赤泥用于烟气湿法脱硫技术研究及工业试验

Research and Industrial Test on Wet Flue Gas Desulfurization with Red Mud

针对含硫烟气严重污染大气环境及赤泥资源化利用的问题,采用赤泥湿法工艺处理含硫烟气。结果表明,赤泥处理含硫烟气的优化工艺条件为:液固比9∶1、烟气温度60℃、液气比8.0 L/m^(3)、脱硫液pH值5.6,此时烟气中SO_(2)浓度可从5 000 mg/m^(3)降到35 mg/m^(3)以下,满足超低排放标准。进行了75 t/h燃煤锅炉烟气脱硫工业试验,赤泥处理低硫烟气时,烟气中SO_(2)浓度从4 100 mg/m^(3)降到30 mg/m^(3)以下,脱除效率为99.68%;处理高硫烟气时,烟气中SO_(2)浓度从10 600 mg/m^(3)降到35 mg/m^(3)以下,脱除效率为99.89%。赤泥湿法脱硫与石灰石石膏法脱硫相比,相同的烟气量及SO_(2)指标情况下,采用赤泥作为湿法脱硫剂脱硫运行成本比石灰石石膏法低20.05%。

In order to solve problems including serious atmospheric pollution by sulfur⁃containing flue gas and utilization of red mud,sulfur⁃containing flue gas was treated by using a wet process with red mud.Under the following optimal process conditions,including liquid⁃solid ratio of 9∶1,flue gas at a temperature of 60℃,liquid⁃gas ratio of 8.0 L/m^(3),liquid with pH of 5.6 for desulfurization,the SO_(2) concentration in flue gas can be reduced from 5000 mg/m^(3) to less than 35 mg/m^(3),meeting a standard of ultra⁃low emissions.In an industrial experiment on desulfurization with red mud for the flue gas from a 75 t/h coal⁃fired boiler,the SO_(2) concentration in the low⁃sulfur flue gas was reduced from 4100 mg/m^(3) to less than 30 mg/m^(3),with removal efficiency up to 99.68%;while the SO_(2) concentration in the high⁃sulfur flue gas was reduced from 10600 mg/m^(3) to less than 35 mg/m^(3),with a removal efficiency up to 99.89%.Based on the comparison between this wet desulfurization with red mud and with limestone⁃gypsum flue gas desulfurization process,it is found that the wet flue gas desulfurization process with red mud as desulfurizer can have the operation cost reduced by 20.05%for the treatment of same volume of flue gas with the same SO_(2) concentration.