? Rethinking the Waste Hierarchy “The past 12 months have continued to show the denial and disconnected thinking with which the Government, businesses and the public approach the subject of waste. In this country, waste is seen as an end – a dead end – rather than a means. That view has to change.” “State of the Nation” Report - ICE (October 2005) Slide 23: Engineered Solutions International ‘Waste’ or ‘Resource’? Rethinking the Waste Hierarchy “Waste is a combination of materials – our resources for tomorrow. If we extract reusable materials, what’s left is residual waste – solid material containing energy that can be released to light rooms, heat buildings and drive businesses.” “State of the Nation” Report - ICE (October 2005) Slide 24: Engineered Solutions International ‘Waste’ or ‘Resource’? Rethinking the Waste Hierarchy “A report published by ICE and the Renewable Power Association measuring the potential energy from residual waste estimated that, by 2020, 17% of all electricity could, theoretically, come from waste. A more realistic but still very significant contribution would be 10%.” “State of the Nation” Report - ICE (October 2005) Slide 25: Engineered Solutions International In some cases, the energy required in the recycling process (especially when separation, collection and transport are taken into consideration) is greater than the energy required to make the product from raw materials. This appears to be particularly true in the case of recycling paper, for example. On the other hand, many waste products can be excellent fuels for EfW plants where some of the energy that was expended in manufacturing the product in the first place is converted to electric power. In each waste case, an energy balance should be made to calculate the net benefits of recycling or recovery. Isn’t it always better to ‘recycle’ than ‘burn’? Rethinking the Waste Hierarchy Slide 26: Engineered Solutions International Definition of ‘Incineration’ Having looked at the abuse in the UK of the English words ‘waste’ and ‘recycle’, let’s now look at the most misused word of all in this field: ‘Incineration’ All ‘Energy-from-Waste’ plants in the UK now, by law, regardless of the actual technology, must comply with the absurdly named ‘Waste Incineration Directive’! Rethinking the Waste Hierarchy Slide 27: Engineered Solutions International Most people in the UK do not know the difference between ‘incineration’ and ‘combustion’. The term ‘incineration’ stems from the outdated method of burning municipal solid waste (MSW) in order to destroy it. This thinking, in turn, derives from seeing waste as a ‘problem’ rather than as a ‘resource’; there is a particular issue here, in that the UK Government is itself very unclear on this subject! DEFRA constantly refers to EfW plants as ‘incinerators’ and despite public ‘consultation’ on this issue appears to have ignored the feedback! Is EfW a euphemism for Incineration? - 1 Rethinking the Waste Hierarchy Slide 28: Engineered Solutions International Incineration is the process of ”burning up completely” or “reducing to ashes” - i.e. the emphasis is on destruction of the material, or at least the organic fraction; Combustion is “the process of burning” or “any process in which a substance reacts to produce a significant rise in temperature and the emission of light” or “a process in which a compound reacts slowly with oxygen” – i.e. the emphasis is on the (chemical) reaction taking place in the process. Collins Concise Dictionary, Fourth Edition, Harper Collins,1999 Is EfW a euphemism for Incineration? - 2 Rethinking the Waste Hierarchy Slide 29: Engineered Solutions International Incineration is “a volumetric waste reduction process that relies on combustion under suitable controlled conditions to reduce the volume and/or mass of [waste] material for disposal” – i.e. the emphasis is on the disposal. Combustion is “a chemical reaction in which fuel combines with oxygen with the evolution of heat” – i.e. the emphasis is on the chemical reaction. Prof Andrew Porteous, Dictionary of Environmental Science and Technology, Third Edition, John Wiley & Sons, 2000 Is EfW a euphemism for Incineration? - 3 Rethinking the Waste Hierarchy Slide 30: Engineered Solutions International Examples of modern Energy-from-Waste (EfW) Plants. If these are Incinerators… Rethinking the Waste Hierarchy Slide 31: Engineered Solutions International …then please describe this as a Coal Incinerator! Drax Coal-Fired Power Station, North Yorkshire – 3,400 MW from largely imported fossil fuels. Rethinking the Waste Hierarchy Slide 32: Engineered Solutions International Peterborough Gas-Fired CCGT Station – 380 MW from increasingly imported fossil fuels. … and this as a Gas Incinerator! Rethinking the Waste Hierarchy Slide 33: Engineered Solutions International Direct Combustion Most developed countries recognise the important contribution which can be made to EfW by the simplest, cheapest and, often, most efficient method of energy conversion, i.e. Direct Combustion. Modern combustion plants have overcome most of the problems associated with older ‘incinerators’ and it is strange indeed that it is not included among the Advanced Conversion Technologies (ACT)! From a technical standpoint, this makes no sense whatsoever and this situation should be urgently reviewed. State-of-the-art in energy conversion - 1 Rethinking the Waste Hierarchy Slide 34: Engineered Solutions International Heat Feed Steam turbine Direct