Environmental Biotechnology - Theory and Application

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Chapter 8 Biotechnology and Waste


As mentioned in the first chapter, waste represents one of the three key inter-
vention points for the potential use of environmental biotechnology. Moreover,
in many ways this particular area of application epitomises much of the whole
field, since the management of waste is fundamentally unglamorous, typically
funded on a distinctly limited budget and has traditionally been viewed as a nec-
essary inconvenience. However, as the price of customary disposal or treatment
options has risen, and ever more stringent legislation been imposed, alternative
technologies have become increasingly attractive in the light of their greater rel-
ative cost-effectiveness. Nowhere has this shift of emphasis been more apparent
than in the sphere of biological waste treatment.
With all of environmental biotechnology it is a self-evident truism that what-
ever is to be treated must be susceptible to biological action and hence the word
‘biowaste’ has been coined to distinguish the generic forms of organic-origin
refuse which meet this criterion, from waste in the wider sense, which does
not. This approach also removes much of the confusion which has, historically,
dogged the issue, since the material has been variously labelledputrescible, green,
yard, foodor even justorganicwaste, at certain times and by differing authors,
over the years. By accepting the single termbiowasteto cover all such refuse,
the difficulties produced by regionally, or nationally, accepted criteria for waste
categorisation are largely obviated and the material can be viewed purely in terms
of its ease of biodegradability. Hence a more process-based perspective emerges,
which is often of considerably greater relevance to the practical concerns of actu-
ally utilising biotechnology than a straightforward consideration of the particular
origins of the waste itself.


TheNatureofBiowaste


Biowaste arises from a number of human activities, including agriculture, hor-
ticulture and industry, broadly falling into one of the following three major
categories: faeces/manures, raw plant matter or process waste. This fits neatly
into the process-orientated approach mentioned above, since the general char-
acteristics of each are such that biological breakdown proceeds in essentially
the same manner within the group and, thus, the ease of their decomposition
is closely similar. Although, at least chemically speaking, biowaste can be seen

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