超低排放机组双塔双循环脱硫系统能耗物耗特性分析

Analysis of Energy and Material Consumption Characteristics of Double Tower Double Cycle Desulfurization System for Ultra Low Emission Unit

为系统分析双塔双循环脱硫系统能耗物耗特性,通过对53台双塔双循环脱硫系统电耗、水耗和石灰石耗量情况进行测试,研究入口SO_(2)浓度、液气比、pH值以及Ca/S比对单位质量SO_(2)脱除能耗物耗特性的影响。结果表明,双塔双循环脱硫系统SO_(2)脱除成本中脱除能耗成本占整体脱除成本的55%~80%,而脱除能耗中循环浆液泵电耗占总能耗的50%~70%,一二级吸收塔的SO_(2)单位脱除能耗均随入口SO_(2)浓度的增高而降低,二级吸收塔的SO_(2)单位脱除能耗远大于一级吸收塔,一二级吸收塔内SO_(2)单位脱除能耗均随pH值的升高而先降后增。因此,为降低双塔双循环脱硫系统单位质量SO_(2)脱除能耗物耗水平,一级吸收塔入口SO_(2)质量浓度应控制在4000~6000 mg/m^(3),浆液pH值应控制在5.2左右;二级吸收塔入口SO_(2)质量浓度应控制在1200 mg/m^(3),浆液pH值应控制在6.0左右。

In order to systematically analyze the energy and material consumption characteristics of double tower double cycle desulfurization system,testing the power consumption,water consumption and limestone consumption at the exit of double tower double cycle desulfurization systems in 53 ultra-low emission units.And study the effects of inlet SO_(2)concentration,liquid gas ratio,pH value and Ca/S ratio on the energy and material consumption characteristics of unit mass SO_(2)removal.The measurement results indicate that the the energy consumption of SO_(2)removal accounts for 55%~80%of the total removal cost,while the power consumption of circulating slurry pump accounts for 50%~70%of the total energy consumption.The energy consumption per unit of SO_(2)removal in primary and secondary absorption tower decreases with the increase of inlet SO_(2)concentration,and the energy consumption per unit of SO_(2)removal in secondary absorption tower is much higher than that in primary absorption tower,The energy consumption per unit of SO_(2)removal in the first and second stage absorption towers decreased first and then increased with the increase of pH value.Which shows that in order to reduce the energy and material consumption per unit mass of SO_(2)in the double tower double cycle desulfurization system,the SO_(2)concentration at the inlet of the primary absorption tower should be controlled at 4000~6000 mg/m~3,and the slurry pH value should be controlled at about 5.2;The concentration of SO_(2)at the inlet of secondary absorption tower should be controlled at 1200 mg/m~3,and the pH value of slurry should be controlled at about 6.0.