Conclusions

The main conclusion of this paper is a real and practical possibility of recycling of thermoplastic materials using an integrated management scheme in which plastic wastes are subjected to sequential recycling from initial high performance and high cost applications to subsequently lower performance and lower cost applications. Thus, based on the technical conclusions regarding recyclability of plastic wastes, it is necessary to create laws regarding generation, collection, and location of...

Quality Assurance To En Pp

The EN 29,000 pp standards provide a selection of quality assurance elements and a guideline for establishing quality assurance systems.2 The selection of an optimum quality assurance system is governed by many diverse factors such as the application-specific objectives, the specific products, special processes, and the size of the plant. Corresponding models are given in EN 29,001 to 29,003. However, the key elements are always the same, irrespective of the quality assurance system selected....

Air flotation

Specially designed machines combining the effects of vibration and air flotation ensure separation of flakes with different specific weight. Such machines are very useful for removal of parts of labels which were freed by grounding. The purpose of this operation is the removal of a part - important with regard to volume and weight in the dry phase. Process allows to avoid problems of dissolution in water and relevant contamination. An extremely interesting and certainly unique application of...

Blends containing calcium carbonate

Calcium carbonate is widely used as an inexpensive filler for many polymers. For this reason (a significant reduction of the cost of these recycled materials), PE MPW blends with different amounts (10 and 20 ) were prepared and characterized. The mechanical properties of the blends with 50 of MPW are reported in Figures 8-11 as a function of the calcium carbonate content. The blends with 10 and 25 of MPW and with the same amounts of CaCO3 were also prepared and tested. The results are reported...

Blends containing LDPE

On the basis ofthe above results, blends made from LDPE with larger amounts of MPW were prepared. It is worth noticing that all blends previously characterized were composed of polyethylene matrix (PE > 50 ) with dispersed PET and PVC particles. Blends with larger amounts of MPW show a PE content lower than 50 . The mechanical properties of LDPE MPW blends with and without calcium carbonate are reported in Figures 12-15 as a function of the polyethylene content. The total amount...

Coextruded films

In Table 6, the mechanical properties of two coextruded films are reported for samples cut out in the draw direction and in the transverse direction. The tensile properties in the draw direction of the V Ny coextruded film are significantly larger than those of the R2 Ny film, whereas in the transverse direction they are similar. This unusual behavior is probably due to the different rheologi-cal properties of two PE samples. Indeed, the film blowing operation has been carried out using the...

Concepts For Car Interiors

New developments in polyolefin-based materials have created a family of polypropylene products with a wide range of physical properties, including the ability to be easily recycled. When utilized by automotive and product designers as a part of a design for disassembly strategy, these compatible materials will y-5eld large sub-assemblies that can be reclaimed with a minimum of handling. - In each project, the design incorporates readily identifiable hard point connections between the...

E

Elastic modulus 30, 35, 36, 51, 89, 95, 125 electrostatic separation 103 elongation 30, 35, 36, 50, 68, 70, 88, 89, 90, 93, 94, 96, 119, 121, 125, 126 ESCA 162 esterification 4 EVA 63, 68 extrusion fiber 1, 2, 114 fillers 55, 76, 93, 94, 95, 96, 97, 125, 153 film 1, 2, 3, 10, 12, 27, 28, 30, 36, 37, 60, 62 filmbase 3 flexural modulus 53, 54 floor coverings 134, 135, 136 flotation 42, 62, 104 flow index 148, 157 foam sheets 132 fogging 133 fracture 78 fuel tanks 146 functionalization 28 glass...

Experimental

The characteristics of materials used as a matrix in this work are reported in Table 1. The recycled polyethylene (RPE) was obtained from films for agricultural use and is, therefore, mostly composed of a low density polyethylene. The average composition of the mixed plastics waste was PEs 33 (mainly HDPE from blow molded detergent bottles) PVC 39 (plain mineral water bottles) PET 28 (soft drink and carbonated mineral water bottles). Such composition is representative of the average composition...

