Mechanisms Study Of Simultaneously Control Of SO₂ And NO_x Emissions With Organic Calcium

The combustion of coal generate of SO₂ and NO_X emissions, which pollute entironment badly. It is significantly important for Simultaneous reduction of NO_X and SO₂ emissions. In this article,the mechanism of pollutions control with organic calcium was discussed in detail with large amounts of theory analysis and experimentl test.Organic gas released during calcinations of organic calcium and the calculation of thermodynamic equilibrium found that the pyrolysis productions of organic gas were reducing gas such as CH₄,CO,H₂. Organic calcium developed a high porous cenospheric structure during its calcinations at high temperature. The surface area of the particle, measured by N₂ physisorption, was more biger than common calcium. As the organic gas released more first than volatile during combustion of coal, Organic calcium promote the ignition property of coal , improved whole combustion characteristics. Calcium magnesium acetate was the best additive as for the combustion-supporting character.Sulphur combined with Fe,Ca into FeS and CaS during initial period of combustion. CaS was the chief form after calcium addition . The change of SO₂ emission could be explained by the formation and oxidation of CaS at different period . Calculation of thermodynamic equilibrium forecasted the distribution of sulphur during combustion and it contribute the difference in distribution of species contained sulphur to atmosphere. The oxidation mechanism of CaS could be explained by Parallelism between the oxidation reaction of calcium sulphide and that of cailcium sulphite. Temperature,Concentraton of oxygen and diffusion resistance of product layer were dominant factors during the oxidation of CaS. The conversion of CaS to CaSO₄ during combustion with Char was greater than that of thermogravimetric experiment.Common calcium had weakly catalytic effect on the production and reduction of NO, which was proved by experiments in fixed-bed .However, organic calcium could reduce NO effectively by organic gas . NO control was best performed in poor oxygen. As for calcium magnesium acetate, the reduction efficency of NO increased with increasing temperarue, but for Calcium acetate the best reduction efficency of NO was achieved at 1150℃.Experiments were carried out to investigate the mechanism of simultaneous...