In the PBA process flue gas passes in a cross- or counter-flow through a reaction chamber filled with a granular sorbent. Gravity draws the reagent through the reaction chamber, after which it is removed at the bottom of the PBA. The removal performance of a conventional PBA using natural limestone is quite high for SO3 and HF (> 95-98%) but rather limited for HCl (20-30%) and SO2 (10-20%).
A packed bed reactor consists of a vessel filled with reactive material. While passing through the vessel, the pollutants are captured by the filler. The filler needs to be replaced after a certain time, which varies from plant to plant.
The PBA is particular suitable for industrial processes with a peak release of acidic pollutants. Sorbacal® HCG significantly increases the removal performance for HCl and SO2. This makes it an attractive alternative in PBA processes for new applications, like the desulphurization of marine diesel engines.
Sorbacal® C, a natural limestone CaCO3 sorbent in the form of “chippings”, is typically used for PBAs.