Floor covering

The structure proposed does include a lower high density TPO based sheet, an intermediate polypropylene felt layer, and a polypropylene fiber carpet (loop pile or cut pile ) on the top. A sketch of this component is shown in Figure 7. The recovery possibilities of the scraps from the sandwich production (about 20 ) and material coming from the whole structure are the following after passing through a mechanical mill, the material can be calendered and then processed by injection molding as well...

Ground Rubber Tire And Recycled Plastics

In order for GRT composites to find high volume applications they have to be a lower cost replacement for virgin, commodity polymers. To achieve this, each aspect of the composite fabrication process, from tire collection and grinding to compounding and final product manufacture, has to be optimized on a cost performance basis. One very attractive approach to minimizing overall composite costs is to utilize recycled polymers as the matrix phase in place of virgin materials. There are also a...

Identification of polymers present in the film plastic wastes and the rheological behavior of the HD

Hdpe Rheology

In Figures 2 and 3 IR plots and DSC curves of HDPE, LDPE, wastes, and some blends are reported. Two remarks can be made concerning these data the film plastic wastes from Madrid constituted, in 1985, mainly of HDPE and LDPE, having 20 70 HDPE LDPE ratio deter-the peak Figure 3. DSC thermograms of HDPE and LDPE and their blends obtained from waste materials. Figure 3. DSC thermograms of HDPE and LDPE and their blends obtained from waste materials. in HDPE LDPE blends.21 The rheological study of...

Introduction

Discarded tires represent a significant component of the overall plastics recycling challenge. They are an easily segregated, large volume part of the waste stream and present their own, somewhat unique, waste utilization problems. The whole issue is complicated by many alternative proposals, varying government legislation and preferences, incomplete technical information, and economic uncertainties.1 A number of reviews have already discussed this overall disposal problem and examined many of...

Outlook

Materials used today for the production of consumer goods and durables will appear on the recycling market tomorrow, provided they are routed for reuse. Polymers constitute a major source material for the production of commodities. Currently, concepts are being developed and first steps taken to facilitate and improve the separation of polymers from the product after its useful life has elapsed. This can be achieved by designing products for maximum ease ofdisas-sembly and identifying them...

Photodegradation

Special photodegradable polymers30 were synthesized for the purpose of having them destroyed after use (e.g., in a landfill). Another approach was the incorporation of suitable groups (e.g., carbonyl) in the polymer backbone in order to make polymer photodegradable by sunlight or UV (see Figure 6). A problem arises due to the fact that light exposure conditions on a landfill cannot be regulated. The main difficulty, however, seems to be practically insurmountable it is

Present Recovery Practice

A discarded vehicle may first be stripped of resaleable parts by a salvager (wrecker) or dismantler, or it may go directly to a scrap processor, who may or may not strip such parts before processing the hulk. Until some twenty years ago processing usually took the form ofcompression into a cuboid or rectangular bale, known in the USA as a No. 2 bundle, and in the United Kingdom as a No. 5 bale. Sometimes, where air pollution regulations permitted, the hulk was incinerated to remove non-metallic...

Procedures and Utilities

The study of the rheological behavior of wastes and HDPE LDPE system was carried out using a torque-rheometer.16 Physical properties of polymers and wastes used in this work Physical properties of polymers and wastes used in this work Blends, having 15 85, 50 50, and 85 15 of HDPE LDPE ratio, were prepared according to an experimental design method by Box-Wilson. The experimental design consists of thirteen experimental combinations distributed as follows four combinations corresponding to the...

Recyclable Plastics Components

An alternative approach to the recovery of automotive plastics is to use them as large, easily removable components which offer potential for reclamation as well-characterised individual polymers. Some particularly complex components, such as vehicle front- and rear-end systems, exhibit special suitability for manufacture in plastics instead of metals, because of their ease of production and assembly. Plastic fuel tanks are now in common use, and an investigation has been made of some...

Recycle Installations

A special importance is generally devoted to the techniques of electronic selection of homogeneous fractions, while disregarding the phase of regeneration of selected plastic flakes. This minor interest would be justified if bottles were manufactured following criteria of perfect recyclability. However, such criteria are not yet universally accepted and complied with therefore the recycling plant designer must give an accurate response to the problems posed by various elements which normally...

