The fundamental problem that faces the management of virtually all solid wastes is that
they comprise complex mixtures and are usually subjected to indifferent storage conditions
resulting in deterioration before collection and subsequent treatment.
The various strategies available for solid waste management must be considered as a
hierarchy of opportunities with waste reduction at source as the best option. Intuitively,
recycling would seem to be the second best option, but effective recycling and, for that
G. Hamer / Biotechnology Advances 22 (2003) 71–79 73
matter, effective modification (reprocessing) can only occur after complex wastes have
been separated (segregated) into their various fractions. Amongst the components of
municipal solid waste that are particularly suited to recycle are glass bottles and jars,
aluminum beverage cans, paper and cardboard, while hard plastics can frequently be
reprocessed into lower-grade material. Only then should the question of treatment be
considered and, as a last resort, disposal. Although zero waste (total elimination) initiatives
are frequently discussed, they have yet to become technological realities as far as the
majority of products are concerned.
The major feature of any solid waste that makes it suitable for treatment is that it is
either biodegradable or combustible, thereby dictating that such waste fractions must be
organic in nature