Desenvolvimento de um sistema integrado de gestão térmica para obtenção de hidrogênio via eletrólise alcalina sob pressão reduzida

Abstract

The growing demand for sustainable energy alternatives makes hydrogen a strategic vector in the decarbonization of industrial and transportation sectors. This dissertation proposes the development of an integrated system for thermal management and enthalpy recovery of hydrogen generated by alkaline electrolysis under reduced pressure. The system is composed of counterflow tube-in-tube heat exchangers, a Venturi injector, and Peltier modules, modeled using finite differences and empirical correlations. The proposal aims to reduce energy consumption through preheating of the electrolytic fluid (50–80 °C) and cooling of hydrogen, which contributes to lowering the reversible voltage, reducing overpotentials, and increasing overall process efficiency. The modeling was implemented in the Python programming language, considering variables such as temperatures, flow rates, geometries, and fluid properties. The hydrogen production rate was obtained based on Faraday’s Law, and the system performance was evaluated by metrics such as reversible voltage, overpotentials, and specific energy consumption. The simulation demonstrated that thermal integration with enthalpy recovery of the electrolytic fluid significantly improves system efficiency at the beginning of the process, reducing specific consumption and increasing the hydrogen production rate. The system proved effective for both heating and cooling, validating the selection of Peltier modules and the configuration of heat exchangers. The results indicate that the approach is functional and replicable, with potential for extension to other geometries and industrial applications. The enthalpy recovery strategy represents a relevant contribution to the advancement of clean hydrogen generation technologies.