Deactivation of Honeycomb SCR Catalysts in High-Arsenic Coal-Fired Power Plant

Abstract

In this paper, the arsenic deactivation of honeycomb Selective Catalytic Reaction (SCR) catalysts in Huolinhe coal-fired power plant were studied. The denitrification activity of catalyst were tested and assessed at different time points of its life cycle. In addition, by utilizing X-ray fluorescence spectrometer, N2 adsorption-desorption, mercury porosimetry and automatic chemisorption analyzer (NH3-TPD and H2-TPR), the chemical compositions and physicochemical properties of the catalysts were explored and analyzed. As it is shown from the results, the deposition of arsenic in the surface and micro pores of the catalysts led to the decrease of specific surface area and acidity of the catalyst, which was the major reason for the poisoning of the catalyst. Bench-scale catalyst test results show that the activity of catalysts dropped down to 69% of the new catalysts after only about 1 000 hours service, suggesting a very fast deactivation process compared to normal catalyst. To extend the catalyst lifetime, certain procedures for catalyst lifetime managements were proposed to slow down the arsenic poisoning process in the coal-fired power plant fueled with high-arsenic coal.

Keywords

• coal fired power plant
• huolinhe coal
• high-arsenic coal
• selective catalyst reduction
• denitrification activity
• arsenic posion
• catalyst lifetime management