Zhang Yanxu, Dou Han, Chang Biao, Wei Zhicheng, Qiu Weixun, Liu Shuzhen, Liu Wenxin, Tao Shu
Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, China.
Ann N Y Acad Sci. 2008 Oct;1140:218-27. doi: 10.1196/annals.1454.006.
The emission factors for indoor straw combustion are a major data gap for estimating the polycyclic aromatic hydrocarbon (PAH) emissions in China. The emission factors for open-fire straw burning were borrowed from our previous study and a rough estimate was developed. As one of the most important emission sources in China, the emission factors for indoor straw combustion needed to be determined and revised accurately. In this study, a representative straw in rural China was collected and burned in similar conditions with those used by countryside families. The smoke produced was sampled and the PAH concentrations were analyzed by gas chromatography-mass selective detection (GC-MSD), and much higher emission factors were found. Based on the newly measured emission factors, the emission amount from indoor straw combustion was updated. In addition, recently published emission factors were compiled in a comprehensive database and some new sources were included. Additionally, the emission inventory was extended to cover the period from 1950 to 2005 and upgraded to a scale resolution of one kilometer. In the updated inventory, the total quantity of 16 PAHs emitted from China was 116,000 tons in 2003, with indoor straw and firewood combustions as the most important sources. Although vehicular emission contributed a relatively small percentage of the total emission, it was still one of the major sources in the urban areas of China. The total PAH emission increased continuously for four decades, starting from 1950, but fluctuated since 1990 due to variations in coke production.
室内秸秆燃烧的排放因子是估算中国多环芳烃（PAH）排放量时的一个主要数据缺口。明火秸秆燃烧的排放因子借鉴了我们之前的研究并进行了粗略估算。作为中国最重要的排放源之一，室内秸秆燃烧的排放因子需要准确测定和修订。在本研究中，采集了中国农村具有代表性的秸秆，并在与农村家庭使用的类似条件下进行燃烧。对产生的烟雾进行采样，并通过气相色谱 - 质量选择性检测（GC - MSD）分析多环芳烃浓度，发现了高得多的排放因子。基于新测量的排放因子，更新了室内秸秆燃烧的排放量。此外，将最近公布的排放因子汇编成一个综合数据库，并纳入了一些新的排放源。此外，排放清单的时间范围扩展至1950年至2005年，并升级到1公里的空间分辨率。在更新后的清单中，2003年中国排放的16种多环芳烃总量为11.6万吨，其中室内秸秆和柴火燃烧是最重要的排放源。尽管车辆排放占总排放量的比例相对较小，但仍是中国城市地区的主要排放源之一。自1950年起四十年来多环芳烃总排放量持续增加，但自1990年起由于焦炭产量的变化而出现波动。
