钙基半干法燃煤烟气脱硫技术的影响因素

半干法烟气脱硫技术因具有耗水量少、产物易处理等特点而备受关注。基于固定床反应器研究了反应温度、脱硫剂Ca(OH)₂颗粒粒径、反应空速及烟气中水蒸气体积分数对Ca(OH)₂脱硫性能的影响。结果表明，Ca(OH)₂颗粒粒径的减小、反应空速的降低、烟气中水蒸气体积分数的提高及低反应温度等因素，有利于SO₂的脱除、Ca(OH)₂利用率的提高及Ca/S的降低。当Ca(OH)₂颗粒的平均粒径为0.58 mm、反应空速为2 500 h⁻¹、模拟烟气中水蒸气体积分数为12%、反应温度为55 ℃时，可获得最佳脱硫效果。在SO₂穿透浓度35 mg·Nm⁻³下，Ca(OH)₂的利用率可达到71.3%，此时Ca/S为1.4。在上述条件下，SO₂达到穿透浓度时，通过实施脉冲增湿可使穿透时间延长、Ca(OH)₂利用率进一步提升至75.7%。本研究结果可为半干法脱硫工艺的改进提供参考。

Influencing factors of coal-fired flue gas desulfurization by calcium-based semi-dry method

Semi-dry flue gas desulfurization has attracted extensive attention because of its characteristics of low water consumption and easy treatment of products. The effects of reaction temperature, particle size of desulfurizer Ca(OH)2, reaction space velocity, and volume fraction of water vapor in flue gas on the desulfurization performance of Ca(OH)2 were researched in a fixed bed reactor. Results showed that the reduction of Ca(OH)2 particle size, the decrease of space velocity, the increase of water vapor volume fraction in flue gas and the low reaction temperature were conducive to the removal of SO2, Ca(OH)2 utilization and the reduction of Ca/S. The best desulfurization performance could be achieved when the average particle size of Ca(OH)2 was 0.58 mm, the space velocity was 2 500 h−1, the volume fraction of water vapor in the simulated flue gas was 12% and the reaction temperature was 55 ℃. When the SO2 penetration concentration reached 35 mg·Nm−3, the utilization rate of Ca(OH)2 was 71.3%, and the Ca/S was 1.4. Under the above conditions, when the content of SO2 reached penetration concentration, penetration time can be prolonged and Ca(OH)2 utilization rate can be further increased to 75.7% by implementing pulse humidification. The results of this study can provide reference for the improvement of semi-dry desulfurization process improvement.