The High Removal Efficiency of H₂S by MDEA Solution in High-Jets Oscillating Purifier

Hydrogen sulfide (H₂S) is an extremely noxious impurity generated from industrial processes, but conventional absorption devices applied to remove H₂S are often constrained by low mass transfer coefficients and large equipment volume. To overcome these limitations, we propose a novel high-jet oscillating purifier (HOP) and systematically investigate the key operational parameters that influence desulfurization performance when HOP is combined with a methyl diethanolamine (MDEA) solution. Experimental results demonstrated that H₂S removal efficiency and mass transfer coefficients increased with absorption flow rate (0.06-0.12 m³/h), methyl diethanolamine concentration (0.8-3.2 wt %), and inlet H₂S concentration (20-160 mg/m³), but decreased with methyl diethanolamine solution temperature (25-85 °C). Intriguingly, inlet gas flow rates (5 and 17 m³/h) improved removal efficiency but reduced mass transfer coefficients. Radial injection (α = 0°) of absorption liquid achieved optimal performance, yielding peak efficiency at 98.7%, surpassing nonradial injection (α = ±45°) by 12.3-15.8%. The mass transfer coefficients (<i>K</i> _G <i>a</i>) at 0.0715 kmol·m^-3·kPa^-1·s^-1, are about ten times higher than conventional devices. Semiempiric equation (<i>R</i> ² = 0.99, <i>p</i> < 0.001) was derived to predict <i>K</i> _G <i>a</i> across operational conditions. The industrial application indicated that HOP achieved an average removal efficiency higher than 95.1% with only 1/8 of the device volume compared to conventional scrubbers. The study indicates that HOP combined with MDEA solution has great potential for application in removing H₂S for industrial plants.