combustion Solid organic fuel Components: boiler, steam turbine Proven technology Highly reliable State-of-the-art in energy conversion - 2 Rethinking the Waste Hierarchy Slide 35: Engineered Solutions International Some European examples of Direct Combustion: State-of-the-art in energy conversion - 3 Rethinking the Waste Hierarchy Slide 36: Engineered Solutions International 2) Pyrolysis Pyrolysis is the thermal degradation of organic waste in the absence of oxygen to produce a carbonaceous char, oils and combustible gases. Although pyrolysis is an age-old technology its application to biomass and waste materials is relatively recent. An alternative term for pyrolysis is thermolysis, which is technically more accurate for waste energy processes because these systems are usually starved-air rather than the total absence of oxygen. Although the future for pyrolysis is extremely promising, there is as yet little direct operating experience with this method. State-of-the-art in energy conversion - 4 Rethinking the Waste Hierarchy Slide 37: Engineered Solutions International Pyrolysis Feed solid organic fuel absence of oxygen thermal degradation State-of-the-art in energy conversion - 5 Rethinking the Waste Hierarchy Slide 38: Engineered Solutions International State-of-the-art in energy conversion - 6 Compact Power Pyrolysis/ Gasification System Rethinking the Waste Hierarchy Slide 39: Engineered Solutions International Gasification Gasification differs from pyrolysis in that oxygen in the form of air, steam or pure oxygen is reacted at high temperature with carbon in waste to produce a gas, ash or slag and a tar product. Although gasification is very recent in its application to waste, coal gasification of coal, is well proven. Major benefit of gasification is that product gas is used directly to fuel a gas turbine generator which forms part of a CHP or CCGT system, improving overall thermal efficiency. Main disadvantage is high capital investment and lengthy pay-back periods. State-of-the-art in energy conversion - 7 Rethinking the Waste Hierarchy Slide 40: Engineered Solutions International Gasification Solid organic fuel / gas from pyrolysis Partial oxidation Fuel gas: CO / CO2 / CH4 / H20 Reduced NOx / dioxin formation State-of-the-art in energy conversion - 8 Rethinking the Waste Hierarchy Slide 41: Engineered Solutions International State-of-the-art in energy conversion - 9 Global Olivine High Temperature Combustion/ Gasification System Rethinking the Waste Hierarchy Slide 42: Engineered Solutions International (Anaerobic) Digestion (AD) AD is commonly used with liquid and semi-liquid slurries such as animal waste; it is also used for obtaining gas from human sewage but is now being applied to certain biomass wastes. Digestion utilises the same biological processes as a landfill but under controlled conditions in a digester system, which is a warmed, sealed, airless container where bacteria ferment organic material in oxygen-free conditions to produce biogas. Amount of biogas is limited by the size of the digester tank so is used as fuel in a gas boiler or in an engine to generate electricity. State-of-the-art in energy conversion - 10 Rethinking the Waste Hierarchy Slide 43: Engineered Solutions International Digestion Liquid organic fuel Anaerobic CH4/CO2 fuel gas State-of-the-art in energy conversion - 11 Rethinking the Waste Hierarchy Slide 44: Engineered Solutions International Typical Digester Systems State-of-the-art in energy conversion - 12 Rethinking the Waste Hierarchy Slide 45: Engineered Solutions International The growing problem of Waste which cannot be landfilled. PREP can handle all of these! Proposed Peterborough Renewable Energy Plant Rethinking the Waste Hierarchy Slide 46: Engineered Solutions International Proposed Peterborough Renewable Energy Plant Rethinking the Waste Hierarchy Slide 47: Engineered Solutions International Proposed Peterborough Renewable Energy Plant Rethinking the Waste Hierarchy Slide 48: Engineered Solutions International Typical Fuel Input for PREP (1 million t/y): Industrial/Commercial Waste 410,000 t/y Municipal Solid Waste (MSW) 300,000 t/y Sewage Sludge 90,000 t/y Vehicle Tyres 30,000 t/y Oil/Thinners (after recycling) 20,000 t/y Locally-grown Biomass 150,000 t/y Proposed Peterborough Renewable Energy Plant Rethinking the Waste Hierarchy Slide 49: Engineered Solutions International Normal Annual Outputs: 126 MW Electric Power NETT! (>1.0 TWh) Up to 58,000 m3 Concrete 145,000 t Aggregates – block products 2,500 t Non-ferrous metal ingots 30,000 t Iron & Steel 50,000 t Glass Products (tiles, filtration, enamel etc) 12,000 t Hydrochloric Acid Up to 4000 tonnes Pure Sulphur Up to 2 tonnes Pure Mercury 725,000 MWh Renewable Obligation Credits 1,300,000 tonnes Carbon Credits ZERO output to landfill! Proposed Peterborough Renewable Energy Plant Rethinking the Waste Hierarchy Slide 50: Engineered Solutions International Will PREP ever be built? After 5 years of immensely hard work, we seem to have made hardly any progress. Often we feel like giving up but we are encouraged by the thoughts of Mahatma Gandhi: “First they ignore you, Then they laugh at you, Then they fight you, Then you win!” Rethinking the Waste Hierarchy Slide 51: Engineered Solutions International Rethinking the ‘Waste Hierarchy’ Thank you for your attention during this presentation. Rethinking the Waste Hierarchy “Materials for a Greener Environment” 01 November 2005 IMechE HQ, London

