1. SustainableEngineering@Edinburgh Sustainable Waste Management By Sustainable Waste Management By: Shane Doolin (0840441); Patricia Lehane (0837208); Gerard Noone; Jonathan Walker; Group Number 9 IMS3 Sustainability Module, 26th March 2009 Introduction The average human uses 45-85 tonnes of materials each year. The aim of the Waste Management Hierarchy is to move as close as possible to the top of the hierarchy by minimising the waste generated, reusing waste materials, recycling, and, where this is not possible, disposing of waste in ways that unlock or recover energy, for example in waste-to-energy treatment plants Prevention Industry, business and government are adopting the ideas of industrial metabolism, industrial ecology, ecodesign and ecolabelling to make use of materials more sustainable. Environmental and social costs fall on those who cause them (Polluter Pays) Concept of zero waste, technical cycle composed of 100% reusable materials called technical nutrients designed in such away that they can remain in closed loop systems throughout their life cycle. Use of financial incentives References “Sustainable Waste Management” Audit Scotland AGS/2007/7, www.audit-scotland.gov.ukwww.audit-scotland.gov.uk Scottish Planning Policy SPP 10- August 2006 Planning for waste management: Consultant draft “Thermal waste treatment for sustainable energy” ICE journal of engineering sustainability(2007) Vol: 160, Issue: ES3 Reduce, Reuse, Recycle The 3 R’s represents the “waste hierarchy” which lists the best ways of managing waste from the most to least desirable. Reduce Not producing waste in the first place is the obvious solution and we can all play a part by thinking about how and why we produce waste. Reuse Choosing to buy reusable items also helps to reduce waste and protect the environment. Recycle Waste products can be turned back into the raw materials they came from and then used to make new products. This method helps to: - Save the earths natural resources - Save energy and reduce the risk of climate change - Reduce the need for landfill Energy Recovery Waste-to-Energy Plants Waste-to-Energy plants use waste as an alternative resource to produce sustainable energy In 2005 in the UK, 150k tonnes of MSW were thermally treated It is not the answer to all waste problems. It is designed only to treat residual waste that remains after waste prevention, re-use & recycling programmes. However, in this role, waste-to-energy can recover renewable energy from a waste material that is otherwise lost to landfill. Non-Recyclable fraction of MSW combusted under controlled conditions to produce steam that powers a turbine generator. Net electricity derived from 1 tonne of MSW (about 500-650kWh) avoids mining 1 third of a tonne of coal or importing 1 barrel of oil Landfill Landfills are sites for the disposal of waste materials by burial and are the oldest form of waste management. Historically landfills have been the most common method of organised waste disposal and remains globally. Biodegradable waste has the potential for adverse environmental impacts through the emission of climate changing greenhouse gases, especially methane. However the collection and use of methane from landfills can significantly reduce the overall emissions of green house gases. As landfills are the largest anthropogenic source of methane in Europe it is logical to implement gas recovery systems, which may generate electricity or through enrichment sold to gas pipelines. The 2007 “EU Framework Directive on Waste”, short term goals state to ‘Reduce landfill of biodegradable waste by local authorities to 1.5 million tonnes per year’ and long term outlooks to ‘Reduce landfill of municipal waste from 90% to 30%.’