BACKGROUND The use of absorbents, based on calcium, for the reduction of sulfur dioxide (SO2) emissions from power plants has been studied for the last 90 years. The present work is part of a research project, which aims at the development of a fixed and a moving bed limestone filter. A filter is placed after the burning, in order to capture SO2 from the flue gases of pulverized lignite combustors. An experimental study and a parametric analysis in a limestone and lignite fixed bed reactor for SO2 capture were conducted in previous works. RESULTS This work studies experimentally the SO2 capture by analyzing the following parameters: inlet mole fraction of SO2, inlet mole fraction of O-2, volumetric flow rate, average temperature in bed, type of calcium carbonate (CaCO3) and length of the solid bed. Under specific circumstances, conversion of SO2 values were found to be greater than 0.99 in the gas outlet for more than 110 min. CONCLUSION Useful conclusions are drawn regarding the behavior of a fixed bed reactor in different conditions. The results highlight the importance of technological interest in the dry process for SO2 capture. (c) 2019 Society of Chemical Industry