This is what is called a Wet Scrubber. It job in life is to remove particulate from the air before it is released into the atmosphere. This one removes B class smoke which is produced when you burnt oil or kero. The Scrubber has a massive fan attached that moves some 9000 l/s of air through the Scrubber. Note that the unit has to be maintained on a very regular basis. This includes draining and cleaning the inside and charging with clean water. Plus servicing the fan motor and blower that generates the 9000 l/s to make sure all the bearings are well greased .