Factors Affecting Removal of Sulfur Dioxide from Atmospheres of Table Grapes

Abstract

A portable scrubbing unit equipped with water sprays or a packed column over which water is dripped can be effective in reducing the sulfur dioxide content of fumigation atmospheres. Efficiency of the scrubber in in SO₂ removal is influenced by: 1) amount of water surface exposed to the gas laden air, 2) temperature of the water, 3) use of NaOH in the water as a neutralizing agent, 4) volume of water circulated in a closed system, and 5) use of a flow-through system to provide fresh water during scrubbing. The time required to remove the SO₂ from the room is influenced by: 1) ratio of the volume of air handled by the scrubber to that of the room, 2) efficiency of the scrubber in removing SO₂ on the water surface, and 3) the difference in concentration of SO₂ between the initial concentration and that to which the concentration is to be lowered. Discussed is the application of the "half-scrubbing time" concept of evaluating the significance of the factors affecting time of SO₂ removal and efficiency of the scrubbing unit.