Sustainable Group Decision Support System for Selection Biochar Based on the Pyrolysis Process

Abstract

Biochar is one of the advanced research trends nowadays. The production of biochar by thermochemical methods from various biomass wastes has greatly contributed to reducing emissions and improving soil quality. The study aims to evaluate and select three main types of biochar taken from waste residues such as sawdust, soybean straw, and Chlorella vulgaris under temperatures ranging from 300 to 800 °C. However, the selection process between different types of biochar using pyrolysis was a major challenge. The proposed decision-making methodology in this study is applied in two stages; 1) Calculating the weights of the selected criteria using the Fuzzy Analytic Hierarchy Process (AHP). 2) Selecting the best alternatives for biochar types using the Order Preference by Similarity to Ideal Solution (TOPSIS), method and the VIekriterijumsko KOmpromisno Rangiranje (VIKOR) method. The results showed that the optimal type of biochar is Soybean Straw (SS) at a temperature of 800 °C using the TOPSIS technique. While VIKOR technique selected the alternative Chlorella Vulgaris powder (CL) at 300 °C as the best alternative. In contrast, five scenarios of sensitivity analysis were conducted to rank each technique based on changing the weights of the criteria. Changing the weights of the criteria had a significant impact on the ranking of the alternatives for VIKOR and TOPSIS techniques, which represented the highest sensitivity.

Keywords: Biochar, F-AHP, TOPSIS method, VIKOR method, Sustainability