Application of principal component analysis (PCA) to the study of the influence of the thermochemical treatment process of tropical wood sawdust on the calorific, mechanical, physicochemical and combustion properties of the resulting fuel briquettes

Abstract

Despite its potential for environmentally friendly energy production, lignocellulosic biomass has less advantageous physicochemical properties that limit its optimal industrial use. This study used principal component analysis (PCA) to evaluate the effects of two thermochemical processing methods (torrefaction and carbonization) on the calorific, physicochemical, mechanical and combustion properties of the resulting biofuels. Various types of tropical sawdust (Dabema, Dibetou, Fraké, Samba and Iroko) are subjected to these treatments, then densified and characterized for energy applications. Specific fuel consumption varies from Samba torrefied (Sam t: 0.69 kg/L) to Samba carbonized (Sam c: 1.48 kg/L). Higher heating values range from Samba torrefied (Sam t: 23983 kJ/kg) to Iroko torrefied (Iro t: 27,442 kJ/kg). Burning speed varies from Samba carbonized (Sam c: 3.07 g/min) to Iroko torrefied (Iro t: 4 g/min). The impact resistance index ranges from 187.5 to 500% for Dibetou torrefied (Dib t) and Samba carbonized (Sam c), respectively. Densities are between Samba carbonized (Sam c: 297.83 kg/m³) and Dibetou carbonized (Dib c: 393.69 kg/m³). The results indicate that these techniques are promising approaches for improving biomass properties. In sum, the PCA reveals that the effect of treatment type on fuel characteristics also depends on the properties of the initial biomass.

Keywords:

• Carbonization
• torrefaction
• lignocellulosic biomass
• principal component analysis (PCA)

Author contributions

Nganko Junior Maimou: conceptualization, methodology, data curation, formal analysis, data processing, draft and original writing. Koffi Ekoun Paul Magloire: conceptualization, methodology, supervision, validation. Kane Moustapha: methodology, supervision, validation. Gbaha Prosper: conceptualization, methodology, supervision, validation and correction. Yao Kouassi Benjamin: methodology, funding search supervision.

Data availability statement

The data associated with this study have not been deposited in a publicly accessible repository. Data will be made available on request.

Ethics declarations

• Review or approval by an ethics committee was not needed for this study because no data of patients or experimental animals was used.

• Informed consent was not required for this study because no clinical data was used.

Disclosure statement

The authors declare that they have no competing financial interests or known personal relationships that would affect the work described in this article.

Highlights of the manuscript

• Biomass benefits from improved calorific , mechanical, combustion and physicochemical properties thanks to thermochemical processing.

• Development of a torrefaction reactor with a rotating chamber.

• Torrefaction increases the higher heating value compared to carbonization.

• Torrefaction produces a much higher mass yield than carbonization.

Acknowledgements

The authors acknowledge and thank the following people and organizations for their support:

1.) Professor Lamine SOW, Director of the Center for Study and Research on Renewable Energies, for making the bioenergy and environment laboratory available for testing.

2.) Africa's center of excellence for the valorization of waste into high value-added products (CEA-VALOPRO), for its technical support.

3.) All the anonymous reviewers who improved the quality of the manuscript through their comments, criticisms and suggestions.

Additional information

Funding

The research that led to these results received funding from the European Union (EU) through the project’s Intra-African Academic Mobility Program (RésIng) under grant agreement [624193 + RésIng]. This study also received technical and financial support from the French development agency through the African center of excellence for waste-to-value products at the Institute National Felix Houphouët-Boigny in Yamoussoukro.