The performance of fixed matrix industrial regenerator used for waste heat recovery has been extensively investigated. The melting furnace capacity is 24 ton/day and it is equipped with two regenerators operated alternatively. The performance has been analyzed based on the first and the second laws of thermodynamics. Special attention has been paid to the effect of regenerator cleaning. Measurements have been made before and after regenerator cleaning for air and flue gas temperatures at inlet and outlet, mass flow rates of fuel and combustion air, and the composition of flue gas. It was found that the heat recovered by air is higher in the non-doghouse side. The regenerator cleaning increases the heat recovered by 0.83 and 1.97% for the non-doghouse and doghouse sides, respectively. The effectiveness during the heating period is higher than that of the cooling period. Consequently, it is recommended to use the effectiveness of the cooling period for design and selection of regenerator. The regenerator cleaning was found to increase the effectiveness during the cooling period by 0.78 and 1.56% for non-doghouse and doghouse sides, respectively. Due to regenerator cleaning, the supplied and gained exergy are increased and the second law efficiency is improved by about 3%.
