Integrated Dust Removal and Denitration Using a Dual-Layer Granular Bed Filter with SCR Catalyst

Abstract

To solve the issues of serious wear, blockage, and poisoning of the catalyst in the denitration process of industrial furnaces such as glass furnaces and cement kiln, it was proposed to integrate the high-temperature dual-layer granular bed filter and the selective catalytic reduction (SCR) reactor into a device to realize the denitration of the SCR catalyst in a dust-free state. In the device, the upper part was a dual-layer granular bed filter and the lower part was a V2O5-WO3/TiO2 honeycomb ceramic catalyst. In the self-built dust removal and denitration integrated test equipment with an inner diameter of 100 mm, the effects of flue gas temperature, flue gas flow rate, nitric oxide (NO) concentration, and catalyst height on the denitration efficiency of the catalyst were investigated by orthogonal testing under dust-free conditions. The results show that the flue gas flow rate had the greatest influence on the denitration efficiency of the catalyst. With an increase in flue gas flow rate, the denitration efficiency first increased and then decreased. When the flue gas flow rate was 0.3 m/s, the denitration efficiency reached a maximum. The denitration test was carried out using flue gas with a dust concentration of 15 g/m3. The results show that the denitration efficiency continued to decrease with the deposition of dust on the catalyst surface (from an initial value of 96.51 to 80.59% at the 140th min), and the pressure drop correspondingly increased from 100 to 630 Pa. Additional integration testing of dust removal and denitration showed that the average dust removal efficiency of the integrated device for dust removal and denitration using a dual-layer granular bed filter could reach 99.84%, and the average denitration efficiency could reach 95.07%.