炼焦装煤烟气稀释采样过程中稀释比对PM_(2.5)测量的影响  

EFFECT OF DILUTION RATIO ON MEASUREMENT OF PM_(2.5)DURING DILUTION SAMPLING PROCESS OF COKING COAL CHARGING FLUE

作　　者：曹芮宁 李振 闫雨龙 彭林 韩东航 牛月圆 段小琳 徐寅杰 CAO Ruining;LI Zhen;YAN Yulong;PENG Lin;HAN Donghang;NIU Yueyuan;DUAN Xiaolin;XU Yinjie(MOE Key Laboratory of Resources and Environmental System Optimization,School of Environmental Science and Engineering,North China Electric Power University,Beijing 102206,China;Engineering Research Center of Clean and Low-carbon Technology for Intelligent Transportation,Ministry of Education,School of Environment,Beijing Jiaotong University,Beijing 100091,China;Changzhi Academy of Eco-Environmental Science(Changzhi Eco-Environmental Technology Service Center),Changzhi 046000,China)

机构地区：[1]华北电力大学环境科学与工程学院资源环境系统优化教育部重点实验室,北京102206 [2]北京交通大学环境学院智能交通绿色低碳技术教育部工程研究中心,北京100091 [3]长治市生态环境科学研究院(长治市生态环境技术服务中心),山西长治046000

出　　处：《环境工程》2023年第8期127-136,共10页Environmental Engineering

基　　金：国家重点研发计划项目(2019YFC0214200);国家自然科学基金项目(22106044,21976053);中央高校基本科研业务费专项资金(2021MS035)。

摘　　要：为探究炼焦装煤排放颗粒物稀释采样过程中,不同稀释比对测量PM_(2.5)粒径分布和碳质组分的影响,以管式炉热解煤炭来模拟炼焦装煤过程,通过建立稀释采样系统,设置低、中、高3个稀释比梯度,研究了PM_(2.5)的粒径分布、质量浓度、有机碳(OC)/元素碳(EC)和多环芳烃(PAHs)浓度的变化规律。结果显示:随着稀释比的增大,PM_(2.5)粒数浓度整体呈升高趋势,除尘后高稀释比下PM_(2.5)粒数浓度相对中、低稀释比分别增大了约3.7,1.3倍,除尘前高稀释比下PM_(2.5)粒数浓度相对中、低稀释比增大了约1.1倍;PM_(2.5)质量浓度及OC/EC整体随稀释比的增大呈减小趋势,较低稀释比升高到中等稀释比后,修正PM_(2.5)及OC/EC变化不显著,但高稀释比下,修正PM_(2.5)及OC/EC相比低稀释比时分别减小了约64.8%、45.1%;在不同稀释比下颗粒态PAHs的环数分布相对稳定,除尘后颗粒物中四环和五环芳烃的归一化占比较高,均在29.1%以上。稀释比升高增强了有机物的气粒转化,其在小粒径段上均相凝结增强,生成了更多超细颗粒物,PM_(2.5)总粒数浓度增加;继续升高稀释比,降低了体系中气态有机物浓度,其在大粒径段上的非均相凝结减弱,修正PM_(2.5)质量浓度降低。中等稀释比(41~52倍)下,气态有机物气粒转化相比低稀释比下更加充分,相比高稀释比,避免了烟气体系气粒相平衡破坏或有机物的过度凝结,因此建议采用中等稀释比采集分析炼焦装煤排放的PM_(2.5)。To investigate the effects of different dilution ratios on the particle size distribution and carbonaceous fraction of PM_(2.5)in the dilution sampling process of coking coal charging flue,the experiment of the coal coking process was carried out with a tube furnace.With low,medium,and high dilution ratios,PM_(2.5)size distribution,PM_(2.5)mass concentration,the ratio of organic carbon to elemental carbon(OC/EC)and polycyclic aromatic hydrocarbons(PAHs)concentration were determined under different dilution conditions.The result showed that the dilution ratio had a significant effect on ultrafine particles.As the dilution ratio increased,the particle number concentration showed an increasing trend,and the PM_(2.5)number concentration at the high dilution ratio increased by about 3.7 and 1.3 times,compared with the medium and low dilution ratios after particle filtration,respectively.In contrast,the concentration of PM_(2.5)with the high dilution ratio before particle filtration increased by 1.1 times approximately,compared to those at both the medium and low dilution ratios.As the dilution ratios increased,the corrected PM_(2.5)mass concentration and OC/EC ratio showed a decreasing trend.No significant changes in the corrected PM_(2.5)mass concentration and OC/EC ratio were observed when the dilution ratio increased from low level to medium level.At the high dilution level,the corrected PM_(2.5)mass concentration and OC/EC ratio decreased by about 64.8%and 45.1%,respectively,compared to those at low dilution ratios.The ring number distribution of PAHs was relatively stable at different dilution ratios.The normalized proportion of 4-and 5-ring aromatic hydrocarbons in PM_(2.5)was more than 29.1%.The dilution ratio increase promoted the gas-particle conversion of the organic matter,and the homogeneous condensation of gaseous organic matter on the small particle size range was enhanced.So that many ultrafine particles were generated and the total particle number concentration of PM_(2.5)drastically increased.A furthe

关 键 词：炼焦工业 细颗粒物(PM_(2.5)) 稀释采样 粒径分布 有机碳 多环芳烃 

分 类 号：X784[环境科学与工程—环境工程] X831