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tion methods which depend on the relevant impacts of interest and the chosen
assessment method. Finally, the results are analyzed to aid in the relevant decisionmaking process.
Furthermore, ReCiPe methodology (uses hierarchies, to include long-term
effects) has been chosen to include midpoint indicators, including freshwater
ecotoxicity, freshwater eutrophication, marine ecotoxicity, marine eutrophication,
and water depletion, although these indicators are obviously only related to the
assessments relevant to water-based ecosystems.
7.4 Discussion and Results
7.4.1 Energy and Renewable Input Resources
Environmental impacts associated with energy consumption and water use are
among the most important issues for the mining industry (Pimentel et al. 2016).
Consumption of energy, nonrenewable and renewable resources (water) is clearly
emphasized for each stage listed above, with the challenge being to improve the
efficiency of both mining systems. It should also be pointed out that greater
environmental impacts are expected from the stages with the highest consumption
of nonrenewable and renewable resources. As such it is clear that the global
production-consumption cycles of minerals, water, and energy are inextricably
connected.
7.4.1.1 Energy Consumption in Mining Activity
Northey et al. (2013) suggest characterizing energy consumption by type (electrical,
diesel input for machines, gas) and electricity source (produced on-site or off-site)
to find specific opportunities for improving resource consumption and sustainability
reporting (Northey et al. 2013).
Values for direct and indirect energy consumption provide an approximation of
the electricity, gas, and energy acquired by mines or generated in situ. Figure 7.3
shows energy consumption, energy losses (38.93% of the total energy input), and
total useful energy (61.07% of the total energy input) for open-pit mining systems.
Additionally, 63.56% of the total energy consumed comes from electricity, 35.91%
from diesel, and 0.53% from gas. Highest electricity, gas, and diesel energy
consumed in alluvial mining are exhausted in the “grinding mill” stage (67.14%),
other services use 100%, and “mineral excavation” stage uses 99.41% of total
consumption for the entire process. The highest loss of energy happens in the
“services and mineral excavation” stage with a first law efficiency equal to 35.0%.
Comparatively, in alluvial mining technology, energy losses (10.93% of the total
energy input) and total useful energy (89.07% of the total energy input) are presented
in Fig. 7.4. Furthermore, 99.55% of the total energy consumption comes from elecN. A. Cano Londoño et al.
tion methods which depend on the relevant impacts of interest and the chosen
assessment method. Finally, the results are analyzed to aid in the relevant decisionmaking process.
Furthermore, ReCiPe methodology (uses hierarchies, to include long-term
effects) has been chosen to include midpoint indicators, including freshwater
ecotoxicity, freshwater eutrophication, marine ecotoxicity, marine eutrophication,
and water depletion, although these indicators are obviously only related to the
assessments relevant to water-based ecosystems.
7.4 Discussion and Results
7.4.1 Energy and Renewable Input Resources
Environmental impacts associated with energy consumption and water use are
among the most important issues for the mining industry (Pimentel et al. 2016).
Consumption of energy, nonrenewable and renewable resources (water) is clearly
emphasized for each stage listed above, with the challenge being to improve the
efficiency of both mining systems. It should also be pointed out that greater
environmental impacts are expected from the stages with the highest consumption
of nonrenewable and renewable resources. As such it is clear that the global
production-consumption cycles of minerals, water, and energy are inextricably
connected.
7.4.1.1 Energy Consumption in Mining Activity
Northey et al. (2013) suggest characterizing energy consumption by type (electrical,
diesel input for machines, gas) and electricity source (produced on-site or off-site)
to find specific opportunities for improving resource consumption and sustainability
reporting (Northey et al. 2013).
Values for direct and indirect energy consumption provide an approximation of
the electricity, gas, and energy acquired by mines or generated in situ. Figure 7.3
shows energy consumption, energy losses (38.93% of the total energy input), and
total useful energy (61.07% of the total energy input) for open-pit mining systems.
Additionally, 63.56% of the total energy consumed comes from electricity, 35.91%
from diesel, and 0.53% from gas. Highest electricity, gas, and diesel energy
consumed in alluvial mining are exhausted in the “grinding mill” stage (67.14%),
other services use 100%, and “mineral excavation” stage uses 99.41% of total
consumption for the entire process. The highest loss of energy happens in the
“services and mineral excavation” stage with a first law efficiency equal to 35.0%.
Comparatively, in alluvial mining technology, energy losses (10.93% of the total
energy input) and total useful energy (89.07% of the total energy input) are presented
in Fig. 7.4. Furthermore, 99.55% of the total energy consumption comes from elecN. A. Cano Londoño et al.