Recycling of urban plastic wastes

The initial step, i.e., source identification, was previously discussed.1 Once the source is identified, the first question regards the composition of the source ifplastics are mixed with other materials (glass, paper, organic), a separation is needed if plastics are dirty (clays or similar contaminants), wastes must be cleaned if the plastic waste consists of a polymer blend, the situation is much more complex. The problem was studied by comparison between the polymer blend of the plastic...

References

Henstock, Design for Recyclability, London, The Institute of Metals, pp. 3-6 (1988). 2. K. C. Dean and J. W. Sterner, Dismantling a Typical Junk Automobile to Produce Quality Scrap, United States Bureau of Mines, RI 7350, Washington, (1969). 3. M. E. Henstock, Conservation and Recycling, 2 (1), 69 (1988). 4. R. Franklin, Recycling Cars, Materials Reclamation Weekly, 8 December, 21 (1990). 5. K. D. Marshall, The Economics of Automotive Weight Reduction, Soc. of Automot. Engrs, Paper No....

Results

The post-consumer plastics waste, sample A, collected from households in Gothenburg contained two different paper components milk packages (laminated board) and newsprint. Laminated board is normally very difficult both to grind and to reprocess. Sample A contained 46 paper and was found impossible to injection-mould without hydrolysis. The stiffness of sample A subjected to hydrolysis is very high (E-modulus 3.9 GPa, strength at break 15 MPa, elongation 1.2 , impact strength 9 kJ m2 Charpy...

Changes In The Materials Used In Vehicles

Changes in vehicle materials are made for a variety of reasons, including cost, absolute performance, lightness, (to improve fuel economy), and longevity. The magnitude of fuel savings over an estimated 174,000 km vehicle road life has been computed as 15-25 l kg of weight saved.5'6 Though improved engineering design may achieve weight reductions, a point is reached where further improvements may be made only through the use of light materials. Considerable effort has therefore been devoted to...

Summary And Conclusions

The monetary value of recoverable materials in road vehicles has fallen as plastics have replaced steel. Increases have occurred in the cost ofthe labour for scrapyard dismantling and in the amount of unsaleable residue and, therefore, in the associated disposal costs. Improvements in scrapyard economics may possibly be achieved by the prior removal from vehicles of large polymeric components and their recycling as well-characterised plastics fractions. Some trials with material recovered from...

Synthetic leather

The TPO synthetic leather was produced from a resin studied to have a good processability both by extrusion, the traditionally utilized for polyolefins manufacturing, and calendering, the most employed technology in producing PVC and PVC ABS synthetic leathers.1 The embossing, as well as the coupling with a large variety of different layers (e.g. films, woven and non-woven structures, foams sheets) can be easily obtained in line, using traditional technologies. The thermoformability ofthe TPO...

The economical approach

Based on preliminary results, the design of a plant for treatment of the film plastic wastes was completed in 1985. The facilities were designed to produce pellets from the film plastic wastes ready to run a production with substitution of the required percentage of LDPE virgin resin. The mass balance and implementation of the plant design can be seen in Figures 19 and 20, respectively. The preliminary economic study was carried out according to Machinery and Engines Charge.30 Satisfactory...

Tire Grinding

In order to be used as a filler in polymer composites, tires are first ground into a fine powder on the order of 100-400 m. This is accomplished typically through either cryogenic or ambient grinding. General reviews of the size-reduction process have been published. - A typical process generally involves tire splitters to cut the tire initially, followed by a two-roll grooved-rubber mill or hammer mill. The bead wire is removed by hand or with magnets and fiber is removed at intermediate...

Washing equipment

Residues are normally washed out of material flakes by means of equipment whose construction details, guaranteeing of their performance, are kept secret by manufacturers as much as possible. autoclaves for flakes-detergents contact scraping machines (mechanical friction) centrifugal machines, normally used for water separation. The installation of the above machinery according to a specific sequence is part of a know-how of various manufacturers. In conclusion, in view of complex problems posed...

Basic Technology

Injection molding technology involves the injection of molten plastic into one or several cavities via a hot-runner system (melt-channel distribution system) and rapid cooling of a preform to a low temperature. At this point the freshly manufactured article can be ejected from the cavity. In multilayer technology, more than one plastic resin is injected into the cavity. The different resins are molten in separate injection units, conveyed in separate hot-runner channels, under pressure and high...

