Gas scrubbers are used to control dust, fogs, and odors from industrial emission of gases. They are not only suited for separating pollutants, but also for recovering valuable solids and liquids. The washing liquid may be water, oil, an alkaline solution or alkaline plus hypochlorite solution, depending upon the pollutant to be separate.
The unit is designed on the liquid gas ejector principle. The washing liquid is recirculated by means a centrifugal pump and leave the upper multiorifice nozzle as a set of high velocity jet which induces, clean and conveit the contaminated gas. The velocity of the jets creates a draft so that a fan is therefore not required.
The liquid jets are divided in droplets increasing the mass transfer area and so the scrubbing action. The mixture of liquid and no condensable gas are separated in a downsteam impact type arranged separator. The gas goes upward leaving the tank through a mist eliminator which prevents carry over of contaminated drops on the outgoing effluents.
JET GAS SCRUBBERS
Jet gas scrubbers are suitable for purifying gases and, at the same time, making them circulate. The differential pressure they generate goes from 10 to 150 mm water head. This is very important, because it makes unnecessary to have an electrical fan to extract and blow gases, especially when they are corrosive.
The scrubbing efficiency for acid gases is better than 92% with water, but it can be improved using an alkaline solution. The powders separation efficiency obtained is 99,5% for particles of 20mm and 94% for 2mm ones.
For severe duties, as chlorine scape emergency scrubling units, two scrubbing stages give a reliable exhaust free of pollutants. Also, jet gas scrubber may be combined with a packed tower one attaching a wetting packed bed on the gas outgoing chimney in order to get an efficient and total neutralization.