Natural Gas Intermittent Kiln for the Ceramic Industry: A Transient Thermal Analysis

Abstract

Drying and firing of ceramic products are processes that require high energy consumption. Making these processes more efficient can improve product quality, reduce processing time and energy consumption, and promote economic and environmental gains. In this sense, this work aims to quantify heat transfer in an intermittent ceramic kiln during the heating and cooling stages, with and without thermal insulation. All mathematical formulation is based on the first law of thermodynamics. From the results, we conclude that the greatest heat loss occurs by radiation in the sidewalls of the equipment, and that a considerable amount of energy is required to heat the sidewalls, base, and ceiling of the kiln. Further, with the use of thermal insulation, it was concluded that a high reduction in the heat lost through the sidewalls was achieved, thus providing a global energy gain of approximately 35% and a reduction in the maximum external surface temperature from 249.34 to 79.47 °C when compared to the kiln without thermal insulation, reducing the risks of work accidents and thermal discomfort when in operation.