A Predictive Model for the Anisotropy Index of Semi-Coke Derived from the Properties of Colombia's Eastern Cordillera Coals

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Eliana Romero-Salcedo https://orcid.org/0000-0001-5369-3566
Sandra Manosalva-Sánchez https://orcid.org/0000-0001-9879-0933
Wilson Naranjo-Merchán https://orcid.org/0000-0002-9123-0308
Oscar García-Cabrejo https://orcid.org/0000-0002-7396-8915
Mauricio A Bermúdez https://orcid.org/0000-0003-0584-4790
Juan Gómez-Neita https://orcid.org/0000-0001-9967-7123


Coal, coke anisotropy quotient, semi-coke, principal component analysis, textural component, Colombia Eastern Cordillera


This study developed a theoretical model for the determination of the Coke Anisotropy Quotient (CAQ) of semi-coke from the properties of its precursor coal. This is an useful parameter to define the resistance and reactivity of semi-coke in the blast furnace. For 36 semi-coke samples, a textural analysis was performed alongside a fluidity test to determine the real CAQ. The main textures observed were: isotropic and circular for high volatile bituminous coals (HVB); lenticular and fine ribbons for the medium volatile bituminous coals (MVB); and medium and thick ribbons for the low volatile bituminous coals (LVB). The CAQ varied in a range from 1 to 11. A principal component analysis (PCA) and multiple regression allowed to discriminated the importance of certain coal properties, in determining the CAQ to be recognized and to estimate parameters of the mathematical model. The statistical analysis suggested that CAQ can be best predicted from the fluidity, volatile matter, and Ro of the parent coals. The veracity of this model result was then tested using a second dataset from Poland. This work optimizes the usefulness of standard datasets in the prediction of CAQ's offering a means of quality control that could be implemented in Colombian coke production.


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