Title: Recycling of plastics

Authors: G . Menges, H. Emminger, G. Lackner

Addresses: RWTH-Aachen, Germany. ' RWTH-Aachen, Germany. ' RWTH-Aachen, Germany

Abstract: Plastics are composed of macromolecules in the same way that living creatures in nature are. Nature should therefore be employed as an example for these materials. A brief review is given of the recycling methods that are being applied to other construction materials, as well as a presentation and discussion of the methods applied to plastics and the benefits involved. In order to show the current state in the discussions, the German situation is taken as an example here. Since Central Europe is particularly overcrowded, this situation is very oppressive. The methods under review are divided under certain aspects. The criteria are first, which sort of waste is producted (pure or mixed), second, the class of materials and, third, the physical or chemical method employed. Also economic efficiency is being estimated for all the cases following the latest research results. Finally, an innovative consideration is introduced which is based on the principles of nature, in a way following the example of nature by technical means. Mixed plastics waste, which can barely be recycled, is being burnt at very high temperatures applying pure oxygen. Concerning this method, some experience is at hand. Since only carbon monoxide, carbon dioxide and water emerge, this mixture is submitted to a process of technical reforming, which is usual in steamcracking. The carbon is thus regained from its oxidic compound by means of recycling techniques, i.e. by means of generating hydrocarbons which can then be reused as fuel or raw material for new polymers of the carbon compound, which indeed is a valuable material, nothing at all merges into the environment. This is also true for carbon dioxide. In a universal balance it is shown that, following the proposal made by a German inventor, in an enterprise integrating the generation of power, energy and of this technique can even be efficient from the economic point of the fact that such an integral plant is capable of exploiting the heat process stages to a particularly high level.

Keywords: carbon cycle; energy; mixed plastics waste; plastics recycling; plastics reuse; environmental pollution; Germany; hydrocarbons.

DOI: 10.1504/IJMPT.1991.036640

International Journal of Materials and Product Technology, 1991 Vol.6 No.4, pp.307 - 330

Published online: 05 Nov 2010 *

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