Experimental Materials

The virgin polymers used in this study are described in Table 1 as well as the composition of their mixtures. Note that LDPE is a blend of two LDPE's having different molecular weights and PS is a high impact PS, containing some elastomers selected to improve similarities with real wastes components. Some physical characteristics of homopolymers and compositions of the studied mixtures Some physical characteristics of homopolymers and compositions of the studied mixtures Blends of the plastic...

Plastics From Industrial Sectors

As mentioned before, plastic waste from the industrial sectors concerns the medium long life articles. The main problem of these sectors, and in particular the car industry, is the large variety of materials employed to build a single component or system, for example a dashboard. This takes place because of the sophisticated and complex mission that the system must perform. Plastics have played a fundamental role, thanks to their special capacity for interpreting the design function synthesis,...

Foam sheets

The technology used for the production of TPO based foam sheets cannot be fully disclosed here. The research guidelines were principally oriented to overcome some limitations in physical foaming of polypropylene, related to intrinsic rheology and kinetics of crystallization.2 These materials present a loss of stiffness quite abrupt near the melting point, due to the melting of a crystalline UV resistance ofHIFax CA12A (UV exposure in Xenotest 1200 according to ISO-4892) UV resistance ofHIFax...

Hydrolysis

All samples were ground in a mill (Rapid GK 20, high-speed rotation knife mill, normally fitted with a 25 mm screen). When subjecting the waste material to the hydrolytic treatment, three methods can be employed hydrolysis after impregnation with the acid solution and drying hydrolysis with acid in the gas-phase. All these methods were discussed previously.3 Using the first method, the waste material was suspended in the acid solution (solid liquid ratio 1 9) and the mixture boiled for about...

The Effects Of Materials Substitution On Vehicle Recycling

The energy crisis of 1973 changed the purchasing patterns for cars. The real price of oil has fallen significantly since that time, and large cars are again in demand, especially in the United States. However, some of the move towards smaller and lighter vehicles is undoubtedly permanent, and the future shape of the vehicle recycling industry may be analysed in terms of possible changes in size and weight of cars, and also in their composition and mode of manufacture. A detailed analysis by...

Resource Recycling

Plastic Recycling Production Flow

Originally, industrial production relied on a linear material flow. Raw materials were mined and upgraded, premixes produced for the manufacture of components and equipment which were then utilized and eventually dumped into landfills after their useful life had elapsed. As the proportion of synthetic products in the total production volume increased, landfilling became ever more of a problem. The consequences of this disposal practice became unforeseeable. The price of landfilling rose...

Dashboard

Figure 6 shows a sketch of the dashboard designed for recycling and obtained with a process based on the previously described assembling technique. The system has three basic components, that, in the past were made of different materials in a new design this system has been molded from TPO based polymers to provide rigidity, comfort, safety, and aesthetics. Some prototypes have been recycled following the traditional procedures for the scrap recovery of thermoplastic materials. The mechanical...

Rheology

The rheological behavior of polyolefin blends has been widely studied by many authors. It was found that the shear viscosity exhibits maxima and minima when plotted as a function of composition. In general, the viscosity vs. shear stress trends for the binary blends, which present negative (PS LDPE, PS PP, 16 21 22 PS HDPE) and positive (PP HDPE) deviations, cannot be super-imposed into a master curve by a simple horizontal shift. In other words, the shape of dependence changes with...

Used Battery Recycling

Recycle Flow Diagram Batteries

Lead-acid batteries from automotive applications normally have a shorter service life than the car itself. After their service life has elapsed, they are no longer suitable for use. Because of their high lead content, lead-acid batteries have always been eagerly snapped up by secondary lead smelters. Via the car dealer and garage network, lead-acid batteries are collected in large quantities and then transported to secondary lead smelters. The logistics system is geared to lead recycling. The...

