半干法SDA脱硫塔数值模拟与结构优化

Numerical simulation and structure optimization of semi-dry SDA desulfurization tower

现有SDA工艺无法满足超低排放要求,为提高脱硫效率,在原有SDA工艺基础上,开发更加高效的新型SDA脱硫处理工艺。进一步研究在脱硫塔塔体增设多点多介质混合物喷管对脱硫效率的影响,包含喷管位置(高度、管长)和钙硫比等参数的研究。通过数值模拟研究得出:在Y=1.4D布管时,多介质混合物在塔内分布最为均匀,贴壁最少,脱硫效率最高;在Y=1.4D布管时,管长在0.7D~D之间,脱硫效率从91.2%上升到95.2%;钙硫比在1.5~3时,脱硫效率增长幅度较大,从89.7%增长至97.2%。通过工业实验验证了喷射多介质混合物脱硫新工艺满足超低排放要求,脱硫效率在95%以上,出口SO_(2)浓度在35 mg/m^(3)以下。

The existing SDA generation process cannot meet the ultra-low emission requirements.In order to improve the desulfurization efficiency,a more efficient new SDA desulfurization process is developed on the basis of the original SDA process.The influence of adding multi-point and multi-medium mixture nozzles on desulfurization efficiency was further studied,including the location of nozzles(height,length)and the calcium-sulfur ratio.The results of numerical simulation show that,when Y=1.4D,the multi-medium mixture is most evenly distributed in the column,the least attached to the wall,and the highest desulfurization efficiency.When Y=1.4D,the desulfurization rate increased from 91.2%to 95.2%within the range of 0.7D~D.When the calcium-sulfur ratio is 1.5~3,the desulfurization efficiency increases greatly,from 89.7%to 97.2%.Through industrial experiments,it is verified that the new desulfurization process with injection of multi-medium mixture can meet the production requirements.The desulfurization rate is more than 95%,and the concentration of SO_(2) exported is less than 35 mg/m^(3).