Preface
Waste quantities are on a continually-increasing trend and the waste business is prospering. This is particularly true for several specific kinds of wastes. In an affluent society such as ours, in the industrial world a large quantity of surplus goods is produced in manufacturing and distribution processes and ultimately in households. This overabundance has to be dealt with and disposed of and thus WASTE is produced.
Waste incorporating both valuable materials and harmful components.
Waste frequently constituted by still marketable goods capable of providing sustenance to the less affluent.
Waste that reflects the lavish mindset of our society.
Waste capable of providing new resources by direct use, recycling or following some kind of treatment.
Waste that may help to save our natural resources.
Waste capable of harming the environment when disposed of under uncontrolled conditions.
Accordingly, the BOKU Waste Conference 2009 pursues an intra-disciplinary approach in discussing the current problems with growing prosperity wastes with regard to technical, economical, environmental, social, and political aspects. Thus, participants are afforded an excellent opportunity to extend their main emphasis gradually, focusing on new, comprehensive perspectives in an attempt to envisage potential approaches for future application.
WEEE - drain or gain? - High-tech treatment versus resource losses of valuable materials
- The session focuses on current treatment strategies for wastes containing both valuable and harmful components, such as waste electrical and electronic equipment (WEEE) and end-of-life vehicles (ELV), and provides a critical appraisal of the technical and non-technical approaches of how to cope with the problems.
Increasing costs of raw materials and widening gaps between technological standards underlie a striking phenomenon: Valuable wastes from Europe are either treated at a considerable cost using high-end processes or lose their marketability, being treated elsewhere by means of scarce or in the lack of technical and social standards. E.g. it is estimated that the bigger part of Belgian end-of-life cars are sold and shipped to Africa, the Middle East and other regions. On the other hand treatment processes in Europe are getting more and more sophisticated, mechanised, efficient, but also expensive.
These issues give rise to numerous questions. From an economic point of view, a potential resource shortage should be prevented in order to maintain valuable materials on the economic market. From a social point of view, environmental harm by low-tech treatment abroad should be limited. From a technical viewpoint, improved efficiency with regard to cost reduction, ecology and social aspects may be fundamental.
Food and Food Wastes - The session focuses on economic, ecological and social problems with edible food waste and scrutinise prevention measures, waste management options, case studies, social aspects and political decisions. It wants to create awareness - on technical, behavioural, political as well as social level.
Food is an essential part of our life as it covers physiological (e.g. nutrient supply), social (identity, communication), cultural (taboo, values) and psychological (pleasure) functions. The supply of food for human consumption implicates numerous research activities (biotechnology) and considerable efforts in production (manpower, energy, soil, water, knowledge), processing (energy, knowledge, packaging), distribution (energy) and trade (stockyard, energy). Indeed, food represents one of the most demanding products from a point of view of energy and resources. Moreover, food frequently features as a central theme in connection with ethics as well as social and environmental responsibility - as is the case with hunger, Fair Trade and organic food issues.
Nevertheless a large quantity of still edible food is disposed of during all stages of production, distribution and usage. The majority is constituted by leftover food still suitable for human consumption. In addition to the social and ethical issues, considerable efforts are required in the correct handling of food residues in waste management. An unthinkable amount of edible food waste is landfilled worldwide and converted into methane. Thus, the high quality food produced in compliance with strict legal restrictions continues to contribute towards global climate change even at the end of life cycle.
Utilization and testing of MSWI bottom ash - The session focuses on the latest technical and legal developments on pretreatment, utilization and testing of municipal solid waste incineration (MSWI) bottom ash and similar inorganic residues.
Although in many countries metal-containing waste streams, like waste electrical and electronic equipment (WEEE), are already separately collected or sorted, a considerable amount of these components still remains in the residual solid waste worldwide. The residual waste is often directly landfilled, pre-treated (e.g., mechanically-biologically) or combusted in incineration plants.
The amount of MSWI bottom ash from waste incineration in Europe currently exceeds 10 Mio t. Landfilling of bottom ash is a common practice in many EU countries, but landfill space is restricted. Reactions and heat formation in landfills are crucial, and the long-term behaviour under specific landfill conditions are often unknown, since the development of key parameters depends on the access of C02 . Due to its technical properties, bottom ash may be utilized as a building material in road construction. Further, substantial amounts of iron, copper and aluminium are present in bottom ash in their metallic form, making recovery of these metals economically attractive.
My thanks to the ABF-Team and to Gerry for organising this conference and producing this book.
Peter Lechner
April 2009