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 (KGa) at 0.0715 kmol·m–3·kPa–1·s–1, are about ten times higher than conventional devices. Semiempiric equation (R2 = 0.99, p < 0.001) was derived to predict KGa 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.