Wet Scrubbers for Fume Cupboards

Packed Bed Wet Scrubbers

The units are packed bed wet scrubbers utilising both co-current and counter-current gas scrubbing technologies. Co-current: gas and scrubbing liquor flow in same direction. Counter-current: gas and scrubbing liquor flow in opposite directions. The unique design of the APMG Plastics unit ensures that the gas is in intimate contact with the wetted packing media for the maximum amount of time. The depth of the packing is equivalent to 2.5 metres.

Superior efficiency and dependability make this fume cupboard fume scrubber ideal for a wide array of applications including chemical, mineral and metal analysis and inspection. Product reliability is already proven with a number of units currently serving fume cupboards used on a 24 hour cycle with extensive exposure to strong acids.

Wet Scrubber Process

The air flow from the fume cupboard (or other source) is split into 2 equal air streams before entering the fume scrubber at the top of the two outer co-current packed sections. The air passes through a Vane-type mist eliminator before entering the random packed bed of 1” Pall rings. The air flow travels downwards through the wetted packing before turning through 180° into the central chamber. Here the divided air streams come together before passing vertically upwards (counter-currently) through the central wetted packed bed. Having passed through this section and the spray distribution above the packing media the processed airstream enters and passes through a vertical droplet separator before exiting the unit through the flanged outlet connection.

The scrubbing liquor is re-circulated around the scrubber via a magnetically driven polypropylene pump and a PVC pipework system. The base of the unit forms a sump for the re-circulation liquor. The liquor within this reservoir is maintained at a constant level by the continuous addition of fresh water from the automatic fill valve and chemicals from the optional pH dosing system. This counteracts the effect of both evaporation and neutralisation. The sump contents must be regularly disposed of in a suitable chemical drainage system or collection tank to control salts build-up and maintain a fresh scrubbing solution.

The fume scrubber unit is constructed from corrosion resistant plastic materials (polypropylene and PVC), ensuring the fume cupboard can remain fully operational within aggressive chemical environments.