Deactivation and Regeneration of High-Dust SCR Catalyst Operated in High Percentage Biomass CoFired Coal Units

摘要

The co-combustion of large amounts of biomass in bituminous coal-fired unit's results in significantly increased deactivation rates of catalyst in high-dust SCR reactors. The rapid deactivation is caused by catalyst poisons contained in the biomass and poses new challenges for catalyst management as well as catalyst regeneration. In case of E.ON's 1,080 MWei bituminous coal-fired Maasvlakte Power Station in the Netherlands, a co-combustion of 20% biomass based on heat input results actually in a frequent need to exchange 50% of the catalyst fill and regeneration of the removed catalyst. The causes and rates of catalyst deactivation as a result of 20% biomass co-combustion as well as their successful removal by means of advanced catalyst regeneration and the restoration of the catalyst's activity while maintaining an adequate low SO2/SO3 conversion rate are presented.