Mechanism Study On Multi-Pollution Control Simultaneously During Coal Combustion And Direct Numerical Simulation Of Reaction Jets Flow

With the rapid development of Chinese economic, the Energy and Environmental problems come up to the surface. Coal combustion is the main energy source in China recently and in the near future. Emissions such as NO_x, SO₂ and mercury during coal combustion is extraordinary harmful to our atmosphere. So far, individual control of pollutions is not only larger investment, but also additional application expenses needed. In view of successful experience from the developed countries, it is significantly important for simultaneous removal of multi-pollutions.With an eye on WFGD technology application in large scale as a method to desulfurization control for the present, this paper focuses on the NO_x removal, and multi-pollution control such as SO₂, Hg, HCl, HF are also concerned simultaneously . On the basis of coal Reburning and SNCR reaction mechanism research and the situation of our country, the paper brings out a new method which utilized the combination of some technologies for the purpose of multi-pollution removal, high efficiency, low investment and low consumption. It is first mentioned that using ozone oxidization to simultaneous control flue gas multi-pollutions in one alkali absorption tower. The initial proposal for multi-pollution control using ozone technology on 300MW power plant was carried out. This combination method for multi-pollutions control in furnace an in the flue gas brought a new solution for the pollution control. Regarding to the impact of diffusion and mixing on the pollution control process, two-dimension reaction jets flow was simulated using detail reaction mechanisms in direct numerical simulation (DNS) method. The purpose of H₂/N₂ jet flame was to confirm our parallel reaction DNS program by comparison with Cabra's experiment. And then, the O₃/NO reaction jet was realized for pollution control process research. The vortex structure, shape, movement, combination and avulsion were also investigated.Firstly, the paper explored microcosmic method to analyze the fuel-NO_x emission process from Shenhua coal. Results show that the volatile-NO_x is the main component, which is 66.17～74.87% in the total NO_x. Higher temperature will accelerate the emission speed of volatile in coal particles, which will enhance the consumption of oxygen near the particle surface. This process will strengthen the fuel-rich condition at the moment of volatile combustion, which is believed benefit for low NO_x formation. In our experiment, the combustion condition at 1200℃ has the lowest amount of NO_x emission compared to 1100℃ and 1000℃. This paper first-adopts SRV to qualify the atmosphere of the volatile combustion moment. The traditional boiler design method at SRV=1.0～1.25 primary air...