Biochar is found to possess a large number of applications
in energy
and environmental areas. However, biochar could be produced from a
variety of sources, showing that biochar yield and proximate analysis
outcomes could change over a wide range. Thus, developing a high-accuracy
machine learning-based tool is very necessary to predict biochar characteristics.
In this study, a hybrid technique was developed by blending modern
machine learning (ML) algorithms with cooperative game theory-based
Shapley Additive exPlanations (SHAP). SHAP analysis was employed to
help improve interpretability while offering insights into the decision-making
process. In the ML models, linear regression was employed as the baseline
regression method, and more advanced methodologies like AdaBoost and
boosted regression tree (BRT) were employed. The developed prediction
models were evaluated on a battery of statistical metrics, and all
ML models were observed as robust enough. Among all three models,
the BRT-based model delivered the best prediction performance with R
2 in the range of 0.982 to 0.999 during the
model training phase and 0.968 to 0.988 during the model test. The
value of the mean squared error was also quite low (0.89 to 9.168)
for BRT-based models. SHAP analysis quantified the value of each input
element to the expected results and provided a more in-depth understanding
of the underlying dynamics. The SHAP analysis helped to reveal that
temperature was the main factor affecting the response predictions.
The hybrid technique proposed here provides substantial insights into
the biochar manufacturing process, allowing for improved control of
biochar properties and increasing the use of this sustainable and
flexible material in numerous applications.