摘要
烟气中三氧化硫(SO_(3))是固定源可凝结颗粒物的主要气态前体物之一,排入大气环境后可形成“蓝烟”,具有较强的腐蚀性和环境毒性。目前监测烟气中SO_(3)的方法有多种,测量结果差异较大、准确性较难评判,需要对SO_(3)监测设备进行定期标定。但由于SO_(3)反应活性高、难以稳定保存,导致缺少标气,这大大限制了SO_(3)测量的准确性。研制了基于催化氧化SO_(2)生成SO_(3)的便携式标气发生装置,并对其SO_(3)的产率、稳定性及其影响因素进行了评测。结果表明:在填装600 mg钒催化剂(40~60目),持续通入0.1 L/min、1000 ppm(μmol/mol)的SO_(2)气体,催化温度430℃的条件下,SO_(2)转化效率为98.5%。用洁净零空气按一定比例对高浓度SO_(3)气体进行稀释混合,可线性输出浓度范围10~1000 ppm的SO_(3)标气,用于SO_(3)监测设备的标定和质控。
SO_(3) is one of the most important precursors of condensable particulate matter,and easily transferred into blue flue gas after emission,which causes adverse effects on the atmospheric environment.SO_(3) is also corrosive and hazardous gas.It is necessary to measure and monitor its concentration in flue gas.At present,the results and accuracy for methods monitoring SO_(3) in flue gas are difficult to judge and equipments need to be calibrated regularly.However,SO_(3) is reactive and difficult to store in the tank and must be generated on-site.The lack of ready-made standard gas is the major limiting factor for accurate measurement and monitoring of SO_(3).In this paper,a SO_(3) generator was developed based on the principle of catalytic oxidation.Its performance,stability,and influencing factors were evaluated.The conversion ratio was stable at 98.5%on the condition that injecting 1000 ppm(μmol/mol)SO_(2) at a flow rate of 0.1 L/min,loading 600 mg vanadium catalysts(40~60 mesi),and setting the conversion temperature at 430℃.By diluting the highly-concentrated SO_(3) with clean air of different flow rates,the generator linearly outputs SO_(3) standard gas in the range of 10 ppm to 1000 ppm,which can be used for calibration of measurement and monitoring of SO_(3).
作者
邓建国
王东滨
蒋靖坤
DENG Jianguo;WANG Dongbin;JIANG Jingkun(School of Environment,Tsinghua University,Beijing 100084,China;State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex,Beijing 100084,China)
出处
《环境工程》
CAS
CSCD
2024年第9期255-260,共6页
Environmental Engineering
基金
国家重点研发计划“固定污染源超低排放高精度监测与质控技术”(2022YFC3700502)。
关键词
固定源
三氧化硫
标气发生装置
标定
可凝结颗粒物
stationary source
SO_(3)
standard gas generator
calibration
condensable particulate matter
