Hygrade’s packed tower scrubbers are built to the counter-flow principle, cleaning soluble and noxious gases with a scrubbing liquor as they pass through inert media.

The gas or air stream travels up the tower, meeting downward flowing scrubber liquid. Gas absorption comes either through physical contact and the dissolution of gas in water, or by the chemical reaction between gas and scrubbing reagent.

Key to efficiency are the packing surface area of the gas or liquid transfer, even distribution of the scrubbing liquor throughout the packing and the gas velocity and liquor flow rate throughout the packed bed.

Gases removed by these types of scrubber include hydrogen chloride, ammonia, nitrogen oxides, sulphur dioxide, phosgene, chlorine, hydrogen sulphide, amines, bromine, nitric acid, methanol and formaldehyde.

The base section, or sump, acts as a liquid reservoir linked to the recirculation pump inlet, with further connections for adding water, chemical doses and draining spent liquor.

Gas absorption occurs throughout the packed bed section where loose, random packing for optimum scrubber performance, is supported on a purpose-built packing plate.

The upper section comprises a liquid distributor to ensure even spread across the packing, with a droplet eliminator preventing carry over. This can be a vertical or horizontal design, depending on the outlet or discharge requirement.