Evaluation of Flue Gas Denitration Catalyst

Routine testing and evaluation of denitration catalyst performance are important approaches for effective operation and management of flue gas denitration system.A selective catalytic reduction (SCR) denitration catalyst used in a power plant in Xiamen was investigated in this study.The surface activity,microscopic properties and surface deposit of the catalyst were tested.It was found that:the activity (K/Ko) of the catalyst was 0.72 afrer 25 144 hours of operation.Almost no pores in the used catalyst had a channel diameter less than 3.5 nm.The specific surface area reduced significantly to 13.5％ 17.7％.Loss of VOx compound was observed.Crystal particles showed some degree of conglomeration.Further study found that the concentrations of Ca2+,Na+,K+ and P deposited on the surface of the used catalyst were 4.5-5,115-140,4.6-5.7,and 7.4-7.9 times of that on fresh catalyst,respectively.Accumulation of Arsenic (As) on the catalyst was also found.The research methods adopted in this study and the results of the experiments are useful for developing catalyst testing and evaluation program in China.They may play an important role in optimizing the operation of flue gas De-NOx system,selection of regeneration process,increase of catalyst life time,and reduction of operation cost.