Shredding waste

In 1985, the Emanuel Tire Company in Baltimore processed more than 3 x 10 tires into chips, which are mostly sold to pulp and paper mills as a supplemental fuel the remainder is sold to reclaiming facHities or landfiUed. Only 20% of passenger tires are suitable for recapping. Nonrecappable tires are shredded into 5-cm chips. The Emanuel Tire operation is capable of reducing the 5-cm chips to smaller sizes. Shredded waste tire chips can be granulated into very fine wire and fabric-free mbber particles. 

Size of material shredded Wastes to he digested should he shredded to a size that will uot interfere with the efficient fuuctioniug of piimpiug aud mixiug operations. 

Gasification of the shredded waste material in a revolving fluidized bed, operated at 500-600° C, which separates combustible part from inert and metallic ones. Combustion of syngas and char in a cyclone combustor... 

High-temperature pyrolysis (800°C) of the shredded waste conveyed by a screw feeder. Fixed-bed gasification of the char residue. Combustion of gas from pyrolysis and gasification units at 1250°C in a high temperature furnace... 

A low cost system for smaller communities is shown in Figure 1. It consists of a shredder to reduce the size of waste paper, a densification system to convert the shredded waste paper to a dense fuel "cube, the gasification reactor, a gas cleanup system, and an engine-generator to convert the gas to electrical power. 

Bosscher, P.J. Edil, T.B. Eldin, N.N. Construction and Performance of a Shredded Waste Tire Test Embankment, 71st Annual Meeting Transportation Research Board Washington, DC, Jan, 1992. 

Bosscher PJ, Tuncer BE, Nefl NE (1992) Construction and performance of a shredded waste tire test embankment. Presented at the 71st Annual Meeting of the Transportation Research Board, Washington, DC, p 312... 

Minnesota Pollution Control Agency (1990) Waste tires in sub-grade road beds environmental study of the use of shredded waste tires for roadway sub-grade support Waste... 

EdU TB, Bosscher PJ (1992) Development of engineering criteria for shredded waste tires in highway applications. Final report to the Wisconsin Dept of Transportation... 

The F/L wet-cell of Lee and Jones-Lee (1993) requires that shredded waste be emplaced in order to improve fluid hydraulics, but until practices such as this... 

The fluidized bed incinerators use a distinctly different combustion technique. The incinerator vessel contains an inert bed of particles that are kept in suspension by fluidizing air flowing through the bed at a rate that is just rapid enough to sustain that condition. The shredded waste ignites instantly upon introduction into the fluidized bed incinerator. The combustion of both the solid and gaseous fractions of the waste is accomplished in one chamber and the fly ash resulting from the process leaves the chamber with the off-gas. 

Shredded tyres can be used in the construction of landfill sites as a replacement for other construction materials. The areas that they are used in include lightweight backfill in gas-venting systems, leachate collection systems and operational liners. Shredded waste tyres can also be used to cap, close or daily cover landfill sites [75]. Their use as a backfill material and cover material can be more cost-effective than the use of other fill materials, as they can be shredded on site rather than being transported in for that particular purpose. 

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