Plastic waste containers

British thermal unit Btu is the energy needed to raise the temperature of 1 lb of water 1°F (0.6°C) at sea level. As an example, one lb of solid waste usually contains 4500 to 5000 Btu. Plastic waste contains greater Btu than other materials of waste. 

This type of process is the preferred choice for treating plastic wastes containing a high proportion of components that may affect negatively the catalyst performance. The occurrence of a previous thermal step allows for the removal of many of these components previously to the catalytic treatment. 

Figure 10.17 DSC curves of plastic waste containing several polymers low density polyethylene (LDPE), high density polyethylene (HDPE), polypropylene (PP), Nylon-6 , Nylon-66 and poly-tetrafluoroethylene (PTFE). (Reproduced with kind permission of Springer Science and Business Media from M. Brown, Introduction to Thermal Analysis, Kluwer Academic Publishers, Dordrecht. 2001 Springer Science.)...

Similarly, the increasing efforts in recent years to recycle used plastics and plastics waste involve a number of analytical problems. Plastics waste containing a mixture of plastics can often be sorted using simple methods to identify the different plastics. It is stUl difficult, but possible, however, to automatically identify the different plastics and to sort them at the same... 

Experimental and theoretical studies are presented from a laboratory-scale thermal destruction facility on the destructive behavior of surrogate plastic and nonplastic solid wastes. The nonplastic waste was cellulosic while the plastic waste contained compounds such as polyethylene, polyvinyl chloride, polystyrene, polypropylene, nylon, rubber, and polyurethane or any of their desired mixtures. A series of combustion tests was performed with samples containing varying composition of plastic and nonplastic. Experimental results are presented on combustion parameters (CO, excess air, residence time) and toxic emissions (dioxin, furan, metals). 

PVC has a special position in the recycling of plastics [1]. As a result of the relatively weak bonding of chlorine to the polymer chain, the chlorine atom is split off at low temperatures of about 150 °C and hence complicates the material recycling of plastics wastes containing PVC. Corrosion, which could be initiated by the released chlorine or hydrochloric acid produced from it is less of a problem than the coal like polymer residue, which remains suspended in the machine or is distributed in the melt and further in the product. Many times it produces breakdown of the equipment and necessitates cleaning of the screw, barrel and dies. Therefore as a rule, PVC must be carefully removed from mixed plastic waste before most types of recycling - material or chemical. Because the significant difference between the density of PVC and that of other thermoplastics separation with one of the well known methods is possible. It is, however relatively expensive. 

Hydrolytic Treatment of Plastics Waste Containing Paper... 

Sample A source-separated plastics waste from households, collected in Gothenburg (collection test), Sweden, representing post-consumer mixed plastics waste containing paper. 

Figure 1. Influence of the hydrolysis temperature (melt temperatme in the ractor) on the mechanical properties of plastic waste containing 30% paper. Sample B, formic acid in gas phase, treatment time 3 hours. Values at room temperature (RT) refer to the unhydrohzed sample.

In conclusion, the method of hydrolysis offers an efficient and economical way of processing plastics waste, both post-consumer waste and industrial waste, contaminated with a cellulose component. The addition of cellulose gives a desired stiffness to the final product, as reported in earlier publications. Thus, the plastics waste containing a cellrdose component can be used in several applications, such as artificial wood. 

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