The unit operates as follows. The exhaust gas to be cleaned enters the scrubber axially at the bottom, then flows vertically up through a packed bed column, which is supported by a fixed grate.
The scrubbing liquid is fed in from the top counter flow and cascades over the bulk filling material, which makes up the packed bed.
The filling materials designed to give a high surface area and still retain a high free volume, thus allowing intimate contact between the scrubbing liquid and the gas with low overall pressure drop.
The scrubbing liquid is collected in the bottom of the unit, where it is removed for further processing.
A demister pad is situated in the top part of the column to coalesce the mist droplets and prevent them from being carried over in the cleaned gas. The cleaned gas leaves the scrubber, either vertically or horizontally, depending on the site conditions and requirements. The filing material in the packed column is selected from a number of different shapes to suit the particular application and is chosen to give a high scrubbing efficiency and good operating performance.
In addition to the Raschig rings used as a bulk filling material, there are now a number of newly developed technical shapes with a very high efficiency, particularly in the size range 40 to 80mm. With these new shapes, a surface area of up to 130m2 per cubic metre of material is attained with a free volume of over 93%.
The size of column is chosen to suit the needs of the particular application and a number of columns may be required, each with a different scrubbing liquid in order to achieve the required level of gas cleaning. This could include absorption desorption and odour elimination.
The packed bed scrubber is susceptible to pollution by dust, which becomes deposited in the bulk filling material and if allowed to do so, could eventually clog the entire column. For this reason, the Packed Bed Scrubber is not used when the dust load is significant.
The FKL packed bed column represents an alternative to the vertical configuration. In this arrangement the gas flow is horizontal and flow of the scrubbing liquid is vertical. This arrangement is generally used where there is a lack of vertical space.
Typical Applications of Wet Scrubbers - Packed Bed FK Series
Luehr Filter Australia Pty Limited | Engineered Dust & Fume Control Solutions
For over 35 years Luehr Filter has become a trusted name in Australia’s mining and resources sector for providing the highest quality products for air pollution and gas treatment systems in a wide range ...