广西典型行业VOCs排放源成分谱特征

Spectral characteristics of VOCs emission sources from typical industries in Guangxi

挥发性有机物(VOCs)作为臭氧生成的重要前体物,摸清其排放源成分谱特征,是破解臭氧污染防治难题的关键所在.当前,广西臭氧污染日益凸显,然而VOCs排放底数仍模糊不清.针对此问题,本研究对广西包装印刷、家具制造、汽车维修、岗石制造、人造板制造等5个典型行业VOCs排放进行采样,分析115种VOCs组分,探究其VOCs排放浓度水平、源成分谱特征及臭氧生成潜势.结果表明,包装印刷行业VOCs的浓度相对最高(12.98 mg·m^(−3)),是其余4个行业的2—86倍,其次分别为家具制造(5.72 mg·m^(−3))、汽车维修(1.34 mg·m^(−3))、岗石制造(0.84 mg·m^(−3))、人造板制造(0.15 mg·m^(−3))行业,其中,包装印刷行业排放以烷烃(55.37%)为主,其次是OVOCs(27.51%);家具制造行业以OVOCs(50.98%)排放为主,其次是芳香烃(31.05%);汽车维修行业以芳香烃(32.25%)为主,其次是OVOCs(23.76%);岗石制造行业组成以烷烃(42.43%)排放为主,其次是芳香烃(23.76%);人造板制造行业以OVOCs(52.05%)排放为主,其次是芳香烃(14.32%).臭氧生成潜势计算结果显示,臭氧生成潜势大小依次为家具制造(22.62 mg·m^(−3))>包装印刷(17.24 mg·m^(−3))>汽车维修(4.29 mg·m^(−3))>岗石制造(1.44 mg·m^(−3))>人造板制造(0.50 mg·m^(−3))行业,5个行业中对臭氧生成潜势贡献最大的关键物种依次分别为己醛(44.21%)、2-甲基己烷(9.76%)、间/对-二甲苯(24.61%)、苯乙烯(29.27%)、乙醛(23.86%).针对家具制造、汽车维修、岗石制造、人造板制造行业的VOCs治理及其引起的臭氧污染防控应重点关注臭氧生成潜势贡献率大的关键VOCs物种.

Volatile organic compounds(VOCs)are important precursors for ozone generation,and characterising the compositional profile of their emission sources is the key to solving the problem of ozone pollution prevention.Currently,ozone pollution in Guangxi is becoming more and more prominent,but the emission of VOCs is still ambiguous.In order to address this problem,this study sampled VOCs emissions from five typical industries in Guangxi,namely packaging and printing,furniture manufacturing,automobile maintenance,granite manufacturing,and man-made board manufacturing,and analysed 115 VOCs components to investigate their VOCs emission concentration levels,source spectral characteristics,and Ozone Formation Potential(OFP).The results showed that the packaging and printing industry had the relatively highest concentration of VOCs(12.98 mg·m^(3)),which was 2—86 times higher than that of the remaining four industries,followed by furniture manufacturing(5.72 mg·m^(−3)),automotive servicing(1.34 mg·m^(−3)),granite manufacturing(0.84 mg·m^(−3)),and wood-based panel manufacturing(0.15 mg·m^(−3))industries,respectively.Among them,emissions from the packaging and printing industry were dominated by alkanes(55.37%),followed by oxygenated OVOCs(27.51%);emissions from the furniture manufacturing industry were dominated by OVOCs(50.98%),followed by aromatic hydrocarbons(31.05%);the automotive repair industry was dominated by aromatic hydrocarbons(32.25%),followed by OVOCs(23.76%);the composition of the granite manufacturing sector is dominated by alkanes(42.43%),followed by aromatic hydrocarbons(23.76%);and the wood-based panel manufacturing sector is dominated by OVOCs(52.05%),followed by aromatic hydrocarbons(14.32%).The results of OFP calculations show that the size of the OFP is in the order of furniture manufacturing(22.62 mg·m^(−3))>packaging and printing(17.24 mg·m^(−3))>automotive servicing(4.29 mg·m^(−3))>granite manufacturing(1.44 mg·m^(−3))>wood-based panel manufacturing(0.50 mg·m^(−3))industries,and the key species that make the largest contribution to the OFP in the five industries are,in order of magnitude,hexanal(44.0%),and aromatic hydrocarbons(23.76%).The key species contributing most to the ozone generation potential in the five sectors were hexanal(44.21%),2-methylhexane(9.76%),m/p-xylene(24.61%),styrene(29.27%),and acetaldehyde(23.86%),in that order,respectively.VOCs management for furniture manufacturing,automotive repair,granite manufacturing,and artificial board manufacturing industries and the prevention and control of ozone pollution caused by them should focus on high contribution rate key VOCs species.