基于实测的电袋复合除尘器脱除多污染物效果

Removal of Multi-Pollutants from Coal-Fired Flue Gas by Electrostatic-Fabric Integrated Precipitator based on Field Tests

为了考察电袋复合除尘器脱除多污染物的能力,分别采用US EPA Method 30B方法、DL/T 998—2006《石灰石-石膏湿法烟气脱硫装置性能验收试验规范》、HJ/T 342—2007《水质硫酸盐的测定铬酸钡分光光度法(试行)》、GB/T 16157—1996《固定污染源排气中颗粒物测定与气态污染物采样方法》和国际标准化组织ISO23210-2009《Stationary Source Emissions-Determination of PM_(10)/PM_(2.5)Mass Concentration in Flue Gas-Measurement at Low Concentrations by Use of Impactors》对A、B两个燃煤电厂中循环流化床锅炉后的电袋复合除尘器脱除烟气中汞、SO_3、烟尘、PM_1、PM_(2.5)、PM_(10)六种污染物的效率进行测试试验.结果表明:电袋复合除尘器对烟尘、PM_(10)等颗粒态污染物捕集效率高达99%以上;两个电厂电袋复合除尘器中汞的质量平衡分别为112.05%、72.78%,在70%~130%的允许范围之内;B电厂中电袋复合除尘器进口处烟气中颗粒态汞占总汞含量的比例高达97%,电袋复合除尘器对颗粒态汞的捕集效率达99.93%,对气态汞的捕集效率达86.84%;由于滤袋表面烟尘粉饼具有一定的吸附作用,电袋复合除尘器对SO_3也有一定的捕集能力,A、B电厂电袋复合除尘器对SO_3的脱除效率分别达到90.04%和61.73%,脱除效率可能受到飞灰组分及其吸附能力的影响.研究显示,电袋复合除尘器对循环流化床锅炉烟气中的多污染物具有较高的协同捕集效率.

The installed capacity of electrostatic-fabric integrated precipitators （ EFIPs）, a new type of dust collector, in coal-fired power plants has exceeded 200 billion watts in China. However, there still lacks a better understanding of the removal performance on multiple pollutants of EFIPs. Therefore, the removal efficiencies for six kinds of pollutants in flue gas from the circulating fluidized bed boiler, including Hg, SO_3 , dust, PM_1 , PM_2.5 and PM_10 were tested in coal-fired power plants A and B, respectively. Mercury was tested by the 30B method of US EPA, S0_3 was tested by Performance Test Code for Wetlimestonegypsum Flue Gas Desulphurization （ DL/T 998-2006） for sampling and Water Quality-Determination of Sulfate-barium Chromate Spectrophotometry （ HJ/T 342-2007） for analysis, dust was tested by Determination of Particulates and Sampling Methods of Gaseous Pollutants Emitted from Exhaust Gas of Stationary Source （ GB/T 16157- 1996）, and fine particles were tested by Stationary Source Emissions-Determination of PM_10/PM_2.5 Mass Concentration in Flue Gas- Measurement at Low Concentrations by Use oflmpactors （ISO 23210-2009 ） to ensure the reliability of the data. The results showed that the particulate matter collection efficiency of dust, PM_10 and other particulate pollutants by EFIP were higher than 99%. Meanwhile, the mass balance of mercury across the EFIP of power plants A and B was 112. 05% and 72. 75% , respectively, within the acceptable ranges. The proportion of particulate-bound mercury in the flue gas at the inlet of EFIP in power plant B was as high as 97% , the collection efficiency of the particulate-bound mercury by EFIP was 99.93% , and the efficiency of gaseous mercury was 86.84%. The dust layer attached on the surface of the filter bag showed a certain adsorption to mercury, and SO_3 as well. The removal efficiencies of SO_3 by EFIP in power plants A and B were 90.04% and 61.73% , respectively. The removal efficiencies were also influenced by the composition of fly ash and the adsorption capacity of fly ash.