南京市化工行业非甲烷挥发性有机物排放清单研究

Study on emission inventory of non-methane volatile organic compounds for chemical industry in Nanjing

为详细评估城市尺度化工行业非甲烷挥发性有机物(NMVOC)的排放特征,本研究采用排放因子法建立了基于详细企业调查信息的南京市化工行业NMVOC排放清单,利用臭氧生成潜势(ozone formation potential,OFP)分析挥发性有机物(volatile organic compowds,VOC)排放的大气氧化活性,使用蒙特卡洛方法计算排放清单的不确定性。同时,将本研究结果与基于公开发表统计资料的排放计算结果进行了对比分析。研究结果表明,2011年南京市化工行业NMVOC排放量约为11.2万t,其中石油炼制贡献了化工行业总量的51.5%,基础化工原料、合成化工、精细化工、炼焦、其他化工贡献依次为13.3%、12.0%、11.4%、8.0%、3.8%。烯烃是OFP值最大的一类组分,对OFP贡献超过58%。2011年南京市化工行业NMVOC排放的不确定性用95%置信区间表示为(-74%,+267%)。研究发现,基于统计资料的方法遗漏了基础化学原料、合成化工中的部分排放源,导致对化工行业NMVOC排放存在约18.8%的低估。根据人口分布NMVOC排放进行空间分配,得到的结果未能较好反映重点排放源地理位置的影响。上述对比证实,在城市尺度进行详细排放源调查对改善排放清单具有重要作用。

To deeply analyze the emission characteristics of non-methane volatile organic compounds （NMVOC）from chemical in-dustry in typical city,an emission inventory of chemical industry NMVOC in Nanjing was developed using the emission factor method,based on detailed enterprise information from plant-by-plant onsite survey.The ozone formation potentials （OFPs）were calculated to assess the roles of NMVOC emissions in atmospheric oxidation.The uncertainty of this emission inventory was eval-uated by using the Monte Carlo method.The plant-based emission inventory was compared with that based on energy and indus-trial statistics.The NMVOC emissions were estimated at 112 000 metric tons for chemical industry in Nanjing at 2011.Oil refin-ery,basic chemical material manufacturing,synthetic chemical industry,fine chemical industry,coke making and other chemical industry contributed 51.5%,13.3%,12.0%,11.4%,8.0%,and 3.8%,respectively.The alkenes contributed more than 58% to the total OFP.The uncertainty of this emission inventory was estimate to be （-74%,＋267%）,in a form of 95% con-fidence interval.It was found that the VOC emissions based on statistics were underestimated by 18.8% because of the omission of some emission sources in basic chemical material manufacturing and synthetic chemical industry.Besides,the spatial allocation of emissions according to population density failed to capture the emissions from the key emission sources.The comparisons be-tween the two inventories demonstrated the importance of conducting detailed survey on improvement of emission inventory at city scale.