**5. Conclusions**

Evaluating each category separately, AD was shown as the best alternative for GWP and the other four categories, including ADf, ODP, HTP, and MWTP. The use of extracted pomace as fuel (OPOE-B) instead of natural gas (OPOE-A) could strongly reduce GWP but, conversely, increase the impact in the other two categories, i.e., HTP and EP, leaving the rest without change or with a negligible increment (FWTP, TEP). More specifically, the refining process of crude oil had a very low contribution compared to the extraction process. After evaluating the three alternatives with normalized results and applying a weighting factor of 1, AD showed a global environmental impact reduction of 88.1 and 85.9% with respect to crude olive pomace oil extraction using natural gas and extracted pomace as fuel, respectively.

**Author Contributions:** Conceptualization, B.A.-F. and M.R.-G.; methodology, B.A.-F. and A.O.; formal analysis, G.E.; resources, G.R.-G. and A.S.; writing—original draft preparation, B.A.-F.; writing—review and editing, J.F.G.-M., A.S., and F.G.F.; supervision, G.E.; funding acquisition, F.G.F. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by the Spanish Ministry of Economy and Competitiveness by Project CTM2014-55095-R.

**Acknowledgments:** The authors thank Maria Victoria Ruiz Méndez and Rafael Borja Padilla, research members of the Instituto de la Grasa, Spanish National Research Council (CSIC), for their kind help in the inventory data collection of this work.

**Conflicts of Interest:** The authors declare no conflict of interest.

### **References**


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