Sustainability evaluation of agro industrial products, case studies: crange juice and ethanol

Author(s)

Consuelo de Lima Fernandez Pereira

• Document type: Doctoral Thesis
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia de Alimentos
• Defense date: 2008-01-21

Examining board members

Enrique Ortega Rodriguez; Luis Alberto Ambrosio; Leda Coltro; Jose Maria Gusman Ferraz; Maria Silvia Romitelli; Carlos Eduardo Vaz Rossell

• Advisor: Enrique Ortega Rodriguez

Abstract

The objective of the present study was to combine Emergy and Life Cycle Assessment methodologies, used regularly for the evaluation of productive models, to evaluate the sustainability of raw and processed agricultural products, considering the complete productive chain. The combination of these two methodologies allows the evaluation of environmental impacts associated to each one of the chain¿s stages and, also, the evaluation of the renewable and non ¿ renewable demand of resources and, therefore, its viability on the long run. The evaluation was accomplished for two products of great importance for state of São Paulo agriculture: a) productive chain of frozen concentrated orange juice (FCOJ) exported mainly to Europe; and b) productive chain of combustible ethanol produced from sugar cane and consumed in Brazil. Conventional and organic productions of FCOJ were evaluated. The following chain¿s steps were included: agricultural production of oranges, fruit transport and processing to FCOJ, bulk FCOJ transportation (both, road and marine, as well as port operations) dilution and packing in European processing plant. The organic system presented better environmental performance than the conventional system. However, due to the smallest productivity per area, the organic system presented larger consumption of water and land use needed to cultivation per liter of diluted juice. In the two systems, the agricultural stage presented the largest consumption of total resources, while the industrial phase presented the largest consumption of fossil fuel, both direct and indirect. For both systems, the inclusion of more steps in the chain results in worse environmental performance. Moreover, agricultural phase determines the total chain performance. The results indicate that FCOJ chain is not sustainable, although extremely efficient in the use of energy and in the use of residues, even if the organic model is adopted. The agricultural sub-system, for both organic and conventional model, presented poor environmental performance due to the intense use of materials and services. The ethanol chain study was accomplished considering the production in São Paulo and two supply chains: São Paulo and Mato Grosso States. Agricultural phase accounted for the main environmental impacts of ethanol chain. Processing and transportation, due to the consumption of great amounts of resources from economy, reduce ethanol renewability worsening the emergy indices; these phases consume material, particularly fossil fuels. The results also indicate that, since processing and distribution operations consume fossil fuels, ethanol production do emit CO2, and can not be regarded as a CO2 mitigator. Further, the increase in the distance between the producing plant and the consuming center, consequently in the distribution phase, increases the impacts resulting in worse environmental performance. Summarizing, the use of sugarcane ethanol as substitute of fossil fuel presents some advantages in relation to other biofuels. However, its use causes several important environmental impacts. Therefore, production and distribution models should consider these impacts in order not to lose the advantages of using ethanol due to the production model, very intensive, or due to the distribution stage, too extensive (AU)