收稿日期:2022-08-19加热炉烟气中甲烷对二氧化硫浓度检测的干扰吕华(大连西太平洋石油化工有限公司,辽宁大连116600)摘要:二氧化硫是重点管控的废气污染物之一。在使用非分散红外吸收法进行烟气中二氧化硫检测的过程中,发现在燃料气硫含量、过剩空气系数均不高的情况下,烟气中二氧化硫浓度往往会异常升高。通过大量数据分析、离线检测比对以及实验,确认了甲烷干扰二氧化硫浓度检测的问题。1×10-6甲烷对SO2的贡献值在0.14mg/m3左右。二氧化硫的最强吸收波长7.3μm和甲烷在强吸收波段7.2~8.3μm间有很明显的重叠,造成干扰。应考虑如何有效降低甲烷含量或采取有效手段消除、减少甲烷的干扰。关键词:非分散红外吸收法;烟气;二氧化硫;甲烷;干扰中图分类号:X830.7文献标志码:A文章编号:1007-7804(2023)01-0024-05doi:10.3969/j.issn.1007-7804.2023.01.008InterferenceofMethaneinHeatingFurnaceFlueGasonDetectionofSulfurDioxideConcentrationLÜHua(DalianWestPacificPetrochemicalCo.,Ltd.,Dalian116600,China)Abstract:Sulfurdioxideisoneofthekeyexhaustgaspollutantsundercontrol.Intheprocessofusingnon-dispersiveinfra-redabsorptionmethodtodetectsulfurdioxideinfluegas,itwasfoundthattheconcentrationofsulfurdioxideinfluegasof-tenincreasedabnormallywhenthesulfurcontentoffuelgasandtheexcessaircoefficientwerenothigh.Throughalargea-mountofdataanalysis,off-linedetectioncomparisonandexperiments,theproblemofmethaneinterferingwiththedetectionofsulfurdioxideconcentrationwasconfirmed.Thecontributionof1×10-6methanetoSO2isabout0.14mg/m3.Thestrongestabsorptionwavelengthofsulfurdioxideat7.3μmandthestrongabsorptionwavelengthofmethanebetween7.2~8.3μmhaveobviousoverlap,causinginterference.Howtoeffectivelyreducethemethanecontentortakeeffectivemeas-urestoeliminateandreducetheinterferenceofmethaneshouldbeconsidered.Keywords:non-dispersiveinfraredabsorptionmethod;fluegas;sulfurdioxide;methane;interference1前言燃料燃烧产生的烟气是大气污染物的一个主要来源,而二氧化硫是污染物之一,也是我国重点管控的废气污染物。二氧化硫会刺激人的呼吸道,危害人体健康。二氧化硫与空气中的水结合能够形成酸性物质,引发酸雨,进入到土壤和水源中,造成二次污染危...