ABSORPTION OF SO2 AND H2S IN SMALL-SCALE VENTURI SCRUBBERS

Small-scale venturi scrubbers having geometries of typical large-scale units were constructed from glass and were operated in a laboratory system. Carrier gas streams consisting of air or nitrogen and up to 30% (by volume) CO₂ were mixed with SO₂ or H₂S to give SO₂ or H₂S concentrations in the range of 1890-4400 ppm. These gas mixtures were then scrubbed in the Venturis using various injected liquids (plain water, NaOH solutions, NH₄OH solutions, and NaOH/NaHCO₃ solutions) at L/G ratios of 0.0004-0.0040 m³ liquid per standard (1 atm, 60°F)m³ of gas (3-30 gallons liquid per 1000 standard ft³ of gas). Absorption percentages for SO₂ and H₂S were determined as functions of the L/G ratio, initial liquid pH, and liquid composition. The effects of venturi throat length, gas velocity, and the presence of CO₂ in the gas stream were also determined.