Waste melt processing

The volume of hulls generated is nominally 62 m /1 of fuel, which is about 10 times the actual volume of metal. Whereas they are not yet in commercial use, both compaction and melting processes are being developed to improve waste handling economics (41). 

Naskar, A.K., Bhowmick, A.K., and De, S.K., Melt-processable rubber Chlorinated waste tire rubber-filled polyvinyl chloride, J. Appl. Polym. Sci., 84, 622, 2002. 

CSMP [Cupola surface melting process] A process for vitrifying residues from the incineration of municipal wastes. Offered by ML Entsoigungs und Eneigieanlagen. 

Microwave solidification is an ex situ mixed-waste treatment process. The process is applicable for homogeneous, wet or dry, inorganic solids. The process dries the waste, mixes it with a matrix modifier, transfers it to a processing container, and subjects the mixture to microwave energy to melt the materials. The processed waste form then cools and solidifies to form crystalline mineral analogs. 

As illustrated in detail by Wolff, contaminants in Antarctic snow and ice have their ultimate destination in sea because of the melting process (51). The presence, origin (either local or from other continents) and fate of heavy metals, HNO3, H2SO4 and other substances from fuel combustion and waste burning were reviewed by this author. 

Stricter regulations are increasing the environmental compliance costs. This includes the costs to clean up contaminated air and water resulting from the melting process, as well as the costs to dispose of any waste products, which is particularly important for hazardous wastes. 

Waste of polyesters and polyamides may have suffered from the hydrolytic depolymerization. Thus, it may be necessary to increase the molecular weight by solid-state polycondensation under high vacuum, or by reactive coupling using such di-functional agents as di-glycidyls. Prior to melt processing, the resins should be dried to less than 0.01 wt% of moisture, re-stabilized and (if compounded with immiscible polymers) compati-bilized. 

The above data show that relatively good results can be obtained by this method as compared with melt processing of waste. 

Zhang Q, Dor L, Fenigshtein D, Yang W, Blasiak W. Gasification of municipal solid waste in the Plasma Gasification Melting process. Appl Energy 2012 90 (1) 106-112. 

Zhang Q, Wu Y, Dor L, Yang W, Blasiak W. A thermodynamic analysis of solid waste gasification in the plasma gasification melting process. Appl Energy 2013 112 405-413. 

In 1996, Austrian researchers developed a thermoplastic in which waste wood chips, com, and cellulose-derived resins were combined to produce a biodegradable and melt-processable wood. ... 

Polymers from carpet waste produced by melt processing may be used to make products in a molding process, either alone or blended with virgin polymers. The recycled polymers may also be used as matrices in glass fiber reinforced composites. For such applications, the properties of the composites are dominated by the reinforcement (glass fibers), and therefore even recycled polymers without compatibilization could provide the composites with satisfactory mechanical properties. ... 

The behaviour of FRs during recycling, either by melt processing or by incineration, has been the subject of some controversy, with most of the argument centring on brominated retardants, which are particularly suitable for moulded housings of electrical and electronics equipment. The European Commission, in its draft directive for recycling. Waste Electrical and Electronic Equipment (WEEE), proposed that such components should be removed from equipment and treated separately from the rest of the waste stream, which could amount to a ban. 

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