Abstract :
[en] The aim of this study is to have a good understanding of the environmental impact of glucose production. Glucose is generally produced from corn or wheat. Since agricultural processes are known to be difficult to evaluate by LCA, the results obtained with two different LCA databases, Gabi and EcoInvent, are compared in this work.
The production of glucose from raw materials can be divided in two steps: the agricultural step allowing the cereal production, and the conversion step including the extraction of the starch from the plant and its hydrolysis into glucose. Preliminary results underline the high impact of the agricultural step, so a special attention has been paid to these data. Specific Belgian data collected by the Walloon Agricultural Research Centre (CRA-W) (2014) [1] have been used as primary data (yield, amount of fertilizers, etc.), either using EcoInvent or Gabi datasets background data to model fertilizers, diesel consumption, etc. A third model was built using only data available in Ecoinvent for corn and wheat cultures. For the conversion steps, literature data have been used along with some industrial data.
Based on these multiple sources, it is possible to compare the LCA results for the production of 1 kg of glucose for three different cases. The results underlined that the differences between the two databases are smaller than the differences between specific data (Belgium data) or non-specific data (Ecoinvent) for the agricultural steps. Nevertheless, in some impact categories, the differences between the two databases remain high. The presentation will underline where these differences are coming from. This leads to also analyze the differences between background data such as energy generation or fertilizer production.
Moreover, special attention has been put on the influence of long-term emissions, in the Ecoinvent database. As these emissions have a large influence in some impact categories, we have to clarify if we should include them or not in view of comparison with GaBi database. Moreover, the Ecoinvent model and the GaBi models have been realized in two different software (Simapro and GaBi, respectively), therefore, some checks have been performed to see if some differences can be induced by the software.
In conclusion, this presentation will underline which is the sensibility of the results to parameters not controlled by the LCA practitioner, such as the datasets hypotheses, the software differences, etc.
1. Walloon Agricultural Research Centre (CRA-W), ALT4CER project. 2014.