Add a comment

Related presentations

Related pages

Advanced Materials for Sustainable Energy and a Greener ...

The world today is very different from how it once was. The consumption rate of fossil fuels compared to the available resources and the calamity of global ...
Read more

Energy Harvesting for a Greener Environment Introduction

Energy Harvesting for a Greener Environment Introduction Energy Harvesting (EH) is the process of electronically capturing and accumulating energy from
Read more

Advanced Materials for Sustainable Energy and a Greener ...

Read "Advanced Materials for Sustainable Energy and a Greener Environment" on DeepDyve - Instant access to the journals you need!
Read more

Tabib - For a Greener Environment

Tabib: For a Greener Environment. The National Company for the Treatment and Disposal of Toxic Waste, Ltd.
Read more

Environmentally friendly - Wikipedia, the free encyclopedia

Environmentally friendly or environment-friendly, (also referred to as eco-friendly, nature-friendly, and green) are marketing and sustainability terms ...
Read more

Environment - Apple

We’re switching to greener materials to create safer products and ... Safer Materials ... More answers to your questions about Apple and the environment.
Read more

Advanced Materials for Sustainable Energy and a Greener ...

Advanced Materials for Sustainable Energy and a Greener Environment on ResearchGate, the professional network for scientists.
Read more

Design for Environment - Dell

At Dell, we are committed to making smarter choices about the materials that go into our products. There are two sides to this commitment: using ...
Read more

MATERIAL RESOURCES, PRODUCTIVITY AND THE ENVIRONMENT: KEY ...

1 Material Resources, Productivity and the Environment Key Findings 1. Establishing a resource efficient economy is central to greening growth
Read more

Sustainable Marketplace: Greener Products and Services ...

The greener products site will educate manufacturers, consumers, institutional and Federal purchasers on greener products and sustainable acquisition.
Read more