我国西南四省(区)大气煤基PAHs排放系统动力学分析

由于未来相当长时期内煤炭在我国的主体能源地位不会改变,全国许多地区均可能面临持续的大气煤基PAHs污染.为此,本文选取PAHs污染相对严重但缺乏足够关注的广西、四川、贵州与云南4个西南省份作为研究对象,基于煤基PAHs排放、能源消耗与经济发展之间的相互作用关系,利用系统动力学方法构建了一套综合评估模型,并将其应用于分析不同情景下西南四省(区)煤基PAHs排放的动态变化.结果表明,在维持情景下,未来10年煤基PAHs排放相对增长率的省份次序为:广西(44.54%)贵州(29.44%)云南(26.37%)四川(-2.19%).经过产业与能耗结构的调整,四川和云南在规划情景下的相对增长率分别比维持情景减少了27.17%和20.88%,这两个省的减排效果最大.同样的情况,贵州与广西仅分别减少了7.32%和5.52%,仍保持较快的增长趋势.要实现煤基PAHs的有效减排,各省份需实施有针对性的调控政策.云南应同时考虑工业源与生活源控制政策,四川应减少工业源排放量,广西和贵州应在进一步优化产业与能耗结构的基础上分别采取工业源和生活源控制政策.总体而言,系统动力学方法适用于分析非常规大气污染物的复杂动态变化,可为当地政府提供科学调控区域经济-能源结构-环境质量之间发展关系的政策参考.

System dynamics analysis of atmospheric coal-related polycyclic aromatic hydrocarbons emission in Southwest China

As the main energy status of coal in China will not change for a long period of time, many regions throughout the country may face persistent atmospheric coal-related polycyclic aromatic hydrocarbons (PAHs) pollution. In this study, four provinces, Guangxi, Sichuan, Guizhou and Yunnan, in Southwest China were chosen as the target areas due to the inadequate research concern for their relatively serious PAHs pollution. Based on the interrelationships among coal-related PAHs emission, energy consumption and economic development, a comprehensive assessment model was developed by using system dynamics (SD) method and applied to analyze the dynamic variations of coal-related PAHs emission for the four provinces under three designed scenarios. The results showed that, under maintaining scenario, the relative growth rates of coal-related PAHs emission for the four provinces were in the order of Guangxi (44.54%) > Guizhou (29.44%) > Yunnan (26.37%) > Sichuan (-2.19%). After the adjustment of industry structure and energy consumption structure, the relative growth rates for Sichuan and Yunnan under planning scenario were reduced 27.17% and 20.88%, respectively, compared with those under maintaining scenario, resulting in the maximum emission reduction effects among the four provinces. The relative growth rates for Guizhou and Guangxi under planning scenario were merely reduced 7.32% and 5.52%, respectively, so these two provinces still maintained a relatively fast increasing trend. To achieve the effective emission reduction of coal-related PAHs, the targeted regulation policies should be implemented for the four provinces. The control policies for both industrial and household sources should be considered for Yunnan. The emission from the industrial sources should be reduced in Sichuan. The control policies for industrial and household sources should be adopted for Guangxi and Guizhou, respectively, based on further optimization and upgradation of the industry and energy structure for these two provinces. In conclusion, the SD method is capable of comprehensively analyzing the dynamic variations of unconventional atmospheric pollutants, thus providing policy references for local governments to scientifically regulate the development relationships among regional economy, energy structure and environmental quality.