Carbon Footprint of Food Waste Management: A Case …
37
To evaluate the advantages of investing in AD treatment, Chen et al. [9] assessed
the environmental and economic analysis through a quantitative and comprehensive
evaluation of food waste, which was conducted in food waste-based methane plant
located in China. When only methane production was considered, the net energy
output (186.01 MJ) was slightly higher than the net energy input (167.47 MJ),
implying that AD was a clean energy producing technology. Besides, they indicate the global warming potential (GMP100) of 96.97 kg CO 2 e.t
−1 of food waste
treated.
Fan et al. [17] evaluated the carbon footprint of organic waste treatment by
reviewing pre-treatment and post-treatment approaches which complement the AD
process in order to ensure the desired quality of biosolids and biogas, as by-products.
The carbon footprint was calculated based on energy consumption and considered
the processes pre-treatment, digestion process, post-treatment, waste collection and
transportation. They concluded that, for the AD operation to be sustainable, the sum
of the benefits by the utilization of biogas and biosolids needs to overcome the impacts
from total AD operation, including the pre-and post-treatment and the transportation
activities.
In order to deeply evaluate the carbon footprint of food waste, Scholz et al. [38]
applied this approach to a case study in Swedish supermarkets. This carbon footprint
analysis is conducted from cradle up to the retail stage of the food supply chain,
including delivery. The results indicated a wastage of 1570 t of fresh food (excluding
bread) in the six supermarkets, which has a carbon footprint of 2500 t CO 2 . The fruit
and vegetable and the meat departments contributed to 46% and 29% of the total
carbon footprint of food waste, respectively.
On the same hand, Marrucci et al. [30] evaluated the environmental performance
of an Italian supermarket waste management system, through its carbon footprint and
compared the environmental impacts in terms of CO 2 e of different waste treatments
for each waste category. They found that anaerobic digestion releases less GHG
emissions and this type of treatment is a great initiative to significantly reduce the
environmental impact of a retail supermarket.
Moreover, it is worthy to mention some studies addressing the GHG emissions
analysis not only related to the organic fraction of MSW but for all the MSW management of a city. In this respect, Itoiz et al. [27] presents the “Zero Waste” tool, called
CO2ZW, which produces a GHG emissions inventory from MSW of Mediterranean
European countries. This tool considers the key stages and parameters for the GHG
emissions calculation and follows the IPCC guidelines for national inventories, which
is based on life cycle assessment (LCA) principles. The authors indicate that, with
the CO2ZW tool, it is possible to evaluate the waste management infrastructures and
policies, along with the quantification of GHG emissions from MSW management
activities. Because of that, the GHG emissions quantification is essential to guide
solid waste policy and climate change solutions.
Pérez et al. [33] applied the carbon footprint based on LCA approach to calculate
the GHG emissions from the MSW treatment stage using Madrid City as a case
study. The methodology takes into account the direct GHG emissions produced in
waste treatment, the indirect GHG emissions related to the use of electricity, and the
37
To evaluate the advantages of investing in AD treatment, Chen et al. [9] assessed
the environmental and economic analysis through a quantitative and comprehensive
evaluation of food waste, which was conducted in food waste-based methane plant
located in China. When only methane production was considered, the net energy
output (186.01 MJ) was slightly higher than the net energy input (167.47 MJ),
implying that AD was a clean energy producing technology. Besides, they indicate the global warming potential (GMP100) of 96.97 kg CO 2 e.t
−1 of food waste
treated.
Fan et al. [17] evaluated the carbon footprint of organic waste treatment by
reviewing pre-treatment and post-treatment approaches which complement the AD
process in order to ensure the desired quality of biosolids and biogas, as by-products.
The carbon footprint was calculated based on energy consumption and considered
the processes pre-treatment, digestion process, post-treatment, waste collection and
transportation. They concluded that, for the AD operation to be sustainable, the sum
of the benefits by the utilization of biogas and biosolids needs to overcome the impacts
from total AD operation, including the pre-and post-treatment and the transportation
activities.
In order to deeply evaluate the carbon footprint of food waste, Scholz et al. [38]
applied this approach to a case study in Swedish supermarkets. This carbon footprint
analysis is conducted from cradle up to the retail stage of the food supply chain,
including delivery. The results indicated a wastage of 1570 t of fresh food (excluding
bread) in the six supermarkets, which has a carbon footprint of 2500 t CO 2 . The fruit
and vegetable and the meat departments contributed to 46% and 29% of the total
carbon footprint of food waste, respectively.
On the same hand, Marrucci et al. [30] evaluated the environmental performance
of an Italian supermarket waste management system, through its carbon footprint and
compared the environmental impacts in terms of CO 2 e of different waste treatments
for each waste category. They found that anaerobic digestion releases less GHG
emissions and this type of treatment is a great initiative to significantly reduce the
environmental impact of a retail supermarket.
Moreover, it is worthy to mention some studies addressing the GHG emissions
analysis not only related to the organic fraction of MSW but for all the MSW management of a city. In this respect, Itoiz et al. [27] presents the “Zero Waste” tool, called
CO2ZW, which produces a GHG emissions inventory from MSW of Mediterranean
European countries. This tool considers the key stages and parameters for the GHG
emissions calculation and follows the IPCC guidelines for national inventories, which
is based on life cycle assessment (LCA) principles. The authors indicate that, with
the CO2ZW tool, it is possible to evaluate the waste management infrastructures and
policies, along with the quantification of GHG emissions from MSW management
activities. Because of that, the GHG emissions quantification is essential to guide
solid waste policy and climate change solutions.
Pérez et al. [33] applied the carbon footprint based on LCA approach to calculate
the GHG emissions from the MSW treatment stage using Madrid City as a case
study. The methodology takes into account the direct GHG emissions produced in
waste treatment, the indirect GHG emissions related to the use of electricity, and the