Destination-process-specific Optimization of Waste Processing Using Innovative Treatment Technology

Published 2009

Citation: Ragossnig A. Destination-process-specific Optimization of Waste Processing Using Innovative Treatment Technology, ISWA Annual Congress 2009, 12th-15th of October, Lissabon, Portugal.

Abstract

Driven by increasing energy and raw material prices as well as changes in the legal framework the state of the art in the European Union has changed from waste management to resource management over the past 15 years. This has led to a higher appreciation of the resource “waste” as a secondary raw material as well as an energy resource. In this context the importance of effective waste processing in order to allow quality specific routing of waste streams has become very important. On the one hand material recycling requires a high purity of the waste material to be recycled. The prices to be achieved for the recycling material are highly dependend on the purity of the recyclables. The economic viability of treatment concepts very much depends on the rate of recovery of the recycling product. On the other hand the portion of waste that is thermally treated has increased and still is on the rise. Furthermore extensive efforts on the usage of waste fractions as Solid Recovered Fuels (SRF) in alternative thermal treatment processes with higher energy recovery are being undertaken. Alternative thermal treatment
processes have special demands on the quality of the waste streams to be treated due to process and product quality reasons as well as ecological concerns. Sophisticated waste pre-treatment concepts ensure compliance with required quality standards of wastes to be recycled or utilized energetically. In spite of that waste pre-treatment - in sometimes complex processes - the problem of disposal of the remaining residual waste fraction has to be solved, as the disposal of the residuals in compliance with the regulatory framework causes high expenses for the waste treatment plant operator. The first part of this manuscript focusses on the legal framework prompting the implementation of new waste processing technologies allowing an effective routing of waste fractions by material specific splitting of the over all waste stream. Most relevant in that respect are the EU Waste Framework Directive as well as the EU Landfill Directive and the EU Packaging Directive. Climate
policy and respective regulations are also influencing waste management practice. Additionally economic aspects for destination-process specific routing of waste streams are being addressed. In the second part of this manuscript the set-up of test runs as well as the results obtained and experiences gained based on the test runs are being reported. One test set-up aims at removing highcaloric waste components from waste streams of Mechanical-Biological Treatment (MBT) facilities in order to maximize the quantity of waste that can be landfilled. A second test set up deals with the processing of commercial plastic waste containing different types of polymers in order to gain pure recyclables. As the economic value of waste plastic depends on the purity in terms of individual polymers it is very important to separate individual polymers from mixed plastic waste. Near-Infrared
(NIR) sensor based sorting allows a separation of different types of plastics. The results of test runs are explained in terms of quality and yield of product gained as well as economical aspects. Although the prices for recyclables have fallen during the last months as a result of the financial and economical crisis leading to a decrease in the demand of recyclables it is assumed that gaining high quality waste fractions from mixed wastes for material recyling as well as energy recovery will become more important in the long run.