Nonplastic residue

Testing with a Gieseler plastometer (ASTM D-2639) gives a semiquantitative measurement of the plastic property, or apparent melting of coal when heated under prescribed conditions in the absence of air. The chemical nature of the constituents that account for a coal s plastic properties is not known. The material thought to be responsible for the plastic properties of coal has been removed from coal successfully by solvent extraction, leaving a nonplastic residue. Such residue has been rendered plastic by returning to it the extracts obtained by the solvent extraction. No definite relationship has been established between the amount of extract and the plastic properties of the coal. 

The material thought to be responsible for conferring the plastic properties on coal can be removed by solvent extraction to leave a nonplastic residue (Pierron and Rees, 1960). Plastic properties can be restored to the coal be recombining the solvents extracts with the insoluble residue. The fluid behavior or plasticity of coal in the temperature range 300 to 550°C (572 to 1022°F) is widely used to estimate coking characteristics and may be important for predicting coal properties with respect to coal conversion processes. 

The experimental and numerical investigation described here explore the thermal destruction behavior of different plastic and nonplastic mixmres in a laboratory-scale facility and its effect on carbon monoxide, particulates, dioxin, furan, and toxic metals emission. The results show that the composition of the waste has a significant infiuence on the emissions characteristics. The results also show that by using a suitable combination of various components in the waste, enhanced burning of waste occurs with reduced toxic emissions and solid residues. 

At the plastics processor, the baled HDPE containers are usually shredded, washed, and sent through either a float-sink tank or a hydrocyclone to separate heavy contaminants. Air classification may be done prior to washing. The clean materials are dried and then usually pelletized in an extruder equipped with a melt filter to remove residual nonplastic contaminants. If mixed colors are processed, the result from typical curbside or drop-off programs is a grayish-green color, which is most often combined with a black color concentrate to produce black products. 

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