固定污染源废气中硝酸雾测定方法研究

通过国内外文献调研和硝酸雾采样方法比对实验研究，提出了固定污染源废气中的硝酸雾包括硝酸气体、硝酸液滴及颗粒物中的硝酸盐。建立了固定污染源废气中硝酸雾的分析方法：使用经1 mol/L Na₂CO₃溶液浸渍的石英滤膜捕集固定污染源废气中的硝酸雾，离子色谱法进行分析。实验结果表明：当采样体积为0.4 m³时，方法检出限为0.04 mg/m³;低、中、高浓度空白加标样品相对标准偏差均在9.2%以内，加标回收率为89.9%～117%。选取4种典型硝酸雾固定污染源废气进行实际样品采集与分析，硝酸雾质量浓度分别为1.62、1.86、1.63、19.8 mg/m³。对电子元件电镀车间固定污染源废气进行不同浓度的实际样品加标回收实验，加标回收率分别为86.0%和104%。

Study on Determination Method of Nitric Acid Mist in Exhaust Gas from Stationary Source

Through literature research at home and abroad,experimental study on comparison of sampling methods of nitric acid mist,it is proposed that nitric acid mist in the exhaust gas from stationary mainly exists in the form of nitric acid gas,nitric acid droplets and particulate nitrate.Establish a detection method of nitric acid mist in stationary source:collect the sample by the quartz filter membrane impregnated with 1 mol/L Na₂CO₃ solution and analysis it by ion chromatography.The study showed that the detection limit of the method is 0.04 mg/m³ when the sampling volume is 0.4 m³.The relative standard deviations of low,medium and high concentrations of blank spiked samples were within 9.2%,and the recoveries ranged from 89.9% to 117%.Actual samples from 4 kinds of typical stationary sources were collected and analyzed,the emission mass concentrations of nitric acid mist were 1.62,1.86,1.63,19.8 mg/m³ respectively.The recovery rates of the actual samples with different concentrations were tested for the pollutant gas from the electroplating pickling workshop,and the recovery rates were 86.0% and 104% respectively.