Reduction of sulphur emissions in a tunnel kiln

This study is focused on the study of the sulphur emissions arising from a tunnel kiln firing bricks and fuelled by petroleum coke. The emission analysis identified that the most critical pollutants to comply with environmental standards are sulphur oxides. The work has been carried out in two phases. In the first part, a balance of sulphur in the kiln was performed, and the physical-chemical transformations of sulphur compounds were studied, noting that there is a significant adsorption of sulphur compounds in the processed material, which reduces the final emissions of SO2, albeit insufficient to meet the emission limit value established by law, if no changes in the raw materials and/or the fuel are introduced. Thus in a second phase the application of a cleaning system for reducing SO2 emissions was proposed. Specifically, the implemented system is based on the use of calcium hydroxide as a reagent and a bag filter as a gas-solid separator. These systems have highly variable efficiencies (between 10 and 80%) for the removal of sulphur oxides, depending on the design and operating conditions. In the studied case the reached efficiency was about 75%. (Author) 29 refs.