【摘要】 采用自设固定源PM_2.5稀释采集系统,对陕西省关中地区3个不同类型锅炉及钙法脱硫工艺的燃煤电厂PM_2.5开展了现场实测与样品化学源组分分析。结果表明,脱硫工艺对PM_2.5中爱根核模态的质量浓度影响不很显著,而对积聚模态的质量浓度影响较为显著（WFGD大于DSCD）;燃煤特性及锅炉类型对PM_2.5数浓度影响较大,特别是在小粒径范围（0. 08μm <D_p<0. 64μm（D50%））内影响更为明显。锅炉类型对PM_2.5中不同粒径段颗粒物的质量浓度/数浓度占比存在影响,相对循环流化床,煤粉炉在小粒径段颗粒物的质量浓度/数浓度占比更大;脱硫工艺对PM_2.5中不同粒径段颗粒物的质量浓度/数浓度占比存在影响,相对DSCD,WFGD在小粒径段颗粒物的质量浓度/数浓度占比更大;煤粉炉PM_2.5主要呈球形,循环流化床锅炉PM_2.5主要呈不规则形。SO₄^2-是各电厂PM_2.5中最丰富的离子,SO₄^2-占总离子质量浓度比重为50. 02%～65. 52%,Na⁺和Ca²⁺位于第2或第3位;各电厂主要检出无机元素是Si、Al、Ca、Na、Fe、Na等地壳元素。各电厂PM_2.5、PM₁₀、颗粒物的排放因子分别为0. 001～0. 028 kg/t、0. 002～0. 086 kg/t、0. 003～0. 236 kg/t;除尘设施组合越复杂,排放因子可能越小。更多还原

【Abstract】 The given paper intends to conduct a field experiment and chemical composition analysis of PM_2.5 from the 3 coal-burning power plants in different boiler types and calcium desulfurization processes in Guanzhong area,Shaanxi. It has done a research with the dilution and collection system of PM_2.5 in the stationary sources designed by our own research team. The investigation and experiment results demonstrate that the desulfurization process has no significant effect on the mass concentration of Aitken mode in the PM_2.5. Nevertheless,it has a significant effect on the mass concentration of the accumulation mode. On the other hand,the coal-burning features and the boiler types are poten-tially having great effect on the size intensity of PM_2.5,especially,in the small particle size range（ 0. 08 μm < D_p< 0. 64 μm（ D50%））. Hence,the boiler types may also have their own effects on the proportion of the mass/size intensity of the particle range of PM_2.5,as compared with the circulating fluidized bed.For,the mass/thickness concentration of the particles in the pulverized coal burning boilers in particle size range tends to account for the predominantly larger proportion whereas the desulfurization process has its own effect on the proportion of the mass/size thickness in the different thickness ranges of PM_2.5.And,so,as compared with DSCD,the mass/thickness concentration of the particles in WFGD in small particle size should account for a larger proportion. In addition,since the PM_2.5 produced from the pulverized coal burning boiler is spherical in shape with their circulating fluidized bed boiler being irregular,SO₄^2- should be the most abundant ions of PM_2.5 in such power plants,and,the ratio of SO₄^2- to the total ion concentration rates may range from 50. 02% to 65. 52%,with Na⁺and Ca²⁺being located at the second or third circle. If so,the main inorganic elements in the power plants should be Si,Al,Ca,Na,Fe,Na and the rest crustal elements. In such a situation,the emission factors of PM_2.5,PM₁₀ and the rest particles should be constituting 0. 001-0. 028 kg/t,0. 002-0. 086 kg/t,0. 003-0. 236 kg/t in all the respective power plants. Thus,the more complex the combination of the dust removal facilities,the less the emission factors are likely to be.更多还原