995687 - It’s All in the Dust Cake

Filter units (baghouses) are a major component of operating a modern coal, waste, or biomass combustion facility. The operation of the filter unit is critical for reduction in particulate matter emissions. The operation of these units is also critical for the efficient reduction of gaseous pollutants, such as SO2 and mercury. This presentation will focus on studies performed to characterize the impact of baghouse operation and specifically filter media design on the efficient utilization of reagents such as lime and powdered activated carbon in emissions reductions.

The most successful dry FGD plants are associated with optimized bag houses. After the FGD reaction in the main scrubber, a secondary SO2 neutralisation reaction takes place in the dust cake formed on the filter bags in the BH (bag house). An engineered dust cake improves the effectiveness of the neutralization reaction.

Test results performed on specific reference filter bags in large BHs substantiate the importance of a high-quality dust cake. The presentation will provide case studies demonstrating the influence of the filter media design on the SO2 removal. The presentation will also review the impact of the dust cake on the efficient removal of mercury from the gaseous emissions. Selecting a smart filter media can have a significant impact on the operating cost of emissions control equipment.