Study of boron behaviour in two spanish coal combustion power plants

► The fate of Boron during coal combustion was investigated. ► A sample preparation procedure for B analysis in coal and by-products was optimised. ► 95% of the incoming boron was collected in the fly ashes. ► The co-combustion of pet-coke produces a decrease in the ESP B removal efficiency. ► The remaining gaseous boron was eliminated via the FGD in the wastewater.