عنوان مقاله [English]
This work presents an investigation of a mobile bed scrubber in removal of hydrogen sulfide from a typical flue gas by aqueous ferric chelate solution. The experiments were conducted at different operating conditions (gas flow rate: 22-28 lit/min, ferric chelate flow rate: 0.2-0.5 lit/min, hydrogen sulfide concentration: 300-4000 ppm, static bed height: 13, 23 cm and packing diameter: 2, 2.5 cm). The results show that the H2S absorption rate increases by increasing static bed height. This is because the contact time and surface area between gas and liquid phases increase by increasing the static bed height. Also, H2S absorption rate increases by increasing ferric chelate solution flow rate due to the greater number of ferric ion (Fe3+) moles available for reaction. The pressure drop also increases by increasing static bed height and catalyst solution flow rate. Therefore, these parameters have to be increased in a restricted range. Under investigated conditions, the results show that by increasing the packing sizes (diameter), H2S concentration and flue gas flow rate, the H2S concentration increases in the product gas. This is due to decreasing the contact surface area, Fe3+ to H2S molar ratio and residence time, respectively. The liquid to gas flow rate (L/G) ratio is one of the major parameters affecting the design of mobile bed scrubber. In this work, considering the obtained experimental data, this parameter is determined in the range of 8-21 lit/m3 depending on the H2S concentrations range in flue gas and packing diameter.