Uma metodologia baseada em análise multicritério para seleção de materiais empregados na construção de fornos de produção de carvão vegetal

Abstract

Charcoal plays a fundamental role in the Brazilian steel industry, partially replacing mineral coal in pig iron production. This substitution contributes to mitigating greenhouse gas emissions, making it a competitive advantage in the steel market. However, the costs involved in charcoal production are one of the barriers preventing further increases in this substitution. Part of these costs is linked to using rudimentary and low-technology kilns that result in prolonged production cycles. This study proposes a methodology for material selection in the construction of carbonization kilns, aiming to improve the results of the charcoal production process. The methodology considers fifteen Material Selection Criteria (MSC) that evaluate technical, economic, and environmental aspects. The extended TOPSIS multicriteria method is used to rank the material options. Numerical simulation and fuzzy linguistic terms are employed to determine the values of MSC. The Quality Function Deployment (QFD) and Decision Making Trial and Evaluation Laboratory (DEMATEL) tools are used to determine the weights of MSC. An application example is conducted using the proposed methodology, and multivariate sensitivity analysis is used to evaluate the method's robustness. Additionally, a new constructive configuration for carbonization kilns, which utilizes materials arranged in layers, is proposede, by using a pivoting system, it is possible to change the arrangement of the layers of materials that make up the furnace wall, during the heating and cooling phase. This configuration was evaluated using the proposed methodology, and proved to be superior to the materials commonly used in the construction of charcoal production furnaces, when AISI 1020 steel materials wrapped with a rock wool blanket are used.