Ground Rubber Tire Composite Behavior

Although the use of ground rubber tire GRT as a filler in polymer blends is a potentially attractive approach, it is fraught with a number of difficulties. Generally, when the large GRT particles are added to either thermoplastic or thermoset matrices there is a large drop in mechanical properties, even at relatively low filler loadings.6'7 Given that the approach here is to use the GRT as a low cost additive, and that there are a number of other materials competing in this regard, overcoming...

Recoverable Materials In The Motor Vehicle

Discarded vehicles yield ferrous metals, aluminium, copper, lead, and zinc. However, as currently processed by shredding, they also generate a valueless fraction, containing the non-metallic detritus of seats, carpets, tyres, and other components. The historical position of steel in the automotive scrap industry emerges from data for the composite car described in the pioneering work of Dean and Sterner. The recovered steel, even when contaminated with the residual copper in the car, would have...

Results And Discussion Processing

When mixed plastics waste is processed, one ofthe main problems is to find the best compromise between homogenization and degradation. In the waste material, there are polymers with different melting points and different thermal stability. Especially, PVC and PET are very difficult to process together, because the melting point of PET is over 250oC, and at this temperature PVC is easily decomposed forming HCl and chary residues. Therefore, the optimal processing Figure 1. The modulus and impact...

Mechanical behavior of Hdpeldpe blends

Mechanical Behaviour Plastics

The mechanical properties of blends of virgin HDPE and LDPE and plastic wastes are below those expected on the basis of an additive rule.22-29 In Figure 5 Figure 5. Polar representation of mechanical behavior of HDPE LDPE system containing either virgin polymers or composition from urban wastes. Figure 5. Polar representation of mechanical behavior of HDPE LDPE system containing either virgin polymers or composition from urban wastes. a polar representation was plotted showing the mechanical...

Quality of the raw materials

Virgin PET had an intrinsic viscosity of 0.78 dl g and was crystallized and solid state-polycondensed upgraded by the chemical manufacturer. PET reground flakes came from an unknown PET source. The flakes consisted of 100 PET before the reground bottle flakes went through a separation and clean-up process. The flakes were not regranulated since this step involves separate machinery and would add to the cost of the reground polymer material. The intrinsic viscosity was 0.03 to 0.05 dl g lower...

Mechanical Properties

The mechanical properties of all the investigated materials are reported in Figures 2-5 as a function of the mixed plastics waste concentration. The experimental results are reported in dimensionless form, i.e., the value relative to each blend is divided by the corresponding value of the unblended matrix. These latter values are reported in Table 2 for three matrices. As expected, all the mechanical properties, except for the elastic modulus, decay on increasing the MPW content. The extent of...

Microstructural aspects of Hdpeldpe blends

Microstructure Pehd

Figures 9 to 10 show micrographs of the microtomed sections from injection molded bars. The different microstructure of HDPE LDPE blends, having different compositions, are shown Figure 9 . In fact, these thin sections taken in the parallel flow direction inside the cavity of a mold and near the gate, show differences in Figure 13. Micrographs of 85 15 left and 15 85 right HDPE LDPE ratio with 1 LMWPE. Figure 13. Micrographs of 85 15 left and 15 85 right HDPE LDPE ratio with 1 LMWPE. Figure 14....

Drying of PET resin and PET flakes Figure

Crystallizers For Pet Flakes

The drying of a virgin PET resin and reground PET flakes at temperature levels of 160-180oC to below 0.005 moisture content is essential for the production of amorphous multilayer polyester bottles. Polyester is an effective desiccant. The water absorption depends on a relative humidity, residence time, temperature, and dimension of the flakes. When flakes containing moisture are heated up to the melting temperature, hydrolytic degradation occurs lowering a viscosity ofthe melt that results in...

Direct Reuse

Flow Sheet Recycling Pet

Over 50 of the PET film produced in the world is used as a photographic filmbase. The manufacturers of these materials, mainly Agfa-Gevaert, Eastman Kodak, du Pont de Nemours, Fuji, Minnesota Mining amp Manufacturing, and Konishiroku have long been interested in PET film recovery. An important motivation for the efforts made by these companies is the fact that photographic films are usually coated with one or more layers containing some amount of rather expensive silver derivatives, which have...

