Study of thermal transition in brick kilns: modeling wood consumption and energy efficiency

Abstract

The production of fired bricks in traditional wood-fired kilns is a common practice, particularly in developing countries, where it holds cultural and economic significance. However, this method raises environmental and health concerns because of its often low energy efficiency and high fuel consumption. This study aims to model the thermal transition in these traditional kilns to optimize the firing process, reduce wood consumption, and improve energy efficiency. The brick firing process, which includes a critical transitional phase of temperature rise, is frequently poorly managed, leading to significant thermal losses and incomplete combustion. A systematic approach is needed to analyze and improve thermal management, considering factors such as brick stacking, kiln geometry, and combustion parameters. We develop a thermodynamic model that simulates heat transfer, incorporating equations of conduction, convection, and radiation. This model relies on simplifying assumptions that facilitate resolution while maintaining sufficient accuracy. The results revealed a rapid temperature increase followed by stabilization, revealing a dynamic balance between energy input and thermal loss. Our simulations indicate that wood consumption initially increases to reach a plateau when the temperature stabilizes. However, energy efficiency gradually declines, highlighting the importance of optimizing heating and combustion conditions to minimize losses. This research is crucial for small producers, as it could yield significant economic and environmental benefits by enhancing the energy efficiency of brick production. The findings of this study underscore the complex interactions among temperature increase, wood consumption, thermal loss, and energy efficiency. Optimizing thermal parameters, such as heating duration and heat distribution, is essential to reduce reliance on forest resources and improve the sustainability of traditional production methods. These findings pave the way for innovations in brick kiln technology, promoting more environmentally friendly construction practices.