Waste processing plant for recovery of reusable materials separates waste into fractions according to weight and a sorted heavier fraction is preshredded and returned to the flow line

摘要

Waste is divided into two or more different fractions(36.1,36.2,36.3) according to size by a sorting unit(36). Subsequent size reduction equipment(42) shreds the fraction of larger waste(36.3) and a conveyer(48) returns this shredded waste to the main material flow passing through the sorting unit where it is again divided according to size and the process repeated. The heavy fraction(36.3) may pass through manual sorting units(38) for sorting into recyclable waste(46) which returns to the process and non-suitable waste(28.1,30.1) which is removed. A conveyer system(18,20) supplies waste to the plant and creates a uniform material flow. An extractor(26) following the conveyer system and preceding the sorting unit(36) selectively sorts waste which is too large for the plant. The sorting unit is preferably a sieve and in particular a flat screen. Further sorting units(58,60,62) sort the small waste according to size and/or type so that ferrous(52) and non-ferrous(54) metals, wood, paper, cardboard, films and other plastics can be recovered. Other small waste components with organic material and free of metals are recovered separately. Waste of small size(36.1), e.g. =60mm, is sorted according to weight(58) after metal extraction. Medium sized waste, e.g. 60-200mm, is separated into heavier and lighter fractions. The lighter fraction passes a sensor for detecting films, paper and card. A heavier fraction passes through further ferrous and non-ferrous metal extraction units. Lightweight waste containing paper and card and free of metals is passed through a cutting mill and other waste through a granulator. Conveyer belts(48), which can be driven in both directions, allow partial or repeated recycling of the sorted waste through the plant. Following all metal extraction from the medium sized waste the latter is divided according to weight and/or shape into two or three part fractions. PVC (Polyvinyl chloride) is sorted from the lighter or medium sized fractions and remaining waste passes to a granulator which produces a combustible material.