PAHs Emissions Property And Its Catalytic Decompose Investigation During Combustion Process

Based on the project of trace organic emissions control during coal combustion process subsidized by special funds for Major State Basic Research Projects of China (G1999022211), this thesis develop the study of Polycyclic Aromatic Hydrocarbons (PAHs) emissions control during combustion process. There are four primary objectives of this work:The experimental results of the influence of combustion condition on PAHs emissions during coal combustion process on fluidized bed and experimental tube furnace are summarized. Combining the relevant research results of world, the low PAHs emissions combustion condition is put forward by the method of principal component analysis. The analytic results indicate that the main influence factor of PAHs emissions on fluidized bed is air flow, and the main influence factor of PAHs emissions on pulverized coal combustion boiler is the kind of coal, and the main influence factor of PAHs emissions on experimental tube furnace is content of volatile.The emission and decompose property of PAHs in flue gas of municipal domestic refuse incinerator and pulverized coal combustion boiler are simulated on experimental tube, furnace. The experimental results indicate that the PAHs in flue gas of municipal domestic r efuse i ncinerator will decomposed abundantly. The total emissions of 17 PAHs and the PAHs TEQ (toxicity equivalence quantity) emission are reduced linearly with the increase of oxygen content. And the PAHs in flue gas of pulverized coal combustion boiler indicate that the total emissions of 17 PAHs and the PAHs TEQ emission present four orders function with oxygen content.V2O5-WO3/T1O2 catalyst is prepared and analyzed with EDX and XRD. The analytical results indicate that the catalyst prepared method is reasonable. The catalytic decompose effect of anthracene by V2O5-WO3/TiO2 catalyst is investigated when reaction temperature, air flow and the concentration of anthracene changed. The experimental results indicate that the catalytic decompose efficiency of anthracene reduced linearly with reaction temperature and the concentration of anthracene increased. The space velocity property of Anthracene on V2O5-WO3/TiO2 catalyst is favourable. The catalytic decompose dynamical m odel is also set up based on the experimental results.The catalytic decompose property of PAHs in the flue gas of coal combustion and the flue gas mixture of coal and PCP on the V2O5-WO3/TiO2 catalyst with different ratio of tungsten to vanadium. These experiments can serve as research basis for catalyst optimization. The results show that three catalysts with d ifferent r atio of tungsten to vanadium can decompose the PAHs under 200C, and better effects can be reached with high ratio of V2O5. With lower temperature, the activities of three kinds of catalyst to decompose the low molecular weight PAHs became weaken, and totally been lost when the temperature was lower than 180C. The activity to decompose the low molecular weight PAHs and moderate molecular weight PAHs lost when the temperature was lower than 150C.