Análise do processo de gaseificação do plástico PET utilizando o modelo de equilíbrio químico

Abstract

This study aims to present analyses of improvements in the energy generation process through gasification using the Waste to Energy) (WTE) system with the purpose of exploiting the energy potential of municipal solid waste that is lost when deposited in landfills and open-air dumps. The analysis will be conducted using plastic as a raw material, aiming to assess the energy efficiency of the generated synthesis gas, thus highlighting the process as an alternative for plastic recycling. The plastic gasification reaction uses the pyrolysis process, one of the stages of gasification, which occurs at low temperatures and the intermediate result is the Synthesis Gas (Syngas), also known as Producer Gas, a synthesis gas whose products are hydrogen (H2) and carbon dioxide (CO2). This gas is intermediate in energy generation and can be converted into usable products, such as electricity, heat, fuel, or chemicals. The gasification process is a thermal energy conversion, where it acts on the depolymerization of plastics, breaking their polymer layers, and this thermal conversion is carried out using catalysts. The gasification analysis will be performed through the chemical equilibrium approach using Gibbs free energy and stoichiometric equations, with the assistance of a Python programming code. The variation of parameters that influence the Syngas efficiency, such as temperature, humidity, calorific value, reagent quantity, and variations in its composition, will be evaluated. For reasons discussed in this study, plastic gasification is environmentally beneficial compared to landfill and open-air dumps. It is expected to achieve a high process efficiency, thus increasing the calorific value of Syngas, making it richer and of higher quality, consequently generating a product with greater energy potential. An advantage is that plastics, by their nature, already possess a high calorific value due to their composition.