水泥企业不同固定源PM2.5排放特性

为获得水泥企业固定源颗粒物排放特性，采用自设固定源PM_2.5稀释采集系统对陕西省关中地区某水泥企业固定源中的细颗粒物开展了现场实测工作.结果表明:窑头主要排放粒径较小的颗粒物，其粒径分布特征与燃烧气态产物冷凝、碰并、凝聚等机制相关；窑尾、煤磨、破碎、水泥磨主要排放粒径较大的颗粒物，其粒径分布特征与原料、燃料及熟料的破碎、粉磨等物理性质相关；考虑废气标干流量情况下，固定源PM_2.5控制重点依次为窑头、煤磨、窑尾、水泥磨、破碎；窑头在爱根核模态和积聚模态的颗粒物浓度整体水平明显高于窑尾、煤磨、破碎（最高值间约相差3倍左右至1个数量级）；窑头、窑尾、煤磨、破碎浓度分布的共同特征是PM₁₀粒径分布谱中大于0.1 μm的各层级颗粒物质量大多较高且各层级间质量变化较为剧烈.窑头在爱根核模态和积聚模态的颗粒物数浓度整体水平明显高于窑尾、煤磨、破碎（最高值间约相差1~2个数量级）；窑头、窑尾、煤磨、破碎数浓度分布的共同特征是PM₁₀粒径分布谱中粗粒子模态数量均很小.窑尾、窑头、煤磨、破碎、水泥磨排放因子分别为0.156 g/t（以熟料计）、3.914 g/t（以熟料计）、1.538 g/t（以煤计）、0.016 g/t（以石料计）、0.056 g/t（以水泥计），PM_2.5排放总量分别为207.48、5 205.62、286.38、28.73、131.50 t，固定源PM_2.5排放总量为5 859.7 t.研究显示，水泥企业不同固定源颗粒物排放特性相差较大，即使同一类工艺同一性质固定源其颗粒物排放也存在不同，主要原因在于各企业的运行参数、固定源除尘设施、颗粒物检测方法及仪器等存在不同. 

PM2.5 Emission Characteristics of Different Stationary Sources in Cement Enterprise

In order to get the particle emission characteristics of different stationary sources in cement enterprises, the field test was carried out with self designed dilution collection system of PM_2.5 located at Guanzhong area in Shaanxi Province. The results showed that the kiln head mainly emitted smaller particles and the size distribution was related to the condensation, coagulation, coacervation and other mechanisms. The kiln tail, coal mill, crushing and cement mill mainly emitted larger particle sand their size distribution were related to the physical properties such as crushing and grinding of raw materials, fuels and clinker; In consideration of the standard dry flow rate of exhaust gas, the control points of stationary source PM_2.5 are kiln head, coal mill, kiln tail, cement mill and crushing in turn. The overall level of particles mass concentration of Aitken mode and accumulation mode in kiln head was obviously higher than that of kiln tail, coal mill and crushing. The difference between maximum values was about 3 times to 1 orders of magnitude. The common characteristics of mass concentration distribution in the kiln head, kiln tail, coal mill and crushing was that the most particles mass at different levels was larger than 0.1 μm in the particle size distribution spectrum of PM₁₀, and the mass change was more intense. The overall level of particles number concentration of Aitken mode and accumulation mode in kiln head is obviously higher than that of kiln tail, coal mill and crushing. The difference between maximum values was about 1-2 orders of magnitude. The common characteristics of the number concentration distribution in the kiln head, kiln tail, coal mill and crushing was that the number of coarse particles mode is very small in size distribution spectrum of PM₁₀. The emission factors of kiln end, kiln head, coal mill, crushing and cement mill was 0.156 clinker g/t, 3.914 clinker g/t, 1.538 coal g/t, 0.016 stone g/t and 0.056 cement g/t respectively, the total amount of PM_2.5 emission was 207.48, 5205.62, 286.38, 28.73 and 131.50 t respectively, and the total amount of PM_2.5 emission from stationary sources was 5859.7 t. The research showed that the particle emission characteristics from different stationary sources in cement enterprises was larger difference and the particle emission was also different even if the same property stationary sources and the same kind of production process because of the different operating parameters of the enterprises, the stationary sources dust removal facilities, the particle detection methods and the instruments.