In short a scrubber system basically removes harmful materials from exhaust gases before they are released into the environment or atmosphere. There are two types of scrubbing methods. There is wet and dry scrubbing. Both systems work in similar ways and have the same end result. That is to change a toxic chemical into something less toxic or non-toxic. Now scrubber systems rely on a chemical reaction with a sorbent (which is a material that sorbs another substance or A substance that has the property of collecting molecules of another substance by sorption.; that is to say that it has the capacity or tendency to take it up by either absorption or adsorption (The accumulation of gases, liquids, or solutes on the surface of a solid or liquid. It is basically a type of Chromatography method which is usually a technique for separating and or identifying the components in a mixture). Like I was saying before scrubber systems rely on a chemical reaction with a sorbent to remove a bunch of toxic or harmful chemicals, like sulphur dioxide (SO2), acid gases, and air toxics, from the flue gas (which is the smoke from the fire of a boiler which is made up of mainly carbon dioxide, carbon monoxide, and nitrogen). The sorbent that they normally use is limestone (CaCO3). When the limestone is crushed into a powder, they then mixed it with water(H2O) and spray it into the gases from burning coal. This solution then captures the toxic sulphur gases (SO2) and pulls them out and all that is left is a dry powder. This is the basic functions of any type of scrubber system to prevent sulphur from being released into the atmosphere. Another example of a common sorbent is Alumina (Al2O3) another sorbent that is use in scrubbers. It can neutralize hydrogen chloride gas (HCl(g))and other pollutants.
CaCO3+ H2O Ca(OH)2 + CO2
Ca(OH)2 + SO2 CaSO3 + H2O
Al2O3+ HCl(g) AlCl3 + H2O.
In a wet scrubber, a liquid sorbent...