Produção, beneficiamento e distribuição da Tilápia do Nilo produzida em tanque-rede: uma avaliação energética ambiental.

Abstract

This study includes the analysis of Nile tilapia production, following the Life Cycle Assessment (LCA) methodology. The objective of the thesis was to evaluate the environmental performance in the production of Nile tilapia in different sizes, from nursery, rearing, fattening, processing (in fillet, steak and gutted tilapia) and final transformation of the processing residues into fish meal and oil. , through the quantification of potential environmental impacts, throughout its life cycle, applying the Life Cycle Assessment (LCA), critical points, correction possibilities and increased sustainability of this stage of fish farming were identified. In chapter 1, the reference flow was 1 ton (Mg) of fish. The foreground inventory considered the feed production and the stages of hatching and fish production from the rearing and fattening in cages, while the background inventory considered the production of other material and energy inputs, transport, infrastructure and waste treatment. The categories evaluated were area occupation, water consumption, energy demand, global warming, acidification and eutrophication. In Chapter 2, the reference flow was 1 ton (Mg) of processed and distributed fish. The foreground product system contains the inventory of the Nile tilapia production stages in net cage, processing in a slaughterhouse and distribution to the retail market, while the background product system contains the production inventory of the other material inputs and energy, transport, infrastructure and waste treatment. The categories evaluated were area occupation (AO), water consumption (AC), energy demand (ED), global warming (GW), acidification (AC) and eutrophication (EU). The scenario with Nile tilapia with greater mass had the greatest impact on all categories analyzed. Feed was the main contributor to the categories of energy demand, water consumption and area occupation, while fish farming presented the greatest contribution from eutrophication, acidification and global warming. The production of 1t of processed fish required the following quantities of Nile tilapia: 1.3t in T1200g-E, 2.4t in T1200g-P and 3.3t in T1200g-F. The environmental load of Nile tilapia processed and distributed with the type of eviscerated cut (T1200g-E) was 18 000 m2. year in AO, 54 m3 in AC, 107 000 MJ in ED, 14 500kgCO2eq in GW, 133kgSO2eq in AC and 127 PO43-eq in EU, while these values increased from 33 a 34% in steak (T1200g-P) and 137 to 143% in fillet (T1200g-F). The Nile tilapia production stage presented the highest environmental burden in the evaluated categories (97 to 99%). Given this, we can conclude that smaller fish is a strategy to reduce the environmental impact of tilapia farming, for a more sustainable fish farming is the production of fish of smaller size like 600g to 900g.