A series of CeO2 supported V2O5 catalysts with various loadings were prepared with different calcination temperatures by the incipient impregnation. The catalysts were evaluated for low temperature selective catalytic reduction (SCR) of NO with ammonia (NH3). The effects of O2 and SO2 on catalytic activity were also studied. The catalysts were characterized by specific surface areas (SBET) and X-ray diffraction (XRD) methods. The experimental results showed that NO conversion changed significantly with the different V2O5 loading and calcination temperature. With the V2O5 loading increasing from 0 to 10 wt%, NO conversion increased significantly, but decreased at higher loading. The optimum calcination temperature was 400°C. The best catalyst yielded above 80% NO conversion in the reaction temperature range of 160°C–300°C. The formation of CeVO4 on the surface of catalysts caused the decrease of redox ability.

The Hg0 removal ability of γ-Al2O3 impregnated with cerium dioxide (CeO2/γ-Al2O3) was tested in the experimental flue gas of N2 + O2 + NO + SO2 + H2O. Brunauer–Emmett–Teller (BET), X-ray diffractogram (XRD), and thermogravimetric (TG) analyses were used to characterize the samples. The effects of CeO2 loading values, reaction temperatures, reaction time, and individual flue gas components, including SO2, NO, O2, and H2O(g), on the Hg0 removal efficiency were investigated. The results show that the Hg0 removal efficiency of γ-Al2O3 can be greatly improved by CeO2 and, at a test temperature of 350 °C, the best suitable loaded mass percentage of CeO2 is 9%. In the temperature range from 150 to 350 °C, the Hg0 removal efficiency using CeO2/γ-Al2O3 increases with the increase of the temperature and then decreases above 350 °C, except virgin γ-Al2O3. In addition, the presence of O2 and NO have positive effects on the Hg0 removal efficiency, while the presence of SO2 and H2O inhibited it. Furthermore, prolonging the reaction time had a small negative effect on the Hg0 removal performance, indicating that the catalyst of CeO2/γ-Al2O3 possesses thermostability.

A novel wet-type flue gas desulphurization process were developed and tested in this study. The process used a PCF device as the absorber where SO2 was absorbed into slurry of reactive CaCO3. A model of external mass-transfer based on the two-film theory was proposed for estimation of the SO2 absorption in the PCF device, and the theoretical SO2 removal efficiency was compared with the experimental data. The results show that the SO2 absorption rate in the spray zone is controlled by a combination of gas- and liquid-film diffusions in the range of tested operating conditions. The increase of gas flow rate and droplet size and decrease of liquid−gas ratio all can lead to a decrease in the SO2 removal efficiency. Addition of Cl− to the slurry (25 g/L) decreases the SO2 removal efficiency from 83.87 to 70.75%. when comparing the results of prediction and experiment, the data show good agreement. With droplet size equal to 2500 μm, when gas flow rate and liquid−gas ratio are changed, the relative errors of SO2 removal efficiency between the predicted and experimental data are below 3.40 and 8.67%, respectively. It demonstrates that the model proposed in the present study is an effective model to evaluate and predict the desulphurization performance of the novel type PCF device. Moreover, the theoretical model can be extended to apply in other wet FGD technologies.

Aiming at the characteristics of carbon black, a new method of controlling the black smoke from the industrial coal-burning ceramic kilns by wetting was brought forward. The carbon black in the flue of coal-burning ceramic kiln was collected for the experiments, and its physical and chemical properties were studied in detail. In order to change the sedimentation and wettability state of the carbon black, the complex solution of the coagulant and surfactant was applied. After a series of orthogonal experiments, the complex solutions with better effects were chosen. Then, the sedimentation percentage of carbon black treated by the selected complex solutions was measured. The optimized complex solutions included Na2SO4 (100 mmol/L), sodium dodecyl benzenesulfonate (SDBS) (1.2 mmol/L) and polyacrylamide (PAM) (40 mg/L). After carbon black was absorbed, the complex solutions were clear and colorless. The complex solutions can be recycled, and the sedimentation percentage of carbon black is 94%.