Experiment And Numerical Simulation Study On Black Smoke Prevention In Canopy Dust Catcher

In China the fuel of most industrial ceramic kilns depends on coal. Duringthe burning of the industrial coal-burning ceramic kilns, much black smoke created.It bring serious grave air-pollution. In this paper, the purification efficiency of black smoke released by the smoke-producer plant (Patent No.:CN200420069314.9) was studied using a patent equipment canopy dust catcher. The effects of inlet dust loading, inlet velocity, liquid-gas ratio and surfactant additives on purification efficiency of black smoke and voltagedrop were also discussed. Based on above experimental results of this study, the different particles concentration distribution of black smoke in a canopy dust catcher was numerically simulated using FLUENT software. The reliability compliance test of dynamic model was carried out by comparison between the results of experiment and simulation. It provided the basis of complete data model for evaluating performance of the canopy dust catcher.Physical and chemical properties of the fly ash were tested firstly, and the Rosin-Rammler distribution of the fly ash and the leak rate of the device were tested through experiments. The purification of black smoke from coal-burning ceramic kilns were carried out with an canopy dust catcher. The effects of the inlet dust concentration, inlet flue gas velocity, liquid-gas ratio and absorption liquids on removing efficiency of black carbon were studied using different absorption liquids. The results showed that when u=12 m/s and L/G=0.2 L/m3, the removing efficiencies of black carbon increased at first then decreased with the raising of inlet dust concentration.7 g/m3 of inlet dust concentration was suitable to the purification of black carbon, at which the removing efficiencies of black carbon was 95.74%. When L/G=0.2 L/m3, Cin=2 g/m3, the removing efficiencies of black carbon and voltagedrop increased with the. raising of inlet flue gas velocity. When u=12 m/s, L/G=0.2 L/m3, Cin=2 g/m3, four absorption liquids were prepared by surfactants of CTAB, SDBS, AEO-9 and OP-10, among which AEO-9 had slight higher BC purifying property. The removing efficiency of black carbon was about 99.5% when its concentration was 0.06 mmol/L.The different particles concentration distribution of black smoke in a canopy dust catcher was numerically simulated with selecting RSM and DPM as gas phase model and particle phase model respectively. The effects of particle diameter (0.24-11μm), inlet dust loading (1-7 g/m3) and inlet velocity (10-16 m/s) on the particle concentration distribution were calculated. The results showed that particles concentration of black smoke in a canopy dust catcher was radially distributed into low-concentration in the middle areas and high-concentration near the wall. In the same radial cross section, particles concentration increased with enhancing inlet dust loading, and decreased with increasing particle diameter and inlet velocity. The canopy dust catcher could distribute the particles more evenly, and effectively decrease the concentration of submicron particles like black smoke.By comparison between the results of experiment and simulation, it found that the voltagedrop within canopy dust catcher increased with the raising of inlet velocity and inlet dust loading. Both of the results were in good agreement with less than 6% of the error. Similarly the dedusting efficiency of black smoke in canopy dust catcher increased with the raising of inlet velocity and inlet dust loading. The values of dedusting efficiency obtained from the simulation results were in the range of 69-74%, which were in good agreement with the experimental results with less than 10% of the error. The experimental data verified the results of the simulation, which suggested numerical simulation was an effective method for predicting and evaluating the performance of a new installation.