Environmental Engineering Reference
In-Depth Information
a feedstock. As with many emerging industries, new incentives will be required to
stimulate market uptake and attract the necessary private investment required in
the development of new bio-based products and the large-scale deployment of
integrated biorefineries [36, 37]. For example, the US Federal Government set up
the BioPreferred programme in 2002 to increase the purchasing of bio-based
products [49].
One of the main drivers for the use of bio-based products (energy, chemicals
and materials) is their potential environmental benefits compared to petroleum-
derived products (e.g. carbon dioxide emission reduction, biodegradability). It is
therefore essential that we assess the environmental impact of all the energy and
chemical products manufactured by biorefineries (across their life cycle) to ensure
that they are truly sustainable and represent real (environmental and societal)
advantages compared to their petroleum-derived analogues [67]. In particular, the
impacts of direct and indirect land-use change and biomass production on regional
biodiversity need to be evaluated as part of this assessment [50]. Work is currently
underway through a number of initiatives to reach agreement at an international
level on sustainability principles, criteria and indicators [36].
1.5.4
Biorefinery Size
Biorefineries are emerging around the world in a variety of different forms and
sizes and encompass a combination of large-scale facilities (which can take full
advantage of the economies of scale, enjoying greater buying power when
acquiring feedstocks) and small-scale plants (which can keep transport costs to an
absolute minimum and take full advantage of available process integration tech-
nologies). Their optimal size, which will obviously depend upon the nature of the
feedstock(s) processed, the location of the plant, the technologies employed and
the demand for given products (not 'one size fits all'), will correspond to a balance
between the increasing cost of transporting pre-treated biomass and the decreas-
ing cost of processing as the size of the biorefinery increases [33, 36].
Many of these integrated biorefineries are expected to be located in rural or
densely forested areas in close proximity to the biomass (e.g. POET in US,
Processum in Sweden), while some are likely to emerge in large ports and refinery
complexes (e.g. Nestle Oil in Rotterdam, ENI in Venice), making the most of
existing infrastructures and easy access to key markets and customers.
1.6 Conclusions
Current industrial economies are largely dependent on oil, which provides the
basis of most of our energy and chemical feedstocks; in fact, over 90% (by weight)
of all organic chemicals are derived from petroleum [29]. However, crude oil
reserves are finite and world demand is growing. In the meantime, there is increas-
ing concern over the impact of these traditional manufacturing processes on the
