生态环境第三方检测机构计量器具量值溯源管理问题探讨

构建科学、准确、有效的量值溯源体系是实验室质量管理的重要内容.在国家市场监督管理总局新发布的《实施强制管理的计量器具目录》中,涉及环境监测用途的类别大幅度减少.在此背景下,研究介绍了量值溯源中检定和校准的差异及适用范围,强调不应将检测作为量值溯源的方式.分类比较了国内现有具备量传能力的计量技术机构,对目前生态环境监测领...     

Packaging glass contained in the heavy residual fraction refused by Portuguese Mechanical and Biological Treatment plants

Mechanical and Biological Treatment (MBT) is an important strategy to manage Municipal Solid Waste (MSW) in Europe. The presence of recyclable materials on MSW depends on different factors such as inefficiencies in the Municipal Solid Waste collecting schemes and to the low level of citizenship environmental education. Among other products, MBT plants produce a residual fraction, named here as heavy residual fraction, that contains a significant amount of packaging glass which in Portugal is currently landfilled. This material is not recycled because it is heavily contaminated with other materials, preventing its processing in Material Recovery Facilities (MRF).In this paper the characterization, including particle size and composition, of the residual fraction of six Portuguese MBT plants is presented. The relevant variables that determine the heavy residual fraction characteristics were identified. It was observed that the MBTr particle size distribution is different and depends mainly on the place on the flowsheet where the MBTr exits the process, which is determined by the type of biological process and by the aperture of the last screen where the product passes through. The content in glass varies from 33 to 83%. These values are mainly related with the upstream glass sorting and with the efficiency of the recovery of the organic fraction which is the glass main contaminant. The second main contaminant is “stones”.The quantity of glass contained in this product in all the plants that will be in operation in Portugal in 2014 was estimated. The work shows that if all the 48,000 of glass could be recovered the Portuguese recycling rate would increase by 4.4%.