西安市人为源一次PM_(2.5)排放清单及减排潜力研究

Inventory and Reduction Potential of Anthropogenic PM_(2.5) Emission in Xi'an City

颗粒物是影响西安市环境空气质量的主要因子.结合《西安统计年鉴2015》《2014年环境统计数据》和现场调查等确定了西安市各类PM_(2.5)排放源的活动水平数据,采用物料衡算法和排放因子法测算了西安市2014年大气中PM_(2.5)的年排放总量,并从行业和区域角度详细分析了PM_(2.5)的排放贡献率.在此基础上,以2014年为基准年,依据西安市地方政策和各行业最新排放标准,对PM_(2.5)的减排潜力进行了预测.结果表明:2014年西安市人为源一次PM_(2.5)排放总量为33 660. 1 t,其中,固定燃烧源、工艺过程源、移动源、生物质燃烧源、扬尘源和餐饮源的贡献率分别为27. 6%、23. 5%、6. 8%、10. 7%、31. 1%和0. 3%.道路扬尘、窑炉和发电为西安市PM_(2.5)的重点排放行业,其PM_(2.5)排放量分别占排放总量的21. 4%、20. 3%和11. 0%.各区县中,鄠邑区、灞桥区和未央区的PM_(2.5)排放量较高,其贡献率分别为15. 7%、13. 7%和12. 7%;新城区PM_(2.5)排放量最小,为297. 8 t/a. 2014年西安市PM_(2.5)平均排放强度为2. 07 t/km2,其中,碑林区排放强度(16. 80 t/km2)最大,高陵区(0. 48 t/km2)最小.按照《西安市2017年"铁腕治霾保卫蓝天"工作实施方案》等新政策的规定,预测在新的排放标准下西安市PM_(2.5)排放量将比2014年削减63. 7%.研究显示,固定燃烧源、工艺过程源和生物质燃烧源有较大的减排潜力.

Particulate matter has been considered as the primary factor that significantly affected the air quality in Xi’an City. The activity data of different anthropogenic sources of fine particles(PM2.5) in Xi’an City was obtained from the statistical yearbook,environmental statistics data,and field investigation. The total annual emissions of fine particulate matters in Xi’an City(2014),as well as the emission weight distribution by diverse industries and regions,were evaluated by using mass balance calculation and emission factor method. In addition,the reduction potential of fine particulate matter emission was further predicted by selecting 2014 as the base year coupled with the local policies of Xi’an City,Shaanxi Province,and the latest emission standards of those industries. The results showed that the primary fine particulate matters emitted from anthropogenic sources in Xi’an City attained 33,660. 1 t which consisted of fixed combustion sources,technological process sources,mobile sources,biomass combustion sources,dust sources and catering industry with the weight distribution of 27. 6%,23. 5%,6. 8%,10. 7%,31. 1% and 0. 3%,respectively,in 2014. Road dust,industrial kilns and thermal power generation were considered as the dominant emission sources,accounting for 21. 4%,20. 3% and 11. 0% of the total emission,respectively. Regionally,the emissions from the Huyi District,Baqiao District and Weiyang District,with the distribution of 15. 7%,13. 7% and 12. 7%,respectively,were significantly higher than other districts. The New-urban district distributed the lowest emissions(297. 8 t/a). The results also demonstrated that the average emission intensity of fine particulate matters in Xi’an City was 2. 07 t/km2;the Beilin District accounted for the maximum emission(16. 80 t/km2),and the Gaoling District was the lowest district(0. 48 t/km2).Under the guidance of those new policies such as the Iron Fist to Control Haze and Protect Blue Sky,it is predictable that the emission reduction of fine particulate matters would attain 63. 7% compared with 2014 in Xi’ an City. The research shows that fixing combustion sources,technological process sources,and biomass combustion sources has potential to reduce fine particulate matter emission.