Anon 784248 1957

Boettcher, ACS Polymer Preprints, 32 2 , 114 1991 . 2. W. De Winter, Die Makromol. Chem., Macromolecular Symposia No. 57, 253 1992 . 3. Anon., Plastics Bulletin, 174, 6 Jan-1992 . 4. N. Basta et al., Chem. Eng., 97, 37 Nov-1990 . 5. Brit. Pat. 1.476.539 1977 to Barber-Colman Co. 6. Anon., Manufacturing Chemist, 66, Mar-1987 . 7. L. Hellemans, R. De Saedeleer, and J. Verheijen, US Pat. 4,008,048 1977 to Agfa-Gevaert. L. Jeurissen and F. De Smedt, Brit. Pat. 1,486,409 1977 to...

Disposal Of Residuals

An important financial element in recycling is residue disposal, whose costs are part of the overall economics of the recovery operation. Four general methods have been advanced for commercial utilization of the light fraction landfill, polymer-enriched fractions, structural materials, and fuels. It is unlikely that any revenue could be generated by landfill, since the non-metallic residue is voluminous, compressible, and lacks the properties desirable in hard-core. Current technology cannot...

HDPEheavy fraction blend

The HDPE heavy fraction blend, 75 25 was examined to evaluate a possibility of reusing of a heavy fraction as a filler of HDPE to obtain extrudates with appropriate rigidity. As indicated before, the heavy fraction was first ground to particles of about 100 m and then blended with HDPE pellets in a double-screw extruder at 180oC. At this temperature, all the components PVC, PET, nylons, crosslinked polymers, etc. are still solid in the molten HDPE. Morphological observation by SEM shows that...

Michael E Henstock and Klaus Seidl

The University of Nottingham, Nottingham NG7 2RD, England BMW, Section EG-554, M nchen, Germany In market economies recovery operations are judged on financial criteria. Thus, whether or not a discarded waste is exploited for the materials it contains depends, among other things, on the technical ease of recovery of a saleable secondary product. Since industry must also consider the environmentally-sound disposal of its residuals the ease of residuals disposal is financially important.1

Tpo Based Materials

Thermoplastic Elastomers TPE are classes of heterophasic polymers, characterized by thermo-reversible interaction among the polymeric chains. The new polymeric materials that are considered to produce easy recyclable automotive systems, can be defined as a sort of a new generation of Olefinic Thermoplastic Elastomers TPO , belonging to a broad family of polyolefinic alloys that can now be produced directly during the polymerization phase. These completely new materials, resulting from advanced...

Microseparation

Microseparation is a method by which a suspension medium is used to separate plastics with density higher or lower than the suspension medium. For example, water can be used as medium to separate PE from PVC or PET. In this case special tanks are used in which various types of plastic flakes are mixed with water and then given a sufficient time to position themselves in the most suitable way according to their density. Materials are subsequently extracted separately from the top or bottom. This...

Reuse After Modification

Pet Film Recycling Flow Chart

Similar to the method described under direct re-use, in which PET-flakes are added during the esterification process, PET-polymer is broken down into low-molecular, low-viscous fractions. Such method could already be viewed as a method of re-use after modification. Because the intermediate products are not separated at any moment of the process, the degree of purity of PET-scrap must be high. For PET-wastes having a higher degree of contamination, other technological processes are applied,...

Macroseparation

Container Trailer Diagram

Separation of plastic fractions when waste materials are still in initial form continues to appear the most conveniently applicable system, considering the increasing possibilities of automation it offers. It is of little interest as long as separation is manual, but it becomes worth discussing when conducted by an automatic separation process which includes various systems employing detectors currently available in the market. The first detector was developed by Tecoplast in Casumaro,...

Preliminary Results Comparison of virgin and recycled HDPE

The plastic fuel tanks investigated are produced from Lupolen 4261A, supplied by BASF AG, Ludwigshafen. In Stage 1 of the trials the virgin HDPE was formed into injection-moulded test pieces using an Engel CC 80 injection moulding machine, and tested in a variety of mechanical tests. The tested samples were then successively reground and remoulded. The following mechanical properties were assessed, and the change in each property reported after 15 cycles Comparison of fluorinated and...