Sara Ester Díaz Guzmán

I am a PhD student in the Department of Process Engineering of the University of Las Palmas de Gran Canaria, in Spain. The main theme of my research work is in the area of the valorisation of banana by-products, which I am investigating at the Research Group Integrated and Advanced Manufacturing (CFI). The research group was founded in 2000, but since 1990 (as Integrated Manufacturing Service and Integrated Manufacturing Laboratory) it has been working within the local industry in advanced manufacturing technologies, research and technical support. This group consists of professors and researchers from the areas of Industrial Design, Mechanical and Chemical Engineering.  

One of the major areas of interest in which the group has been working along the last years is the valorisation of wastes from banana plantation. Banana is one of the most important symbols of the Canary Islands and an essential pillar from the economical point of view. Its cultivation is accompanied by the generation of a great amount of wastes, usually left in the plantation. Making use of this biomass could be a very attractive alternative, contributing to the preservation and adding value to the fruit production matrix. The expertise and capabilities possessed by the CFI have led it to be involved in projects related to the extraction and conditioning of natural fibres from banana plant pseudostem for their valorisation, mainly in composites. 

During the fibre extraction, a low value by-product is generated: the pulp (BPP). In my research work I explore the upgradability of the BPP into valuable products.  

Thanks to BRISK2 I had the opportunity of visiting the Rig 1 of National Laboratory of Energy and Geology (LNEG) in Lisbon. This rig is especially dedicated to the biomass pre-treatment, and it has all required facilities for process development and feedstock and product characterization. 

The purpose of the visit was to evaluate the impact of autohydrolysis on banana pseudostem pulp. Oligosaccharides production, residual cellulose digestibility and the generation of by-products were evaluated. During the ten-day visit at LNEG, the planned activities were successfully completed. The raw material was milled in a knife mill yielding chemically homogeneous fractions, as determined by the project consensus analytical procedures. Autohydrolysis was assayed both using an isothermal (mini pressure-reactors) and a non-isothermal (2-L stainless steel stirred reactor, Parr Instruments Company, USA) approach, yielding complementary results, that will be presented in an international conference.  

The autohydrolysis process induced the production of oligosaccharides as the main soluble products together with pre-treated solids. Both these products may have potential applications in the energy and chemical, food or feed industries.  

To conclude, I would like to highlight that thanks to BRISK2 I have had the opportunity not only to access to unique equipment but also to gain knowledge in the field of the biomass autohydrolysis, thanks to the high experience of the member of the hosting institution. This experience has provided also the opportunity of possible future international co-operation between the two institutions. 

Acknowledgments 

I would like to thank all the kind personnel at LNEG, particularly Dr Luís C. Duarte, Dra. Florbela Carvalheiro, Dra. Patrícia Moniz and Diogo Costa, for their dedication, valuable comments on my experiments and taking care of me during my stay.