Chemistry Reference
In-Depth Information
Non-renewable
Energy
B/G 1-6: ancillary inputs to crop
farming
Aquatic Toxicity
B/G 7: crop farming
Human Toxicity
B/G 8-10: transport (grain from
B/G to F/G)
Eutrophication
Photochemical
Oxidant Creation
B/G 11-17: ancillary inputs to F/G
Ozone Depletion
B/G 18: treatment of effluents
from F/G
Global Warming
(100 yr)
F/G: sites 1-4 + transport steps
Acidification
0%
20%
40%
60%
80%
100%
Fig. 5.14
Life-cycle impacts of the Scotch whisky system (B/G
=
background; F/G
=
foreground).
current operations in Fig. 5.15. To preserve confi-
dentiality, the impacts of the optimised system are
expressed relative to the current operations. It is
obvious that almost all impacts from the optimised
system are lower than those from the current oper-
ations. For example, global warming and energy use
are reduced by 45%. The largest improvements are
noticed for human and aquatic toxicity, with reduc-
tions of almost 100% and 80%, respectively. The
main reason for these reductions is the elimination
of pesticides in organic farming.
On the other hand, there is a significant increase
in two other impacts, i.e. eutrophication and acidifi-
cation. A 250% increase in eutrophication is due
to the application of organic fertiliser (manure) and
associated emissions of nitrates to water and lower
productivity per area of land in organic farming [52].
A similar increase in acidification (210%) is due to
ammonia emissions from the manure and additional
farm machinery required per tonne of grain in
organic farming. Organic farming also carries a
financial penalty because of the higher price of
organic grain, which at present is about twice that
of intensive-farming grain. The question facing the
decision-makers then is whether a nearly complete
elimination of human and aquatic toxicity is more
important than a twofold increase in eutrophication,
acidification and costs. This is equivalent to the val-
uation step in LCA, which involves elicitation of the
• Substitution of intensively farmed grain for organ-
ically grown cereal (wheat, maize and barley)
For the foreground system:
• The use of artificial enzymes for grain starch li-
quefaction and saccharification instead of malt
addition, to reduce costs and remove the require-
ment for barley production
• Recycling of part of the distillation effluent to the
cooking process to reduce energy, water usage and
amount of effluent for treatment
• Very high gravity brewing instead of conventional
brewing to reduce energy and water usage and
amount of effluent for treatment
• Anaerobic digestion of spent wash and utilisation
of generated biogas as fuel, displacing the animal
feed plants
• Optimisation of maturation conditions by optimis-
ing fill strength and cask size to prevent product
evaporation losses.
The OLCAP methodology [75] has been used to
integrate these improvement options into the LCA
optimisation framework as defined by Eqns. (5.4).
The results of optimisation are compared with the
