Análise do ciclo de vida (ACV) do gasóleo versus biodiesel de jatropha

Abstract

This study compares the environmental impacts of an internal combustion engine using diesel versus jatropha biodiesel, analyzing the life cycle of both fuels. The scope of the life cycle analysis was defined using a "cradle-to-grave" approach, which considered the stages of raw material extraction, fuel processing or production, transportation for refueling, and combustion or use in the engine. The functional unit of 1,000 km travelled by a vehicle powered by a diesel engine was adopted to ensure a fair comparison. The data used to compose the inventory were primarily sourced from the SimaPro v.9.6.0.1 software, while others were obtained through bibliographic references, which are considered secondary data. The comparison of the product systems (diesel engine and jatropha biodiesel engine) was performed using the SimaPro v.9.6.0.1 software program, employing the ReCipe method in the 2016 update version. The two approaches of the chosen method were used: ReCipe midpoint and ReCipe endpoint. With the ReCipe endpoint approach, it was possible to select the most relevant impact categories for the comparative analysis, and with the ReCipe midpoint approach, the impact analysis and comparison of the two product systems were performed. By assigning scores to the impact categories, it was observed that, overall, the use of jatropha biodiesel generates fewer environmental impacts. This result is interesting for the Mozambican context, as it may motivate investment in this fuel as an alternative to fossil fuels. To complement this study, an economic comparison was made, taking into account the cost per unit of useful energy for each fuel. Jatropha biodiesel was found to be more expensive, revealing a challenge that requires further study to assess the economic viability of investing in this fuel.