Post-consumer plastic wastes

Post-consumer plastic waste recycling is discussed with special reference to feedstock recycling, the advantages it has over mechanical recycling, and the techniques involved. Chemolysis and thermolysis are explained, and... 

Examples of mixed post-consumer plastic waste by the combination of a three-stage sink-float method and selective flotation have been presented. The appropriate conditions, e.g., wetting agents, frother, depressant, and pH condition, are of importance (122). 

S. Pongstabodee, N. Kunachitpimol, and S. Damronglerd, Combination of three-stage sink-float method and selective flotation technique for separation of mixed post-consumer plastic waste, Waste Manage. (Oxford), 28(3) 475—483,2008. 

W. Ding, J. Liang, and L.L. Anderson, Thermal and catalytic degradation of high-density polyethylene and commingled post-consumer plastic waste. Fuel Process. Technol., 51, 47 (1997). 

Poly(ethylene terephthalate), PET, has become one of the major post-consumer plastic wastes. PET products do not present a direct threat to the environment, but they do pose a problem of considerable concern due to the huge amount of solid waste produced [1]. The disposal of this waste together with its low bio-degradability and photo-degradability, now represents a serious challenge for industrial countries worldwide. 

Khait, K., Recycling of post-consumer plastic waste via new solid-state shear extrasion pulverization process, Proceedings Polymer Processing Society and American Instimte of Chemical Engineers joint meeting, Chicago, 11-14 Nov 1996. 

R. Ball and A. Unsworth, Markets for Post Consumer Plastics Waste in proceedings of R 95, Geneva, Switzerland, 1, pp. 281-286 (1995). 

Automated sorting of post-consumer plastic waste was achieved using a combination of fixed-filter NIR and neural network data analysis. Rapid and reliable identification of polymers can be made. The effectiveness of the method was demonstrated for sorting PET, HDPE, and PVC (261). 

However, in order to expand the recovery and recycling of plastics and decrease the amount of waste disposed in landfills, it will be necessary to overcome these difficulties. Because of its heterogeneous nature and the amount of contaminants present, separation of post-consumer mixed plastic waste is the most difficult. Waste plastics from industrial operations are cleaner and more homogeneous in resin type and scrap form than postconsumer plastics. The term "mixed plastics" has been used to describe broad scale processing of post-consumer plastic waste, although no formal definition yet exists. In its broadest sense, mixed plastics means a collection of a mixture of plastic resins or a mixture... 

Nir M. M. (1990), Recycling Implications of Post-consumer Plastic Waste , Plastics Engineering, 21-28, October. 

Mechanical Recycling of Post-consumer Plastic Waste... 

Mechanical recycling of post-consumer plastic waste makes economical, ecological and social political sense only if an efficient system of collecting and sorting the waste has been well conceived and implemented. 

Polystyrene (PS) is an important fraction of post-consumer plastic waste. PS and expanded polystyrene (EPS) are extensively used in packaging, hence PS recycling is important. The processing stability of EPS packaging material is shown in Fig. 12. Addition of a sterically hindered phenol, Irganox 245, to compacted EPS allows to maintain the average molecular weight of the polymer at a level sufficient for EPS-processes [16,17]. 

Khait, K. (1996) "Recycling of post-consumer plastic waste via new solid-state shear... 

Although in a number of countries incineration of plastics is not acceptable because of the public opinion, we believe that incineration with energy recovery is a better solution, for the present at least, than other processes such as reducing to monomers the post consumer plastic waste. In Japan where the public have accepted incineration, a great number of incineration plants have been in operation. Our company alone has constructed more than 20 fluidized bed incineration plants since 1981. The incineration must meet the following conditions ... 

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