University of Cassino, via G. Di Biasio 43, 03043 Cassino, Italy.
Waste Manag. 2011 Nov;31(11):2253-62. doi: 10.1016/j.wasman.2011.06.017. Epub 2011 Jul 29.
Waste combustion processes are responsible of particles and gaseous emissions. Referring to the particle emission, in the last years specific attention was paid to ultrafine particles (UFPs, diameter less than 0.1 μm), mainly emitted by combustion processes. In fact, recent findings of toxicological and epidemiological studies indicate that fine and ultrafine particles could represent a risk for health and environment. Therefore, it is necessary to quantify particle emissions from incinerators also to perform an exposure assessment for the human populations living in their surrounding areas. To these purposes, in the present work an experimental campaign aimed to monitor UFPs was carried out at the incineration plant in San Vittore del Lazio (Italy). Particle size distributions and total concentrations were measured both at the stack and before the fabric filter inlet in order to evaluate the removal efficiency of the filter in terms of UFPs. A chemical characterization of UFPs in terms of heavy metal concentration was performed through a nuclear method, i.e., Instrumental Neutron Activation Analysis (INAA), as well as a mineralogical investigation was carried out through a Transmission Electron Microscope (TEM) equipped with an Energy Dispersive Spectrometer (EDS) in order to evaluate shape, crystalline state and mineral compound of sampled particles. Maximum values of 2.7 × 10(7) part. cm(-3) and 2.0 × 10(3) part. cm(-3) were found, respectively, for number concentration before and after the fabric filter showing a very high efficiency in particle removing by the fabric filter. With regard to heavy metal concentrations, the elements with higher boiling temperature present higher concentrations at lower diameters showing a not complete evaporation in the combustion section and the consequent condensation of semi-volatile compounds on solid nuclei. In terms of mineralogical and morphological analysis, the most abundant compounds found in samples collected before the fabric filter are Na-K-Pb oxides followed by phyllosilicates, otherwise, different oxides of comparable abundance were detected in the samples collected at the stack.
废物燃烧过程会产生颗粒和气态排放物。就颗粒排放物而言，近年来人们特别关注超细颗粒（UFPs，直径小于 0.1μm），这些颗粒主要由燃烧过程排放。事实上，最近的毒理学和流行病学研究结果表明，细颗粒和超细颗粒可能对健康和环境构成风险。因此，有必要量化焚烧厂的颗粒排放物，以便对居住在其周边地区的人群进行暴露评估。为此，在本工作中进行了一项旨在监测 UFP 的实验活动，该活动在意大利圣维托雷德拉扎罗（San Vittore del Lazio）的焚烧厂进行。在烟囱和纤维过滤器入口前分别测量了颗粒尺寸分布和总浓度，以评估过滤器对 UFPs 的去除效率。通过核方法即仪器中子活化分析（INAA）对 UFPs 的重金属浓度进行了化学特征分析，以及通过配备能量色散光谱仪（EDS）的透射电子显微镜（TEM）进行了矿物学研究，以评估采样颗粒的形状、晶体状态和矿物化合物。在纤维过滤器之前和之后，分别发现了数浓度的最大值 2.7×10(7) 个/cm(3) 和 2.0×10(3) 个/cm(3)，这表明纤维过滤器对颗粒的去除效率非常高。关于重金属浓度，沸点较高的元素在较低直径处具有较高的浓度，这表明在燃烧段没有完全蒸发，并且随后半挥发性化合物在固体核上冷凝。就矿物学和形态分析而言，在纤维过滤器之前收集的样品中发现的最丰富的化合物是 Na-K-Pb 氧化物，其次是层状硅酸盐，而在烟囱处收集的样品中检测到不同的类似丰度的氧化物。
