ISSN:0258-0322    

DOI:10.1002/masy.19920570103

出版商:Hüthig&Wepf Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractEnvironmental concern about waste problems and regulatory measures from the governments have increased during the last decade. Plastics waste management has become a major strategic issue for the European plastics industry.A statistical study provides data on plastics consumption, post‐users plastics waste arisings based on a life‐time analysis and plastics recovery in the year 1989. An end‐use sectorial split‐up into sectors like municipal solid waste, automotive waste, agricultural waste, construction, as well as large distribution waste, will serve as a base for an integrated plastics waste management concept including recycling of mono‐material and co‐mingled waste, chemical recycling, energy recovery and landfill.An overview gives examples for ongoing plastics recycling activities in Western Europe and an outlook to the year 2000 i

ISSN:0258-0322    

DOI:10.1002/masy.19920570104

出版商:Hüthig&Wepf Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractIn Japan, full‐scale waste plastic recycling business started around 1970. Since then, in parallel with the efforts to develop new uses of recycled products, remarkable progress has also been made in recycling/molding technologies. The most popular recycling/molding technologies applicable to thermoplastics are of melt‐and‐mold type. This presentation discusses the technologies in their present situations, economics and existing disadvantages. The quality standards are set for some recycled products, the relations among recycling technologies, products' physical properties, and quality standards. Among others, explanations are given of waste‐derived solid fuel manufacturing technologies, incineration technologies paired with thermal energy recovery currently av

ISSN:0258-0322    

DOI:10.1002/masy.19920570105

出版商:Hüthig&Wepf Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractAn increasing awareness of ecological problems will enhance all activities towards recycling of polymers. In other words, we have to expect a fast increasing amount of recycled polymers. Today, most activities concentrate on the economical feasible part of recycling ‐ waste of higher prized plastics, only slightly contaminated plastic waste.Public pressure and legislation request solutions for heavily contaminated commodity plastics from household waste as well. The strategy to produce thick walled, profiles out of comingled plastics will be a contribution towards, but not the solution of the problem. We have to make the serious attempt to separate specific polymers like PE, PS, PET from the waste and to introduce these recyclates into the plastic market. In other words, we have to establish closed loops for all our products. Tremendous problems lay ahead of us in order to accomplish it. We need markets for recyclate, we have to change specifications accordingly, we have to improve existing technologies for work up, we have to develop “raw material” specifications when we turn waste in an economic good, we have to develop scenarios for unsufficient economics.The paper will deal with all these aspects in detail and will discuss the present situation in Ge

ISSN:0258-0322    

DOI:10.1002/masy.19920570106

出版商:Hüthig&Wepf Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractThe technology of separating plastics from the municipal waste stream for reuse is reviewed, with emphasis on the key role played by the bottle sorting step. Experience gained in the first year's operation of two large commercial recycling plants provides a better understanding of practical problems encountered, their relative importance, and technical advances needed for improved operation. It is concluded that purity of feedstock and processing rate are two critical independent variables requiring technical and business understanding and management. Hypothetical examples illustrate the interplay of these with dependent variables of yield and sorting cost.

ISSN:0258-0322    

DOI:10.1002/masy.19920570107

出版商:Hüthig&Wepf Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractMixed Poly(vinyl chloride) (PVC) and Poly(ethylene terephthalate)(PET) scraps can be separated by various methods based on the difference in their physical or chemical properties. A short review of the presently known methods is made. The presentation is focused on a method developed by MICRONYL WEDCO and based on the difference in impact strength resistance of the two polymers at room temperature.

ISSN:0258-0322    

DOI:10.1002/masy.19920570108

出版商:Hüthig&Wepf Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractA two‐step process has been developed in order to renovate highly photodegraded polymers. It was applied to clear and pigmented commercial PVC plates, which were exposed to accelerated weathering. The brown highly degraded top layer was first removed by sandpapering, which makes the color disappear and restores the original impact resistance of PVC. In a second step, a thin film of a UV‐curable acrylic resin was sprayed onto the PVC plate, which thus recovered its initial transparency. After a 1s UV exposure, the coated PVC was found to exhibit an excellent resistance to chemicals, weathering and scratching. One of the distinct advantages of this new low‐cost recycling process is that it is based on existing technologies and can be carried out directly on the plastic structures to be reno

ISSN:0258-0322    

DOI:10.1002/masy.19920570109

出版商:Hüthig&Wepf Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractPlastic films are used for mulching of cotton in the Seville area of Spain. A programme to recycle this type of mulch film was initiated. The different aspects studied were the collection system, the recycling technology and the applications of the recycled material.The long strips of films made transportation difficult. Size reduction and washing were found to be the most critical steps in the recycle process. The reason for this were the high toughness of the film on the one hand and the high level of soil contamination on the other hand. This soil contained up to 3% of iron, a polyethylene prodegradant.

ISSN:0258-0322    

DOI:10.1002/masy.19920570110

出版商:Hüthig&Wepf Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractA great amount of plastics are present in waste material, a high percentage of which stem from the family of so‐called “commodities”. Bearing this in mind, it is essential to develop a recycling system in order to avoid the environmental deterioration their presence causes and to reuse materials whose composition enables their recovery. The first problem this paper deals with is the separation of individual polymers before recycling in order to obtain regenerated products of high quality with consequently greater value.The work involves an attempt to use chemical additives as tracers in commonly occurring plastics such as PE, PVC, PP, etc. The tracers must be non‐toxic and must not alter the physical or transformation properties of the plastics. They should be identifiable by simple spectroscopic methods so as to enable physical separation of different polymers prior to rec

ISSN:0258-0322    

DOI:10.1002/masy.19920570111

出版商:Hüthig&Wepf Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractWhile most poly(vinyl chloride) (PVC) produced in the United States is used in the manufacture of durable building products, emphasis recently has been directed at recovery of PVC from post‐consumer disposable items such as bottles, rigid containers and rigid film. Manual sortation involving visual inspection for either the characteristic blow molding scar or code marking is at best only 90% accurate. Recent activity has focused on development of automatic sortation based on recognition of the chlorine atom which serves as a “fingerprint” for identifying PVC. Two separate technologies for sortation of such packaging are discussed in this paper ‐ the first involves X‐ray fluorescence, the second utilizes electromagnetic radiation a

ISSN:0258-0322    

DOI:10.1002/masy.19920570112

出版商:Hüthig&Wepf Verlag    

年代:1992

数据来源: WILEY